Re: [STDS-802-16] WiMax coverage factors
Ramzi:
Many factors when comparing OFDM 802.11 to OFDM 802.16.
Note: I am not comparing OFDMA 802.16 to OFDM 802.11:
1) power (or EIRP) as you mentioned.
2) Frequency (802.11a at 5GHz can covers less than 802.16 at 3.5 or at
2.5GHz). And yes, 802.11g at 2.4 should be comparable (at the same EIRP
levels) to 802.16.
3) Antenna gain in a sectorized environment. 17dbi antenna gain is not
typically used in WiFi.
4) The attempted WiFi information rates are higher than 802.16 - a link
budget entry
5) Delay spread in outdoor environment are longer than indoor.
6) Receiver sensitivity not the same. (802.11 devices are dirt cheap)
7) Required SNR are not the same. Are we to assume same coding
techniques for both?
8) Thermal noise density (dbm/Hz), which is higher for 802.11 as the
WiFi BW is wider.
Cheers, Peretz Feder
On 11/20/2006 3:18 AM, Ramzi Tka wrote:
> Hi All,
> Since WiFi and WiMax could use a same Physical Modulation (OFDM) and
> same coding schema (BPSK, QPSK,QAM), could we say that the factor that
> make WiMax coverage much more greater that WiFi coverage is the Tx Power?
> Best Regards
> Ramzi Tka