Patent ID: 8229386

Claim:
A receiver applied to a satellite down converter, the receiver comprising: a radio frequency metal-oxide-semiconductor amplifier for receiving and amplifying a signal of a first band and a signal of a second band of a satellite microwave band from an external antenna circuit according to a control signal, the radio frequency metal-oxide-semiconductor amplifier comprising: a matching circuit having a first terminal coupled to the external antenna circuit, a second terminal, and a third terminal coupled to ground, wherein the matching circuit is used for matching the radio frequency metal-oxide-semiconductor amplifier and the external antenna circuit, and for receiving the signal of the first band and the signal of the second band; an N-type metal-oxide-semiconductor transistor having a first terminal, a second terminal coupled to the matching circuit, and a third terminal coupled to the ground, wherein the N-type metal-oxide-semiconductor transistor is used for amplifying the signal of the first band and the signal of the second band; a first inductor having a first terminal for receiving a first voltage, and a second terminal coupled to the first terminal of the N-type metal-oxide-semiconductor transistor; a first switch having a first terminal coupled to the second terminal of the first inductor, a second terminal for receiving the control signal, and a third terminal; and a first capacitor having a first terminal coupled to the third terminal of the first switch, and a second terminal coupled to the ground; wherein when the first switch is turned on according to the control signal, the matching circuit receives the signal of the first band according to a resonant frequency of the first inductor and the first capacitor, and when the first switch is turned off according to the control signal, the matching circuit receives the signal of the second band according to a resonant frequency of the first inductor and a parasitic capacitor; a mixer coupled to the radio frequency metal-oxide-semiconductor amplifier for converting the signal of the first band into a signal of a first intermediate frequency band according to a first oscillation frequency of a local oscillator, or converting the signal of the second band into a signal of a second intermediate frequency band according to a second oscillation frequency of the local oscillator; and an intermediate frequency amplifier coupled to the mixer for amplifying and outputting the signal of the first intermediate frequency band and the signal of the second intermediate frequency band.