Newly Developed Co-Feed Type SSR Antenna

The new type Secondary Surveillance Radar (SSR) antenna which has use Air Route Surveillance Radar (ARSR) reflector has been developed. The typical SSR uses a relatively small antenna on the top of the radar reflectors. The small vertical dimension of the antenna produces a very wide elevation beamwidth which does not discriminate against interrogation or replies reflected from the ground or sea. This problem can be overcome by utilizing the ARSR reflector for the SSR, that is, the particular dual horn arrangement is used and the appropriate combination of the two outputs of the dual offset feeds can be compensate for the elevation offset angle and coincide the beam noses of the ARSR and the SSR pattern. This particular feed design also provides excellent horizontal SSR pattern which is optimum for monopulse tracking. The SSR antenna is effectively used as a senser of Discrete Address Beacon System (DABS).