Spectral efficiency of cellular mobile radio systems with different traffic loads

A lower bound on the Shannon capacity of the uplink channel of a narrowband cellular system is evaluated as a function of the reuse distance and the level of shadowing affecting the interfering signals, assuming perfect channel state information (CSI) at the receiver. The effect of the first two tiers of interferers is determined, and compared with a simplified evaluation that takes into account only the first tier. Spectral efficiency is evaluated for different traffic loads, to assess the usefulness of traffic control. The performance improvement that may be obtained by adopting the space diversity, to avoid deep fades in the received signal, is also evaluated. Our results show that traffic control may have a negative effect on the system performance.