Direction finding with a circularly rotated antenna

A new algorithm for multiple emitter direction finding by using a single antenna moving along a circular trajectory is proposed. The problem is formulated by taking the Doppler frequency shift, caused by the movement of the antenna, into account, and by assuming that the information, hidden in the incoming signals, does not change in the observation duration. The proposed direction finding algorithm is, therefore, based on single snapshot processing and also on the linear prediction method developed by Tuncay Koc (see Ph.D. Dissertation, Middle East Technical University, Ankara, Turkey, 1996) and by Tuncay Koc and Tanik (see Signal Processing, vol.56, no.1, p.17-31, 1997). It has no restriction on the correlation of the incoming signals since it performs a single snapshot processing. The algorithm performance is investigated through computer simulations and it is observed that the root-mean-square errors of the direction of arrival estimates are less than one degree in most cases. Therefore, it seems reasonable to use the proposed direction finding algorithm in some particular applications, for instance, in identifying the environment for calibration purposes.