Pseudo Code Phase Modulation Determined From The Applied Technology Research

The autocorrelation function of the pseudo code is similar to that of the white noise, which has the randomicity. The distance-determination technique by pseudo-random code just works on the basis of this characteristic. The pseudo-random code has excellent cut-off performance of the distance and strong anti-jamming capability. It has a broad application perspective. In this paper, some key techniques are discussed involved in designing the distance-determination system of the m-sequence phase modulation. The major work of the dissertation contains several points shown below:1. We introduce the trait of the pseudo-random code and the principle of the circuit of the distance-determination system. By using software named ISE6.2b and Xilinx's XC95144 CPLD we can build m-sequence generator and the digital correlator of m-sequece. By using the software ModelsimSE6.1b we simulate the program of VHDL.2. We introduce the structure and trait of Zero-IF Transceivers and Receivers and the theory of BPSK. By using the modulator AD8349 and demodulator AD8347 we can design the modulation circuit and demodulation circuit of the system.3. We introduce the structure and principle of PLL and discuss the spur of output frequency spectrum and the noise character of phase. By using the integrated Synthesizer and VCO ADF4360-0 we build the circuit of the frequency source.