Performance Analysis of Doppler Shift Estimator Based on Level Crossing Rate

The Doppler shift estimation has impacts on the performance of vehicular communication systems. This paper analyzes the influence of algorithm parameter on the Doppler shift estimator based on level crossing rate (LCR), in which the level ratio is chosen as the analyzing parameter. Through the simulation with variant level ratios, signal-to-noise ratios (SNR) as well as the Doppler shifts (or vehicle speeds equivalently), this paper comprehensively analyzes the performance variation of Doppler shift estimator, and finds that higher SNRs lead to smaller estimation errors, while an optimal level ratio will further reduce the estimation error. Moreover, this paper also finds that the optimal level ratios are different for different vehicle speeds. Our studies will benefit the practice of LCR-based Doppler shit estimator.