Wavelet versus Fourier for wireless SAW sensors resonance frequency measurement

The purpose of this communication is to show that wavelet transform provides a relevant way to the Fourier transform in the case of central frequency measurement of a SAW resonator. After recalling the limits of the Fourier transform, we present a method based on wavelet transform modulus maxima which allows staying in the time domain without using the frequency domain. We show that this approach is a way to improve the spectral resolution and we propose a technique, checked on experimental signals, able to measure the SAW resonator frequency according to the desired spectral resolution.