An energy-minimization technique for time-domain design of preset digital equalizers using quadratic programming

A quadratic programming technique is presented for the design of a preset FIR digital filter to equalize the intersymbol interference (ISI) present in a baseband channel with known impulse response. An energy-minimization technique is used which minimizes the transmitted energy while holding a constraint on the ISI in the received waveform. Transversal and frequency-sampling equalizers designed by the technique and by a minimax technique are compared. The minimax design produces a channel output pulse which approximates a specified ISI-free pulse. The results show that the energy-minimization designs have less ISI distortion and require less transmitted energy than the minimax designs.