Impact of the Angular Velocity on the Signals Spectrum and Performance of Antenna-Array Receivers

Tremendous effort was previously made to estimate the location of moving sources with large angular velocities. However, to the best of our knowledge, no previous work has thoroughly investigated the effect of the combined angular velocity and mobile speed on the spectrum of the signal received by an antenna-array. In this contribution, we address this issue in the particular context of wideband CDMA transmission. We first show both by theoretical development and by simulations that the maximum frequency shift is the sum of the conventional Doppler term and a new term due to angular speed and that it is a linear function of both. We also show that the additional frequency shift due to the angular speed increases channel identification errors and thereby degrades the performance of antenna-array receivers. This performance loss becomes even higher at a larger number of antennas in the array.