Shared-aperture Ku/Ka bands microstrip array feeds of parabolic cylindrical reflector antenna have been developed. Dualpolarized microstrip crossed slots, fed by inverted microstrip lines, are used as Ku-band antennas. Single-polarized square microstrip patches, fed by microstrip lines, are used as Ka-band antennas. The Ka-band microstrip patches are in the upper layer and interlaced with the Ku-band microstrip slots . By sharing the same antenna aperture, the problem of placing two feeds at a focus has been solved. The measured results of 8 Ku-band and 16 Ka-band linear arrays are presented and discussed in detail. The array is modular in form and can be easily scaled to larger aperture.

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This article presents a novel structure of integrated radio frequency(RF) internal calibration line for patch antenna without increasing the antenna profile. The RF internal calibration line is realized by introducing a microstrip line in the middle of the nonradiation side of the two patch antenna units. Metalized grounding strips (MGS) are composed of metal strips on the upper surface of printed circuit board, metalized ground vias, and the ground layer. The MGS with gaps is set between the calibration line and the antenna units to adjust the mutual coupling. A 16 Â 32 antenna array is fabricated and measured for verification. The measured results are in good agreement with the theoretical simulation. It shows that the mutual coupling between the coupling port of the calibration line and each port of the antenna unit is between À32.5 and À27 dB in the X and Ku frequency band (12-13.2 GHz, 9.5% relative bandwidth), and the antenna pattern is not distorted by the integrated calibration lines.

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An improved wideband cavity-backed antenna and a planar phased array with wideband wide-angle impedance matching (WAIM) are provided in this paper. A step-shaped cavity is applied in the antenna, so the relative bandwidth of VSWR < 2 can be improved to more than 52% without increasing the cavity profile. Furthermore, a planar phased array constructed by the cavity-backed antenna can work with a wide-angle scanning range of ±60 • at both Eand H-planes. Due to the wideangle scanning range, the impedance matching for the phased array will be unstable in the required wideband. Consequently, the matching layer with metamaterials has been loaded on the phased array. The VSWR is controlled within 2 in E-plane and 3.5 in H-plane during the scanning range of ±60 • in wide bandwidth.