RF front-end circuit and a low noise amplifier

The present invention provides an RF front-end circuit and a low noise amplifier, RF front-end circuit comprising a quadrature low noise amplifier and the passive mixer. Low noise amplifier may be provided two sets of the RF output signal to the differential quadrature passive mixer, the RF signal and the pilot signal down-yl differential quadrature phase differential phase baseband signal. RF front-end circuit configuration, does not require local oscillator quarter cycle generator circuit, to avoid interference with the phase channel and the quadrature phase channel signal and noise from each other.