X波段低相噪宽频带雷达频率综合器设计

Design of X broadband and low phase noise radar frequency synthesizer

随着雷达导引头在弹载方面的广泛应用,导引头的抗电子干扰能力成为一项关键技术。雷达频率综合器作为雷达系统的核心部件,其产生本振信号的质量对雷达系统的抗电子干扰能力具有决定性影响,这对本振信号的跳频带宽、相位噪声、杂波抑制度、平坦度等参数指标提出了更高的要求。本文运用直接数字频率合成(DDS)技术和先进设计系统(ADS)仿真技术进行宽带阻抗匹配,采取有效信号串扰隔离技术,使雷达频率综合器的X波段本振信号的各项指标得到明显改善。通过实验测试,本振信号可以实现快速跳频,跳频带宽达到500 MHz,提高了雷达的抗干扰能力;相位噪声优于-98 dBc/Hz@1 kHz,有效改善了雷达导引头的接收灵敏度。

With the wide application of radar seeker on missile,the anti-jamming capability of the seeker is a key technology.The radar frequency synthesizer is the core part of radar system.The quality of local oscillator signal generated by radar frequency synthesizer shows a critical impact on the radar system’s ability of confrontation and anti-confrontation.Therefore,it proposes higher requests on the parameters of the local oscillator signal including wideband hopping,phase noise,clutter suppression,flatness and so on.Based on Direct Digital Synthesizer(DDS)technology and Advanced Design System(ADS)simulation technology,broadband impedance matching is performed.The effective signal crosstalk isolation technology is adopted to improve the indexes of X-band local oscillator signal of the radar frequency synthesizer.Through experimental testing,the local oscillator signal can achieve fast frequency hopping,and the frequency hopping bandwidth reaches 500 MHz,which improves the antiinterference capability of the radar;the phase noise is better than-98 dBc/Hz@1 kHz,which effectively improves the receiving sensitivity of the radar seeker.