Simultaneous frequency and direction estimation from parallel-array data

A new method is proposed which provides the simultaneous estimation of both the centre frequency and the direction of arrival of multiple narrowband sources. Based on rotational-invariance techniques, the joint estimates are computed directly by appropriate processing of data from particular types of array instead of searching in a two-dimensional space. As a result, the computational efficiency is improved significantly. Some important scenarios are considered such as signals arriving from the same direction but having different centre frequencies distributed in a broadband frequency range. The potential capability are demonstrated by simulations.