前言组合波干扰是超外差接收机、频率合成器中必然碰到的一个问题。国外在这方面进行了不少工作,大致有如下三种方法。(一) 直接计算法。(二) 查表法。(三) 图解法。三种方法各有长短,图解法能了解全貌,直观,但不准确。计算法准确,但看不出全貌,不直观。所以实用中总是二种方法兼而用之,以取长补短。现有的图解法有个通病,就是作图麻烦,需要作 Pre-combination wave interference is superheterodyne receiver, frequency synthesizer inevitable encounter a problem. Many foreign countries have done a lot of work in this area. There are roughly three methods as follows. (A) direct calculation method. (B) look-up table. (C) graphic method. The three methods have their own length, graphic method can understand the whole picture, intuitive, but not accurate. The calculation method is accurate, but can not see the whole picture, not intuitive. So there are always two ways to use it in practice, so as to complement each other’s strengths and weaknesses. The existing diagram has a common problem, is drawing trouble, need to be done