High speed sampling of sensors
AssigneeStingray Geophysical Hong Kong Limited
InventorJulian Fells
Life of this patent
Estimating the term…
Abstract
Systems and methods for interrogating sensing systems utilising bursts of samples. Bursts of samples correspond to optical pulses returning from optical sensors, where pulses are spaced at a period significantly longer than the pulse width, giving irregular sample spacing. The interrogation system and method processes the irregular busts of samples to recover phase information from received signals.
Claims20
A method of interrogating an optical sensing system performed at an interrogation system, comprising the steps of:
- receiving a plurality of bursts of samples of an optical signal, each burst of samples comprising a plurality of samples of each pulse in a group of discrete optical pulses, wherein the groups are regularly spaced in time with a group repetition period larger than the group width, and the optical pulses comprise a phase modulated signal;
- processing the bursts of samples to obtain a series of regularly spaced samples wherein processing the bursts of samples comprises processing the samples utilising a filter bank, the filter bank comprising a number of parallel paths equal to the number of samples in each burst;
- and
- demodulating the regularly spaced samples to retrieve the phase information from the detected pulses.
A method of interrogating an optical sensing system performed at an interrogation system, comprising the steps of:
- receiving a plurality of bursts of samples of an optical signal, each burst of samples comprising a plurality of samples of each pulse in a group of discrete optical pulses, wherein the groups are regularly spaced in time with a group repetition period larger than the group width, and the optical pulses comprise a phase modulated signal;
- processing the bursts of samples to obtain a series of regularly spaced samples;
- and
- demodulating the regularly spaced samples to retrieve the phase information from the detected pulses, wherein the step of processing comprises the steps of downsampling the received samples, upsampling the downsampled samples, filtering the upsampled samples, and combining the filtered samples, and wherein the downsampling ratio is equal to the sample rate in each burst divided by the group repetition frequency.
A method of interrogating an optical sensing system performed at an interrogation system, comprising the steps of:
- receiving a plurality of bursts of samples of an optical signal, each burst of samples comprising a plurality of samples of each pulse in a group of discrete optical pulses, wherein the groups are regularly spaced in time with a group repetition period larger than the group width, and the optical pulses comprise a phase modulated signal;
- processing the bursts of samples to obtain a series of regularly spaced samples;
- and
- demodulating the regularly spaced samples to retrieve the phase information from the detected pulses, wherein the step of processing comprises the steps of downsampling the received samples, upsampling the downsampled samples, filtering the upsampled samples, and combining the filtered samples, and wherein the upsampling is performed at a rate of the group width multiplied by the sample rate in each burst.
Dependencies are inferred from the claim text.