Subband adaptive array for STBC W-CDMA system

In this paper, presents interference suppression using a Space Time Block Coding-Subband Adaptive Array (STBC-SBAA) for uplink W-CDMA system over frequency selective fading channel is presented. The proposed scheme utilizes W-CDMA system with STBC and a receive array antenna with SBAA processing at the receiver. The received signal is converted into the frequency domain before de spreading and adaptive processing is performed for each subband. A novel SBAA construction is introduced to process W-CDMA signals based on STBC. To improve the performance of the proposed scheme, the evaluation is performed over STBC-SBAA using spreading codes. Simulation results demonstrate an improved performance of the proposed system for single and multiuser environments compared to competing related techniques.

I. INTRODUCTION

There is an ever-increasing need for next generation wireless systems to provide higher data transmission rates to meet the emerging demand for new multimedia applications[1]. This presents a major challenge for wireless technology, namely to increase system capacity and quality within the limited available frequency spectrum [2]. It is well known that W-CDMA system is a promising means to meet the high data rate demands of next generation wireless systems. To achieve high-speed data transmission, high-quality communication or high-capacity communication, countermeasures should be employed to combat these impairments. The use of multiple antennas at the physical layer (multiple input multiple output (MIMO)) counters multipath fading channel and provide spatial diversity [3]. They showed that the capacity of a multiple-antenna system grows at least linearly with the number of transmit antennas, provided that the number of receive antennas is greater than or equal to the number of transmit antennas [3].