Precise frequency generation for low duty cycle transceivers using a single crystal oscillator

A transceiver unit, comprising:

• a first oscillator circuit for providing a first clock signal;
• a second oscillator circuit for providing a second clock signal;
• a crystal associated with the second oscillator circuit for controlling the provision of the second clock signal;
• a transceiver for transceiving data from the transceiving unit;
• and
• a controller configured to:
• establish a time base based upon oscillations of the crystal;
• compare a number of oscillations for the non-crystal oscillator and the crystal oscillator during a known time period;
• determine an adjustment based upon the established time base and the compared number of oscillations;
• and
• control operation of the transceiver responsive to the adjustment.

A method for calibrating a non-crystal oscillator in a unit using a crystal oscillator, comprising the steps of:

• establishing a time base based upon oscillations of the crystal oscillator;
• comparing a number of oscillations for the non-crystal oscillator and the crystal oscillator during a known time period;
• determining a frequency for the non-crystal oscillator in the transceiver unit based upon the established time base and the compared number of oscillations;
• changing the frequency of the non-crystal oscillator to approximately equal a target frequency based upon an oscillation frequency of the crystal oscillator;
• determining a number of pulses of the non-crystal oscillator during the known time period based upon the established time base and the compared number of oscillations;
• changing a second number of pulses measured by a timer to approximately equal the determined number of pulses;
• operating the transceiver unit based upon the target frequency and the second number of pulses.