Adaptive beamforming for TDMA signals

This paper addresses the design of adaptive beamforming algorithms used to improve the reception of time division multiple access (TDMA) signals in an environment rich in multipath and co-channel interference. A formulation of the problem is presented with an emphasis on "real-world" issues such as frame synchronization and partial slot overlap due to co-channel interferers. Three beamformer-demodulator structures are examined along with algorithms for adaptively optimizing their performance. Simulation results are provided to show that the beamformer-demodulator structures can significantly improve the bit error rate as a function of the SINR compared to a single antenna system. The computational complexity of the various structures is compared and shown to be reasonable for implementation on a set of TMS320C40 digital signal processors.