Reduced complexity short-block data detection techniques for fading time-dispersive channels

The achievement of reliable digital communications over fading channels with severe time-dispersion is considered. Two short-block data detection techniques based on linear and nonlinear decision-directed estimation principles are investigated. Short alternating blocks of data and training symbols are used. The training blocks are useful for both channel tracking and data block detection. In contrast to the recursive symbol-by-symbol equalization approaches usually used, each data block is detected as a unit. Previous restrictions imposed on short-block detection schemes have been removed, resulting in reduced complexity algorithms and higher throughput efficiency. Performance is presented for QPSK (quadrature phase shift keying) type signaling using a Rayleigh fading channel model with severe time-dispersion