Bit error rate in multipath wireless channels with several specular paths

A recursive and computationally efficient new formula for bit error rate (BER) in multipath channels with several specular components is derived. Using Jensen´s inequality, it is shown that one specular component, Rice fading, provides the lowest possible BER. Using Lagrange multipliers to solve a constrained optimisation problem, it is further shown that, for two specular components, BER is maximum when the two components have equal strengths. BERs for three and four specular paths are studied and compared numerically. The results show the impact of the number of specular paths on BER, as well as the smallest and largest BERs.