Subcarrier Block Power Control for Adaptive Downlink OFDM with Frequency Spreading and Equalization

In this paper, we propose the transmit power controlled adaptive downlink frequency symbol spreading OFDM (TPC-AMS/FSS-OFDM) system. In the TPC-AMS/FSS-OFDM, each serial to parallel (S/P) transformed signal is spread by orthogonal spreading codes and combined in the transmitter, so the detected signals obtain the same SINR for each frequency symbol spreading block in the receiver. In this case, we can assign the same modulation level and transmit power for each frequency symbol spreading block for next transmission. Thus, the proposed system not only increases throughput performance but also reduces the total transmit power, FBI and MLI.