> So, Jim, are you saying that .b will have advantages outdoors that .a & .g don't 
>have? 

No, thats not what I said.  Here is what I will say: 

1) 802.11g and 802.11a will have advantages indoors compared to
   802.11b.  At a given data rate, OFDM will perform better than CCK
   in an environment with a lot of multipath, until the delay spread
   approaches the guard interval.

2) OFDM's performance (compared to CCK) outdoors will depend a lot on
   the physical environment.

3) I advise 'caution' if you're considering 'mixed mode' 802.11g
   deployments (simultaneously supporting 802.11g and 802.11b STAs),
   especially prior to full IEEE standardization.  It is rumored that
   some chipsets "fall back" to 802.11b for the entire BSS if but a
   single 802.11b STA associates.  (I haven't seen this myself.)

4) Rate adaption algorithms are one of the places that will make a big
   difference in how any given OFDM chipset performs.

5) OFDM does trade off receiver sensitivity (and complexity) for data
   rate.  (There is no free lunch.)  Moore's law will eventually
   eliminate the complexity issue, when the marginal cost of the extra
   silicon can't be measured.

Jim

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