Antenna beam pattern modulation for MIMO channels

In this paper, the antenna beam pattern modulation (ABPM) is presented as a transmission scheme which uses antenna patterns in addition to the conventional amplitude/phase modulation (APM) symbols to convey information and increase spectral efficiency. The transmitted bits per symbol period are divided into two blocks: the first block contains the antenna beam patterns and the second APM symbols. Then, the second block is mapped to an APM symbol, which is transmitted by the antenna pattern selected by the first block. The beam pattern and the transmitted symbol are detected using the maximum likelihood (ML) by the receiver, in order to de-map the block of information bits. The bit error rate (BER) performance of the proposed ABPM is evaluated over independent and identically distributed (iid) Rayleigh fading channel. The simulation results show that with appropriately designed beam patterns, the transmission scheme can provide a better performance and enhanced throughput when compared to conventional spatial modulation (SM) and APM.