Patent ID: 8521221

Claim:
A dual mode RF transceiver comprising: an antenna; a differential low noise amplifier (LNA) comprising a differential amplifier comprising an input to receive an RF signal from the antenna, wherein a frequency of the RF signal is within a first frequency band range in a first receiving mode, and is within a second frequency band range in a second receiving mode, where the frequency in the second frequency band range is twice of the frequency in the first frequency band range; and a differential inductor circuit coupled to a differential output of the differential amplifier and generating a differential amplified RF signal according to a first inductance in the first receiving mode and according to a second inductance in the second receiving mode, wherein the differential inductor circuit comprises four inductors, the four inductors are all in operation to provide the first inductance, and only two of the four inductors are in operation to provide the second inductance, the first inductance is larger than the second inductance; a local oscillator to generate a multiphase local oscillating (LO) signal having an oscillating frequency within the first frequency band range; and a dual mode differential mixer comprising a switch module; a plurality of fundamental mixers activated in the first receiving mode to generate a first differential baseband signal according to the multiphase LO signal from the local oscillator and the differential amplified RF signal; and a plurality of sub-harmonic mixers activated in the second receiving mode to generate a second differential baseband signal according to the multiphase LO signal from the local oscillator and the differential amplified RF signal.