Beamformer architectures for active phased-array radar antennas

In active phased-array antennas, the transmit and receive functions are distributed at the antenna aperture using transmit and receive (T/R) modules. The use of T/R modules provides a significant improvement in antenna performance and flexibility in the choice of array architectures. In this paper, we present a review of various beamformer architectures for active phased-array antennas. This review is limited to corporate-fed active phased-array antennas for radar applications, as the general discussion to include all phased-array types Is too broad for any one presentation. Beamformer architectures for narrow and wide bandwidth arrays, including the choice of applying an amplitude taper in the T/R module or beamformer network are discussed. Beamformer architectures that increase antenna reliability are also presented.