QPSK data rate vs bandwidth

Hello all,

Please could someone confirm this.

In a satellite link design i have specified a bandwidth of 80MHz. My modulation scheme is QPSK. I have then stated that since QPSK is capable of transmitting 2 bits per hz (?), the link can achieve a data rate of 120Mbps.

Is this fundamentally correct ? Or am i missing something obvious here

Also, Can anyone shed some light on modulation index ? And how it would be related to the application i've mentioned ?

Thanks,

J



That should have been 160Mbps*** Sorry! I failed to times 80 by 2 :(

J