الفهرس | Only 14 pages are availabe for public view |
Abstract Transmission is considered for a synchronous direct-sequence code- division multiple –access (DS-CDMA) system via nonlinear satellite channels, with BPSK and QPSK modulation schemes which lend to coherent demodulation. Multiuser detection strategies are derived and analyzed for several signal detection problems arising in code-division multiple-access channels. The channel model takes into consideration the TWTA satellite nonlinearity which affects the signal amplitude and phase by AM-AM and AM-PM distortion, in addition to the background noise of the channel at the receiver, and multiple access interference for different number of users shared on the same channel. Since the optimum detector requires high computational complexity that grows exponentially with the number of users, and the implementation of this detector will be very complex, so different types of suboptimum detectors are studied. |