Application of Antenna Diversity Combing Techniques to Mobile Communication Systems

• Main Authors: Jia-jun Hong, 洪嘉俊
• Other Authors: Ching-Tai Chiang
• Format: Others
• Language: zh-TW
• Published: 2005
• Online Access: http://ndltd.ncl.edu.tw/handle/69514152986780322874

碩士 === 義守大學 === 電機工程學系碩士班 === 93 === The telephony, data, image, Internet and video applications are essential to future wireless communication systems. A variety of service requirements as mentioned above will demand advanced antenna array structures instead of traditional monopole antenna. Thus, multi-antenna transmission and reception techniques are currently seen as the most promising methods for enhancing the capacity and data rate of the existing code division multiple access (CDMA) systems. In tradition, diversity technique is equipped multiple antennas at the receiver. However, due to the requirement of compact size as well as the low power consumption for mobile station, the received diversity is not suitable for downlink transmission. In order to take advantage of diversity technique, multiple antennas can be easily deployed at base station, that is transmit diversity scheme. In this thesis, the performance degradation in bit error rate (BER) due to phase-only feedback with quantization error is investigated in a closed-loop transmit diversity scheme with multiple transmit antennas toward one receive antenna over a flat Rayleigh fading channel. A compact closed-form expression for BER performance in terms of number of antennas, quantization bits, bit energy and mean-squared channel coefficients are derived. Analytical results deduce that phase information dominates performance of the closed-loop transmit beamforming. Moreover, the advantage of transmit diversity with phase-only feedback may be provided already for three quantization bits. The result is helpful to design the channel information feedback system with finite bit allowance. It is also the main contribution of this thesis.