System and method for correcting integral nonlinearity in an oscillator system
View Patent ↗A method may include measuring a frequency difference between an actual frequency and an expected frequency associated with a frequency control calibration signal value for each of a plurality of frequency control calibration signal values during a calibration phase. The method may additionally include generating integral non-linearity compensation values based on the frequency differences measured The method may further include generating the applied frequency control signal based on a frequency control calibration signal value received by the digital-to-analog converter during the calibration phase. The method may also include generating a compensated frequency control signal value based on a frequency control signal value received by the integral non-linearity compensation module and an integral non-linearity compensation value associated with the frequency control signal value during an operation phase of the wireless communication element.
1. A wireless communication element, comprising:
a receive path configured to receive a first wireless communication signal and convert the first wireless communication signal into a first digital signal based at least on an oscillator signal;
a transmit path configured to convert a second digital signal into a second wireless communication signal based at least on the oscillator signal and transmit the second wireless communication signal;
an oscillator configured to output the oscillator signal to at least one of the receive path and the transmit path, the oscillator configured to operate at an operating frequency based on an applied frequency control signal; and
a frequency control path configured to generate the applied frequency control signal, the frequency control path comprising:
a frequency estimator configured to, during a calibration phase of the wireless communication element, for each of a plurality of frequency control calibration signal values, estimate an actual frequency of the first digital signal;
an integral non-linearity detector configured to, during the calibration phase:
for each of the plurality of frequency control calibration signal values, measure a frequency difference between the actual frequency and an expected frequency associated with the frequency control calibration signal value; and
based on the frequency differences measured for the plurality of frequency control calibration signal values, generate integral non-linearity compensation values, each integral non-linearity compensation value associated with a corresponding possible frequency control signal value;
an integral non-linearity compensation module configured to, during an operation phase of the wireless communication element, generate a compensated frequency control signal value based on a frequency control signal value received by the integral non-linearity compensation module and an integral non-linearity compensation value associated with the frequency control signal value; and
a digital-to-analog converter configured to:
during the calibration phase, generate the applied frequency control signal based on a frequency control calibration signal value received by the digital-to-analog converter; and
during the operation phase, generate the applied frequency control signal based on the compensated frequency control signal value generated by the integral non-linearity compensation module.
2. The wireless communication element of claim 1 , wherein the frequency control signal value is an automatic frequency control code.
3. The wireless communication element of claim 1 , wherein each of the plurality of frequency control calibration signal values is an automatic frequency control code.
4. The wireless communication element of claim 1 , wherein the compensated frequency control signal value is an automatic frequency control code.
5. A system comprising:
a frequency estimator configured to, during a calibration phase of the system, for each of a plurality of frequency control calibration signal values, estimate an actual frequency of a digital receiver signal;
an integral non-linearity detector configured to, during the calibration phase:
for each of the plurality of frequency control calibration signal values, measure a frequency difference between the actual frequency and an expected frequency associated with the frequency control calibration signal value; and
based on the frequency differences measured for the plurality of frequency control calibration signal values, generate integral non-linearity compensation values, each integral non-linearity compensation value associated with a corresponding possible frequency control signal value;
an integral non-linearity compensation module configured to, during an operation phase of the system, generate a compensated frequency control signal value based on a frequency control signal value received by the integral non-linearity compensation module and an integral non-linearity compensation value associated with the frequency control signal value; and
a digital-to-analog converter configured to:
during the calibration phase, generate the applied frequency control signal based on a frequency control calibration signal value received by the digital-to-analog converter; and
during the operation phase, generate the applied frequency control signal based on the compensated frequency control signal value generated by the integral non-linearity compensation module.
6. The system of claim 5 , wherein the frequency control signal value is an automatic frequency control code.
7. The system of claim 5 , wherein each of the plurality of frequency control calibration signal values is an automatic frequency control code.
8. The system of claim 5 wherein the compensated frequency control signal value is an automatic frequency control code.
9. A method comprising:
estimating an actual frequency of a digital receiver signal for each of a plurality of frequency control calibration signal values during a calibration phase of a wireless communication element, estimate an actual frequency of a digital receiver signal;
measuring a frequency difference between the actual frequency and an expected frequency associated with the frequency control calibration signal value for each of the plurality of frequency control calibration signal values during the calibration phase;
generating integral non-linearity compensation values based on the frequency differences measured for the plurality of frequency control calibration signal values during the calibration phase, each integral non-linearity compensation value associated with a corresponding possible frequency control signal value;
generating the applied frequency control signal based on a frequency control calibration signal value received by the digital-to-analog converter during the calibration phase;
generating a compensated frequency control signal value based on a frequency control signal value received by the integral non-linearity compensation module and an integral non-linearity compensation value associated with the frequency control signal value during an operation phase of the wireless communication element; and
generating the applied frequency control signal based on the compensated frequency control signal value generated by the integral non-linearity compensation module during the operation phase.
10. The method of claim 9 , wherein the frequency control signal value is an automatic frequency control code.
11. The method of claim 9 , wherein each of the plurality of frequency control calibration signal values is an automatic frequency control code.
12. The method of claim 9 wherein the compensated frequency control signal value is an automatic frequency control code.