DOA ambiguity vs. array configuration for supbspace-based DF methods

In this paper, we investigated the DOA (direction-of-arrival) ambiguity of an arbitrary array for subspace-based DF (direction finding) methods in a wide frequency band. The ambiguities are divided into different orders. First order ambiguity is intensively discussed. A general conclusion on first-order ambiguity vs. array configuration is reached. Especially, the ULA (uniform linear array) and UCA (uniform circular array) are examined. Simulation results are also presented.