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5 km Range Commercial Wi-Fi Available
prostoalex writes "Japanese company Maspro Denkoh will start selling transmission systems, enabling WiFi signal over 5 km, Network World magazine reports. From the article: "There are two types of antenna: one is a tube-shaped model about 40 centimeters long, and the other is a much shorter and square-shaped model. Combining two of the tubular antenna -- one on each end of the link -- will result in a transmission distance of about 5 kilometers while one of each antenna will work on distances up to 2 kilometers and two of the compact antenna will be fine for up to a kilometer, the company said.""
The world record for a wifi connection is 125 miles. whats 5km really going to achieve? All I can really see is a bunch more hackers gaining access...
This'd be great for home, too, (if it's reasonably priced) because it would guarantee the highest bandwidth is available throughout the house, without any dead-spots, i.e. my wireless won't have to step down to 1mb/s when I'm at the other end of the house.
If this was $5,230 cheaper, and if the FCC wouldn't come after me with a sawed-off shotgun, I'd probably get one of these.
Reality test... am I dreaming?
All these next-generation long-range wireless specifications are starting to confuse me. How many different wireless cards will I need to use all the different technologies, and will they all be integrated into my laptop?
Instead of the typical "5 Kms" or assorted bad notation usually found on Slashdot.
Can it serve decent speeds?
I don't think anyone will care if it isn't at least half the power of broadband with a reliable connection.
I would say that this article is nonsense, because it doesn't touch on whether or not it can actually scale to meet commercial demand, but that would give the impression that I didn't read the title, that being [...] Commercial Wi-Fi Available.
On top of that, the summary doesn't even say where this is available, and whether or not it will be elsehwere. I'm left to assume this is in Japan, because it's a japanese company selling the service.
What gives?
It's long been common knowledge that Wifi can travel over long distances. If you have line of sight transmitting any type of radio signal over long distances is relatively easy. Actually someone has already one-upped this Japanese company - These guys transmitted a Wifi signal over 125 Miles!
Netbooks, they come with Linux or a $3 copy of Windows. Either way, Microsoft loses.
Now I can leach off of all my neighboor's networks. We thought American's not using the wep or wap was bad now...just you wait.
Perhaps the limits on transmitter antenna gain are less strict ... IN JAPAN!
Whenever I hear of a story like this, I hear about potential fcc problems. I have a question though, can anyone tell me how the hell they would ever find out? I know that amplifying signals beyond certain specs is illegal, but I have yet to hear an explaination on how they could 'track you down' and chop your nuts off? Ideas?
Trango, Motorola Canopy, just to name a couple of proprietary solutions. Hell, I've even made a 16+ mile link with 802.11b SmartBridge radios. How do you think WISP's can go into and stay in business?
Pringles can antennas already delivered that back in 2001... Now, if there would only come someone along to pick up these pesky crumbs.
Windows is like decaf - it tastes like the real thing, but it won't get you through the day.
How exactly is this new? I've been using a fixed wireless ISP for well over a year now, and they've been in the area for at least two or three years before I started. Right now, I'm at 12km+ range from the main antenna and getting speeds comparable to local DSL at moderate range from a switch.
Unless this new system is *dramatically* faster than what I've got now (Motorola Canopy), there's really no point.
Since japanese 802.11 regulations limit output power of base stations and wifi cards to like 10x less than the same equipment in USA.
Its typical for wifi access points bought in Japan to have max range of 20-30meters with line of sight. LOL.
As others have pointed out, sending a WiFi signal over distances greater than 500 feet is nothing special. I worked for an ISP in 2001/2002 that was doing wireless Internet service. At the time, Verizon did not give a rat's ass for doing DSL there, and the local cable company couldn't find their ass with GPS unit and a flashlight, so they didn't matter either. The longest distance we did was 15 miles, that was through high voltage electircal transmission lines (125,000 to 250,000 Volt range ones) and over a sizable lake.
5Km. Whoopiee.
5 kilometres? All they are selling is a cheap yagi antenna and a cheap-as-free access point slapped onto the back of a network-enabled CCTV camera. You can build one from off-the-shelf components for less than $500, and that's Canadian dollars. Sure, you can up the cost by adding 'features' like CCD imagers instead of CMOS ones, a heated housing will run you another few hun, and if you want pan/tilt/zoom, that adds another grand. But fifty-two hundred bucks? Good grief! Furthermore, 5 km is nothing, as others have pointed out already. With two 12db yagis and standard 35mW gear, I've shot well past that. Yeah, the Pringles Can would do 5 clicks no problem. And their square-shaped one would have to be a 5-or-9db patch, again nothing new. So I can't see why this was even written about, or how it qualifies as news, since it's not really revelutionary or innovative. Maybe it's just me, being jaded. Or maybe it's 'cause I've worked too close to a few 200mW radios. I have heard that microwaves can be harmful.
"Apparatus dignosco occultus, satis non supernus."
... so desu - this is why you haven't been able to find a can of Pringles in Japan for the past two months!
"Win treats sysadmins better than users. Mac treats users better than sysadmins. Linux treats everyone like sysadmins."
Anyone have any info on power requirements or weight on this equipment?
These antennas seem interesting, but the price tag is a bit of a downer. Can someone post a link or two to some websites with instructions on how to make yourself a good wifi antenna, for cheaper?
802.11b with parabolic grid antennas is possible up to 20 miles, if you get it high enough. Smaller anetnnas can easily go 5 miles at 11mb/s. This has been around for 5+ years, why did this story get posted?
It would also broadcast your network 4.9 miles more than you need...
How do you expect an antenna that has a 5km range to exceed 4.9 miles? That's half again farther than it what it's range is.
Repeat after me:
KILOMETERS ARE NOT MILES!!
KILOMETERS ARE NOT MILES!!
KILOMETERS ARE NOT MILES!!
I have been using a WiFi ISP for about 5 years now. And I am over 5 miles from the AP. A flat panel antenna with the tranceiver at the antenna. Cat 5e from the antenna to a router in the house. The antenna is transparent to me. They offer me T-1 if I want to pay for it.
I'm sure it's capable of large data transfer rates, but I bet the latency is terrible.
I'm agneglectic, too lazy to care if there is a God.
What you need in order to move arround in hour house connecting to an AP is an omnidirectional antena (a pigtail that broadcasts in all directions.) This are directional antenas, that is, while the omnidirectional antenas cover 360 degrees, this only cover an specific range (it differs, it's arround 25 degrees for yagis, for example), but they have to be pointed to the other antena, and they require a line of sight.
WTF am I doing replying to an AC at 5 A.M on a Friday night?
across 5km, Then post something under this comment. A system that can talk at 50Mbit+ at 3-5km ranges with power draws in the 5W range and low weight is something I would be very interested in hearing about. If you can post a web page link that would be good. A system that supports 802.xx standard is preferable.
If you measure area of your home in units of KM, then YOU THE MAN!
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Give me LIBERTY, or give me a check.
Correct me if I'm wrong, but wouldn't you start to run into increased latency issues over such a connection? 5km at 300km/ms means that you're talking, um, 0.016ms of travel time each way, per packet. While that does not seem significant, that's assuming perfect conditions (and my ability to do math in my head), and that could build up in the case of multiple transactions. Of course, considering that you're talking a minimum of about 30ms latency to any remote server, I guess it's irrelevant. Ignore me. :-)
My Systems
Such speed-of-light latency would exist, as you say; and would be irrelevant due to other factors, as you say. What you seem to be missing is that that latency is present for _any_ kind of link. In fact, the speed of light in fibre (just to take as an example one of the more likely convential signalling media) is slightly less than the speed of light in a vacuum you used in your calculation. Ain't no way bits'll get from point A to point B faster'n light.
This is just a random press release from a company selling boring old wireless kit. There isn't anything special about getting 5km of range with off the shelf wireless gear,
If anyone cares the math is not that hard to follow:
You take the transmitter output power, subtract any loss in the cable between the transmitter and the antenna, add the gain of the anteana. http://db.osoal.org.nz/eirp-calculator.html
Then you have to subtract the free space loss of your path ( the loss you get by putting the signal across the air ): http://db.osoal.org.nz/freespace-loss-calculator.h tml
And finally you add the recieve gain of the receiving antenna, subtract the loss from the cable on the recieving end and compare with the receive sensitivity of your wireless receiver. I have bundled the rest of the calculation into this bit of javascript.
For example, if I have two 2.4ghz radios that output 15dbm (32mw) that have a recieve sensitivity of -83db that are in waterproof boxes on the antenna mounting connected to two 22db antenna's 5km apart very roughly.
15db - 1db + 22db = 36db or ~3981mw (just under the 4 watt max).
- 121.65db for our free space loss
+ 22db - 1db = -64.65
-64.65 is the strength of the signal received at the other end, fortunately the receiver has a receive sensitivity of -83 so we are in business. There is a link margin of ~19db to account for a little bit of noise, fade, solar flares, alien abductions etc.
If you want more range, increase the power of the transmitter or the gain of your antenna. The government limits ( 4 watts for 2.4ghz, 250mw for 5.3ghz and 4 watts for 5.8Ghz in New Zealand ) are going to determine your maximum range barring some magical new wireless gear that has a better receive sensitivity.
I am a lawyer and this constitutes legal advice and I shall indemnify you against any losses arising from taking it.
I can make a 50km link using a night and day "top of the line" camera http://newsite.pagecomputers.com/store/product.asp ?catalog_name=Security+Devices&category_name=87g87 c453s1852&product_id=691230
...and that includes instalation!
0011 1111 0111 1010
Then what?
Reminder: Apple owns 1/255th of the internet.
I may the only person worried about this, but is there some sort of risk with having radiation exposure? I assume if 5-20 km (judging from other posts) range wireless is practical at reasonable prices and speeds, we're gonna have wireless companies competing much as cell phone companies do now. Is there are risk with 2-3 cell company towers and 1-2 wireless Wi-Fi towers blasting radiation at me? 24-7, 365? I mean, it sounds like that's where we're headed in some cities or even select suburban areas.
Why do vendors focus on stronger transmitters, when that just results in greater potential for human brain frying. Imagine all your neighbours in a 5 block sky scraper community all sitting at home with 5KM transmitters! YIKES!!
It is just as effective to create better receivers, that could for instance listen to signs from up to 5KM that even in large clusters would not fry your brain.
Just a thought.
No trees were killed in the making of this post; however, many trillions of electrons were horribly inconvenienced.
... I will be able to realize my dream of war-sitting. About time, too, with gas prices getting so high.
I know looks like this It is WLE-HG-DA(Japanese) and WLE-HG-DYG(Japanese)
You are correct that latency is an issue. For 802.11 especially, since each packet is acknowledged individually before the next one is sent (imagine TCP with a fixed window size of 1), you add 1 round trip time to the time to send each packet (at 11mbps, a 1500 byte packet takes about a millisecond and a half, and the acknowledgement takes a few hundred microseconds, so this isn't really a big performance killer).
Another effect, though, is with transmission timeouts. Suppose station A sends a packet, and begins waiting for a reply. Station B sends an ACK. Normally, station A would have priority to send the next packet, since it only has to wait 10 microseconds, versus station B which must wait 50 + 10*R (where R is a random number from 0 to 31). Unfortunately, with a large propogation delay and a small value of R, station B might assume the channel is free and send a packet (a TCP ACK, perhaps) before the second packet from A arrives, resulting in a collision. But that only happens at distances over about 5 miles I believe. Caveat: I haven't tested this effect myself, so I could be wrong in my interpretation of the spec.
Even worse is if the stations are so far apart that a transmission times out before an ACK comes back, but that requires much larger distances (I think it's somewhere around 60 miles, but I could be off by quite a bit on that one).
Just as a FYI, I currently use a wireless service that is supposed to do 1500 down and 382 up.
Now, I live in Billings, MT and the weather around here isn't exactly great some times. Yesterday
we had 9.08" of snow, my internet went down, along with power for about 2 hours, and to top it off
the TV stations went west on some channels. After about 13:00 today everything cleared up.
I will be switching to DSL via Quest, and Direct TV at some point.
My point? Wireless access is great "if" the weather is fine, but otherwise it pretty well
sucks! Get some snow, and extreme cold temps, and you're just plain and simply grounded.
Life was hell, then I discovered Linux...
That would be hard to do unless they are exceeding power or gain limits, or deploying a large number of such devices, since part 15 rules do allow use of non-approved antennas. (I am not a lawyer or an RF engineer, so take this with a grain of salt.)
The wireless access point wasn't homebuilt. What you are doing is modifying commercially manufactured equipment specifically to transmit with power densities greater than what are allowed under part 15, thereby voiding the part 15 statement of conformity and eliminating your authority to operate the equipment. Even assuming that we would consider this wireless setup homebuilt, it still would not be covered under this exception because intentionally modifying equipment to transmit outside of FCC emissions standards does not meet the requirement that "the builder is expected to employ good engineering practices to meet the specified technical standards to the greatest extent practicable." And anyway, the exception is for stuff that isn't easily measured without equipment like a spectrum analyzer, like spectral. It is pretty easy to model an antenna and measure transmitter power. Radiated power is easy to measure. The FCC would hold you responsible for not even taking the most basic steps to determine whether or not you are compliant.
I was not suggesting that anyone do any such thing (in fact I explicitly said that the FCC could come after you for exceeding power or gain limits). It is quite easy to match an antenna with a wireless card such that that particular combination has not been FCC certified, yet they are within FCC limits. The limits for point-to-point links in particular are quite liberal and difficult to exceed without an enormous antenna and/or high power transmitter.
It should go without saying that if you don't know how to verify that you are within FCC limits, you shouldn't be mixing and matching antennas or amplifying your signal.
http://www.proxim.com/products/bwa/multipoint/MP11 -R/
This is their cheap-end stuff, but it will do Point-to-Point, Point-to-Multi-Point. I've worked with it up to 6 miles over land. 60Mbps theorhetical throughput, 30-50mbps can be had with multiple TCP connections. It can run on the 2.4, 5.3, 5.4, and 5.8Ghz bands.
Proxim has stuff that will do strict point-to-point up to 1.5Gbps on the unlicensed 60 Ghz spectrum
From what I can tell it must be something like this complete system for monitoring on a farm (Japanese). Maspro also sells home security video monitoring systems using some of the same components it seems. The article was a bit weak and since I haven't been to CEATEC today I can't tell you for sure but I'd be quite surprised if they are enjoying a 1000% markup like all the other slashdotters expect. That, plus it will "just work" and be durable, etc. Take a look at their export catalog (click on pdf link) if you are interested in evaluating the company's offerings. (their English is a little wierd though..)
Now the whole neighbourhood can watch me download porn if I forget to turn encryption on!
"Reality is merely an illusion, albeit a very persistent one " -Albert Einstein
You can get 3mail system.
;-P
WLE-HG-DYG:$219.99 * 2
WLE-CC5:$54.99 * 2
WLE-LNC:$24.99 * 2
WLA2-G54C:$79.99 *2
Total:$759.92
And, if WebCam, Power, and some options are added, it is perfect!
So,You must buy
Would you really want to sleep in the same room as an ultra high gain wifi antenna? I have (probably unfounded) concerns about upgrading my B to G as i sleep 100cm's away from the idea trasmitter location.
1) Clever Sig 2) ????? 3) Profit!
They are talking about doing wireless over 5km distances when things like Wimax hardware is already doing 20km + or -. There is a company in Knoxville, TN and also in Phoenix, AZ that has installed and is starting to sell this extensive wireless service. http://www.wisight.com/ If I'm not mistaken, the Wimax products offer 802.11G speeds at much great distances. So what is the big deal about this technology listed here.
Wow, the invented the Yagi. Stop the presses.
I really hate slashvertisments.
It's better than sleeping next to a regular access point. The whole setup still has to conform to signal strength regulations, which limit field strength by giving the power that an isotropic radiator would need to produce an equivalent field strength in the part of the volume you're looking at. See, a directional antenna produces its field only in the direction of the receiver, where an isotropic radiator (something like a regular AP antenna) produces the same field strength, but all around it, not just in one direction. A directional antenna puts out _less_ total energy if it conforms to regulations. If you're not sleeping in the path of the directional link, next to no "radiation" goes through you. And why would you sleep in the path? You're a bag of water after all: you'd shield off a lot of the energy that you want to reach the other side of the link.
The article describes combining the two antenna - one on each end of the link. Does anyone know if commercial manufacturers have looked into drastically varying the standard antenna shape or material. In my line of work, I study genetic algorithms and know that GAs have been used to design space antenna (http://illigal.blogspot.com/2005/01/corkscrew-sha ped-space-antennas.html) that are far more effective than current designs.
The noise floor in any city is just way to high to use 2.4 units with any sort of reliablity.. sure maybe 5 yrs ago this was fesiable but today.. with every laptop having 802.11b/g, all those Linksys/Dlink units flooding the market there is way too much interference.. the frequency levels are limited.
As an WISP, this is the exact reason we are ripping out all the 2.4 equipment, it's pretty much useless now.. you can only get a reliable like like 500ft from a tower (which is pretty shitty). this is amped and on a parabolic dish antenna.. it's crazy how crap the spectrum has become.
-b
What happens when a few WiFi nodes are positioned in the line of the narrow AP beam? Do they progressively block the signal to the next nodes in line? How many nodes can line up behind each other to receive the signal? Just one, for a mere "PPP" connection?
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make install -not war
http://www.oreillynet.com/cs/weblog/view/wlg/448 Hmm... A tublar antenna on both ends... Sounds familiar...