[ot] microwave and wifi

[Vu Pham]

On Wed, 2006-09-13 at 22:03 +0800, Man-wai CHANG wrote:
> > No.  Just because two different signals use the same frequency doesn't 
> > mean that they are the same signals.  Signals have many components, 
> > including frequency & amplitude.
> 
> frequency? I think you meant phrase. Both microwave oven and wi-fi use
> the same 2.4GHz right?

They do not work exactly at 2.4 Ghz. When saying 2.4Ghz, it means the
devices use the ISM band 2.4Ghz which is actually from 2.4 Ghz to 2.4835
Ghz. This 2.4 Ghz ISM band is unlicensed band approved worldwide.

IIRC, for 802.11b, their frequencies are 2.412, 2.417 ( 14 channels
which are 5 Mhz apart... the first 11 ones are for US/CAN ) and most
microwaves use 2.450. And even when we say 802.11b channel 1 uses 2.412
Ghz, in fact, it uses the range from 2.401 to 2.423 with 2.412 being the
central frequency.

Vu