Signal Diversity Combining for Improved Satellite Communications

Period of Performance: 04/15/2002 - 01/15/2003


Phase 1 SBIR

Recipient Firm

Mobile Satellite Services Corp.
18221 Flower Hill Way #A
Gaithersburg, MD 20879
Principal Investigator


Signal diversity combining is a method whereby a signal is transmitted over multiple satellites to increase the transmitted power. At the receiver, the signals are combined coherently to improve signal to noise ratio. MSS is proposing to apply a novel concept of rapid prototyping to simulate various spatial signal diversity combining algorithms in real-time. This approach will yield a much higher level of accuracy than computer-based simulations, due to the shear number of samples processed. The simulation model representativity will also be increased by the use of real modulators and demodulators, instead of often over-simplified mathematical models. Unlike maximal ratio combiners which rely almost exclusively on signal-to-noise ratios to compute the combiner weights, MSS is proposing to use additional signal quality sensors, such as unique word lock status, bit error rate, interference detection and receiver lock status. The expected product of this Phase I activity is a combiner hardware module which can be commercialized through MSS's comblock family of rapid prototyping modules.