Slow FH/16QAM mobile communication system with an interference immunity decoding method

This paper proposes a slow frequency hopping (FH) system using 16-ary quadrature amplitude modulation (QAM) for land mobile communications. The system uses pilot-symbol-assisted QAM for high spectral efficiency and uses orthogonal slow FH and forward error correction (FEC) with symbol interleaving for high-quality transmission over frequency-selective fading channels. The proposed system also uses an interference-detection-assisted decoding scheme to further enhance immunity from co-channel interference. Computer simulation shows that the proposed system can provide high-quality transmission over channels with frequency-selective fading and co-channel interference. It also shows that the interference-detection-assisted decoding scheme is especially effective for reducing the bit error rate (BER) when the interference level for each frequency of FH is dispersed