US 12,329,532 B2
Apparatus and method for phase tracking an oscillatory signal
Colin Gerard McNamara, Oxford (GB); and Andrew David Sharott, Oxford (GB)
Assigned to OXFORD UNIVERSITY INNOVATION LIMITED, Oxford (GB)
Appl. No. 17/437,869
Filed by Oxford University Innovation Limited, Oxford (GB)
PCT Filed Mar. 10, 2020, PCT No. PCT/GB2020/050576
§ 371(c)(1), (2) Date Sep. 10, 2021,
PCT Pub. No. WO2020/183152, PCT Pub. Date Sep. 17, 2020.
Claims priority of application No. 1903363 (GB), filed on Mar. 12, 2019.
Prior Publication US 2022/0183612 A1, Jun. 16, 2022
Int. Cl. A61B 5/374 (2021.01); A61B 5/397 (2021.01); A61N 1/05 (2006.01); A61N 1/36 (2006.01); G01R 23/12 (2006.01); G01R 23/18 (2006.01); G06F 1/03 (2006.01)
CPC A61B 5/374 (2021.01) [A61B 5/397 (2021.01); A61N 1/0529 (2013.01); A61N 1/36139 (2013.01); G06F 1/0335 (2013.01); G01R 23/12 (2013.01); G01R 23/18 (2013.01)] 22 Claims
OG exemplary drawing
 
1. 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.
 
15. 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.