How to get a RF receiver sensitivity from SNR data?

Hi,
I read an article on WiMax RF receiver sensitivity. It first gave SNR (2.9 dB) for QPSK signal. Receiver NF is 5.5 dB, implementation loss 1 dB. Then, it said that for a 10-MHz desired channel, the QPSK sensitivity is ?94.6 dBm.
Here is the link: http://www.eetimes.com/document.asp?doc_id=1272474

I would like to know how to get '-94.6 dBm. Any one can help me?

Thanks,



I just get my result for 10 MHz bandwidth. It is -94.43 dBm.

For the result on 3.5 MHz width, 5.5 dB NF, I get -102.89 dBm. I don't know why the author had -103.1 dBm. Which one is correct?
Thanks,

I would not bother by tenths of a dB. Sensitivity is a vague term. More accurately one handles noise power in dBm or Watts, and signal power in dBm or Watts.
Depending on a selected modulation type, S/N ratio affects some modes more than others.
For modulated signals it is more common to use Eb/Nr ratio or other which includes interference with thermal noise. Spectrum of a digitally modulated signal also differs making the signal bandwdth slightly different from that for AM or FM.