Data-Aided Channel Estimation for Time Diversity in Helicopter Satellite Communications

The periodic blockage of the transmission channel is the most important issue in helicopter satellite communications. Time diversity is a practical solution to overcome it, requiring channel estimation to implement maximal ratio combining (MRC). This paper proposes a channel estimation method for helicopter satellite communications employing time diversity. The proposed method estimates the channel gain by removing modulation from the received signal using the provisional demodulated data. The estimation is rapid and accurate. In addition, signal processing is simple. Computer simulation shows that the degradation of bit error rate performance of MRC due to channel estimation error is under 0.1 dB.