一、概述在雷达半主动导引头中,为了获得时间(脉冲体制系统)和频率基准(连续波系统),往往需要一个直波系统。有了它,脉冲体制的导引头可以获得同步时间基准,从而产生“封闭门”和“距离跟踪波门”,前者对泄漏信号及地物杂波进行封闭,后者完成选择和跟踪目标的目的;连续波体制的导引头可以获得频率基准,从而提取出活动目标的多普勒频率,完成从杂波中选择和跟踪目标的目的。近年来,随着科学技术的发展及其对导引头制导精度的提高,就要求人们充分利用和扩大直波通道的功能来提高整个武器系统的战术性能。国外许多导引头在这方面作了不少工作,以期提高系统的低空性能和抗干扰能力,如英国的“海标枪”和美国的“不死鸟”导引头等。但我们在这方面作的工作很少,有关这方面的情报资料 I. Overview In radar semi-active seeker, in order to obtain time (impulse system) and frequency reference (continuous wave system), a direct wave system is often required. With it, the seeker of the impulsive system can obtain a synchronized time base, resulting in a “closed door” and a “distance-tracking” gate, the former closing leaks and clutter, which completes the selection and tracking of targets The purpose of continuous wave system seeker can get the frequency reference, so as to extract the Doppler frequency of the moving target and accomplish the goal of selecting and tracking the target from the clutter. In recent years, with the development of science and technology and the improvement of seeker guidance accuracy, people are required to make full use of and expand the function of direct wave channel to improve the tactical performance of the whole weapon system. Many foreign seeders have done a lot of work in this regard, with a view to improve the system’s low altitude performance and anti-jamming capabilities, such as the British “sea javelin” and the United States “Phoenix” seeker and so on. However, we have rarely done any work in this area and we have intelligence information on this issue