An investigation of channel estimation and equalization techniques for moderately rapid fading HF-channels

Two basic schemes of channel estimation/prediction and decision-feedback equalization (DFE) for moderately rapid fading dispersive HF-channels are investigated. Simulation results show that non-adaptive adjustment of DFE coefficients by direct calculation from the estimated channel impulse response has the potential of being significantly more robust channel time variations than a DFE employing adaptive coefficient tracking. Receiver performance is now limited by the quality of the channel estimate rather than the equalizer´s adaptive algorithm. An optimized state-of-the-art adaptive estimator/predictor featuring individual adaptation of channel coefficients is shown to recover part of the potential performance gain