Real-time smart antenna system incorporating FPGA-based fast DOA estimator

This paper describes a practical hardware implementation of uplink smart antenna system useful for macro-cellular base stations. This system incorporates a fast DOA (Direction of Arrival) estimator which is called UMP (Unitary MUSIC Processor) using dedicated circuit device of FPGA (Field Programmable Gate Array). This system steers the main-lobe for the user basically with Dolph-Chebyshev beam. In order to avoid undesirable interference reception by broad main-lobe, an optional null-steering processing cancels the interferers within the main-lobe coverage with notch beams which are pre-computed and stored in ROM (Read Only Memory). The beamforming weight is computed by simple convolution operation of the pre- computed Dolph-Cbebyshev beam and optional canceling beam, thus the computation load for weight generation is extremely small. This paper presents the estimation performance of the UMP through the hardware level fixed point simulation and measurements. And total performance evaluation of this system tinder AWGN and multi-path fading channel with small angle spread will be discussed.