Signal detection method and optical signal receiving system

摘要

The present invention provides a signal detection method, including: receiving, by a frequency mixer, wavelength division multiplexing signals and a local oscillator signal, where a wavelength of the local oscillator signal and a wavelength of a target signal in the wavelength division multiplexing signals are the same; a frequency mixer performs interference on the wavelength division multiplexing signals through the local oscillator signal to obtain a coherent signal formed by the local oscillator signal and the target signal; sending the coherent signal to a transimpedance amplifier for amplification to obtain a voltage signal; and obtaining the power of the target signal according to a power amplitude of the voltage signal.