Planar C-band antenna with digital beamforming

Smart antennas with adaptive beamforming and beamsteering are required to enhance the overall system performance of future communication and navigation systems. The generation of multiple beams, side lobe attenuation and definite nulling are important features to reduce interference and to facilitate high-quality communication channels or to improve the accuracy of navigation data. This paper describes the design and fabrication of a compact C-band antenna with digital beamforming (DBF) as a breadboard model. It uses a 5/spl times/5 array of slot-coupled microstrip patches with RHCP that form a multilayer structure together with the networks for calibration and IQ distribution. The complete antenna was tested with different parameter settings and the measurement results demonstrate its excellent and versatile characteristics.