Studies On The Adaptive Frequency Hopping System

Adaptive frequency-hopping system can perform adaptive channel estimation, and adjusts modulation, power control and frequency selection adaptively in accordance with channel conditions, thereby greatly enhances the system capabilities of anti-fading, anti-jamming and anti-intercepted. It is of decisive significance and this dissertation has done lots of researches on this subject.Paper first gives the characteristics of shortwave channel, the developing history of AFH system and the basic knowledge and the new development system as well as the development course of FH communications. Secondly, a detailed analysis of frequency hopping and adaptive frequency hopping system is based on technology, including basic principles, system model and so on. Then, the study of adaptive frequency-hopping channel estimation algorithm, right under the observation vector autocorrelation matrix eigenvalue decomposition algorithm for SNR seeking detailed study conducted in-depth discussion of the algorithm implementation details, such as the calculation of correlation matrix as well as the decomposition of the problem and for the classical algorithm issues that may exist in the corresponding improvement of methods, simulation analysis carried out to verify the correctness of the algorithm. Then study the adaptive frequency-hopping frequency control methods, including frequency of collection configuration, channel classification, classified information exchange, the frequency set update, such as adaptive frequency hopping patterns, the study focused on frequency-hopping pattern generation. In the analysis of the traditional method for forming the frequency hopping patterns Paper first proposed a new frequency-hopping pattern based on chaotic sequence generator implementation method. And the method used in the performance of chaotic frequency hopping sequences, Hanmming, balanced features and characteristics of frequency-hopping interval analysis to verified its can be used as adaptive frequency hopping system, hopping sequences.