On the assessment of cochannel interference in wireless systems by the saddle point approximation

Many papers have considered the problem of how to calculate the probability of outage due to cochannel interference in cellular radio systems. A gener al approach based on the characteristic function method has been recently p resented in [1, 2] and in [3] in the cases of Nakagami fading and Rice fadi ng, respectively. However, closed-form results are available only in a few cases, while numerical integration and/or evaluation of special functions i s the solution for other cases. In this paper we follow a similar approach as in the above works, but we evaluate integrals by using the saddle point approximation method which has proven itself to be fast and accurate. Some comparisons between our results and the results published in the above refe rences are reported.