A Channel Estimation and Data Transmission Scheme Utilizing Superposition Modulation for Cooperative Communication

In cooperative communication, the channel estimation is important because the channel influences the transmission signal. General channel estimation schemes are conducted before the information signal. But, the channel is time-varying, dynamic and unpredictable. To cope with a constantly changing channel, a new scheme is proposed. In the proposed scheme, the new transmission signal utilizing superposition modulation is used. The proposed transmission signal is superimposed to the pilot signal for the channel estimation and the information signal for the transmission of information signal. As a result, the proposed scheme has similar to the bit error rate performance and throughput compared to when the channel estimation perfectly is performed. By using the proposed transmission signal in cooperative communication, the proposed scheme can estimate the channel through information signal and transmit the information signal at the same time. Therefore, the proposed scheme can estimate the channel that passes information signal and transmit information signal at the same time.