A new direction finding scheme for DS/CDMA systems with array antenna

This paper proposes a new scheme for finding direction of arrival (DOA) and channel impulse response of each user's signal for third generation direct sequence code division multiple access (DS/CDMA) systems. For the third generation DS/CDMA systems, the pilot signal is simultaneously transmitted with the data signal through the pilot channel in the uplink. The proposed DOA and channel impulse response estimation scheme makes use of information contained in both pilot and traffic channels. We initially estimate the DOA and channel impulse response using a pilot signal. We then estimate the DOA and channel impulse response using the traffic data bits, and optimally combine those estimation results on the DOA and channel impulse response of pilot and traffic channels. An analysis of the accuracy of the direction finding is given and simulation results show that the proposed scheme improves the accuracy of the DOA and channel impulse response estimation significantly.