1.概述最易产生公共台互调的原因之一是在一般发射机的丙类输出级。这种放大器的非线性特点是众所周知的。在功率电平较高时,从第二个信源馈入这一级不太大的无用信号也会引起不希望的混合,导致在有关频率上产生寄生信号。能够产生这种混合的公共台发射机间的耦合,在各天线间、馈线间(特别是在驻波比过大时)及设备间都会存在。可通过精心的工程设计减小耦合,但是,通常还是会有耦合足以 1. Overview One of the reasons that most common-platform intermodulation is common is in the Class C output stage of a typical transmitter. The nonlinear characteristics of this amplifier are well known. When the power level is high, feeding this not-so-large, unwanted signal from the second source can also cause undesirable mixing, resulting in parasitic signals at the relevant frequency. Coupling between common station transmitters that can produce this mix can exist between antennas, between feeders (especially when the standing wave ratio is too large), and between devices. Coupling can be reduced by careful engineering, but usually enough coupling will suffice