The front-end amplifier for optical receiver is made up of two important circuits: preamplifier and main amplifier.

光接收机前端放大电路主要由两个关键电路构成：前置放大器和主放大器。

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Since most commercial (COTS) devices for the radio communications industry are normally 50 ohms intrinsic impedance, there will be problems with proper matching of the main power amplifier and the receiver front end.

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