A flat antenna with an X band array

Design details of a flat array, high gain, low sidelobe surveillance radar antenna are described. An experimental, 512-source unit was tested at 9.6 GHz with a 1 GHz passband for rapid frequency switching. A 32 dB gain was realized with a 1 km lobe length. A 0.9 wavelength distance was established between the RF emitters and all pathways were selected by CAD studies. Printed circuits were used for the sources to reduce weight for the unit, which is a prototype of a field-erectable unit. Field test results are provided, including several performance factors which were lower than predicted.