HIGHLY LINEAR RECEIVER FRONT-END WITH THERMAL AND PHASE NOISE CANCELLATION

摘要

A radio receiver supporting cancellation of thermal and phase noise in a down-converted RF signal. An inbound RF signal and blocking signal are provided directly to a passive mixer for down-conversion into a first baseband signal having data, thermal noise, and reciprocal mixing (RM) noise components. The inbound signals are also provided to a transconductance circuit, the output of which is provided to a second passive mixer for conversion into a current signal having data and blocking signal components, and a RM image. The blocking signal component and the RM image are mixed with a second LO signal, derived from the blocking signal, to produce a RM noise cancellation signal. The data component of the current signal is converted into a second baseband signal having data and thermal noise components. The first baseband signal, second baseband signal and RM noise cancellation signal are then combined through harmonic recombination.

主权项

1. A wireless communication device comprising:
main signal path circuitry configured to receive a radio frequency (RF) signal at an RF node, the RF signal including a modulated RF signal and a blocking signal at a frequency offset Δfb, the main signal path circuitry including:
a first passive mixer configured to mix the RF signal and a first local oscillation (LO) signal to produce a down-converted RF signal; anda first amplifier circuit configured to convert the down-converted RF signal to a first baseband signal having a data component, a thermal noise component, and a reciprocal mixing (RM) noise component that is a product of reciprocal mixing of the blocking signal; a transconductance circuit coupled to the RF node and configured to convert the RF signal to a current signal; a second passive mixer configured to mix the current signal with the first LO signal to produce a down-converted current signal having a data component near DC, the down-converted current signal further having a blocking signal component near a frequency offset Δfb from the data component, and a RM image near a frequency offset 2Δfb from the data component; phase noise cancellation circuitry configured to mix the blocking signal component and the RM image of the down-converted current signal with a second LO signal to produce a RM noise cancellation signal; and harmonic recombination circuitry configured to combine the first baseband signal and the RM noise cancellation signal to cancel at least a portion of the RM noise component of the first baseband signal.