Selection of diversity and modulation parameters for Nakagami fading channels to jointly satisfy outage and bit error requirements

Outage is an event of instantaneous signal-to-noise ratio or bit error rate falling in an unacceptable operational regime. Outage performance analysis is traditionally carried out for different channel behavior and transmission techniques, leaving the identification of unacceptable operational regime to user specified performance requirements. An alternative approach is taken in this work and an acceptable combination of system parameters are identified such that the user specified quality of service (QoS) constraints are satisfied. The QoS constraints are specified jointly in terms of outage probability, outage duration and probability of occurrence of errors during the outage event. Analytical expressions are presented to compute the appropriate combination of diversity order, modulation scheme and average signal-to-noise ratio required to meet the performance constraint. The analysis assumes identically, independently distributed Nakagami interferers using maximal ratio diversity combining (MRC).