Research On Blind Receiver Technology Of Frequency Hopping Communication Signal

Frequency hopping communication has strong anti-interference ability, high spectrum efficiency and easy realization of CDMA, excellent multi access networking etc. In addition to obtain the widespread application in the military communication electronic warfare, such as the application in tactical frequency hopping radio equipment, the technology in the field of civil communication has also been rapid development, such as mobile communications, data communications, computer wireless data transmission. At present, non cooperative communication is one of the key research directions. In the complex and changeable application environment, the blind reception technology becomes a research hotspot in the field of frequency hopping communication, because it can not directly obtain the prior information of the communication signal.This thesis mainly studies the blind receiver technology of frequency hopping signals. On the basis of theory of frequency hopping communication, design the blind receiver receiving system structure, respectively, Some of the key technologies are studied., blind parameter estimation technology, modulation blind identification techniques, stitching solution jump and suitable for blind receiver demodulation technology of the system.Firstly, this thesis studies the problem of parameter estimation in the blind receiver. Analysis of several commonly used frequency analysis method of characteristics and performance, design no cross term and the calculation efficiency of suitable short-time Fourier combined window time-frequency transform and use it as the basis for the back analysis of frequency hopped signal. Study on the speed estimation algorithm LS least squares algorithm and short-time Fourier transform window jump based on hybrid combination. In the jump time parameter estimation, peak search algorithm based on. Experiments show that the performance of the above two kinds of design algorithm and traditional method is more excellent than.Secondly, the modulation recognition technology in the blind receiver system is studied. In this paper, the composition of the modulation recognition system of the traditional communication signal is introduced, and the modulation recognition structure suitable for the frequency hopping blind receiver is designed. Based on time domain feature parameters and two kinds of recognition methods based on higher order statistics. In view of the analog signal, digital signal, analog digital mixed the three the study on modulation recognition, algorithm for spectrum peak salient features and high order statistic hybrid method is studied, the performance is good.In the end, the demodulation technique and the splicing of the blind receiving system are studied. The principle of frequency hopping is introduced, and the key technology of the process of joining the process is analyzed. In the design, in the traditional solution of hop link joined the carrier frequency fine adjustment process, study the frequency thinning algorithm based on the chirp Z transform to optimize the accuracy. According to the characteristics of frequency hopping communication, the receiver system is designed for the blind hop demodulation and non coherent demodulation structure. Finally, the system debugging, and feedback on the performance of the estimation and analysis of the above parameters. The results show that the algorithm can meet the requirement of the system.