A radar antenna system comprises a plurality of transmitting sub-arrays; a plurality of receiving sub-arrays; and a transceiving control unit coupled to the plurality of transmitting sub-arrays and the plurality of receiving sub-arrays, configured to control the plurality of transmitting sub-arrays and the plurality of receiving sub-arrays, such that the radar antenna system selectively operates in one of an amplitude-comparison mono-pulse mode and a phase-comparison mono-pulse mode.

The disclosure describes techniques to scan a radio frequency antenna beam along one or more axes. For example, for a wide transmit beam oriented such that the long axis is in azimuth, this disclosure describes techniques to scan the transmit beam in elevation, in the direction of a short axis of the transmit beam. The radar receive aperture may be synchronized with transmit beam to scan the radar receive aperture using RF beamforming such that the elevation scan of the field of view of the radar receive aperture follows the elevation scan of the transmit beam. The radar receiver circuitry may also down-convert the received radar signals to an intermediate frequency (IF). The radar receiver circuitry may digitally form monopulse receive beams at IF within the processing circuitry of the receiver electronics and digitally scan the monopulse receive beams along the long axis of the field of view.