The Research Of Wireless Channel Model In Telemeter System And Parameters Estimation Of Signal

The radio channel is a bottleneck restricting the development of wireless communication. Channel characteristics research, radio channel model and simulation are the base of the wireless communication theory analyses and systems designs. An analysis of the impact on signal from the radio channel, an estimation of signal parameters is the base of analysis the quality of the receive signal, modulation recognition and demodulation latter. Therefore, the estimation algorithms research of signal parameters is very important to realize digital telemetry signal reception.The thesis studies a radio model and parameters estimation algorithms in the telemetry systems. By the analysis of parameters distribution law of radio channel, the universal radio models is established which simulating different typical environment when different environmental parameters being chosen. The model is intuitionistic and simple. Based on the idea of software radio, the parameters estimated in the head of receiver in telemetry system. Therefore a blind algorithm to estimate parameters without any priori conditions is the base point of the thesis. A Doppler frequency offset estimation algorithm studied in the thesis based on I-Q cross product frequency discrimination. Through analysis of the factors affecting frequentcy offset, the algorithm is improved, and in the context of achieve in practice the choice of parameters is given. A signal-to-interference ratio estimation algorithm is based on eigenvalues decomposition and subspace division, and problems of algorithm are given, and the suggestions to improve the algorithm are given.Finally, the improved algorithm is applied in a telemetry radio channel simulation systems as well as a telemetry signal beforehead processing system. A telemetry radio channel simulation systems simulates signal transmission in real channel, and a telemetry signal beforehead processing system estimates telemetry signal parameters include bandwidth, power, signal-to-interference ratio, Doppler frequency offset, and it filters noise and rectifies frequency offset. The military project-- "telemetry signal characteristics simulation system" which sponsors the thesis has been accepted successfully, so the productions of this thesis have higher practicality values.