Design And Implementation Of Ultrashort Wave Adaptive Frequency Hopping Systems

Frequency-Hopping (FH) is a novel spread spectrum communication technique, which develops very fast in military field due to its LPI/LPD (Low Probability of Intercept / Detection) properties and immunity against interferences, The extensive application of HF/VHF (high frequency /very high frequency) frequency-hopping radios in military has greatly enhanced the ability of military equipments against jamming and interception and ensure the safety and validity of chain of military command.In recent years, with application of modern single processing technology, conventional FH station has could not fill the wants of anti-jamming and reliability in new war field circumstance. Modern military tactics cooperativity communication raises many new requirements including multi-mode, multi-band, and expandable performance, etc. So, developing new FH station has important sense in military strategy.Software radio that carries the device cooperation performance, repeatable programming, and system open performance has been a hot research direction. The main work of this paper is realizing a self-adaptation frequency hopping station adapting to new military requisition.Chapter 1 introduces the extensive application and general developing condition of HF/VHF communication and HF/VHF radios in military field. Then, we analyses the technical requkement and developing way of new military station. The last gives the target of this paper.Chapter 2 introduces the theory of frequency-hopping and GMSK, at the same time gives out a feasible method of FH synchronization and data transmission.Pointed to the shortage of conventional FH station in new war field circumstance, chapter 3 gives new realization ideas of self-adaptation frequency hopping (SFH). According to these ideas, data are transmitted with SFH mode or FCS mode or MIX of preceding mode. Against some avoidless jamming, forward error correction technology is used to raising the system dependability.Chapter 4 depictions the realization structure and state flows. In this chapter, the FH frame structure, synchronization method and the flows of SFH processing are expanded on. Then, paper presentations the system hard platform and the result of the first test. The last points out the tache that should be completed.