For future mobile communication systems, there exist demands for such various requirements as multimedia traffic and high rate data transmission. To accommodate these demands, we propose a truncated adaptive transmission scheme for the transmitter and a difference threshold test (DTT) for the receiver of the wireless communication systems.
Firstly, a truncated adaptive transmission scheme for the hybrid multicarrier CDMA/FDM system is considered in forward link. In the proposed scheme, a data substream is transmitted over the subchannels of which the channel gains are greater than a given threshold, based on the feedback information from the mobile station. We analyze the performance of the proposed system when orthogonal and random signature sequences are used in multiple cell environment.
Secondly, the DTT is considered as a reliability measure in noncoherent JVI-ary orthogonal frequency shift keying signaling with Reed-Solomon coding and diversity combining under the multi-channel environment. The DTT declares erasures when-ever the difference between the largest and second largest energy detector outputs does not exceed a given threshold. The performance of the DTT is compared with that of the ratio threshold test (RTT) for finite and infinite modulation size and diversity order.