802.16 WiMax Wireless Broadband on the Horizon

securitas writes "Products using the emerging IEEE 802.16 WiMax wireless broadband standard should be available early in 2005. WiMax's hundreds of megabits per second bandwidth looks promising to many vendors and service providers who met in San Jose at last week's Wireless Communications Association (WCA) International Technical Symposium & Business Expo. The point-to-multipoint 802.16d standard, with a 50-kilometre range, is expected to be complete by February, ratified in March and deployed in the first quarter of 2005." (Read on for more.)

"The IEEE 802.16e spec, which will support mobile applications, is expected to be complete by early 2005. Nextel, Sprint and BellSouth are all interested in the technology to deploy services like streaming video and TV, wireless phones, and high-speed Internet service in unserved, low-density areas near high-density ones. Mobile operators in developing countries like Brazil's NEOTEC group have already successfully tested an 802.16 wireless broadband deployment. Intel communications group executive VP and GM, Sean Maloney, is banking on it. From the article: 'We believe that WiMax can happen, and be widely deployed, and be a big deal in the next three years the same way Wi-Fi has been a big deal the last two years.' Mirrors at Network World Fusion, Techworld and PCWorld. What happens when techies start to build their own 802.16x WiMax VoIP systems?"

Comments

Re:This is promising.

[CaptainAlbert]

Usually, higher bandwith means higher frequency. Higher frequemcy means less range, since the waves is easilier interupted by obstacles, like trees. and so on. Someone care to explain this to me?

Without getting too technical - you're right, sort of. The article is rather muddled; it mentions the frequencies in question (2.5GHz region, which is microwave), and then has some confused sentence about "point-to-multipoint meaning no line-of-sight is necessary". Well, that's nonsense. Microwave propogation is almost exclusively line-of-sight. Without LOS, signal strength drops off dramatically.

However, if you use spread-spectrum techniques (which 802.16 does), you can overcome a lot of these problems. Basically, the characteristics of a wideband SS signal are such that multiple reflections (even weak ones) can be separately received and combined. This is a big gain over narrowband radio, where reflections cause inter-symbol interference which causes the signal to deteriorate.

Another factor that may be more significant - this standard seems mainly to be for delivering broadband to fixed installations (not mobile stations). Well that's an easier job by orders of magnitude: you only have to site the antennas correctly once, and you never have to worry about them moving around.

In conclusion: it's quite different from the radio technology we're most used to, and there's a little thing called progress to factor in too! :)

Hope that helps.

If you don't know what you're talking about

[Czernobog]

please refrain from posting.

Spectral efficiency measures the ability of a wireless system to deliver information within a given amount of radio spectrum and is directly related to system capacity. It determines the amount of radio spectrum required to provide a given service (e.g., 10 kbps voice service, 100 kbps data service) and the number of base stations required to deliver that service to end users. In the latter years of deployment, when subscriber penetration is high, it becomes one of the primary determinants of system economics.

Spectral Efficiency = Channel Throughput/Channel Bandwidth

Spectral efficiency is measured in units of bits/second/Hertz/cell (b/s/Hz/cell). It determines the total throughput each base station (cell or sector) can support in a network in a given amount of spectrum.

Copied from: http://www.arraycomm.com/pcct/spectral_efficiency. htm

There's a million places I could point you to. So to say that capacity and frequency are not related is simply wrong, if not ignorant. The same definition stands for all wireless communications schemes, regardless of whether they use cells or not. All operators, whether it's Telephony or Networking deploy their networks and offer services based on spectral efficiency and power needed to achieve that efficiency. Nothing else. Bit rates, Frequency and all the rest of it are just byproducts...

Five mod points, no sensible replies here

[puzzled]

I've got five moderator points this morning and there is exactly one post in here I'd mod up - the guy who suggested that people not post if they don't know anything, but he already has a +5.

There is a link in my sig to my journal and there you'll find a brief description of how 802.11 (wireless lan) and 802.16 (wireless access) differ.

50km == 30 miles. I've installed 2400MHz and 5800MHz links on the same 22 mile path and I've done a bunch of other 20 +/- 2 mile shots using 5800MHz.

At 22 miles with 19dB dishes on each end we saw analog modem speeds with 2400MHz (802.11b) equipment. Using 29dB 2' Andrew dishes and 100mw 5800MHz radios we saw a solid 5+ mbits on a radio that maxed out at 8 mbits.

I've planned a 40km 45 mbit shot for a project that didn't go through - I think we had a 4' dish on the remote tower and a 6' dish on the skyscraper end of the link.

Whatever band and modulation method they're using in these breathy 802.16 announcements the physics aren't going to be much different than what I describe above - long shots are point to point, cells are small (3km - 4km) if you want to go fast, and I mentally say "snake oil" when I hear the letters O-F-D-M. It works, but it ain't "all that", as they say.

So, mod me wise, or mod me troll, but know this: The slashdot collective has as much business talking about wireless networking as any room full of male gynecologists and cross dressers has talking about childbirth.