关键词: 频率合成器, 宽带, 低相噪, PLL, GM4704

Abstract:

In order to meet the design requirement of the radar signal,this article describe a frequency synthesizer based on the decimal phase locked loop chip GM4704 made in China.The conventional PLL technique is adopted to generate low phase noise signal from 7.12 to 9.12 GHz.The design process and the related design parameters are given.Also we use the PLL simulation to design the loop band filter.Circuit tests show that the phase noise can reach to -97 dBc/Hz@1 kHz,which is close to the theoretical value;the spurious can reach -71 dB.

Key words: wide-band;low phase noise;PLL;GM4704