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802.11ah Wi-Fi Standard Approved (networkworld.com)
alphadogg writes: A new wireless standard that extends Wi-Fi's reach down into the 900MHz band will keep the 802.11 family at the center of the developing Internet of Things, the Wi-Fi Alliance announced today. 802.11ah, combines lower power requirements with a lower frequency, which means that those signals propagate better. That offers a much larger effective range than current Wi-Fi standards, which operate on 2.4GHz and 5GHz frequencies, and lets the newer technology penetrate walls and doors more easily.
If you have flexibility on frequencies you gain the best of all worlds - 900 MHz for maximum range / minimum bandwidth, up to 5 GHz for minimum range / maximum bandwidth.
Shiny New Australia.
That's the key question: Unless you have an available open access frequency band, this standard is just wishful thinking instead of a new product.
The current allocations in Europe (http://www.erodocdb.dk/docs/doc98/official/pdf/ERCRep025.pdf) covers all of 890-942, 942-960 and 960-1164 MHz, with usage mostly cell phone, radio-navigation and broadcasting.
Terje
"almost all programming can be viewed as an exercise in caching"
Tin foil works against 900MHz right?
The bitrate for HaLow will (initially) be 18 Mbps max (source: Computerworld and a dozen other websites).
But the intended purpose range is IOT, and I don't see refrigerators, light switches and thermometers needing more than that.
(Insert famous "640 K should be enough for everyone" quote here).
I'm okay with this. Long range, low bandwidth. It might be useful for fairly remote devices that just don't have a lot to say. Some folks are disturbed about the possibility of interference with other devices on this band (mobile mostly) but presumably the FCC did their job (yea, large values of Assume in that Presume, of course). I don't think it is going to get a lot of use so I don't think it is going to much matter. It will probably have a lot of value in the industrial world in terms of remote sensing. Not so much for the home.
"...lets the newer technology penetrate walls and doors more easily."
Which is good if you live in a forest but won't this increase congestion problems in densely populated areas?
blindly antisocialist = antisocial
Don't worry, the 900MHz is not going to improve on throughput, rather on coverage.
For most of us it's actually more interesting with the 5GHz band due to more space/bandwidth. Realize that the WiFi band on 5GHz is over 600MHz wide while the 900MHz is 274MHz. Lower frequency band also means that the throughput may be lower while the covered area per access point can be larger.
If builders built buildings the way programmers wrote programs, then the first woodpecker would destroy civilization.
Here's a list of what 900MHz frequencies are available in each country
http://meshplus.com/?qa_faqs=i...
Are you just applying the Coase Theorem? It requires that the spectrum be regulatory property, auctionable to the highest bidder. But WiFi is successful precisely because the spectrum doesn't offer the prospect of legal exclusivity. WiFi succeeds because nobody can siphon off much of the wealth generated by each individual using the spectrum. The Coase Theorem falls apart when you try to license usage to each individual because the transaction costs are enormous, and the network effect weak; it's much more efficient at that scale to rely on interference (such as it is) and technological advancement to broker/mediate/allocate usage rather than relying on contracts and money.
So we return to the dilemma of who is going to pay for it. You would either need the government to realize that it should release the spectrum from government imposed exclusivity, or you would need a consortium of WiFi vendors to pony up the cash to purchase and release the spectrum themselves. The latter is unlikely because monopoly rents on the spectrum are likely greater than any consortium could earn in selling equipment and services. The open-spectrum consortium is unlikely to be able capture nearly as much value from the spectrum as the monopolist could, even though the overall wealth generated by open spectrum is much greater. It's possible it could--a smaller fraction of a larger pie can easily be greater than a bigger fraction of smaller pie, but I doubt that's the case here. That leaves option #1, or maybe a mix of #1 and #2--the government sells the spectrum to the consortium, even if the consortium isn't the highest bidder.
Lets see I already have on IoT radio in the ISM band, another in the 2,.4ghz, one at 345mhz, some sensors running a send only at 433mhz, and yet another that can run in 433/868/915MHz then add in 802..11ac in 2.4 and 5ghz. I realy do not think I need more bandwidth for my IoT gear. I need a standard for the end devices and a home controller aka things that should be designed to last for decades vs thing that should be regularly updated. The only real good thing I see from this is your average consumer gateway will have a radio that connects to our IoT devices and the encryption is stronger than what we have seen so far.
No sir I dont like it.
So basically these devices will never be sold in my country (Finland), since the 900Mhz band is reserved and used for LTE by 3 different carriers here.
Strange commentary about your menses aside, there are valid applications for internet-connected refrigerators. Whether you can imagine them or not is another matter all together.
How about a refrigerator that knows its own inventory based on RFID tag scanning, and can automatically add items to your grocery shopping list when inventory is depleted? All of the parts to make this happen are there now. If you buy your food at a store that has embraced RFID. the part you may be missing is the smart fridge.
But none of it is relevant to this article; your refrigerator is going to have access to conventional WiFi when the time comes. This is much more likely about things like connecting municipal signage & traffic control devices, letting people at bus stops know how far away the bus is, etc. (or more likely smart adverts at the bus stops). Existing WiFi protocols are impractical to implement for devices that are rather spread out like this, and which don't require the kind of throughput that your mobile device or laptop would.
No, it's a myth. If your 2.4 GHz radio had an antenna the size of your 900 MHz radio antenna, the performance would be the same. But because the 2.4 GHz dipole is smaller, the 2.4 GHz range is less. But it has to do with the antennas used, not any propagation phenomenon.
Resonant dipole antennas are constant-gain antennas, meaning that their gain is constant with frequency, while their effective area varies inversely with frequency squared. There are also constant-aperture antennas, in which their effective area is constant with frequency, while their gain varies. A parabolic dish antenna is an example of the latter; its gain varies with the frequency squared. If you take two parabolic dish antennas, fit them with 900 MHz feeds, and then take the same dishes and fit them with 2.4 GHz feeds, you'll find that the 2.4 GHz antennas have (much) higher gain and the resulting system, much greater range than the 900 MHz configuration.
It's also possible to set up a link with a constant-gain antenna (e.g., a dipole) on one end and a constant-aperture antenna (e.g., a parabolic dish) on the other. In this case the two effects cancel out, and the user does not see a difference in range between the two frequencies.
You'll find, if you actually do this experiment, that it does work this way -- regardless of whether the path goes through a forest, a house, or both. It's physics, period.
My fridge is networked, so is my chest freezer in the basement. I have an ESP8266 in each reporting the temperatures and if it's running the compressor or not for power consumption graphing.
It allows me to get an alarm if the temps rise or if the compressor stays running and does not shut off.
Do not look at laser with remaining good eye.
Indeed antennas do have a great impact on communication, but propagation includes how the signal interacts with the environment. Atmospheric absorption is very different at varying frequencies. In particular water absorption change very quickly at these frequencies. 2.4 GHz was "given away" to the unlicensed ISM bands because it is so highly absorbed by water that it was considered as useless for long range communications. This is why microwave ovens use 2.4GHz. Also scattering/back scattering and interaction with reflectors/surfaces at a given size changes with wavelength. Generally, the lower the frequency the better the range at a given power at the cost of lower bandwidth.
What about the effect of diffraction around obstacles?
900Mhz has a wavelength of 30cm, compared to 5cm for 5Ghz, so I'd expect them to diffract around typical household corners differently...
Of course 900 MHz has better range, if one is using dipole antennas. The point is, the apparent difference in range is due to the antennas used, not some intrisic property of the propagation medium.
Not just the antennas, but the medium as well - because the medium is not vacuum or free air - it includes obstacles.
(Free air, below the ionosphere, DOES selectively attenuate SOME frequencies, but all those we're talking about are in a "window" of transparency, so that's not the issue.)
A tree screws up 5G but not 900M? Scale it (including the size and thickness of its leaves and the lengths of its molecules) up by a factor of 6 and it will be a problem at lower frequencies as well. 900M goes through a wall better than 5G? Make the wall 6 times as thick and what happens to the 900M signal? 5G bounces off a building like a mirror while 900M bends around? Scale the building up and see how 900M handles it. Similarly with the curvature of the earth and the "ground resistance" attenuation and scattering of vegetation and other surface structure.
But in the real world you have the same sized trees, buildings, and geometries, not sizes in proportion to each wavelength. So there are differences in the propagation, not just the fraction of the "celestial sphere" intercepted by the antenna structure of the far end of the link, to affect the link's behavior.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
Ethernet over AC gets blocked by the pole transformer, but I would be happy if it got to my detached pole barn-garage/woodworking shop, I suspect that would be my use for the HaLo WiFi. The Router we have now just will not reach that far.
Apocalypse Cancelled, Sorry, No Ticket Refunds