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Just as you thought you could breath a little easier in this fast paced wireless world that we live in there's a new kid on the block, well a new standard in the making and it will be here sooner than you think. Yes another new standard.

I can recall when I got my first 802.11g access points and panic set in about compatibility with the 802.11b we already had installed. I needn't have worried but I was still a novice. I didn't even know at that time about 802.11 or 802.11a.

A little history, the 802.11 standard was minted in 1997 provisioning 1 Mbps and 2 Mbps in the 2.4 GHz spectrum, I know it seems along time ago but it had a decent uptake in manufacturing and warehousing. Only 2 years later 802.11b and 802.11a came along, that?s 1999. 802.11a provisioned up to 54 Mbps but was slow to capture the market due to generic client support. 802.11b on the other hand took off and everything was built with 802.11b that could be. We all know the advantages of 802.11a over 802.11b, higher throughput, less congestion etc but client support meant 802.11b stormed the market. Then 802.11g came along in 2003 and there was even less need to move to 802.11a as 802.11g in the 2.4 GHz spectrum was as fast as 802.11a and more accessible.

We waited an awfully long time for 802.11n with many many false dawns, it finally became a standard on September 11th 2009, about tea time if I recall, well that?s when I got the news. Just for the record 802.3af became a standard on the same day but was eclipsed by the hoopla surrounding 802.11n.

802.11n was so different its a whole new set of rules for us wireless engineers to learn, channel bonding, MIMO, frame aggregation, block acknowledgements etc etc and promises up to 600 Mbps.

Well now we have 802.11ac, there is little out in the real world that goes into any great depth about this proposed new standard, however, it is being touted that it will be a standard in December 2012, that?s not far away at all.

All is not lost however as it seems that it will largely an evolution of 802.11n or at least some of the technologies. The basis for the enhanced speeds, over 1 Gbps, will be further channel bonding with talk of 80 MHz and even 160 MHz wide channels. Now it would appear that this would only be feasible in the 5.0 GHz spectrum as there are not enough reusable channels in the 2.4 GHz spectrum. Even with all the available channels in the 5.0 GHz spectrum it is unlikely that there would be enough non overlapping air space to deploy an enterprise cell based implementation as we do today. Slight improvements in modulation techniques will also push up the speed.

A major breakthrough could come in the form of MU-MIMO (multiple user MIMO) where simultaneous streams are given to users on the same channel.

Product may hit markets as early as next year however I get the general feeling that it will have more specific applications than 802.11n due to the channel bonding and would be ideal for streaming HD video or high speed PtP or PtmP implementations.

802.11ac also has a big sister, 802.11ad, similar technologies but working up to 60GHz where I believe there is a lot of spectrum available. This however would be severely limited in its signal propagation as we all know the higher the frequency the poorer the range so 60GHz is going to be working between two devices in relatively close proximity.

One thing is for sure, the wireless market place is technologically innovative and our jobs and skills will only be more valuable as we ride the crest of the wave.

I think you meant 802.3at not af right? I could see ac/ad being useful for short range things like streaming HD between rooms in the home. I read that part of the reason .n took so long was there was some pretty major fights between different camps in the early days. Hopefully we are all past that now and the new standards won't take so long. All in all its a good time to be a wireless engineer, what with relatively few people really knowing it well so the value on the skillset is high.

Yep Chris 802.3at, at least someone read it!!!

Many thanks

Oh I read a lot of stuff on here Pete, I only post when I think I've got something interesting to say though. Good post!

Is there any significant gain in the distance range with 802.11ac that vendors are working to exploit?

Being at such a high frequency, it won't be a gain in range. However, it might be the Reduction of range that will be exploited.

Windows, walls, waterfalls, ... most everything is going to limit the maximum range.

It will be easier to get more stations in a smaller area without worrying about interference. Imagine your wireless streaming video not interferring with your roomates video next door - and higher video quality to boot.

My understanding is that it will only have an effective range of a few metres, saying effective range though I mean the range where you get significantly higher throughput.

So video etc is where its probably targeted and I also think domestic rather than enterprise as you would need a lot to cover an office environment.

Recall that as frequecy goes up it has less range ie does not propogate as far so there will be no range improvements at the power levels we deal with

My understanding is that it will only have an effective range of a few metres, saying effective range though I mean the range where you get significantly higher throughput.

So video etc is where its probably targeted and I also think domestic rather than enterprise as you would need a lot to cover an office environment.

Recall that as frequecy goes up it has less range ie does not propogate as far so there will be no range improvements at the power levels we deal with