Enhanced Sensitivity of CO Photoacoustic Sensors Using Empirical Mode Decomposition Denoising Algorithm

A CO sensor based on photoacoustic spectroscopy (PAS) with empirical mode decomposition (EMD) algorithm is investigated and demonstrated in this paper. In the PAS system, the complicated photo-thermal-acoustic conversion is a nonlinear and non-stationary process and contains various noise. In order to compensate the low signal-to-noise ratio (SNR), the EMD is introduced in the PAS system to deal with the photoacoustic signal. The experimental results show that a gain factor of similar to 3.0 on the SNR is achieved and the sensor has an excellent linear response to the gas concentration. The minimum detection level (MDL) for CO detection is reduced to 1.14 ppm with a 300 ms integrated time at room temperature and atmospheric pressure.

Automated summary

This paper investigates and demonstrates a CO sensor based on photoacoustic spectroscopy (PAS) with empirical mode decomposition (EMD) algorithm. The experimental results show that the sensor achieves a significant gain factor on the signal-to-noise ratio (SNR) and has an excellent linear response to the gas concentration. The minimum detection level (MDL) for CO detection can be reduced to 1.14 ppm at room temperature and atmospheric pressure with a 300 ms integrated time.