Digital beamforming and adaptive techniques

With recent developments, the array designer now has the option of placing active elements at the array face for both transmit and receive functions, and to perform digitally programmable operations on the signals at each element. The spatial filtering functions required of the array; and the techniques and architectures which are available for their realisation are examined. Attention is focussed on the receiving function of the array, since this is generally more demanding in terms of the number of beams to be generated and their sidelobe performance than the transmit function.