Signal Space Diversity in Single and Multiuser Scenarios Employing Sphere Decoder Detector

The matrix structure of the received signals of a system employing signal space diversity and antenna array is obtained for both single and multiuser scenarios. With this structure, we are able to implement a sphere decoder detector at the receiver. Also, as a complement of the approach of Boutros and Viterbo, an exact closed-form expression to calculate the pairwise-error-probability between two symbol vectors for the single user scenario is obtained. Then, a highly accurate bit error rate upper bound is derived for this scenario. Finally, the asymptotic analysis of this upper bound expression is performed.