Joint Design for LDPC Coded OFDM with Transmit Adaptive Antenna

A novel design is proposed for the OFDM system using structured LDPC codes with the transmit adaptive antennas (TxAA), which can achieve improved performance by adaptively using the feedback subcarrier frequency information at the transmit side. With the aid of the closed multiple antenna technique, much gain can be achieved in the coded OFDM system. Furthermore, irregular LDPC codes have the advantage of unequal error protection (UEP) for coded bits with different degree distributions. Thus mapping the coded bits with high degrees to the subcarriers with weak subchannel attenuation is proposed to fully utilize the feedback information not only in the design of the closed-loop OFDM transmission but also in the combination design of the coding scheme and OFDM modulation. The proposed scheme is proven to be effective by simulation results in the frequency selective channel scenario