Crosstalk suppression of extrinsic Fabry-Perot interferometric sensor array based on five-step phase shift...

Area of Science:

• Optical Sensing
• Interferometry
• Signal Processing

Background:

• Extrinsic Fabry-Perot Interferometric (EFPI) sensors are crucial for various sensing applications.
• Crosstalk between elements in EFPI sensor arrays degrades system performance and accuracy.
• Existing demodulation schemes often struggle with effective crosstalk suppression in multiplexed arrays.

Purpose of the Study:

• To propose and validate a novel multiwavelength averaging method for crosstalk suppression in EFPI sensor arrays.
• To investigate the effectiveness of the proposed scheme in a two-element EFPI sensing system.
• To demonstrate the scheme's advantages over conventional single-wavelength methods.

Main Methods:

• Development of a five-step phase shift demodulation scheme incorporating multiwavelength averaging.
• Theoretical analysis of crosstalk suppression mechanisms.
• Validation through numerical simulations and experimental testing under varying parameters.

Main Results:

• The multiwavelength averaging scheme demonstrated superior crosstalk suppression compared to single-wavelength methods.
• Effective crosstalk reduction was achieved even when EFPI sensor elements had unequal cavity lengths.
• The proposed method showed reduced dependency on extinction ratio, enhancing robustness.

Conclusions:

• The proposed multiwavelength demodulation scheme offers a significant advancement in suppressing crosstalk in EFPI sensor arrays.
• This method alleviates the need for precisely matched cavity lengths, simplifying array design.
• The technique holds potential for large-scale optical sensing systems, such as hydrophone arrays.