Radio frequency receiving front-end circuit

The invention discloses a radio frequency receiving front-end circuit, and belongs to the technical field of radio frequency receivers. Comprising a coupler, the input end of the coupler is connected with a front-end circuit, the output end of the coupler is connected with the input ends of a main branch and a coupling branch, and the output ends of the main branch and the coupling branch are connected with a combiner; the main branch is used for outputting a main branch intermodulation signal and a main branch harmonic signal, and the coupling branch is used for outputting a coupling branch intermodulation signal and a coupling branch harmonic signal; the main branch intermodulation signal and the coupling branch intermodulation signal have the same frequency and amplitude and opposite phases, and are subjected to intermodulation cancellation in the combiner; the branch harmonic signals and the coupling branch harmonic signals are the same in frequency and amplitude and opposite in phase, and harmonic cancel