Accuracy evaluation of DOA estimation with multi-band signals

The method to estimate direction of arrival (DOA) with multi-band signals is proposed in this paper. The MUSIC method, which is one of the conventional super-resolution DOA estimation methods, is applied to sets of snapshots filtered from the multi-band signal. In the beginning, a set of snapshots is extracted by the narrow-band filter (NBF) for the lowest frequency where the half wavelength of center frequency equals the array antenna spacing for a uniform linear array, and processed by the MUSIC method in order to avoid grating lobes. Next, using another set of snapshots in higher frequency, more precise DOA estimation is done in a narrower range with finer step angle. Therefore, this method can realize more accurate DOA estimation than the conventional method using a single set of snapshots. By examining RMSE and success probability of DOA detection, this method is compared with a conventional method.