Spatial Diversity Combining Using Blind Estimation Techniques

Abstract

This paper proposes a spatial diversity combining approach by which spatially diverse telemetry signals from multiple antennas are combined before they are demodulated. The combined signal is guaranteed to at least replicate and in many cases improve upon the performance of any single antenna. By taking advantage of blind channel estimation, the combined signal can be computed as a time varying weighted sum of digital I and Q samples from multiple antennas. Multiple antenna combining is enabled by improved computation capability, high speed network connectivity, and accurate clock synchronization. The algorithm will be demonstrated at the Reagan Test Site (RTS), whose modernization program encompasses multiple antenna sites with network capability and a state of the art software defined radio back end. This paper details the spatial diversity combining algorithm and discusses its merits and challenges. Index Terms - Telemetry, Reagan Test Site, blind estimation, multiple antenna combining, best source selection, spatial diversity combining.