Research On Ranging Techniques In Radio Fuze System

This paper focuses on the research on ranging technology of the radio fuze system. Nonlinear frequency modulation (NLFM) whose modulation wave is the square of a saw wave is introduced into the fuze detection system. In this paper, the principle of the nonlinear frequency modulation system is expounded, the ambiguity function is deduced, a standard for parameter selection is proposed and the signal processing method is analyzed in detail. From this paper, it can be easily indicated that the nonlinear frequency modulation system has the advantages of low transmission power and low probability of interception. The profile of the ambiguity function is approximately perfect, and the main lobe of the range ambiguity function is very narrow. Accordingly, the system has high range resolution and excellent anti-jamming capabilities.Both the NLFM and LFM are single carrier radio fuze systems whose echoes do not have enough information for ranging. Consequently, a novel fuze system is proposed in this paper, incorporating both multi-carrier and linear frequency modulation. With the OFDM technology, the information redundancy in the echo of the system is increased. In this thesis, the waveform designing is discussed through the analysis on the ambiguity function of a ranging signal. And a method of echo processing is put forward. The multi-carrier fuze detection system is proved to be able to enhance the ranging resolution. Its combination with the linear frequency modulation diminishes the effect of leakage on ranging accuracy.