Design And Application For The FH-OFDM Communications Systems Of Frequency Hopping Sequence

Since 80's in 20 centuies, theorthogonal frequency-division multiplexing (OFDM) has got an extersive application in the public communications aspect. At the same time, the frequency-hopping(FH) technique has already got an extensive application in civil mobile communications,due to its extelleent performance.For improving existent shortage of the FH communications systems, it appeases a kind of communications system-FH-OFDM communications system to realize frequency hopping communication.The FH-OFDM communications systems proposed in the paper has some advantages,such as the abilities to improve the frequency hopping rate,to increase the rate of information transmission,and to improve the efficiency of frequency spectrum with no difficulty.It is the key of frequency hopping communication system to design frequency hopping sequence.The properties of frequency hopping sequence affect the performance of The FH-OFDM communications systems.it is discussed that the forming methods of frequency hopping pattern based on m-sequence, RS-code in paper. The part introduoces methods of several chaotic maps, and analyzes the characteristics of chaotic hopping sequence by the maps. We can make use of the nonlinear inverted way estimating original value of chaotic hopping sequence thet produce by single map. We suggest a kind of method of generating chaotic FH sequences through combined map for improving secret capability of communication.It is introduced that the method of dual frequency band and smoothed substitution. It is introduced that the design of multi-carriers frequency hopping sequence. It is introduced that the concept and the advantage of FFH-OFDM systems.We apply them to FH communication system.In the end,we analyze the simulative result by MATLAB.