Eigenbeam- space division multiplexing for OFDM systems with optimum resource allocation

A promising solution for significant increase of bandwidth efficiency and system capacity is the exploitation of the spatial dimension, by using space division multiplexing. When the channel state information is known at the transmitter of multiple-input multiple-output systems, the optimum capacity is achieved by eigen mode channel division with water-pouring power control. In this paper, frequency domain eigenbeam-space division multiplexing is proposed for orthogonal frequency division multiplexing (OFDM) with a method to assign both bits and transmit power to each substream. This assignment is based on the criterion of minimizing the error rate. The symbol error rate (SER) performance of the proposed E-SDM-OFDM system is numerically analyzed and compared with the SDM-OFDM system. It is shown that the proposed E-SDM-OFDM scheme can significantly reduce the bit error rate compared to the conventional SDM-OFDM system.