[Nottingham] wireless 54Mbps for desktop PC

.waffle nottingham at mailman.lug.org.uk
Thu Jul 17 18:40:01 2003


Lee wrote:
| hmm, so how do you know it's PBCC that's being 'better' than OFDM????

Independant test have shown that PBCC has a lower failure rate over normal
environments whereas OFDM has a lower failure rate where there are no
obstacles ie/ walls in the way, and in an ideal environment.

| What's the output power of your and the receive sensitivity of your
| card??? most of OFDM is rated at 15dbm and -65db@54meg....
| you know, the faster the bit rate the lower the receive sensitivity??

I have no idea, sorry. The technical info just says Antenna Gain of 2dBi. No
mention of any sensitivities. TI have not released this purposely I think so
they could get 802.11g accreditation (aka so no-one steals the idea). Now
that's all blown over - they're just sore losers.

| do'nt be fooled into thinking the raw encoding method is any better than
| ofdm, I mean, okay it works through to walls, but what about a lot of
| multipath, how does it handle it......what we need is an ofdm vs pbcc
| shootout...

OFDM v PBCC "shootout" has been done in the past. PBCC won in "noisy"
environments, whereas OFDM was better in "quiet" (ie/ point to point)
scenarios where reflection is minimised. I'll try and get you a copy of the
report, but rest assured, PBCC works better in your average environment.

| either way, TI or Broadcom arnt giving us linux drivers, and the ACX100
| chipset drivers are pretty useless, try using anything bar channel 1!!!!

I have... I use Channel 6, and run an acx100 linux driver. It works
flawlessly. Better than WinXP in my experience, as WinXP tries to be clever
and search for other networks, whereas Linux can be locked onto one config.

| so, PBCC / OFDM whatever....just give me some linux drivers, with good
| signal quality / link stat's reporting..and I will be a happy droid.

Indeed