| One of the primary concerns in wireless data communication systems is bandwidth efficiency. Recently, multilevel quadrature amplitude modulation has acquired significant attention as it offers this benefit, however, as M increases, the accuracy requirements to achieve optimum performance increase as well.;The study herein lies in the performance analysis of an adaptive receiver taught in a patent filed in the United States Patent and Trademark Office (USPTO) by Dr. Rajendra Kumar and the author of this thesis. The analysis is exerted for 16-QAM and 4-QAM modulated signals. The robust receiver architecture encompasses adaptive techniques proposed earlier for GPS systems as well as a carrier recovery loop with a novel phase detector able to acquire the carrier of the incoming signal even in the presence of severe frequency non-selective Rayleigh fading. The adaptive techniques provide an accurate filtered estimate of the instantaneous channel fading envelope, whereas the phase detector provides an accurate carrier phase estimate to the Kalman filter or the optimum fixed lag smoother, which subsequently provides the predicted phase or the smoothed phase respectively to the reference carrier oscillator such that the carrier phase estimation error remains small even in the presence of channel phase noise.;This document discloses technical information from a US patent pending. |
