Trellis-Coded DS-CDMA Multiuser Communications

• Main Authors: Huang Lee, 李晃
• Other Authors: 陳光禎
• Format: Others
• Language: zh-TW
• Published: 2002
• Online Access: http://ndltd.ncl.edu.tw/handle/35731175355131619960

碩士 === 國立臺灣大學 === 電信工程學研究所 === 90 === We investigate the trellis coding structure applied in the direct-sequence code-division multiple-access (DS-CDMA) multiuser communications. A multi-sequence model is proposed. By using this model, we can explain how to incorporate coding with DS-CDMA systems, and dene the measure to com-pare dierent transmitters. We also introduce the optimum detector in max-imum likelihood sense and derive the upper bound on the free distance and lower bound on the near-far resistance for coded DS-CDMA system. Because the tremendous complexity of the computation power, we also introduce three low-complexity sub-optimum detectors. The numerical results indicate that 3 - 4 dB coding gain can be achieved by using simple encoder with multiuser detection.