Apparatus and method for phase tracking an oscillatory signal
AssigneeOxford University Innovation Limited
InventorsColin Gerard MCNAMARA, Andrew David SHAROTT
Life of this patent
Estimating the term…
Abstract
Apparatus and methods for phase tracking an oscillatory signal are provided. In one arrangement, an input signal is received. First and second reference oscillatory signals are received at the frequency of a target frequency component of the input signal. The first and second reference oscillatory signals are phase shifted relative to each other. Weights of a weighted sum of the first and second reference oscillatory signals are iteratively varied to match the weighted sum to the input signal. The weights of the matched weighted sum are used to provide real time estimates of the phase of the target frequency component of the input signal.
Claims31
An apparatus for phase tracking an oscillatory signal, comprising:
- an input unit configured to receive an input signal;
- and
- a phase estimation unit, wherein the phase estimation unit is configured to:
- generate first and second reference oscillatory signals at the frequency of a target frequency component of the input signal, the first and second reference oscillatory signals being phase shifted relative to each other;
- iteratively vary weights of a weighted sum of the first and second reference oscillatory signals to match the weighted sum to the input signal;
- and
- use the weights of the matched weighted sum to provide real time estimates of the phase of the target frequency component of the input signal.
(canceled)
7-8. (canceled)
(canceled)
12-13. (canceled)
The apparatus of 11 wherein:
- the look-up table stores values associated with time points spanning only a portion of the period of the first reference oscillatory signal and the second reference oscillatory signal;
- and
- the phase estimation unit is configured to use symmetry of the first reference oscillatory signal and the second reference oscillatory signal to generate values for time points spanning all of the period of the first reference oscillatory signal and the second reference oscillatory signal based on the values stored in the look-up table.
(canceled)
The apparatus of 1, wherein
- the phase estimation unit is configured to output data representing when the estimated phase passes through a predetermined phase threshold or into a predetermined phase range in each of at least a subset of cycles of the target frequency component of the input signal, and
- the phase estimation unit is further configured to:
- determine, for each passing of the estimated phase through the predetermined phase threshold or into the predetermined phase range, whether the estimated phase has passed through the predetermined phase threshold or into the predetermined phase range within a time period shorter than a predetermined fraction of a period of the target frequency component since a preceding passing of the estimated phase through the predetermined phase threshold or into the predetermined phase range;
- and
- output data representing a result of the determination.
(canceled)
An apparatus for phase tracking an oscillatory signal, comprising:
- an input unit configured to receive an input signal;
- and
- a phase estimation unit configured to output data representing when an estimated phase of a target frequency component of the input signal passes through a predetermined phase threshold or into a predetermined phase range in each of at least a subset of cycles of the target frequency component of the input signal, wherein:
- the phase estimation unit is further configured to:
- determine, for each passing of the estimated phase through the predetermined phase threshold or into the predetermined phase range, whether the estimated phase has passed through the predetermined phase threshold or into the predetermined phase range within a time period shorter than a predetermined fraction of a period of the target frequency component since a preceding passing of the estimated phase through the predetermined phase threshold or into the predetermined phase range;
- and
- output data representing a result of the determination.
(canceled)
The apparatus of claim , wherein the selected proportion is selected based on a ratio of the number of non-standard instances to the number of standard instances in a preceding time window.
29-30. (canceled)
A method of phase tracking an oscillatory signal, comprising:
- receiving an input signal;
- generating first and second reference oscillatory signals at the frequency of a target frequency component of the input signal, the first and second reference oscillatory signals being phase shifted relative to each other;
- iteratively varying weights of a weighted sum of the first and second reference oscillatory signals to match the weighted sum to the input signal;
- and
- using the weights of the matched weighted sum to provide real time estimates of the phase of the target frequency component of the input signal.
A method of phase tracking an oscillatory signal, comprising:
- receiving an input signal;
- determining when an estimated phase of a target frequency component of the input signal passes through a predetermined phase threshold or into a predetermined phase range in each of at least a subset of cycles of the target frequency component of the input signal;
- and
- determining, for each passing of the estimated phase through the predetermined phase threshold or into the predetermined phase range, whether the estimated phase has passed through the predetermined phase threshold or into the predetermined phase range within a time period shorter than a predetermined fraction of a period of the target frequency component since a preceding passing of the estimated phase through the predetermined phase threshold or into the predetermined phase range;
- and
- outputting data representing a result of the determination.
33-35. (canceled)
Dependencies are inferred from the claim text.