Doppler Estimation of Multicarrier Acoustic Signals Based on the Accordance of Complex Amplitude Estimates

In positioning and communication systems utilizing multicarrier acoustic signals composed of multiple sinusoidal waves, the performance degradation arises due to Doppler shifts caused by receiver motion. Consequently, it is essential to estimate the magnitude of the Doppler shift while simultaneously mitigating the influence of multipath propagation. To address this challenge, the proposed method extracts the segment of the received signal prior to the arrival of multipath components and identifies the concordance point of two sets of complex amplitude groups obtained using the extracted signal and two sets of reference signal groups. This approach reduces the computational burden by minimizing the number of multiplications required during the search process, enabling efficient estimation with lower complexity compared with conventional methods that search through reference signals. Evaluation experiments demonstrated that, when moving a microphone at velocities ranging from −2.0 to 2.0 m/s, the proposed method achieved Doppler shift estimation with a standard deviation of less than 0.064 m/s at signal-to-noise ratios (SNRs) of 21.2 dB or higher.