The Erlang capacity evaluated for DS-CDMA systems was obtained assuming perfect constant received power control and a single rate for all users. An assignment failure was declared when the total...

The Erlang capacity evaluated for DS-CDMA systems was obtained assuming perfect constant received power control and a single rate for all users. An assignment failure was declared when the total interference I0 exceeded the background noise level N0 by an amount 1/η. Now consider a multi-rate DS-CDMA system where each mobile terminal has its individual data rate, denoted Ri, and power control that provides each mobile terminal with its required (Eb/I0) = ξi, when feasible. a) Determine an expression for the blocking probability in this case. b) Compare the obtained results with the single-rate case when Ri = R, ∀ i