下变频和上变频功能在大多数高频接收机和发射机中经常是以常常被忽略的元件-射频/微波混频器的方式实现的。在过去20多年中,混频器的外观发生了很大的变化,如今的封装类型种类也非常繁多。不过,它们的主要功能没有改变:即将一个信号(通常通过调制携带有某种信息)的频率转换成(比原始频 The downconversion and upconversion functions are often implemented in most high-frequency receivers and transmitters as often overlooked components - RF / microwave mixers. Over the past two decades, the appearance of mixers has changed dramatically, and the types of packages available today are numerous. However, their main function has not changed: the frequency of a signal (usually carried by modulation) is converted to (than the original frequency