A CSI reduction method of block cooperative decoding system in OFDM wireless communication scheme

Cooperative decoding is powerful technique for establishing good quality TV broadcasting. In cooperative decoding, some TV receivers, nodes, are cooperated, each other. These share the received information signal and thus obtain good quality information signal. Incremental-Maximum Ratio Combining (I-MRC) is one of the cooperative decoding methods. In I-MRC, the best condition's node and second one are selected among the cooperated nodes. The best node requests to send the received signal from the second one to best one. The best nodes combines the sent single with the own received signal and thus the good quality information signal can be obtained. After that, the best node broadcast the obtained information signal to all the cooperated nodes. Since TV's information signal should be broad band, it suffers from multipath fading. Even if the received signal of the second node is larger average SNR, there are the decayed frequency spectra in the information signal. In the proposed decoding, wireless communication scheme is orthogonal frequency division multiplexing (OFDM) and the best nodes request to send frequency subcarriers from each node to best nodes. As a result, the best nodes can collect only the good condition's subcarriers. In the proposed technique, the sharing of the significantly attenuated frequency spectrum components is avoided. In addition, for reducing the amount of exchanging pre-information (channel state information: CSI), the self selection of resource block is proposed. We show the proposed cooperative decoding achieves good error rate performance by computer simulation.