LAUSR

In the conventional beamforming-based transmitting scheme for a multiple-input single-output (MISO) system, many transmitting antennas are usually required. In this paper, a direction of arrival (DOA) based spatial focusing scheme for a 2 × 1 MISO system is proposed. This 2 × 1 MISO system, can be employed for local or indoor communications, requires only one single and two antennas at the mobile station and the base station respectively. In the system, orthogonal-frequency-division-multiplexing (OFDM) is employed for the uplink and ultra wide band pulse is employed for the downlink. Firstly, based on the characteristics of OFDM, a multi-carriers DOA estimation algorithm is proposed to estimate the DOAs of multiple OFDM signals by using only two antennas, even the signals are coherent. Secondly, by using a fusion approach which fuses the estimated DOAs and an existing fixed focusing method, the spatial information focusing for mobile multi-users can be achieved. Numerical examples are provided to demonstrate the effectiveness of the proposed approach.