A simplified downlink transmission and receiving scheme for IDMA

In this paper, we propose a downlink transmission and receiving scheme for interleave-division multiple access (IDMA) system based on time-division duplexing (TDD) mode and time-reversal (TR) technique. The proposed scheme uses the time-reversed version of the channel impulse responses (CIR) obtained from the uplink to pre-process the transmitted signal at base station. By exploiting the weak correlations of fading channels for different user ends (UE), it is help to alleviate the multi-user interference (MUI) and co-channel interference (CCI). Moreover, the application of the TR technique in a multiple input-single output (MISO) configuration can reduce the delay spread of the channel impulse response, and mitigate inter-symbol interference (ISI). The UE can be simplified by canceling the iteration operation. Thus the data detection of the proposed scheme is rather simple as compared with the traditional IDMA, the complexity and computational load of UE is decreased substantially, and the proposed scheme provides a great deal of privacy and security to mobile users.