Doppler Estimation Based on Doppler-Invariant Signals

In this letter, we propose a Doppler estimation method with low complexity and high accuracy based on Doppler-invariant signals. In consideration of the Doppler invariant property, the general expression of the Doppler-invariant signals is deduced on the basis of mathematical model. Furthermore, the approximate expression of signal frequency spectrum is given by stationary phase principle. Due to its signal properties, the proposed method utilizes two specific waveforms for Doppler estimation. In practical applications, only three matched filters are required in the time domain. The parameter selection of the source signals is studied through theoretical analysis. The simulation experiments confirm the validity of the parameter analysis. In comparison with the existing method, the proposed method provides better performance in noisy environments.