• By (Deleted User)

    Some juicy info from this announcement...

    [list=1][*]Wi-Fi in the 60 GHz frequency band[/*]
    [*]faster speeds than with existing Wi-Fi, into the 1 Gbit/sec., or faster, realm[/*]
    [*]multi-gigabit networking within the 60 GHz band[/*]
    [*]the Wi-Fi Alliance wants coming 60 GHz-capable devices be backwards compatible with existing Wi-Fi specifications[/*]
    [*]WiGig announced a specification in December, which it said at the time would result in data transfer rates between devices of more than 10 times faster than today's wireless LANs, or up to 7 Gbit/sec., about 10 times the 802.11n rate.[/*]
    [*]ABI Research forecasts that various manufacturers will build 2 million 60 GHz chipsets by 2015
    Wi-Fi is already available on nearly 1 billion Wi-Fi devices globally, and the group estimates that 10% of all people in the world use Wi-Fi. Wi-Fi is growing so fast that 800 million more devices will be shipped with Wi-Fi in 2010[/*]
    [*]Initially, WiGig is expected to have a significantly shorter range than Wi-Fi, he added. Wi-Gig would reach across a living room, while Wi-Fi reaches across a football field or more[/*].[/list]

    Talk amongst yourselves....

  • Great news. So we are heading for 802.11n/802.11ac for long range and 802.11ad and WiGig for short range high speed? That is going to make for some interesting deployments.

  • I'll stick with WUSB for now.

    60 GHz lab gear - analyzers, RF Enclosures, etc is going to be expen$ive.

  • One of the interesting things will be when we take a look at the graphs showing atmospheric attenuation versus frequency. O2 has a resonance peak right at 60 Gigs. Roughly 10 dB per click [ fairly steep roll ?off on each side however ].

    Manufacturing will be a whole new ball game. Producing components at 60 Gigs is a world removed from 2.4 and 5. Tolerances will have to be ultra-tight. Mega-tiny connectors. Excellent RF engineering will be needed [ along with expensive tooling ] to get the oscillators, mixers, antennas, couplers etc operating correctly.


  • Ok I may be missing something but higher frequency poorer propogation. 60GHz will not travel very far unless you push out alot of power, or am I oversimplifying this.

  • Pete

    Yes you are right. The whole picture becomes quite complex when we take in all the factors involved. When 802.11 came on the scene, there were already other users making use of the unlicensed spectrum. Literally Industrial users, Scientific users and Medical users. However, there were all sorts of other folks involved from the military to universities etc. Power limits were fairly strict in order to allow all users to try and co-exist as best they could. The expense of manufacturing 2.4 GHz and 5 GHz kit is ?not too bad?. This was one of the reasons Wi-Fi caught on.

    Up in the 60 GHz region, not too many folks have camped there. There are a few ?applications ? floating about, but no piles of radio users all over the place. Power regulations will likely be different from what we have now in our frequency bands.

    The gain of a parabolic antenna [ for example ] is given by 4 pi x antenna effective area divided by lamda [ squared ], where lambda is the wavelength of the signal. Up at 60 Ghz, an Xm antenna would have a much larger gain than an Xm antenna at 2.4 Gigs. On the other side of the coin, you can make a Y dBi antenna much smaller at 60 GHz than at 2.4 GHz.

    Most of the 60 Ghz stuff will probably be for indoor applications [ HDTV video streaming etc ]. 802.11k [ or a variant thereof will likely make an appearance ] in order to get feedback about link performance etc.

    For many years, universities and research institutions have conducted propagation tests on a whole slew of frequencies going up to and beyond 60 Gigs.

    802.11n is an important test bed for the development of .11ad.


  • Cool as long as its not screwing with the laws of physics as I understand them.

    I will one day understand all of that post?

    I may even print some of your posts out and put them in my office, save me decorating, its a home office so its a tip. Last room to get decorated etc but I digress.

    You sound like a freind of mine who was in the signals regiment, he was always in trouble for curring farmaers elctrified fences to length to make antennas? Clever guy, well he can make antennas, I think he callled them ground plane antennas.

    However that will be a later part of my knowledge gaps.

  • Hmm, Dave I'm interested in hearing more about what kind of testing at 60GHz people have been doing. Is it that they can push the power envelope up because they know it will only go a short range? I can imagine this tech being used to feed video to every room in the house, but is even that too far?

  • I read a very short piece that stated the core for the leap in data rates will be SDMA, just another acronym at present to me but another technology I will have to master.

    Not sure that helps

  • The key to getting long range [ just like with 802.11 the original at 1.0 Mbit/s ] is to drop the data rate. It depends on what you want to do. Range ? Rate ? Bit of both .Power is a very important factor. Free space attenuation loss increases by 6dB per doubling of distance. Attenuation due to the frequency component when comparing one frequency [ say 60 GHz ] to another say [ 2.4 GHz ] varies according to the ratio of the squares of the frequencies. At 60 Gigs, O2 absorption will give us a ballpark figure of say 10 dB per click. But !! because of the antenna gain equation, you can get some very nice gain figures for ?reasonable sized parabolics?. 60 Ghz is used for inter-satellite link experiments , where data is transferred directly from spacecraft to spacecraft.

    Here?s an example of some ?stuff? that?s being done:

    There are loads more out there. You can google ?EHF propagation? for example.

    At present you?ll often hear ?Oh, 2.4 GHz is so crowded and there?s not much on 5 GHZ [ obviously very generalized, but in some places true for various reasons ]?.

    However, Wi-Fi is growing exponentially [ It should be remebered that Wi-Fi was doing great until the horrors of WEP were exposed. A lot of damage control [ technically and PR wise ] had to be done to regain confidence and help allay the expression ?Oh we?re not investing in Wi-Fi too much?.haven?t you heard?.it?s insecure? There are still plenty of folks out there who still think that this is still the case. Won?t include legacy kit that can?t be upgraded etc ]. 5 Ghz is filling up fast in many places even with UNII 2e etc.

    I liken it to hard drives. Remember when you had your little drive with a few hundred Megs and said ?Wow, I?ll never fill that up !!???

    People seem to ?find? things to fill bandwidth up. Videoconferencing, HDTV streaming, gaming, full motion security video etc etc etc. New ?apps? for Wi-Fi are coming out all the time.

    Frequency bands can and do change, but take a look at the following chart down around the 60 GHz area.

    Look at the bandwidth. As our good friend Borat would say ?Very nice !!?. With that bandwidth and new encoding techniques/things learned from .11n, I have no doubt whatsoever that Gigabit Wireless in the home etc will become a reality. Office systems could come into play as well. One thing I have learned in wireless is that whatever seems pie in the sky today, will be pie on your plate some time down the future. There will be pitfalls and stumblings and salesmen making outrageous claims, but if I were a betting person, I would say it?s a pretty sure thing that we?ll get our Gigabit Wireless.

    I remember working on a 128 kbit/s link many moons ago and thinking ?that?s fast !!?. Then I started working on E-1?s [ 2.048 Mbit/s ] and said ?that?s fast !!?, then on 120 Mbit/s TDMA and said ?that?s fast !!? etc etc .

    If you were to ask someone ?In terms of theory, what is the single most complex ?item? in an AP or WLC ??. Most folks would probably say the microprocessor or the DSP or the firmware code. As clever as these all are, the plain old antenna ?s theory is infinitely more complex. Double integrals for a start [ in the calculus sense ] in parabolics. How the electromagnetic wave behaves in the near-field alone is extremely complex . Most of the books [ the real ones ] on antenna design are as thick as your arm. Do you need to know any of it for practical work ? Almost never.


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