Ku-band wideband space-borne waveguide slot array antenna

Ku-band wideband high gain space-borne waveguide slot array antenna optimized by genetic algorithms is presented. Wide bandwidth is ensured by utilizing E-T wideband power divider and partition feed distribution of the array. Respects referring to higher modes, slot couplings, slot end shapes and other factors are given fully consideration in design process. Precision processing and salt bath brazing are employed to maintain the good conformity with respect to aperture shape, besides, high strength is also guaranteed. Two factors mentioned above play an important role for the possible coherent measurement. Results obtained by multipaction test, vibration and thermal cycle test verify the good properties of the large dimension fan beam payload array antenna. Measurements acquired by planar near field test show that the gain is 33.8 dB with radiation efficiency up to 76%, and side lobe levels of the two main planes are −19 dB and −20 dB respectively, meanwhile, the VSWR bandwidth better than 1.5 is about 400 MHz.