Mathematical Derivation and Parameter Analysis of Phase-sensitive Detection Principle

Phase-sensitive detection is an effective method for high-precision detection of weak signals, but there is no detailed derivation and description of this principle in the previous literatures. This article based on the basic principle of phase-sensitive detection gives two different derivation methods of analog and digital phase-sensitive detection principles. Then the Matlab is used to verify the digital phase-sensitive detection principle and analyze the parameters. Finally, this article gives a reasonable range of parameter selection for phase-sensitive detection and guides the reader to make a good parameter selection when using phase-sensitive detection.