標題: Error statistics of closed-loop power control in multirate DS-CDMA cellular systems
作者: Wang, LC
Chang, CW
電信工程研究所
Institute of Communications Engineering
關鍵字: close-loop power control;Walsh code;scrambling code;power control error;power control false command
公開日期: 2002
摘要: In this paper, we investigate the error statistics of the close-loop power control scheme with variable spreading factors for the multi-rate services in the third generation wideband CDMA (WCDMA) system. We demonstrate that the long scrambling pseudo-noise code, besides its well known feature in differentiating users and base stations, can improve power control false command over a frequency-selective fading channel as well. Our computer simulation results indicate that the SIR measurement error can be reduced by 3 dB in a typical case, and the power control false command can be reduced from 27 % to 10 % in comparison to using pure short Walsh codes. It will be shown that the close-loop power control error is a composite function of spreading factor, target E-b / N-o and Doppler frequency. The statistics of closed loop power control false command can be easily characterized by a Bernoulli distribution with a parameter provided by our results.
URI: http://hdl.handle.net/11536/18890
ISBN: 0-7803-7376-6
ISSN: 1525-3511
期刊: WCNC 2002: IEEE WIRELESS COMMUNICATIONS AND NETWORKING CONFERENCE RECORD, VOLS 1 & 2
起始頁: 712
結束頁: 716
顯示於類別:會議論文