摘要
基于宽带接收机中不同相位噪声的宽带本振对接收噪声系数的影响分析,通过不同相位噪声的宽带本振对混频器变频噪声系数的测试与对比,得出混频器中频信号相位噪声主要由本振相位噪声决定,变频噪声系数的恶化主要由宽带本振500 kHz外的远端噪声恶化所引起的结论。结合宽带接收机前段增益与变频噪声对接收链路噪声系数的仿真计算,灵敏度越高的宽带接收机对本振远端相位噪声恶化越敏感。对于高灵敏度的宽带接收机,为了避免宽带本振相位噪声引起链路噪声系数恶化,宽带接收前端在混频之前的增益需要大于25 dB。
Based on the analysis of the influence of wide-band local oscillator with different phase noise on the received noise figure of the wideband receiver,a wideband mixer is used to actually test to obtain the phase noise of the mixer IF signal,through the comparison of the frequency conversion noise figure of the IF signal with different phase noise of wideband local oscillator,the phase noise of the mixer IF signal is mainly determined by the phase noise of the local oscillator.The deterioration of the variable-frequency noise coefficient is mainly caused by the deterioration of the far-end noise outside the broadband local oscillator of 500 kHz.At the same time,combined with the gain calculation of the front-end gain and the variable-frequency noise of the wideband receiver,the broadband receiver with higher sensitivity is more sensitive to the deterioration of the phase noise.For high-sensitivity wideband receivers,in order to avoid noise figure degradation caused by wideband local oscillator phase noise,the gain of the receive front end before mixing needs to be greater than 25 dB.
作者
李夏琴
Li Xiaqin(Southwest China Institute of Electronic Technology,Chengdu 610036,China)
出处
《电子技术应用》
2020年第2期36-42,47,共8页
Application of Electronic Technique
关键词
宽带接收机
相位噪声
宽带本振
噪声系数
broadband receiver
phase noise
broadband local oscillator
noise figure
