Error Probabilities for Partially Coherent Diversity Reception

The probability that an ideal coherent receiver errs in receiving a noisy -ary, orthogonal transmission through independent slow Rician fading channels is derived. The receiver to be analyzed coalesces coherent and noncoherent reception. A more easily implemented, linearized version of the same receiver is presented, and the performance of both are compared with a previouslyanalyzed noncoherent detector. For small random channel components, the linearized receiver performs almost identically with the optimum receiver. Neglecting the information contained in the random component shows up as an additional noise component in the output and there exists an irreducible error probability, even in the absence of the additive disturbance, which depends on the ratio of the energy received via the specular channel components to the mean squared value of the scatter components. Thus, the importance of using the information conveyed via the channel scatter components is clearly manifested.