Antenna Arrays Could Replace Satellite TV Dishes

Zothecula writes "There was a time not so very long ago when people who wanted satellite TV or radio required dishes several feet across. Those have since been replaced by today's compact dishes, but now it looks like even those might be on the road to obsolescence. A recent PhD graduate from The Netherlands' University of Twente has designed a microchip that allows for a grid array of almost-flat antennae to receive satellite signals."

Comments

No

[sexconker]

This won't work.

Why?

Because satellite signals are extremely susceptible to atmospheric interference.

Raw size does matter here.
A larger receptor is better.

You may as well try to reproduce a high quality studio microphone with an array of dollar store clip on mics, and then toss out the typical dismissive bullshit claim of "The rest is just software!".

Re:No

[pixelpusher220]

Raw size does matter here. A larger receptor is better.

Which explains why the small dishes now do similar things that the old big ones did?

I suspect it *is* the software that can filter out/account for that interference on a slightly less quality signal that makes the smaller dishes do just fine.

Bigger is better at the extreme end of a broadcast range; i.e. listening for something from outside the solar system or something incredibly weak compared to background noise.

I would also bet that the satellites being used now are more powerful than the original communications sats. So higher signal means, smaller dishes are workable.

If a flat antenna can pickup the signal, I'm sure it will be a bit different than a parabolic concentrating dish. That's exactly was software is made to do. (aren't most internal cell phone antennas these days flat by design? thought I something a while back on fractals in antenna design towards that effect)

Re:No

[JonySuede]

does it snow a lot where you live ? If it does, can you please tell me the model of your small dish ?

Re:No

[Anonymous Coward]

It's the same principle as the highly directional virtual microphone computed from hundreds of ceiling mounted microphones. It's called a phased array. I guess what's new about it is that they expect to do this cheaply with signals in the 10GHz range.

Re:No

[Cytotoxic]

Raw size does matter here.
A larger receptor is better.

Which explains why the small dishes now do similar things that the old big ones did?

Or it could have something to do with the wavelength of the radio signal being received. Longer wavelengths require larger receivers. For an example compare your eyes (wavelengths measured in angstroms) with a radio telescope (wavelength measured in meters). (of course, power and efficiency also enter into it, but the bigger factor at play is the wavelength)

Re:No

[broomer]

No. The LNB has gotten better, the 'antenna' that a dish uses, they used to be 1.2 dB, and 0.9 dB if you wanted something expensive. todays standard is 0.3 dB, so you have enough with about a quarter of the original signal.

My not so expensive 6 year old dish system still receives the same signal strenght.

Re:No

[pixelpusher220]

Have the wavelengths of the sat broadcasts changed? This about using a new type of antenna to handle an existing broadcast, not trying to receive a different signal, no?

I suppose the old sats might use a different wavelength than say DirecTV sats I guess.

Re:No

[gstoddart]

does it snow a lot where you live ? If it does, can you please tell me the model of your small dish ?

Forget about snow. A friend used to lose his TV signal about 45 minutes before it rained.

Re:No

[Mister Transistor]

GP is correct - the dish size has all to do with the gain of the antenna, not the resonant frequency. The actual antenna is at the focal point of the dish and it's length IS frequency-critical. The surface area of the dish directly corresponds to its gain.

The reason we no longer use giant 6' dishes is twofold - because they are using 24 GHz instead of 5 GHz means the antenna at the focal point is much smaller, and the area of the dish is relatively the same size - with relationship to the wavelength - which is also much smaller.

The other reason is the peak power of, say the DirecTV sats, is as high as 150W for some transponders, whereas the older C-Band stuff was about 10W peak.

Dishes typically are designed to produce somewhere around 30dB of gain, which is 1000x magnification of the signal over a straight dipole with no reflector.

Re:No

[Phreakiture]

Which explains why the small dishes now do similar things that the old big ones did?

Your attribution of this effect is wrong.

The old 2m-3m satellite dishes were for receiving analogue signals. By going digital, it is far easier to detect and sufficiently correct for using a very weak signal. That gets the dish size down to about 1m. The other 50cm difference in size is due to the newer satellites using a higher power output.

Re:No

[Phreakiture]

Yes, and no.

The old satellites did use a longer wavelength, it is true. In both cases, however, the parabolic reflector in use is several orders of magnitude larger than any dimensions dictated by the wavelength. The only tuned element (which is where wavelength comes into play) is found at the narrow end of the feedhorn, up in the LNB.

The new ones are smaller because digital signalling has replaced analogue, in turn making error correction possible and sufficient for 99% of the time, and by the fact that the newer satellites put out a more powerful signal.

Re:No

[Lumpy]

It's the difference between C band and Ku band. C band is 5.850–6.425Ghz while the Ku Band is 12 to 18 GHz. you need a LOT LARGER dish for C band to get the same gain that a small dish at Ku band will get. THIS is the reason why today's home TV dishes are smaller. NOT technology or power. In fact a Lot of TV is still available on the C band. I have friends that have a couple of the big dishes and get a lot of channels, two pay for HBO and STARZ and get about 40 channels of them in the pack for about $100.00 a year.

The biggest advantages have been in low noise temperature Amplifiers and block converters.

With a small 36-38" dish and a premium LNB I can pull in DishTV through a tree during a massive rainstorm. My FTA setup regularly pulls in the europe birds through the neighbors trees with it's 120cm dish and it's invacom 0.3db quad LNB. The garbage grade 28" dish and trash grade LNB they give you when you get your "free install" can barely pull a good signal through a cloud.

Re:No

[Teun]

Have the wavelengths of the sat broadcasts changed?This about using a new type of antenna to handle an existing broadcast, not trying to receive a different signal, no? I suppose the old sats might use a different wavelength than say DirecTV sats I guess.

Yes, the old C-band has a much greater wavelength than the present Ku-band.

Re:No

[Anonymous Coward]

GP and YOU are mildly incorrect. WaveLength of the signal is impotant to the gain of the dish. a 5ghz signal has less gain on a 5 foot dish than a 20ghz signal does.

a 3 meter dish at 5 ghz has 21.704db of gain.
the same dish at 20 ghz has 54.415db of gain....

massively more gain on the same size of dish simply because of the frequency of the signal.

you also ignore that the LNA's used today are 20 times better than the ones from only 5 year ago.

Re:No

[Teun]

A well set up offset dish gives much less chance for snow to accumulate on it.

But during heavy showers you'll need more amplification than under a clear sky.

How you achieve the amplification, larger dish or better electronics, is fairly immaterial for the end result.

Re:No

[JonySuede]

ok thanks for the insight that: "How you achieve the amplification, larger dish or better electronics, is fairly immaterial for the end result."

Re:No

[ArhcAngel]

How long ago was that? Up until I got U-Verse I had been a Dish customer and I never lost signal even during hurricane Ike (I live in Houston). Well at least I didn't until the power went out. My next door neighbor lost her comcast cable about an hour after the storm hit and it was out for six weeks.

Re:No

[gstoddart]

How long ago was that?

After 2000, before 2004 for that particular person. I've seen the same on other dishes more recently, but I don't see it very often (satellite that is).

May be our latitude (I'm a fair bit North of you) and because our dishes are only tilted up about 15-20 degrees ... who knows. But, I've definitely seen it on numerous occasions, and still occasionally see it in bars when they have satellite TV.

Re:No

[Moof123]

"The actual antenna is at the focal point of the dish and it's length IS frequency-critical."

The dish is a simple parabola, it's focal point is not frequency dependent. Its gain IS frequency dependent however. Achieving the same gain at half the frequency requires double the dish size (or, double the frequency and you can halve the dish size for the same gain).

As long as the dish is smooth enough its focal point is not frequency dependent. At the extreme low end things fall apart (i.e. the dish becomes on the order of a wavelength in size).

Re:No

[dogsbreath]

Satellite dishes are smaller now because the original C band transponders were power limited compared to the current Ku band transponders. As well, antenna size is related to wavelength so equivalent antenna designs for a high frequency (Ku band) will be proportionately smaller than for a low frequency (C band).

So... sat-TV receiving dishes are smaller because both the satellite transmit power and frequency increased.

Digital Signal Processors (DSPs) can do a lot, but all receiver processing (analog or digital) depends on getting an analog signal from the antenna that has sufficient S/N and power. Think GIGO. It is the same with radio signals. With sat-TV DSPs are not the reason for the change to smaller antennas. It is almost entirely due to the change to higher power Ku-band transponders.

Various array antennas have been around for a long time. TFA doesn't give much detail and isn't even clear about what is being proposed but there is a better description here:

http://wwwhome.cs.utwente.nl/~burgwal/research.php

What is interesting about Burgwal's chip is that it could make a mass-produced array practical for a lot of purposes, including sat-TV receivers. That may not be the killer app for the chip tho since the dishes are cheap, efficient, and easy to set up.

Although, it would be nice to just stick a flat antenna device on a wall without any set up. A lot of installers would be out of work!

Re:No

[Matey-O]

The change in size was due to a move to Digital, NOT just an improvement in reception technology.

Re:No

[Anonymous Coward]

Raw size does matter here.
A larger receptor is better.

Which explains why the small dishes now do similar things that the old big ones did?

Dish size is 99.999% independent of signal wavelength. A dish provides a focal point. At that focal point, a horn antenna gathers that focused energy which is sent to the RF front end of the device.

All the dish antenna provides is a certain dB gain. The reason why equipment can get away with smaller antenna is because there are better low noise amplifiers to help recover the signal.

Satellites are also putting out the same amount of power as when they were first put into orbit. They were designed to continuously output a specific amount of power and that's exactly what they still provide.

Re:No

[Gerzel]

Being susceptible to interference does not mean that a minimum size is required or has been reached for the detector.

You could just as easily and with as much validity use the same argument on the old style large satellite dishes. However for most consumers' needs the new smaller ones work just as well, are easier to deploy and cheaper.

These new arrays when they come to market will probably be just as good for the average consumer, smaller and thus easier to deploy.

I'm already getting sat radio through a device that could almost be hand-held for my car. Video signal is just more throughput.

Re:No

[dogsbreath]

I don't believe that DSP implementation in receivers was responsible for smaller antennas. If you have some references you can point me at I would appreciate it.

In a 40 Mbs tv digital stream there is about 17 Mbs of forward error correction. This allows the base fairweather signal to still be usable when rain/snow deteriorates the reception. This means that instead of losing your reception when it rains, you can still watch Jersey Shore (or Big Bang).

DSP implemented communication sets usually don't have any better sensitivity specs than analog units but they do have a lot more flexibility and functionality. For example: an NRD 545 receiver is almost all DSP and is very sensitive (.32uv for 10db) but an analog Drake receiver is better at 0.25uv. I kno this is an analog audio modulation and not digital video but very basically it is about pulling a usable signal out of the noise.

However, the NRD has an incredible set of features for dealing with the signal, including notch filters and continuously variable bandwidth.

Basically, though, what comes out of the analog front-end is what is important and what determines whether or not a signal is useful. The error correction allows signal deterioration due to weather or other conditions to not affect reception until things get really bad.

Re:No

[nobodylocalhost]

Raw size does matter here.

That's what she said.

Re:No

[N3Bruce]

Antenna performance (in this case a parabolic dish) depends on several factors. The old C-Band dishes needed to be 10 feet across due to relatively low power on the downlink, and because the gain of a dish depends on its size relative to the wavelength of the signal. C-Band used a 4.7 Ghz signal, which has a wavelength of about 6.3 cm, or about an 2.5 inches. Later dishes received Ku band signals, where were about 11 Ghz, which have a wavelength of 2.7cm, or a little bit more than an inch. Proportionately, a 4 foot Ku band dish has about the same theoretical gain as a 10 C-Band dish. The newer satellites are also more powerful, and preamp performance is improved as well, which is why a 2 foot "hubcap" dish can pretty much do the same thing as the old 10 foot C-band dishes.

Too much gain can have drawbacks as well. If you can aim one of the old 10 foot dishes adequately, you will get EXCELLENT performance on Ku band, but with increased gain comes a narrower beamwidth, which makes the dish harder to aim at the desired satellite. The smaller dishes are a much more rugged, stable, and less expensive platform than the 10 footers of old, which needed massive foundations and supports to maintain stability, particularly in high winds.

Re:No

[Viperpete]

You probably caught the Nova Episode about fractals, it has a segment where it talks about fractal phone antennas:

http://www.hulu.com/watch/181084/nova-hunting-the-hidden-dimension

Here's some other stuff:

http://en.wikipedia.org/wiki/Fractal_antenna

http://classes.yale.edu/fractals/Panorama/ManuFractals/FractalAntennas/FractalAntennas.html

http://www.fractenna.com/

Re:No

[mirix]

dB is log, so that's not really right.

for example (I don't know which units sat uses, but it isn't really relevant except in absolute terms)
0,3dBm = 1.07mW
1,2dBm = 1.32mW

It's a slight improvement, not 4 fold.

Re:No

[smpoole7]

>The change in size was due to a move to Digital, NOT just an improvement in reception technology.

Ummm ... yes and no. If you listen to talk radio, virtually all of those voices (whether conservative or liberal) have two things in common: (1) they're distributed digitally (typically with some variant of MPEG or AAC, for the curious. and with VERY robust error correction) and virtually all of them are delivered via C-band satellite. Rush, Phil Hendrie, Laura Ingraham, you name it. We have both a 3 meter and a 3.2 meter dish at our radio stations. The satellite providers recommend these dish sizes, even with digital signals.

As others here have pointed out, the higher the frequency, the smaller the dish can be for the same gain. You could use a humongous dish for Ku Band, but it would be a waste, especially with a digital signal. (That's where you're partially correct, which is why I said, "yes and no.")

However, also in fairness to you, there's beamwidth (i.e., the ability to reject other satellites to either side of the one you want). That's one big reason why we still have to use the giant, honkin', hateful, heavy and HUGE 3 meter dishes. The C band is a nightmare and has been for years.

By the way, on the original subject ... phased/grid arrays have been around for decades. The fact that someone has developed a better chip is interesting news, but it's hardly earth-shattering.

The real reason why dishes continue to outsell most other types of antennas is cost-vs-benefit ratio. They're cheap, they provide a "good enough" signal, and they get the job done.

Re:No

[Anonymous Coward]

The modern small dishes "work better" than the big, older dishes because the satellites are much more powerful now. That's all.

Satellite TV was not originally meant for mass home use. The satellites were relatively low powered and weak. It took a big dish to get a decent signal, and a very big dish for broadcast quality signal.

Lessons learned from that went into DBS. DBS was designed from the start to use different radio bands and much bigger and more powerful satellites which allowed for smaller receiver dishes, and the dishes were designed for a fixed mount to eliminate the need for an aiming controller. This simplified the receiver boxes, along with some other things designed to make it cheaper to manufacture.

The satellites have gotten progressively more and more powerful as well, with more and more transponders, and many of them are located closer together than before, which also increases channel density. Most of this is transparent to the end consumer, naturally.

But the bottom line is that the high power birds are what makes it work as well as it does. Without that, the dish itself is junk.

Re:No

[tuxicle]

The older analog receivers required more bandwidth per channel. Modern satellite TV is digital, the compression means each channel needs less bandwidth, and will work with lower SNR than the analog channels.

Re:No

[Anonymous Coward]

It's not just the LNAs. It's also that we are no longer using separate LNA and LNCs. Less parts means less signal losses.

I can remember having to choose a feedhorn, then the LNA, then the optimal LNC and worrying about terrifying coax losses trying to get the signal received and down converted and in the house. Sure it worked but it could be interesting when it didn't.

Now, all of that is handled right in the LNB and the whole part is $40 new, or less at flea markets. This is the unsung innovation of DBS. Stuff that used to be close to home brew or at least contain a good deal of magic is now off the shelf and stuck on the sides of millions of homes.

Re:No

[Artifakt]

I replaced the 18" oval dish that normally comes with DirecTV installs now with an older 1 meter K band dish. I used the LNBF and cables from my current install - just replaced the cheap metal dish and mounting arm itself. Why did I bother? I used to lose signal whenever the rain got to over about one inch per hour. The service terms actually warned of possible losses for any rate above 1/2 an inch per hour, so we can safely assume the old dish was an above average install. I had a spare 1 meter dish that I acquired doing a free to air steerable install, and so it cost me nothing except time sighting the system in. The new version has never lost signal during severe weather. Now ask yourself one more question and the point should be clear - Is it more likely to be raining less than 1/2 inch per hour when they broadcast a killer F-5 tornado warning, or more than that?

See, it's your statement about "small dishes now do similar things that the old big ones did" - the design specs for the original 1 meter disk specify two inches of rain an hour, and the new ones specify 1/2 an inch. The people who sell them don't claim the new design does everything the old one does, they promise only 1/4 of the performance in that one particular respect. 1/2 an inch of rain an hour is now that extreme end of the broadcast range you thought was only about talking to the Mars Observer. (And that's measured well south of, say, New York City or Toronto or Boston, where the line of sight is passing through much more thick air. See, we are operating on the fringes of the feasible much more than most people recognise).

Incidentally, you can get cheap K frequency transparent plastic domes to fit the concave face of a full meter dish, so it offers less wind response than an unshielded smaller dish, further improving your reliability. I found out about those because the NOAA lab and the local police and fire stations all put them up at the same time and there was a piece in the local paper about it. I don't think anyone bothers to make those for the little dishes.

This is still a neat technology though. If I lived in an apartment where a full meter object on the roof was awkward, I'd be looking into it more.

Re:No

[spambucket235]

That's why God invented FEC. Isn't it?

Re:No

[Neil Boekend]

No. An analog receiver could work with way worse signals. The image wouldn't be good but there would be an image, while the digital receiver would state something like: "no signal". Many a farmer in my area was appalled by that. As many educated people have stated: the frequency is the change that caused the dishes to be smaller.

Re:No

[Anonymous Coward]

I think you are misinterpreting the previous post - I don't think he was referring to DSP processing (which could be used to clean up analogue signals) but to digial error correction as in, say, Reed-Solomon or Viterbi, where redundant bits are transmitted and then allow a certain % of errors to be eliminated.

Re:No

[Teun]

Yeah, I should be a well paid politician :)

Why?

[commodore64_love]

Surely the small parabolic dish is more compact/efficient than an antenna array? I looked at the article but it doesn't show any pictures of what these new antennas would look like.

It would be cool if something like this could be used to replace the big, bulky antennas needed for Broadcast TV and Radio.

Re:Why?

[drachenstern]

Ok, but I live in an apartment in an old (historic, something like 117 years old so far) building and they won't let us attach anything to the exterior walls/roof. My windows all face north. I want to use a satellite to receive more programming. I am adverse to paying Comcast one more dime.

What are my options again?

This sounds great, if it would work for me. The 16 foot ceilings mean I could talk the wife into letting me mount even a mesh in the ceiling area of the apartment, if I could conceal it afterwards.

Re:Why?

[Anonymous Coward]

The array will be flat and won't have to be aimed. That means the antenna could be mounted flush on the wall or the roof. That means it could also be much larger because it would be less of an eyesore and there would be no wind load. No aiming also means the same antenna could be used to receive signals from several satellites, without a motor mount or delays.

Re:Why?

[LWATCDR]

It sounds a lot like a phased array to me. Not really new.
And why? Well some people might not like the look. They will fair better in high winds and with snow loads. Also they will work much better for vehicles. Combine it with a GPS and it can track a satellite while you move.
It could also switch between satellites on it's own.
In theory you could even use it with none geosyc satellites. As one comes into view you could switch beween them in a very rapid mannor. That could allow for a much lower latency internet connection and or higher bandwidth as well as working in places where a geosync connection is difficult like near the poles.

Re:Why?

[Nyeerrmm]

Its probably a phased array antenna http://en.wikipedia.org/wiki/Phased_array. The big thing here isn't the fact that its been done, but that the chip makes it easy, cheap, and fast to manufacture one. The actual size wouldn't be very different, since the size is based on the required gain, and the physics don't change for a parabolic antenna or a phased array.

The big advantage I see to this is two-fold: 1. Mounts flat so it is much less of an eyesore. Also you could conceivably hide it behind something that is radio transparent. 2. Can be pointed via software, so that the physical installation only needs to be pointed in the rough direction of the satellite.

Re:Why?

[PRMan]

The rules may be illegal.

FCC Rules on Antenna/Dish placement

Re:Why?

[h4rr4r]

Hook up a dish, they cannot stop you, you might have to put it on a pole in the yard. The FCC is a higher authority than your landlord.

Re:Why?

[Aquina]

I aslo think that is the most interesting aspect of the whole story. Movies showing space crafts with all their dishes at 'em will have to be rewriten. ;-)

Re:Why?

[Anonymous Coward]

The big advantage I see to this is two-fold:

1. Mounts flat so it is much less of an eyesore. Also you could conceivably hide it behind something that is radio transparent.

2. Can be pointed via software, so that the physical installation only needs to be pointed in the rough direction of the satellite.

Well, #2 is *huge*. You just point the thing south and BOOM, you have access to 40 satellites with one receiver! Even if it has to be 2x or 3x the surface area to compensate, phased array like this is very useful.

It's been done in Astronomy - now that same tech is making TV more accessible. Science at work.

Re:Why?

[Obfuscant]

From the link you provided:

"The rule allows local governments, community associations and landlords to enforce restrictions that do not impair the installation, maintenance or use of the types of antennas described above, as well as restrictions needed for safety or historic preservation. Under some circumstances where a central or common antenna is available, a community association or landlord may restrict the installation of individual antennas. The rule does not apply to common areas that are owned by a landlord, a community association, or jointly by condominium or cooperative owners where the antenna user does not have an exclusive use area. Such common areas may include the roof or exterior wall of a multiple dwelling unit. Therefore, restrictions on antennas installed in or on such common areas are enforceable."

Looks like the restriction is probably legal. He doesn't have exclusive use of the south-facing wall (or any use, apparently), and a 117-year-old house is certainly on the Historic Register.

Re:Why?

[Anonymous Coward]

Wavelength are short due to frequencies around 10 GHz, I think. Antenna elements / dipols correspond to the wavelength and get also small. Now you take a lot of those little dipols, sum their signals up in a phase corrected way and you get a good signal to noise ratio. The idea is rather old and simple. Wonder, why no big company before put it into practise, but kudoz to the guy, who did it.

Re:Why?

[Anonymous Coward]

Didn't bother to read your own link? A quick search for "historic" brought up this:

"The rule does not prohibit legitimate safety restrictions or restrictions designed to preserve designated or eligible historic or prehistoric properties, provided the restriction is no more burdensome than necessary to accomplish the safety or preservation purpose."

Given that, I think the rule that "they won't let us attach anything to the exterior walls/roof" is likely in compliance. Granted, that does stop him from (as h4rr4r suggested) putting it on a pole in the yard (probably pretty hard to argue that the grass is historic and would be irreparably damaged). The only trick would be coming to an agreement on how to get the wiring into the house (though since they already let comcast bring in wire, there's got to be a way to deal with this)

Re:Why?

[Anonymous Coward]

Q: What types of restrictions are prohibited?

A: The rule prohibits restrictions that impair a person's ability to install, maintain, or use an antenna covered by the rule. The rule applies to state or local laws or regulations, including zoning, land-use or building regulations, private covenants, homeowners' association rules, condominium or cooperative association restrictions, lease restrictions, or similar restrictions on property within the exclusive use or control of the antenna user where the user has an ownership or leasehold interest in the property. A restriction impairs if it: (1) unreasonably delays or prevents use of; (2) unreasonably increases the cost of; or (3) precludes a person from receiving or transmitting an acceptable quality signal from an antenna covered under the rule. The rule does not prohibit legitimate safety restrictions or restrictions designed to preserve designated or eligible historic or prehistoric properties, provided the restriction is no more burdensome than necessary to accomplish the safety or preservation purpose.

tl;dr

historic building restriction is a-ok

Re:Why?

[Lumpy]

your options are to contact the FCC and state to see the laws you have in your area concerning the right to receive TV.

Your Local Historic district gestapo cant do crap to keep you from putting up a satellite TV dish.

http://www.fcc.gov/mb/facts/otard.html

verify your rights and then have one installed and tell the historic commission to stuff it in their rectum.

Re:Why?

[Mister Transistor]

Take a look at a modern battle Tank or Destroyer class missile cruiser - they have flat angled sides with these roundish "targets" in the middle. A close-up reveals those circles to be composed of hundreds of individual antennas in a circle-shaped array. Our AEGIS missile cruisers were the first to get this, now land vehicles like tanks and the new ADS (Active Denial System - the "death ray" weapon) use phased array antennas like the ones on shipboard, just smaller...

Re:Why?

[Anonymous Coward]

the OTARD rules will never allow you to attach a dish permanently to an apartment. You can legally pole mount it to a pole sunk in the ground in your "exclusive use area" patio. pole mount it using a pole in a 5gal bucket full of concrete, tripod mount it, possibly mount it to balcony railing using a system that clamps around the railing. There area also systems that will hang off south facing window ledges and nothing stopping you from setting it up inside next to a south facing window, so long as you dont mind the loss of space and dont have kids or pets that are going to bump the dish.

Re:Why?

[natehoy]

Granted, that does stop him from (as h4rr4r suggested) putting it on a pole in the yard (probably pretty hard to argue that the grass is historic and would be irreparably damaged).

Sorry, that falls under the common area owned by the landlord. IANAL, but I've helped a few friends iron out details on this with their landlords and/or homeowner's associations. This particular case, however, appears to be a lost one. GGP could probably hang a dish outside his window, assuming his window was facing in the correct direction (which, in his case, it is not) and he could do so safely while not making it a permanent installation. But he's in the "rare exception" list that has no legally-protected solution for installing a dish. He can only make a temporary installation in the areas he has rented, and he doesn't control any areas that would allow him to receive signal.

However, a phased array could still be a winning solution there, because current units tend to be pretty small and subtle compared to a dish, and may not be as objectionable as a dish. Most of them are relatively small sealed discs that can be mounted on any flat surface at a variety of angles as long as they are pointed somewhat vaguely in the direction of the South sky (as seen from North America), and can be painted to match the surrounds in many cases. So the landlord (and historical district) might not object to a small disc mounted on the South side of the building roof with a wire running around to his window, for example, where actually screwing a DirectTV dish might be somewhat more controversial.

Of course, phased array units don't come cheap.

A couple of "first I found on Google" examples of phased-array satellite units currently available (I'm not recommending for or against these specific units at all, just a couple of examples of currently-available tech):

http://www.solidsignal.com/pview.asp?mc=06&p=KVHA7&d=KVH-TracVision-A7-InMotion-SUVMiniVan-DIRECTV-Satellite-TV-Antenna-System-(A7)&c=Satellite%20Dishes%20for%20SUVs&sku=

http://www.solidsignal.com/pview.asp?mc=06&p=01-0263-04&d=KVH-TracVision-R6-ST-InMotion-Statellite-TV-Antenna-System-w-Integrated-12V-DirecTV-Receiver-(R6ST)&c=Satellite%20Dishes%20for%20SUVs&sku=

So instead of one larger disc-shaped unit like the ones pictured above you could deploy a handful of really tiny units over a larger area and have them phase together to pick up a better signal. Put them far enough apart, and you could easily reproduce the effect of a 15-foot or even larger directional dish and resolve signal through some fairly significant material or interference.

In that case, the person who started this discussion might be able to get a signal, even through a roof, with enough phased elements spread over a large enough area. He'd have all of the bits inside his area of control and installed temporarily (and not have a 15-foot dish sitting in the middle of his living room that might upset his wife).

Alternatively, he might be able to get approval for a half-dozen flat bits of painted metal to be temporarily glued to the corners of the roof, with thin subtle wires run to his window, since none of the installations are considered permanent and would not affect the historic nature of the house in any way.

Re:Why?

[Red Flayer]

Looks like the restriction is probably legal. He doesn't have exclusive use of the south-facing wall (or any use, apparently), and a 117-year-old house is certainly on the Historic Register.

Depends on where you live. Where I live, buildings that new are most certainly NOT on the historic register unless they happen to have other historical significance besides age. Keep in mind also that owners can choose to *not* put their buildings on the historic register -- the designation has drawbacks as well as advantages.

In college, I lived for a year in a house that had been built in the 1840s. It was a piece of shit, and the owner was a slumlord. The walls were literally falling down (plaster over rotten lathe) -- he told us if we wanted it fixed, he'd buy the materials but we'd have to fix it ourselves. He dropped off two rolls of duct tape and a gallon of cheap-ass paint. Seriously. I mean, I love duct tape as much as the next guy, but to fix a wall?

Anyway... where was I... oh yes. I think you nailed it with the "exclusive use" bit, but the historic bit may or may not apply.

Re:Why?

[natehoy]

They can't stop him from putting up a temporary installation on any part of the building he is renting. In this case, he's rented a north-facing apartment, which means his windows are useless for a dish install, and unless he's specifically renting a bit of yard, the landlord can in fact stop him from installing a dish in a common area.

I've helped friends fight a few homeowner's associations and/or landlords hostile to a "temporary balcony or window dish" or a rooftop TV antenna. I'm not a lawyer, but I'm relatively familiar with this specific law. And, sadly, this one's pretty much a lost cause if the landlord won't allow him access to common areas.

His best bet is to look up the current crop of phased array satellite antennas and see if the landlord could tolerate one of those installed temporarily somewhere subtle on the building. They're a lot less ugly than dishes and can be installed far more creatively, and they don't need to be aimed. But they are expensive.

Re:Why?

[natehoy]

#2 is even bigger than huge, because it removes the need for geosync satellites, meaning someone could orbit some satellites at a much lower orbit and the phased array could track them in real time. That means much cheaper costs put your birds into low-earth orbit, much lower power the satellite has to put out and much higher frequencies available for signal density, and much lower latency. Screw TV, we're talking viable satellite telephone and low-latency satellite Internet access. Hell, you could launch a bunch of high-altitude drones powered by solar arrays and a phased array antenna would have no problems picking up the nearest dozen of them simultaneously.

Phased arrays are currently available, you can buy one today. They've been available to the consumer market for years. They do, however, draw some significant power and start in the thousand-dollar range. I suspect this is more about making them cheaper and less power-hungry. The beauty of cheap, low-power phased array is that you can orbit the cheaper satellites and still have affordable no-moving-parts antennas that can use them. Cell companies don't need to install hundreds of towers to blanket a state with signal, they can orbit some drones or put up a half-dozen LEO satellites and get the whole country at once.

Re:Why?

[natehoy]

Lots of companies have put this into practice. Phased array satellite dishes are a commodity item (admittedly an EXPENSIVE commodity, but not at all rare).

I think this is about getting prices and power requirements down to a point somewhat competitive with fixed-dish installs.

Re:Why?

[Plekto]

The common thing to do here is to mount the dish to one of the vents up on the roof(which are almost NEVER in view of the street). That way, it's a 5 minute job to remove it if it needs to be. Just loosen the mount and slide it off. Zero damage. Of course, you're out of luck unless you're on the top floor. Yet one of many reasons I never rent on the lower floors.

Re:Why?

[drachenstern]

Or deal with it? I don't have a balcony.

The rule does not apply to common areas that are owned by a landlord, a community association, or jointly by condominium or cooperative owners where the antenna user does not have an exclusive use area. Such common areas may include the roof or exterior wall of a multiple dwelling unit. Therefore, restrictions on antennas installed in or on such common areas are enforceable.

Re:Why?

[drachenstern]

Ya know, I really wasn't going to worry over it. I was getting my mind all made up to just move over to a completely wired-delivery life, and go ad-hoc like the up and coming trend seems to be (or: like the trend seems to be if you listen to twit.tv) and have been trying to get my wife to understand just what Hulu and the like are, and to use DSL for that delivery, but then I read that there may be a way to do it from inside the apartment.

Ah well...

As for putting things on the roof, nope. But installing a phased array in the upper part of my living room is an option. Right up until I looked at those links you sent me and found that it would cost well more than it would be worth to me to try and put something in ... for $2100 I'll buy the shows I want to watch on iTunes ;)

Re:Why?

[drachenstern]

I don't normally feed the trolls, but in this case:

Meh, I'm glad that I'm able to walk to 40% of the places I want to visit instead of needing to use my auto. I chose to live in an area that was downtown and if the price I have to pay is the lack of satellite TV, well, I guess that's the price I'll pay to try and live a little bit greener. Not that I need a satellite anyways. I'm a bit more interested in getting out and seeing my community than staying at home watching TV.

I have a feeling, however that you may enjoy coming over to my "historic apartment roof" and correcting your own miserable life with a little fast-action freefall-dive instant-stopping.

Ok, that's enough feeding the trolls for one day.

Re:Why?

[nmg196]

Because you can't easily use a parabolic dish which needs to be aimed accurately on a car, caravan/RV/mobile home etc. This technology could potentially make it easier to resolve the weak satellite signals which would normally require a dish, resolvable by a static antenna array which could be omnidirectional. As the article implies, it might mean that digital radio actually *works* :)

Re:Why?

[nmg196]

> Ok, but I live in an apartment in an old (historic, something like 117 years old so far)

Historic?! You must be American! My building was built in 1810 and has 18" thick solid walls (try getting WiFi to go through that - or a drill bit long enough to run the Cat 5 though).

But yes, we have the same problem - no dishes or even aerials are allowed on our building, so hopefully this technology will allow those of us in listed/protected buildings to get satellite-based services.

Re:Why?

[xaxa]

Keep in mind also that owners can choose to *not* put their buildings on the historic register -- the designation has drawbacks as well as advantages.

What is the historic register? (I'm not American.) Over here the government decides. There are various restrictions on what you can do to these buildings, depending how historically interesting they are. An owner can contest the decision, but that's it -- and ignoring the restrictions is a criminal offence.

In college, I lived for a year in a house that had been built in the 1840s. It was a piece of shit, and the owner was a slumlord. The walls were literally falling down

The owner here would be required to maintain a historic building. The whole point is that it doesn't fall down...

Re:Why?

[Anonymous Coward]

There are three main advantages that spring to mind:

- parabolic dishes need to be pointed directly at the source, which can make mounting tricky if you don't have any appropriately oriented roofspace. With an antenna array you can point it in roughly the right direction (aka "up") and use electronic beamforming to "tune in" to the direction you want.
- parabolic dishes must be parabolic by definition - so you need to mount a big ugly wind-catcher (and blown-awayer-in-stormy-weather) somewhere. A flat (or in principle curved to whatever shape you like, though I don't know if this particular verison would allow for that) antenna array is much more convenient.
- if you need a *really big* parabolic dish for some reason then that would be a major pain. If you've ever watched the dish you'll know what I mean. An equivalent array is just some antennas spread over a wide area and is much easier and cheaper to deal with this. Radio astronomers have been taking advantage of this for decades.

Re:Why?

[natehoy]

Right up until I looked at those links you sent me and found that it would cost well more than it would be worth to me to try and put something in ... for $2100 I'll buy the shows I want to watch on iTunes ;)

Exactly. And that is the (theorized) breakthrough that this idea provides. Not phased array, hell we've had that for the better part of a century now. But AFFORDABLE phased array.

Re:Why?

[natehoy]

Very true, and the "Hysterical Society" can't legally have a gripe with it since it is not a permanent change to the structure.

Unfortunately, that also requires the approval of his landlord, same as the "dish in the yard" possibility, since the yard and roof are both common property.

On the other hand, a disc-shaped plastic piece painted to match the roof color might not be objectionable to a landlord, where a 3-foot-wide dish on a post in the yard would almost certainly be. Less chance of vandalism up on the roof, too.

Re:Why?

[Anonymous Coward]

Here's some ideas:

Get/find/borrow a dish and set it up with a receiver sufficient enough to test for signal. Stuff from a yardsale will do, so long as it works. Don't subscribe. ANY box will let you test for signal. So get the stuff working and set it up in whatever room you have facing your home's southern-most side. Yes, indoors. Yes, I said set it up indoors.

You will have to have some luck and tweak it very carefully, but you just might be able to get some signal through the wall. It's worth $10 bucks for stuff from a yard sale and a piece of coax.

If that does not work, find a neighbor with a south view and make them some cookies. Then ask them to let you try the same thing, maybe even with a view out a southern window. If it works, then the hard part is convincing them to let you bolt the dish in place. I've had good luck mounting them to furniture, inside hollow boxes, etc. Remember the mounting pipe is NOT required. You can work with a dish that is only the dish and the LNB arm and homemade stuff mounting it to something. The bottom line: if microwaves can get in, it just might work.

If it works, run cable to your place and give your neighbor free sat TV with a mirrored receiver on your account. And hope they don't change their mind or move.

Another option is mounting inside an attic. Yes indoors again. Come on people! Aiming is again tricky but can be done. What the roof is made from matters. An old house likely has tar paper over wood. Might work. Obviously it will not work with a metal or stone roof. If the landlord is likely to discover it, you will probably be caught eventually. But in some cases where you can sneak into the attic, you might be able to do it. You can also box it in with wood that can make it look like it's just a wood part of the roof structure.

Another tip: to get sat TV without a contract, hit yard sales, flea markets, pawn shops, Craigslist, and hamfests for older receivers that were actually sold to people (today's receivers are all leased). They go for cheap as noted earlier. GET the remote with it. No remote means you are not going to have fun. Often somebody will throw in a dish for free or cheap. Get the right kind of dish for the service you are choosing. But remember: you don't want leased receivers -check the labels for warnings about that. You want ones you can legally own. Once you have the gear, get some RG6QS, do a self install as noted above. Once it's all working and the test channel is working, call the company and tell them you have a working system, please send you new access cards. With DirecTV, sometimes they are $20, sometimes free. Wait for the Fedex to come and you are done! You have a no-contract system too, unlike everybody else. The downside is that usually HD receivers are all lease-only so this won't work. But if you can do SD sat TV, then you are good to go.

Hope this helps

Re:Why?

[Rich0]

You can also stick one of these on the roof of your truck or whatever and now you can have continuous high-bandwidth satellite communication while driving, since you could track a satellite in realtime as you hit bumps/etc. That's probably a harder trick, but as long as you're fast enough it should be possible.

I'd also think that phased array would be easier to mount - just lay it flat on your roof or whatever.

I'd be curious about other applications for this. If you got cheap phased array you could make radar applications a lot more practical. If you can cheaply deploy phased arrays all over the place that also could have signals intelligence applications, or stealth detection applications, or it might work well for things like cell towers, etc.

Re:Why?

[Hadlock]

What's a historic register? It means it's registered as a historic (i.e. old, typically the original building on that site from when the town was small) building with the city/state, and/or has historical significance. It means you need a court order to tear it down or (in Dallas at least) even change the design of the front door.
 
I lived in a historic register house for a while; from a cynic's point of view it's used by other land owners in the area to enforce certain building codes to keep their property values high. It varies from area to area but the neighborhood I was in listed all the houses as historic, and the neighborhood association had been granted the power to oversee additions/modifications of housing there. Three houses down from me a guy got permission, and built a 1.5 story, 3 car garage in his back yard (replacing the carport that was there) and completely re-landscaped the backyard.... with neighborhood association's approval of course. On the flip side, we had a broken a** front door because the landlord didn't want to jump through the legal hoops to get it replaced.

Re:Why?

[monkyyy]

", but as long as you're fast enough it should be possible."
"or it might work well for things like cell towers"
new fad among teen drivers speeding to get the internet for their internet on their new fangled evil tech on bumpy roads
coming up next we ask an expert y speed and y bumpy roads

Re:Why?

[Anonymous Coward]

In that regard, it'd be perfect for vehicular use. That description makes the application obvious. RV drivers wouldn't have to dick around setting up a dish and putting it away every time they make camp. Installation would involve putting the flat panel on the roof, running the wires, and being done with it. If the aiming is done entirely electronically, it also means that with a GPS you could maintain signal lock while the vehicle is moving. Not that the driver should be watching it, but passengers would have more choices than DVDs or regular TV broadcast during their ride.

Re:Why?

[Anonymous Coward]

Not exactly new. BSB trotted something similar out in the '80s in the UK. See http://en.wikipedia.org/wiki/Squarial

Re:Why?

[Rich0]

Think about trucking companies that use satellite tracking and routing. Think about traffic/weather data reporting. There are lots of benefits from networking vehicles beyond browsing facebook at 55mph. The companies that deploy these kinds of solutions are VERY aware of the dangers of driver distraction and info overload.

non-problem solved!

[RapmasterT]

so now I can have an array of small (?) flat antenna instead of one medium sized one? Is that better? I'm sure there's some cool scientific breakthrough here, but the article left me wondering what it is.

Re:non-problem solved!

[auntieNeo]

The article says that the antennas would not need to be physically aimed like dishes.

Re:non-problem solved!

[Anonymous Coward]

Directv already had this using a tracvision antenna you see mounted to the top of cars.

There's no reason you couldn't put one of these on the roof of your house, but why your house doesn't move so why use overkill tech? and whats so troublesome about a small dish on your house? any competent installer can find a way to install a dish that is not visible from the street if it's that big a deal for you

http://www.gizmora.com/tracvision-a7-satellite-system-for-vehicles-by-directv/

Re:non-problem solved!

[Cramer]

It does have to be aimed in roughly the right direction. However, it does not require precise tuning. I've used a BGAN system that used a tiny, flat receiver... you just have to get it close for it to work.

Re:non-problem solved!

[AK Marc]

Simultaneous access to all satellites in the sky, impossible with a traditional dish. Repointing the dish in realtime remotely, impossible with a traditional fixed dish. Installation flexibility impossible with a traditional dish.

Those may not be valuable for you, but they are valuable for someone out there. The article was about the science, not the marketing. Come back in 12 months for the marketing take on it. I'm sure they'll have thought up more than I did in the last 30 seconds.

Re:non-problem solved!

[Anonymous Coward]

Thinking that every flat antenna is a phased array = fail.

Unlike a panel antenna with gain built-in (and that gain correspondingly weak as you loosen the beamwidth to relax aiming), the array can be made of anything down to dipoles (possibly with different axes) for rather little directionality, then by combining the signals with appropriate phase shift, you get gain from the combined aperture, but can now control the directionality over a broad range, up to a full sphere (depending on the array design).

Re:non-problem solved!

[Rich0]

Yup, imagine a cell tower that broadcasts direction signals at each of 50 different phones that have open channels. That tower would have much larger range, and the phones could use much lower power. This would probably work well for any time-division protocol - during each time slot you point the antenna at only the phones that can talk during that time slot, greatly increasing your gain.

Phased array gives you a lot of options...

Relevant info?

[Monkeedude1212]

So, I'm no expert on signal analysis, but I understand the whole concept of Satellite Dish arrays and why we have those big fields of Giant Dishes pointed at the stars to read incoming data.

This article doesn't seem to point out any of the information that might be handy. How far apart do your antenna's need to be, how big exactly do they need to be, how many, all that good stuff.

For all I know, it might need a hundred of centimeter long antenna's spread across the entire length of my yard. Would THAT make a dish obsolete?

Re:Relevant info?

[PolygamousRanchKid]

For all I know, it might need a hundred of centimeter long antenna's spread across the entire length of my yard. Would THAT make a dish obsolete?

Well, think of that antenna array as being punji sticks: http://en.wikipedia.org/wiki/Punji_stick

No need to scream "Get off my lawn!" anymore.

Just let the buzzards pick up the carcasses . . .

Re:Relevant info?

[Archangel Michael]

Because it isn't all you know, the answer is "yes" it will make dishes obsolete. Assuming the worst and speculating on that doesn't help things. Wait till you see the antenna array the size of a sheet of A10 paper mounted to the roof of your house.

When people talk about making something else obsolete, they are usually know what they* are talking about.

*Exceptions include Marketing Droids and brain dead CEOs

Re:Relevant info?

[Caerdwyn]

Antenna elements in an array are usually about 1/2 wavelength apart. L-band, 1ghz to 2ghz, has a wavelength of 20 to 30cm. So... half that, assuming 1/2 wave separation.

Re:Relevant info?

[Anonymous Coward]

It's the Netherlands. European satellite TV is synonymous with ku-band, 10.7-12.7 GHz.

Re:Relevant info?

[sjames]

The problem is, we often hear that from the marketing droids and CEOs. Sometimes they get a tech to be their puppet for that statement.

The other issue is that sometimes knowledgeable and very rational people make that claim without understanding the unadulterated irrationality of the modern market.

Re:Relevant info?

[Caerdwyn]

It's the Netherlands. European satellite TV is synonymous with ku-band, 10.7-12.7 GHz.

The tech being described would be frequency-agnostic; the big question is how many elements it can manage. With higher frequencies and shorter wavelengths, the ability to phase-shift becomes coarser and coarser (the time-delay adjustment needed is measured in picosecond increments at 10GHz), and doing so digitally is not the easiest task. If the phasing adjustments are done digitally, the "dedicated hardware" approach that the professor seems to be using would be the solution to the expense that would be involved using off-the-shelf discrete picosecond/femtosecond oscillators. It would also allow for a large number of antenna elements to be managed; it would scale well and allow for a very high-gain array made of (potentially) hundreds of elements.

Of course, there are non-digital means of adjusting delays. Something as simple as having multiple traces of slightly-differing lengths connecting each antenna element to the receiver, then selecting the trace of the desired length, would do the trick (assuming the trace-to-trace crosstalk problem is eliminated), though this would mean a relatively coarse increment of adjustments and a smallish number of elements, and therefore coarse beam steering/lower gain. It would also be incredibly cheap, and if the granularity is still fine enough to achieve the steering accuracy needed, and the lower number of elements provides the needed gain... win!

Sigh...

[fahrbot-bot]

Summary is first paragraph of a 5-paragraph article. Here are the other four:

Marcel van de Burgwal's system would not need to be aimed. Instead, the antenna array would electronically "aim" itself. It is a concept similar to the LOFAR project, in which numerous antennas located across the northeast Dutch countryside are linked together to form a virtual radiotelescopy dish. LOFAR requires a lot of calculations and fast communications, as would van de Burgwal's system - that's where the chip comes in.

Instead of the usual elaborate, energy-hungry processors, his system contains multiple smaller, simpler processors on a single chip. They can carry out tasks more flexibly, and can be turned off when not in use. The system's infrastructure operates as a miniature network, in which TV or radio receivers are defined by software, as opposed to the traditional coils and crystals. The approach allows an entire computer network to be constructed over a space of just a few millimeters.

"Software-defined radio may seem much more complex, but we can pack so much computing power into the space taken up by, for example, a coil that it more than repays the effort", he stated.

Van de Burgwal also discovered that his multi-processor chip would work well for digital radio reception on smartphones, due to its low energy use. The technology is being further developed by U Twente spin-off company Recore Systems.

Re:Sigh...

[Anonymous Coward]

Actually, the summary changed "antennas" to "antennae", which is incorrect unless they plan on harvesting components from insects.

Re:Sigh...

[Anonymous Coward]

That depends on which dictionary you read

Where's the problem?

[operagost]

This does appear to be a solution in search of a problem. Today's dishes are already tiny enough to easily mount on an RV. Although, someone needs to tell Allstate insurance, because their commercial seems to indicate they believe a 25 pound dish can obliterate a carport.

Re:Where's the problem?

[Jeff DeMaagd]

I don't think DSS dishes are even 5lb.

I think this might allow more placement options, but there are likely major trade-offs. If you want your phased array antenna to allow you to place the antenna flat on the side or top of a house (or RV), then you reduce reception sensitivity to the intended satellite vs. a parabolic dish of the same area pointing at the satellite. Parabolic dishes themselves don't consume power, whereas this chip does. Having a lot of small antennas also means wiring and complexity, so I would expect to pay more vs. a very easy to make fiberglass dish and LNB arrangement. An upside though, is that if it works, this would let you instantly "point" to any arbitrary satellite without switching LNBs or moving the dish. The old BUD style dishes had a system that pivots the dish to tune to preferred satellites.

Re:Where's the problem?

[natehoy]

The problem is that the dish weighs 25 pounds, offers significant wind resistance, cannot be used while the vehicle is in motion, needs to be aimed at a satellite each time the RV is moved, and depends on geosynchronous satellites or continuous aiming with a servomotor. It's also ugly, but that's an aesthetic problem, not a practical one.

The advantage of phased array systems like this would be that you don't need to deploy and aim the dish once you reach your destination. You simply turn the system on, and the handful of flat metal pads glued directly to the roof of your RV (plus possibly a couple or three on each side if you're in high latitudes) can pick up the signal without moving anything around. The pads can be utterly unobtrusive, installed permanently, and offer no wind resistance at all.

There are no moving parts because the array is "aimed" only in a virtual sense by software. You'll still need a good bit of surface area to pick up a useful signal, but that surface area can be flat and spread over a larger area in smaller bits (you don't need one big contiguous dish, just a few squares or rectangles of surface area). It can even track a moving satellite and keep it in view (or track a moving or geosync sat while you are driving down the road).

No wind resistance when driving, no moving parts to wear out or replace. Just a few metal bits glued flat to the roof, wired to a computer that compensates for the time difference between the various signals. You could get signal from multiple satellites in different parts of the sky simultaneously, or based on which one happens to be in the clearest view at the moment, without carrying around a sky chart and signal meter or depending on a complex array of servos to do it for you.

Phased arrays are not new. It just takes a lot of number-crunching and a lot of power, which up until now has been accomplished more cheaply by hammering out a parabolic dish and aiming at a stationary target, saving all that number-crunching.

This guy's algorithm and chip design may (or may not) make it cheap enough to be practical for routine use.

Re:Where's the problem?

[MartinSchou]

This does appear to be a solution in search of a problem. Today's dishes are already tiny enough to easily mount on an RV

I would like to have satellite TV on my phone. Now then - where exactly do I attach the phone to my dish?

Secondly, while it probably won't work while indoors (can't see any satellites), it'd probably work while I'm in the garden, on the beach or on my bicycle.

There you go - we just found a problem for this thing to solve, and it only took me about 2 seconds to come up with it. I'm sure there are companies looking at this on-chip phased array antenna and going "OMG WTF BBQ, that'll solve the problems we're facing with $product".

Re:Where's the problem?

[Cramer]

The first gen AU9(?) was 35lbs. A single LNB oval dish (plus LNB) is a little more than 5lbs. The monster DISH Pro/1000 thing is 30-40lbs. (and a real pain in the ass to aim.)

Re:Where's the problem?

[AK Marc]

The problem is how to mount a dish on a moving car. How to mount a dish on a moving airplane. How to mount a dish on a stationary car and then move the car without having to take down the dish (though they have solved that with folding tracking dishes, but you must wait between turning it off and moving and deploying it and having it usable). How to mount a dish at a house where the owner doesn't want to see a dish. How to get a large dish at the needed height on the roof of a commercial building when the larger dishes require massive mounts that won't work with the building structure and the dish can't be mounted elsewhere because of the line of sight issues.

I could probably think of 10 to 100 more that are somewhat specific, but if that costed the same as a regular dish, I would see those being more popular. And if they can scale the thing up to 5 meter size, I can see businesses fighting to put them on their large flat roofs which can't hold anything near that size without large and expensive modifications to the roof and the building.

Oh, and I thought of one other little issue. You'd not need to do aiming with this, when you need to with regular dishes. That means that install costs for large VSAT carriers could be reduced by shipping the antenna out to be self-installed, rather than spending time and money sending out the trained professional required for today's installs. That would have a massive impact on the VSAT industry. And the lack of a need to ever repoint a dish in the event of a mount moving or service changing would save massive amounts of money.

Re:Where's the problem?

[grcumb]

This does appear to be a solution in search of a problem. Today's dishes are already tiny enough to easily mount on an RV.

One potential use for these would be with the upcoming O3B network of MEO satellites. Currently, the ground station design is very expensive, because the dishes need to target the next satellite coming over the horizon about once every 20 minutes. A flat panel such as this would remove the need for mechanical elements in the antenna array. Definite win.

O3B is a very interesting service to the developing world, where the odds of pulling a fibre-optic cable any time in the next decade are often close to nil.

Re:Where's the problem?

[Anonymous Coward]

I don't know if there is any application to this in the free world but in Iran having a satellite dish is illegal and you can get hefty fines as well as jail time for just owning an antenna. They usually use other building's roof to find satellite dishes, so I guess any other type of antenna design could help to obfuscate the dish.

Re:Where's the problem?

[sjames]

There are many cool applications of the chip. Receiving satellite TV on a smart phone isn't one of them. The array would still be bigger than the phone. It could be less awkwardly shaped and a LITTLE smaller than the regular 18 inch dish, primarily because it would be perfectly "aimed" while the dish needs enough margin for error.

Re:Where's the problem?

[Plekto]

Well I know for sure that the local news vans running around the city will love this technology. As it is, they have to stop and spend several minutes linking up everything. Now imagine them just parking and being online in 30 seconds. Or while still moving, even.

Re:Where's the problem?

[Kagato]

Mobile is certainly a market. But there's a lot of money spent installing and fixing DBS dishes around the world. The amount of money saved troubleshooting would be tremendous.

Re:Where's the problem?

[jpmorgan]

My parents won't switch to satellite, even though they hate their cable provider. Why? They think the dish looks ugly and don't want one on their house.

Re:Where's the problem?

[cuby]

Parabolic antennas have high gain but a very small beamwidth, hence you need to be pointed precisely in the direction of the transmitter. With an array, the beamwidth is wider.
see beamwidth: http://www.kyes.com/antenna/navy/basics/antennas.htm

Re:Where's the problem?

[Anonymous Coward]

Laser was a solution in search of a problem as well.

Antenna arrays are surely cheaper and also more light-weight than parabolic reflector dishes.

But it think the greatest thing about it (sadly not mentioned in the slashdot report) is the auto-aiming. Imagine aiming your antenna just by sending software commands.

Let's just wait until this chip has learned to TRANSMIT, not only recieve, and we have the absolutely perfect solution for spacecraft communication, on-ground as well as on-spacecraft.

imagine
(a) not having to pay millions of dollars for a 70-meter parabolic deep-space antenna PLUS a motor capable of turning the antenna with extreme precision
(b) not having to pay millions of dollars for the additional kilogramms a parabolic reflector dish is costing
(c) CONSTANT CONTACT with your spacecraft, no matter which direction it (and therefore it's antenna) is turned.

i.e. in a critical phase of ESA's Rosetta mission, during the flybuy of asteroid Lutetia, they lost contact with the rosetta spacecraft because it had to turn it's antenna away from earth to turn it's camera towards the asteroid.
OR: the voyager/pioneer spacecraft all had three different antenna systems, because the danger of losing contact with the spacecraft because of accidentially turning the antenna away from earth would have been too high.

therefore: YES, there are a lot of problems for this, especially in high-tech, but it's not a complete solution yet. it still needs to learn to _search_ for a signal by itself and auto-adjust itself onto that signal, and to transmit.

Re:Where's the problem?

[Anonymous Coward]

ummm .. that news van .. it TRANSMITS .. Not really the application this is designed for.

Re:Where's the problem?

[TheABomb]

Or you could just not watch TV while you're driving....

Re:Where's the problem?

[natehoy]

This is an RV we're (generally) talking about here. Not having to physically deploy the unit means several nice things.

First, your passenger(s) could watch TV during all-day drives if they wanted to.

Second, if you arrive in a pouring rainstorm, no need spending 15 minutes out in the rain futzing around with your dish and a signal meter.

And third, you stand a better chance of locking in to a satellite, since the unit can test all of the satellites simultaneously and lock in to the strongest one.

Of course, a lot of this has more to do with the elimination of the need for a fixed-direction antenna. If a TV operator could orbit satellites at a lower, cheaper, non-geosync orbit, they could get a cleaner signal to you with less power and less latency (think Internet over Irridium II that might actually succeed, and satellite cell phones that can actually work affordably). Your antenna could simply track the satellites and switch between them as they drop below your horizon.

Re:Where's the problem?

[Nethead]

Having hauled many of the KaKu dishes up to roofs, yeah, lots more than 5 lbs. Just the az-el knuckle is 5 lbs.

Re:Where's the problem?

[adolf]

Oh. Cool.

So it works sort of like this, except for that small detail about how it doesn't exist yet.

Wake me up when it becomes cheaper than doing it the old fashioned way.

*yawn*

Re:Where's the problem?

[Jeff DeMaagd]

I would imagine that it does vary by type. I was thinking of the standard small dish I've seen around, one or two LNBs, nothing special, never felt that heavy when I picked one up. I could only find one dish which specified the weight in the listing:

http://sadoun.com/Sat/Products/Winegard/DS4047-18-Inch+Antenna.htm

Single LNB, 5lb.

It will still work

[GungaDan]

if you connect it with Monster cables.

Been done for years...

[swfranklin]

There are a lot of phased array sat antennas on the market, e.g. http://www.raysat.com/ - TFS makes it sounds like a new idea.

Re:Been done for years...

[natehoy]

According to TFA, the "new idea" appears to be using purpose-built specialized processors and a more efficient algorithm.

Phased Array antennas

[Bruce Perens]

Phased-array antennas really do work but they are not new. The nice thing about them is that they have electronic steering, so they can steer really fast while a conventional antenna of equivalent size would take much more time to move.

The problem with articles like this (and their Slashdot introductions) is that they always come off as student makes big scientific break-through rather than student applies well-known science.

Re:Phased Array antennas

[Chaostrophy]

It sounds like the break though here is in a much cheaper controller, such antenas have been around 50 years (the first nuclear aircraft carrier, Enterprise, had one), and are available for RV & SUV use (big blob on roof, $$$).

Re:Phased Array antennas

[EdZ]

In fact they are SO not new, they were used for satellite reception back in the late 80s/early 90s.

Re:Phased Array antennas

[MichaelKristopeit 54]

who do you believe it came off as "student makes big scientific break-through" to?

Re:Phased Array antennas

[DerekLyons]

And since your typical home satellite antenna has no need of moving... this sounds like a solution in search of a problem. Doubly so since current antenna a pretty small. Shrinking them further requires either increasing their transmission frequency, or improving the amplifiers - not shifting to phased arrays.

Re:Phased Array antennas

[Bruce Perens]

If there is any breakthrough, it is that someone is working on this and not giving the results only to the military. Yet. Sometimes articles like this are advertisements for grants.

Re:Phased Array antennas

[Anonymous Coward]

Did you BOTHER to even read the summary before posting to this guy's comment?

"...now it looks like even those might be on the road to obsolescence. A recent PhD graduate from The Netherlands' University of Twente has designed a microchip that allows for a grid array of almost-flat antennae to receive satellite signals."

By not stating that he designed an IMPROVEMENT to the tech the summary blatantly implies he's the inventor to said tech. Basic English isn't rocket science. Why are you being so obtuse? Is it intentional?

Re:Phased Array antennas

[fotbr]

True, they don't need to move. Except when an ice storm loads enough ice up to move it. Or wind moves it. Or the idiot installer couldn't be bothered to point it correctly the first time. Or the neighborhood kids decide to repeatedly throw basketballs at it. Or any of a dozen other ways that crap happens and you need to re-point the dish.

Being able to more securely mount it in "roughly" the right direction, and electronically "point" the array would be a big advantage.

Re:Phased Array antennas

[Bruce Perens]

Indeed they are SO SO not new that anyone around when they were used in the late 80's and early 90's would not have been alive when they were invented in 1905. :-)

Re:Phased Array antennas

[Derling Whirvish]

Yes, but there are moving vehicle applications where a flat steerable phased-array is the superior solution compared to a movable motorized dish arrangement.

Re:Phased Array antennas

[Anonymous Coward]

And since your typical home satellite antenna has no need of
moving

Electronically aimed antenna could easily switch among satellites on demand. A given antenna could receive from multiple services, or multiple satellites from the same service. This is a large increase in capability over fixed antenna.

Electronically aimed antenna could even track LEO satellites. LEO satellites have more bandwidth due to lower orbits (inverse-square law) and also much lower launch costs.

Low cost phased array antenna would open up a lot of possibilities. Dismissing this out of hand is foolish.

Re:Phased Array antennas

[MichaelKristopeit 39]

MIGHT = MIGHT NOT, moron.

why are you so oblivious to logic? is it retardation?

Re:Phased Array antennas

[AK Marc]

Cheaper controller? I have bought sub-$100 router/switch/firewall/WiFi/NAS devices which contained a phased array. I'm not sure where the costs are allocated in that mess of a consumer product, but it can't have been any more than $99 for the phased array controller. Look for it by name - MIMO. Sure, this may be an application of the cheaper consumer-grade phased array into the notoriously expensive satellite arena, but phased array controllers can't be much when standards for cheap consumer products include them.

Re:Phased Array antennas

[Hatta]

So, how can I use phased array antennas to improve my OTA DTV reception?

Re:Phased Array antennas

[Bruce Perens]

You don't need them for this. Build a Gray-Hoverman antenna.

Actually, you should also look for other problems. Before I bought a UHF meter, I thought I wasn't getting enough signal. But the meter said otherwise. The problem was front-end overload or intermodulation swamping the weaker stations. Get rid of your present store-bought preamp, and any other amplifiers in the line, they're too noisy. Get a preamp from Research Comms, they are really pricey but worth it. Remember to order the power supply and outdoor box, too. The 9270 is good if overload is a problem, it mounts indoors and has a wired-in power supply, otherwise pick from the table here for the channels in your area and mount at the antenna.

Re:Phased Array antennas

[powerlord]

Indeed they are SO SO not new that anyone around when they were used in the late 80's and early 90's would not have been alive when they were invented in 1905. :-)

Good sound-bite (sound-byte?), but Grandmother managed to make it just fine into the early 90's and was born just a bit before 1905.

People are living longer and longer, and we're only talking about 85-90 years (heck, my grandmother used to tell us about being a girl and watching this new-fangled thing flying overhead, the airplane).

Re:Phased Array antennas

[russotto]

So, how can I use phased array antennas to improve my OTA DTV reception?

Lots of ways. Re-point (electronically) for every channel, even multiple simultaneously. Phase-cancel an interfering signal based on its direction. A more complicated system with dynamically-changing phase delays could probably reduce the impact of dynamic multipath.

Re:Phased Array antennas

[DerekLyons]

I know a lot of people with dishes, and they rarely have to reposition them. So this 'advantage' costs considerably more for very little actual advantage.

Re:Phased Array antennas

[jabuzz]

And there application to satellite dishes is not new either. A quick Google shows that such dishes are readily available in the UK.

http://www.aerialshack.com/metronic-flat-satellite-dish-with-builtin-p-1398.html

http://www.southernsat.co.uk/cart/index.php?l=product_detail&p=226

Re:Phased Array antennas

[Anonymous Coward]

That 'Squarial' you've linked to is not steerable - it still needs to be pointed at the satellite, while the device discussed here can be "pointed" in software, i.e. you can just lay the antenna flat on you roof, and as long as it's pointing roughly south and up (for the northern hemisphere), you can adjust the exact direction you're receiving a signal from by software.

Re:Phased Array antennas

[fotbr]

And I also know a lot of people with dishes, and most of them have needed it repositioned every year or two, depending on the weather. Your anecdotes don't make mine wrong.

None of which addresses the biggest issue, which is the idiot installers. Cut down on the time they require, and have a system that does a better job at the same time.

Re:Phased Array antennas

[DerekLyons]

And I also know a lot of people with dishes, and most of them have needed it repositioned every year or two, depending on the weather. Your anecdotes don't make mine wrong.

ROTFLMAO. My anecdotes don't have to 'prove' you 'wrong'. You shoot yourself in the foot quite adequately without my help.
 

None of which addresses the biggest issue, which is the idiot installers. Cut down on the time they require, and have a system that does a better job at the same time.

ROTFLMAO. This system will cost more than the time it replaces *and* doesn't do a better job than a conventional dish. You really are clueless.

RSN

[FlynnMP3]

The real news is the last paragraph of the article:

"Van de Burgwal also discovered that his multi-processor chip would work well for digital radio reception on smartphones, due to its low energy use. The technology is being further developed by U Twente spin-off company Recore Systems."

There is more money to be had from a general purpose antenna receiver in smartphones. At the very minimum, faster ROI which is what will drive the faster development/implementation into the consumer market.

What the article doesn't say is just as interesting. I'd be more interested in signal loss ratios and other engineering things. Maybe the dishes are better at what they do than what this chip can do. Still, it's nice to see promising research like this that will drive further research projects.

and how well does this work with rain fade?

[Joe The Dragon]

and how well does this work with rain fade?

Re:and how well does this work with rain fade?

[kehren77]

Exactly! Screw making it smaller. Make it weather resistant.

Re:and how well does this work with rain fade?

[forkazoo]

and how well does this work with rain fade?

Basically as well as existing antennas. Rain fade happens, pretty much by definition, in all the stuff between the transmitter and the receiver. You can't engineer something in the receiver to make it not happen because it has already happened before the signal gets there.

You can make the antenna bigger to get more signal. That's true with existing technology, that's basically still true with whizzy modern phased array systems. Ideally, the phased array stuff will result in smaller systems with the same ability to pick up signal, so a system with the same size as an existing system but newer technology will probably pick up a faded signal better.

What about LOS requirements?

[cypherstream]

When they can eliminate LOS requirements, THEN they have a breakthrough. Also, Sirius Satellite Radio has an antenna about the size of a half dollar. It works anywhere there's no obstruction of the general sky. Why do TV antenna's need to be so much bigger and point "dead on" at a very precise location of the sky. Also fix rain fade and we've got a winning product.

Re:What about LOS requirements?

[Anonymous Coward]

You will NEVER eliminate LOS requirements for high bandwidth sat links. The reason your Sirius Sat radio works without line of sight is Sirius has ground based repeaters in major metro areas for the tiny chunk of bandwidth that they use for audio

If you were do switch sat tv to this model, 1) why even use the sats anymore? and 2) if you realized the swath of bandwidth that directv's signal required, you would know there's no hole in the band plan that could accommodate it. directv broadcasts off 5 birds right now, each bird is capable of about 500mhz of bandwidth. Tell me where the 2.5ghz wide hole is in the FCC's band plan? Most metro cable plants dont even send a bandwidth this wide over their coax infrastructure most toping out at around 900mhz to 1.2ghz of bandwidth. There's a reason directv has so many more channels than cable.

I forget exactly where i read the fact, but i remember reading somewhere that if you could capture ALL of the data hitting a directv dish at any one moment, you would need a way to capture about 150-200 megaBYTES of data per second.

Another story that never dies

[skywire]

Substantially the same story has been popping up regularly for about twenty years. It's like the flying car story. It's always just around the corner, but it never reaches the market, at least not at a competitive price.

Re:Another story that never dies

[dbateman]

Never reached the market? What about the squarial from BSB in the UK in the 90s (http://en.wikipedia.org/wiki/Squarial)

D.

It gets even better if you make an array of dishes

[RichMan]

The observatory consists of 27 independent antennas, each of which has a dish diameter of 25 meters (82 feet) and weighs 209 metric tons (230 Short tons).

http://en.wikipedia.org/wiki/Very_Large_Array.

The flat surface to dish per the original article is a trick where you vary the electrical distances of each of the patches on the flat surface to shift the signals as though they were spatially received by a dish shaped surface. You can apply the same trick to dish antennas which have much better directional gain than flat patches and do a super gain antenna.

With Ham Radio...

[Anonymous Coward]

We can do EME (earth moon earth) and LOS (low orbit satellites) with hand held yagis. I don't see how this is new tech, but I'm happy it's getting more recognition.

Re:With Ham Radio...

[Anonymous Coward]

First, though I haven't done any EME, I was under the impression the only way you could possibly make EME contacts with a handheld yagi is if the other station had one of those really awesome setups. If you actually know of any such contacts with handheld antennas at both ends, I'd appreciate a link, but from here it sounds like you're confused or BSing. LEO sats are of course an entirely different matter.

Second, Yagis are not getting attention here. Phased arrays (of patch antennas, it seems) are getting attention, and more specifically, a new SDR chip for phasing them.

Without Ring TFA, it sounds like it's receive-only -- cool for satellite TV, but somewhat less interesting for hams. Still, if you can lean a 100 sq. ft. phased array against the side of your house, then electronically aim it (and keep it aimed) at the moon to hear, you can always use a smaller yagi for transmission, either by kicking more power, or hoping the other guy has a similarly sensitive receive setup.

Array info

[Caerdwyn]

A collection of links on antenna arrays at a ham radio antenna design site: http://www.dxzone.com/catalog/Antennas/Array/

It's not all about signal strength. Sensitivity these days is rarely an issue; the electronics in the receiver are excellent. Of greater relevance are polarization, rejection of off-axis noise, directivity, and the ability to reject signals from adjacent bands. There are also issues of setup difficulty, and this is what the primary focus of the design in question is.

Aiming a dish antenna is a chore, and high winds which shake a parabolic dish can cause signal strength to fluctuate dramatically. An electronically controlled phased array can, by introducing delays to various antenna elements, "steer" itself and lock onto a satellite with great accuracy (within a few degrees of the direction the array is aimed). A small antenna, perfectly aimed, will outperform a larger antenna poorly aimed, and if the antenna's controller can aim itself without physical adjustments many thousands of times per second, wind and a... coarse job of aiming the antenna are non-factors.

A military example: PAVE-PAWS, a 435Mhz missile detection array used by the US Air Force. The antennas in question are made of thousands of smaller elements (a single dipole element at 435MHz is about 35cm long), do not move, but the transmitted radar beam and the reception-aiming can be extremely precise. The more elements you have, the narrower the beam but the higher the gain.

L-band, commonly used by companies like satellite TV providers, is 1 to 2 GHz. An array of 16 log-periodic (wideband) antenna elements would therefore be 60cm square. A 4-element array would be 30cm square. Pretty compact, and if it gets rid of the most common cause of poor signal strength (a poorly-aimed dish), it's a win.

Re:Array info

[Anonymous Coward]

Phased Arrays do not guarantee being pointed at the target. The change in phase between components is discreet.
As an example, cheaper systems might use as little as 4 bits to control the phase between components. Steering the antennae by 360/2^4 degree increments gets the array relatively close but will not be as efficient as manually pointing a dish antenna.
The more expensive military systems provide a lot more discreet phase increments and can get extremely close to the target.

What's new is cheaper, lower power

[MDMurphy]

What's new isn't a phased array antenna for satellite TV, you can get them now, though they might cost several thousand dollars vs less than $100 for the small dish.

The Gizmag article mentions the new chip being cheaper and lower power as opposed to what is currently used. Besides being "flat" and sticking out a phased array satellite TV antenna would be easier to install as it could be aimed electronically rather than physically pointing the antenna. It would still need to be pointed in the general direction, but would require less fiddling with.

Got an 802.11n receiver?Then you have this at home

[RichMan]

802.11n directionality is achieved by phase summing the signals from 2 or more dipoles.
Yawn.

Oh yeah the patent for 2 or more phase locked receivers on one chips is pretty old. So even getting it onto one chip is not new.
http://www.freepatentsonline.com/7636554.html
A MIMO radio transceiver to support processing of multiple signals for simultaneous transmission via corresponding ones of a plurality of antennas and to support receive processing of multiple signals detected by corresponding ones of the plurality of antennas. The radio transceiver provides, on a single semiconductor integrated circuit, a receiver circuit or path for each of a plurality of antennas and a transmit circuit or path for each of the plurality of antennas. Each receiver circuit downconverts the RF signal detected by its associated antenna to a baseband signal. Similarly, each transmit path upconverts a baseband signal to be transmitted by an assigned antenna.

Flat is the old black.

[Greger47]

Granted, they are not phased array so you need to aim them, but flat Ku band satellite antennas have been around for over a decade around here. Here is a random example a quick googling turned up: http://www.techradar.com/reviews/audio-visual/digital-tv-receivers/sqish-selfsat-h10d-420191/review

/greger

Not at all new

[Rising Ape]

This isn't new, BSB here in the UK had a flat satellite receiver which they called the "Squarial". It was a phased array, like other people have said.

Now, if it could be electronically adjusted to pick up different satellites without having to physically move it, that would be interesting. I believe some military radars do this.

Re:Not at all new

[Rising Ape]

OK, that'll teach me to not RTFA properly. Apparently it *can* be electronically adjusted.

Re:Not at all new

[Andy Dodd]

So can the TracVision units which have been on the market for a few years.

Not new at all

[Andy Dodd]

Phased arrays for DirecTV reception have been on the market for at least a few years. Here's one:

http://www.solidsignal.com/pview.asp?mc=06&p=KVHA7&d=KVH-TracVision-A7-InMotion-SUVMiniVan-DIRECTV-Satellite-TV-Antenna-System-(A7)&c=Satellite%20Dishes%20for%20SUVs&sku=

Supposedly the student has developed a signal processor that will reduce power consumption and/or cost, but the article is REALLY slim on details as to how they did this and whether they really have made any significant breakthroughs beyond what's already there.

Terminology and Impact

[Anonymous Coward]

Uh, insects have antennae, radios have antennas.

The advantage of the system described by OP is that the satellite antenna system not only doesn't have to be a curved piece of metal up on a special mounting, it also doesn't have to be physically aimed closer than a quadrant of the sky.

The flat antenna would likely be larger than today's small dish, but it also could be just a rigid frame nailed to a roof. The news article is VERY unclear on how this works. Chances are it's some variant of phased array synthesis that can be done cheaply due to dedicated processors on the chip being described. The key word is "cheaply," as in consumer, not military, prices.

@cypherstream, rain loss and Sirius

No, the new antenna won't affect rain loss unless you're willing to install a bigger one. Sirius uses such a small antenna because a) their satellites put out humungo RF power, and b) in large cities they use ground-based repeaters to beat the "street canyon" effect. Google "link budget" for more.

Re:Terminology and Impact

[Lumpy]

Sirius Satellites Radiosat 1 through Radiosat 3 fly in geosynchronous highly elliptical orbit (Tundra orbit) in a 24-hour orbital period. The elliptical path of its satellite constellation ensures that each satellite spends about 16 hours a day over the continental United States, with at least one satellite over the country at all times. The orbit allows the satellites to broadcast from directly overhead the continental United States, avoiding the problem of large buildings or objects blocking the signal and requiring a much smaller terrestrial repeater network than does sister network XM.

They are also not higher power, they are transmitting a lot less bandwith than a TV bird is. lower data amount = lower power needed.

Finally their orbit makes them a lot closer to the earth than a geostationary orbit... giving them a simple boost from less distance and the advantages of the inverse square law.

Re:Terminology and Impact

[snowraver1]

1) Your first paragraph was jacked from wikipedia.

2) Sure it takes more power to transmit over a larger frequency, but if you have a device transmitting across 10Mhz @ 1 watt, it will take more power than a device transmitting across 20Mhz@1mW. Just because you are transmitting a large amount of data (or small) doesn't mean you can't have high power.

3) When the Sirius satellites are actually transmitting, they are actually FURTHER out than a geostationary orbit. It's actually kind of neat. They are pretty far out when they are "hovering" over Saskatchewan which causes their relative movement to slow (the earth actually rotates faster for a bit creating a 'loop' in the orbit), and allows them to spend more time over North America. As they head south, they get closer to the Earth so that they can quickly fly over South America and get back up North and start transmitting again. This is what creates the 16 hours a day over our head. If the satellite was at a constant height, acheiving 16 hours would be impossible.

Re:Terminology and Impact

[Lumpy]

1 - EXACTLY! I'm not going to retype something that is clearly spelled out. This is slashdot, not my PHD dissertation... Or my weekly article in Wired...

2 - You are correct, but that is NOT what I said.

3 - The Articles I found about it are wrong then, all info I could find mentioned they were closer. got any links to details on that so that I can read more on it?

Re:Terminology and Impact

[snowraver1]

You can watch it in action with a google earth plugin, but you have to fight with the camera to see what is going on. I know I have seen a good real-time animation before, but I can't remember where. It might have been J-track.

Power spectral density

[Andy Dodd]

The amount of spectrum bandwidth required to transmit a few hundred audio channels is a fraction of what is needed to transmit a few hundred TV channels.

So given a constant amount of power available, the power spectral density when transmitting audio only is significantly higher than when transmitting television.

Also, Sirius uses satellites in Tundra or Molniya orbits (I don't remember which), which are geosynchronous, but not geostationary.

Yes - RTFA!

[Roger W Moore]

Raw size does matter here. A larger receptor is better.

If you RTFA (yes I know it is Slashdot but hope springs eternal) you'll see that the system uses a GRID of flat antenna which it combines to simulate a larger antenna. By altering how the signals are combined i.e. the delays between them you can "point" the antenna at different sources. Hence you not only have a large detector from combining several smaller one but you can also point the thing without having to mechanically move it. It's brilliant idea and one that radio astronomers have been using for quite a while.

Squarial

[Anonymous Coward]

Sounds a lot like British Satellite Broadcasting's Squarial from the late 80's / early 90's - http://en.wikipedia.org/wiki/Squarial

Size matters but...

[Comboman]

Yes, size matters, but an array of small antennas can have the same effective size (or larger) than one large parabolic dish and still take up less physical volume (it could lie flat against your roof). The bigger advantage is that such arrays can be steered electronically so you don't need to do fine mechanical adjustments to a dish to aim at the satellite and can even aim at a different satellite without any mechanical gears or motors.

squarial

[Anonymous Coward]

been around for a while.
Developed by ERA Technology, UK.
Used to be available for satellite reception.
Half a dozen pieces of injection moulded plastic with vacuum deposited copper.
Quite elegant not to mention clever.
I think it was sold by BSB (could have been Sky though) as the way to get access to their material.
It has been investigated by other vendors.
O

ship radar without moving antenna

[kubitus]

cheap satellite transmitter antenna-steering for 2-way comm with non-geostationary satelites

cheap weather radar

- just to name a few applications beside simple satellite reception.

- It is not a ground breaking technology - but also computers were known before the PC came!

what... would be the point?

[Anonymous Coward]

there really hasn't been anything worth while on TV (dish, ota, cable, ip, you name it.) ...

Phased array are physically robust

[shis-ka-bob]

Any directional antenna needs to be aimed. Bump it an you loose the signal. with a phased array, you can combine the signals from each 'antenna-let' to act like a dish as far as signal strength is concerned. If you want to connect to multiple satellites, you don't need to move anything, you just have the signal processor combine the signals with different phases to lock into a different direction.

Recent graduate with PhD != student

[shis-ka-bob]

The article states that this work is being done by a recent graduate in a PhD program. That doesn't make him a student. A young Ph.D. has developed a low power controller for a phased array radio receiver. This is a nice piece of kit with a range of applications in mobile devices. It builds upon technologies that have in the past been dominated by defense contractors. Our young Ph.D. is helping to make this technology more accessible to the 99% of the world who are not spooks. This is all good, even if it is not groundbreaking.

If only somebody would invent a mobile radio phone

[shis-ka-bob]

Oh wait, I have one in my pocket.

Sweet! Wake me up when they're here.

[Anonymous Coward]

Until then, gotta use what's around, not what might be.

Yes, it does work.

[rickb928]

This is not new or even especially clever compared to some antenna designs. And it does actually work and has benefits.

Aegis cruisers use a phased-array radar set that solves a multitude of problems - flat panel does not need to be physically articulated or rotated, it 'aims' virtually instananeously, allowing the system to track multiple targets with high precision, and I bet it consumes substantially less power than a moving dish or other types of antennae.

Replacing various reflectors with an array, one managed by a dedicated logic device, sounds like a very cleaver solution. Among the advantages:

- Flat-panel mounting on the side of your building. Neighbors might like the look better.

- Simplified aiming. Let the chip make the adjustments. Might even get an aiming aid built into the array some day, making ti a lot simpler than it has been.

- Possibly, just maybe, this would be a dual-purpose antenna, supporting satellite video and neighborhood WiFi or the equivalent. That's a play some ISPs might be interested in. Probably not your cable company.

The most obvious disadvantages to me are potentially fragile electronics and longevity, same coin different sides.

But this stuff does work.

Now to get it micro-sized to fit into a phone.

Re:Yes, it does work.

[monkyyy]

would it work on a phone?

but anyway i hope some bight eye isp trys to use this to make internet faster and cheaper

Re:Yes, it does work.

[rickb928]

Well, phones mostly use arperture antennas, which are very good. The arperture on an iPhone4 is the slot you short out with your left-hand palm. I stopped studying antennas a long time ago, before these came into popularity, so I'm still fascinated by them.

Wireless ISPs would find arrays useful to improve range, but the expense might make them more useful for higher-value links, like business connections and backhaul. At the extreme of utiilization, an array could allow a mesh to also be self-healing, re-focusing to a 'good' link and continuing operation.

But none of that makes anything cheaper...

This is a big improvement over parabolic dish ...

[Anonymous Coward]

but it certainly isn't new.

A phased array is electronically steered so you don't have to physically point the array at the satellite like you must with a parabolic dish.

If you have a flat phased array antenna it can be mounted flat against a mounting wall and electronically steered. This is better than having a big dish sticking out of the side of your house or roof. It also helps protect then antenna from high winds. As long as the satellite is in view of someone standing with their back against the mounting wall the array can be digitally steered to focus on the satellite.

A single phased array antenna can be simultaneously steered toward many satellites at once if you have the computing power behind it.

Depending on the implementation electronic arrays can adaptively/on-the-fly suppress background noise and interference as well as interference from other satellites that are at small angular displacements from the one that you want to focus on.

An article about that from 1970

[Casandro]

http://www.bbc.co.uk/rd/pubs/reports/1970-27.pdf
Now add variable delay lines and there you go.

Available now, for your RV.

[Animats]

You can get a phased-array receive antenna now, to receive satellite TV on your SUV or RV while driving. This has been a common military technology for decades.

One for stationary use could be simpler. The mobile units have a full GPS/inertial/compass setup, so they know where to aim as the vehicle moves. A stationary unit doesn't need all that. It can just scan around after installation, find the desired sats, and store the direction.

Re:Got an 802.11n receiver?Then you have this at h

[butlerm]

The sad thing is that some people consider this an "invention". Just another random giveaway by people who make it their life's work to destroy the U.S. economy.

hmm..

[Fuzzums]

Not having read TFA, I bet it has something to do with synchronising the signals of the different part of the array...