Hybrid macro/microdiversity techniques in the reverse-link wireless communication networks

We investigate microdiversity-augmented macrodiversity techniques in wireless communication networks. The setup consists of K widely separated access ports each carrying N antennas. The conventional selection macrodiversity (Scheme I) and two proposed methods (Scheme II and Scheme III) for port selection are investigated and their performance are compared. Scheme II utilizes the advancement in distributed antennas and radio-on-fiber technologies whereas Scheme III utilizes these technologies in a way similar to the soft handover of CDMA systems. After the port selection, the microdiversity uses n strongest signals (n les N) of the selected port for diversity combining if practical constraints preclude the use of all N signals. Analytical performance expressions for the probability of error and outage probability for Scheme I are developed. Simulations are used to investigate Scheme II and Scheme III and it is observed that these latter schemes exhibit performance superiority over the conventional macrodiversity selection method. The power savings obtained using the proposed architecture and new selection schemes could be used either for coverage extension or to increase capacity in wireless networks