When the radiating sources are located in the near-field of the antenna array, the aperture transition of signal wave fronts across the array can’t be ignored. Then the wave fronts of electromagnetic wave signal reaching the array should be described by the spherical wave model. This thesis carried out a series of researches about the inherent attribute of sensor array — near-field array manifold under this assumption. The mathematical model of manifold of N-elements array receiving near-field signals is constructed. Then the local characteristics of near-field array manifold are studied by using differential geometry. The mathematical expressions of the near-field array manifold arc length and the first-order curvature are given. Finally, the precision and resolution performance of near-field parameter estimation is analyzed by using these two local characteristic parameters.