Most of the previous research on multistage interference cancellation receivers for Code Division Multiple Access (CDMA) systems has relied on the use of simulation techniques for performance evaluation. This thesis formulates a model for an adaptive multistage interference cancellation receiver within a CDMA system to be employed at the cellular radio base station. A closed form expression for the probability of bit error for this adaptive multistage interference cancellation receiver is derived, using a Gaussian approximation for Multiple Access Interference (MAI). The Bit Error Rate (BER) after any stage of interference cancellation can be computed from the signal to noise ratio, number of users and processing gain of the CDMA system. The BER expressions are extended to derive asymptotic limits on the performance of interference cancellation as the number of cancellation stages approaches infinity, demonstrating a fundamental limit on the performance improvement that can be expected from any multistage interference cancellation scheme. Furthermore, the analysis quantifies conditions under which interference cancellation may degrade performance. This thesis also extends a software implementation of the Multistage Rake receiver for a wide range of channel models including Gaussian noise, MAI, multipath propagation and near-far effects. Simulation results demonstrate the robustness of the Multistage Rake receiver to near-far effects and manifold capacity improvement compared to conventional demodulation techniques. / Master of Science

International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada / The Space and Missile Systems Center at Vandenberg AFB has integrated ID-1 high bit rate helical scan digital recorders into the ground based and mobile telemetry receiving and processing facilities. The systems are used for recording higher bit rates than those available with the current IRIG standard longitudinal wideband and double density instrumentation magnetic tape recorder/reproducers. In addition to the 400 Mbps digital recorders, the systems consist of high-speed multiplexer/ demultiplexers and multi-channel bit synchronizers for recording numerous telemetry data links and sources on a single recorder. This paper describes the system configurations and compares recording capabilities with those of the previous generation instrumentation magnetic tape recorder/reproducers.