volume | PIER Journals

Abstract

A systematic study of a low SLL (sidelobe level) two-way pattern in shared aperture arrays is presented. Three or two-weight excitations are used for the elements of the transmit and receive arrays depending on the requirements. The receive array has a smaller number of elements by not receiving from some of the edge elements of the transmit array. The condition of appearance of certain minor lobes of the transmit array pattern at certain nulls of the receive one helps to find the ratio between the number of elements of the receive and transmit arrays. In the case of more than one possible ratio, the optimum ratio is the one that gives the lowest SLL. In the three-weight array the total number of the transmit elements is equal to the that of the two higher excitations plus the number of elements of the highest one. In the two-weight excitation the higher weight elements of the transmit array are chosen to be approximately one half of the total elements. The excitations of both arrays are found by equating the level of the higher two unequal sidelobes of the two-way array factor. The three-weight array design is presented for the first time while the two-weight case gives lower peak SLL than those of the literature. Our work contains the important steps of the design and the main aspects of the implementation. The resulting peak SLL of the two-way array pattern reaches up to less than -51.2 dB and less than -56.5 dB, for the two- and three-weight cases, correspondingly.

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Professor Theodoros Samaras

Prof. John Sahalos