Patent ID: 6885853

Claim:
A radio-frequency receiver having an integrated circuit IF filter, said radio-frequency receiver comprising: a semiconductor substrate; a downconversion mixer having an input and an output; a tunable local oscillator coupled to said mixer input; an intermediate frequency filter having an input coupled to said mixer output, said intermediate frequency filter being formed on said semiconductor substrate using a resistor-forming semiconductor process; a process-variant circuit having an input and an output, said process-variant circuit being formed on said semiconductor substrate using said resistor-forming semiconductor process; and a control circuit having an output and an input coupled to said process-variant circuit input and output, respectively, and having an output coupled to said tunable local oscillator, said control circuit being configured to initialize said process-variant circuit, then monitor performance of said process-variant circuit and determine a tuning parameter for said tunable local oscillator based upon said performance of said process-variant circuit.