Study On Frequency Hopping Sequences With Given Minimum Gap

The frequency hopping (FH) communication is one of spreading spectrum communication models. It's hopping carries frequencies are controlled by pseudo noise (PN) sequences. The FH communication is widely applied in modern military and civil communications because of its advantages such as anti-jamming, anti-fade, anti-capturing, channel sharing properties, and multi-access networking etc.The frequency hopping sequences design is one of the key points of the FH communication system. The properties of FH sequences including frequencies number, sequences families number, Hamming cross-correction, Hamming auto-correction, frequencies gap and frequencies proportional etc, have a direct influence on FH communication system's abilities of anti-jamming, anti-fade, anti-capturing, and mufti-access networking etc. The function of FH sequences is constructing frequency hopping pattern to control carries frequencies or play a role as address code in multi-access networking. Usually FH sequences are made over same residue, area of GF (pr), or chaos theory. There are many sequences that can be used in FH communication, such as m sequence, RS code, Gold code, M sequence, chaos sequence etc. And which sequence is chose to use in practice is decided by the intention of communication.In this thesis, these sequences topics related to the theory of FH communication systems are investigated, which are the theories of FH sequences, the theoretical bounds to sequence designs, the methods of sequence designs based on different sequences .And new constructive methods of designing FH sequences based on m sequence, RS code, chaos sequence, which are mainly improved the frequencies gap, are provided in this paper.In detail, this paper is made up of five parts. Firstly, the principle, main technical properties, advantages of FH communication, the status quo of FH communication system design and frequencies design are summarized. Secondly, the FH sequences' functions, properties, design demands and theories of FH frequences with given minimum gap are summarized and analyzed.Thirdly, a method to improve frequencies gaps, which is named nonlinear &mod d method, is provided. New ameliorated sequences are constructed, which are based on m sequences, used no continual model, and its prosperities is also be analyzed. In the fourth part, firstly, we designed a new non-repeating FH sequences based on (L,2)RS code. During the design proceeding, in order to resolve frequencies' in-equable interval, a new method is given! Then, a new method to construct non-repeating sequences with given minimum gap is given. And its prosperities is also be analyzed. In the last part, several classes of chaos maps and quantified methods are compared with and analyzed. A new method to design chaos FH frequencies, which is based on combined chaos maps and mid 2k-bites quantified, is provided. In order to improve the sequences' properties, an improved given gap method is also suggested. And the sequences' properties are summarized and analyzed.