Bluetooth and 802.11b

[Bob Edwards]

I operate both in close proximity with no noticable effects. However, a study 
was done in which a bluetooth and an 802.11b card were located in adjacent 
PCMCIA slots and apparently the throughput on both went to near zero (I don't 
have the reference here). I suspect that the different transmitters were 
flooding the others receivers.

Bluetooth is a Frequency Hopper, switching 1600 times/sec in 1MHz bands (79 in 
all). 802.11b is Direct Sequence and occupies a 22MHz chunk of bandwidth.

In theory the DS nature of 802.11b should make it to some extent immune from 
the effects of the 1MHz-wide bursts of noise from Bluetooth.

Also, Bluetooth has a range of about 5m, so won't even be seen by 802.11b 
devices operating more than that distance away (this is a simplification - it 
is likely that the 802.11b receivers are more sensitive than the average 
bluetooth receiver). However, bluetooth may well be affected to some extent by 
a nearby 802.11b transmitter which will be relatively powerful.

So, this is not a clear answer and depends upon many factors. Personally, I 
believe that Bluetooth is here to stay, and if not, then something else will 
step into its place. It is even an IEEE standard now (802.15).

Cheers,

Bob Edwards.

Dale Shaw wrote:
> What's the reality when it comes to Bluetooth interfering with 802.11b?
> 
> Scenario: single WLAN in a small apartment with a few 802.11b nodes and
> a couple of Bluetooth devices. Any _noticeable_ performance degradation?
> Is it worse if I've got a notebook with a wireless NIC and a Bluetooth
> transmitter?
> 
> Cheers,
> Dale