Space-time Coding Of Frequency Hopping Anti-jamming System

In wireless communication environments, the reliability of received signals degrade seriously at the receiver, because of the inter symbol interference (ISI) caused by multipath fading channels and intentional or accidental jamming from other signals, such as partial-band noise jamming (PBNJ), multi-tone noise jamming (MTNJ) and follower jamming. Frequency-hopping (FH) technology for its excellent performance of anti-jamming and multiple access networks has become the mainstream of military anti-jamming communications technology. Compared with the fast frequency-hopping (FFH) technology, the slow frequency-hopping (SFH) technology can not get the frequency diversity gain. Therefore, in order to improve the performance of SFH transmission link, there is an urgent need to introduce diversity technology.The last ten years, more research attention to the design and performance analysis about a combination of multi-antenna receive diversity and SFH system. With the progress of multi-antenna transmit diversity technology, the combination of space-time coding (STC) and SFH system has become based on the multi-antenna signal processing and coding of the FH system as an important research direction. Among them, the space-time block coding (STBC), as well as space-frequency block coding (SFBC) and space-time-frequency block coding (STFBC) derived from STBC, because of their lower decoding complexity and providing multi-antenna diversity gain, have been extensive research.Therefore, the design methods and system performance of the SFH technology based on STBC are investigated in this thesis, as well as the corresponding performance simulation is investigated in a variety of fading and jamming channels. Analysis and discussion focus on the difference between the performance gain of the two system design.The first part, we give an overview of the status and progress of the FH and STBC, as well as the combination of multi-antenna technology and FH system, and indicate the main contribution of this thesis.The second part, the system model and signal model of FH system are detailedly summarized. According to the anti-fading performance study of SFH system and STBC system, the general system model and signal model about the combination of multi-antenna transmit technology and FH system are given, and we propose two system design of a SFH technology based on STBC: slow frequency-hopping - space-time block coding (SFH-STBC) system and slow frequency-hopping - space-time-frequency block coding (SFH-STFBC) system, as well as the design criteria for the combination of STC and SFH is given.The third part, the performance gain simulation are investigated and compared over jamming environments (PBNJ, MTNJ and follower jamming) and three types of fading channels, quasi-static fading, Rayleigh fading and multipath fading channels, and the schemes to increase the performance of the SFH technology based on STBC over multipath fading channels are proposed.Finally, some conclusion of the whole dissertation is drawn, and the further research issues and possible direction are pointed out.