Patent ID: 8909164

Claim:
A radio-frequency circuit comprising: an output operative to deliver a radio-frequency output signal; a control unit; a memory; an input operative to receive an input signal at a given reference frequency; and a phase-locked loop comprising a comparator having an output and a first input coupled to the radio-frequency circuit input; a filter having an output and an input coupled to the output of the comparator; a controlled frequency generator having an output coupled to the radio-frequency circuit output and an input coupled to the output of the filter; and wherein the comparator has a second input coupled to the output of the controlled frequency generator; wherein the memory stores a characteristic curve indicative of correlations between signal values measured at the filter output and reference frequency values at the comparator input, and wherein the control unit is arranged to determine an offset between an actual value of the reference frequency obtained on the basis of a measurement of the signal output from the filter and a theoretical value of said frequency known to the control unit, via the characteristic curve stored in the memory, and to control a correction of said offset.