Patent ID: 6023198
Filing Date: 2000-02-08
Classification: H03L

Abstract:
A method of self-tuning a voltage controlled oscillator (VCO) circuit in a radio, comprising the steps of:internally measuring the radio's initial temperature;storing the radio's initial temperature;initializing a programmable voltage;applying the programmable voltage to the VCO to tune the VCO;applying a control voltage to the VCO to lock the VCO;determining if the VCO is in a locked condition;measuring the control voltage internally to the radio if the VCO is in a locked condition;comparing the control voltage of the VCO in the locked condition to a predetermined control voltage range stored in the radio;automatically adjusting the programmable voltage if the VCO is in an unlocked condition or if the control voltage does not fall within the predetermined control voltage range;repeating the steps of determining, measuring, comparing, and automatically adjusting, until the VCO is locked and the control voltage falls within the predetermined control voltage range;monitoring the radio temperature when the VCO is locked and the control voltage falls within the predetermined control voltage range;calculating the difference between the radio's initial temperature and the monitored temperature to determine whether a predetermined delta temperature threshold has been reached; andreturning to the step of determining, if a predetermined temperature threshold has been reached.