Abstract：The ground-based experimental system for the interferometric passive microwave imager is designed to test its two-dimensional part correlation, imaging mechanism and algorithm. High spatial resolution is obtained by synthesis aperture technique. One measurement is required for one spatial frequency because the object locates in the far field of antennas of the experimental system. Moreover, the antenna array is revolving during the measurement. Therefore, a sparse aperture design is desirable for the antenna array in order to reduce cost and complexity of the whole system. This paper presents a sparse aperture design for the antenna array in the ground-based experimental system. The design objective is to use as few as possible antenna elements to obtain a similar covering of the spatial frequency domain. The numerical simulation results indicate that the engineering design requirements can be satisfied. Zero redundancy is realized for an array with 6 elements. The redundancy of an array with 7 elements is 9.1%. Moreover, sampling points of the designed antenna array cover completely the spatial frequency domain. Therefore, reliable visibility functions can be provided for brightness temperature image reversion.
2007, Vol. 25 
