High resolution of synthetic aperture techniques for a moving array transmitting orthogonal signals

The element-space synthesizing aperture before matched filtering and matched filtering before beam-space synthesizing aperture for target bearing estimation by a moving array transmitting orthogonal signals are proposed, which are designated as ESSA-MF method and MF-BSSA method in this paper, respectively. The orthogonal signal transmission enables a moving array to perform matched filtering before synthetic aperture processing or after, which both lead to virtual and synthetical extension of the array aperture and therefore provide superior performance of target bearing resolution, compared to coherent signal transmission mode. Numerical results show that amoving array in orthogonal signal transmission mode provides higher bearing resolution based on synthetic aperture techniques than its traditional coherent signal transmission mode.