Linear Frequency Diverse Array Manifold Geometry and Ambiguity Analysis

Different from phased-array, frequency diverse array (FDA) offers range-dependent beampattern and thus provides new application potentials. But, there is a fundamental question: what is the FDA manifold geometric and ambiguity properties? In this paper, the FDA manifold geometric and ambiguity properties are investigated via manifold geometry analysis; the FDA resolution and detection capabilities are derived as a function of the manifold length and first curvature for the sources with unequal powers. The ambiguities inherent in a linear FDA manifold is investigated. Under the same conditions, FDA has better detection and resolution capabilities than conventional phased array. Since FDA offers a range-dependent beampattern, some of the manifold vectors that are linearly dependent in phased array, will became linearly independent in FDA. For these reasons, when compared to a phased-array radar, FDA radar can resolve more sources. All the derived expressions are validated by the extensive simulation results.