Phase shifter control

A scanning system for a phased array antenna for operation at a selected frequency between a first frequency and a second frequency includes the storage (50) of phase shift command signals for each of the phase shifters (24) coupled to radiating elements of the antenna. The memory (34) which stores the phase shift commands is addressed sequentially to provide for a step-wise scanning of a beam of radiant energy at a first frequency of the antenna. The addressing (46) is accomplished by incrementing a count resulting from a counting of clock pulses (40). Compensation for the stepped positions of the beam for the difference between the selected frequency and the first frequency is accomplished by altering the number of pulses (54) which increment the count of the addressing. The altering is accomplished by the storing (50) of sequences of clock pulses at varying temporal spacings which are used for gating (44) out selected ones of the incrementing pulses.