Summary: | 碩士 === 國立臺灣大學 === 電信工程學研究所 === 89 === Major requirements for the 3rd generation (3G) cellular wireless communication systems include high transmission data rate and high capacity. Wideband code-division multiple access (W-CDMA) frequency duplex-division (FDD) mode is the most promising standard for the 3G cellular mobile communication system. Unfortunately, the performance of the conventional RAKE receiver for CDMA systems is interference-limited, therefore multiple access interference (MAI) is the major source of performance degradation. On the other hand, multiuser detection deals with the demodulation of mutually interfering signals of information, and can overcome the MAI problems effectively.
Parallel interference cancellation (PIC) detector is a multiuser detector that is very popular because it can be implemented easily and can alleviate MAI effectively. However, conventional MUD can only suppress intra-cell interference with a priori knowledge of the users’ spreading waveforms. We propose new structures that combine space-time processing and adaptive filtering algorithms with the conventional RAKE receiver and PIC schemes for improving performance in the presence of intra-cell and inter-cell interferences. From simulation results, we demonstrate that the receiver performance is significantly improved by employing the proposed structures in the presence of strong MAI.
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