A decision-aided adaptive equalizer with simplified implementation

A design for adaptive equalizers is proposed, in which the computational complexity involved is significantly less than that of conventional adaptive equalizers because almost all the multiplication operations involved in the latter are replaced by addition operations in the former. The key point is that by taking intermediate decisions from the received signal and using these decisions with finite possible values rather than the received signal samples to calculate the equalized signal and to adjust the equalizer tap coefficients, multiplication can effectively be replaced by addition. The discussion is based BPSK (bipolar phase-shift-keyed) modulation but can be easily extended to other modulation schemes. For example, there is only one thing to be modified for QPSK-complex values instead of real quantities in signal and tap coefficients must be used.<>