A broadband phased frequency antenna array uses frequency steering with phase-shift stabilization. Phased frequency steering allows wider intermediate bandwidth than available from frequency steered arrays, with fewer phase shifters than required by phase steered arrays. For a given instantaneous bandwidth (such as for FM-chirp or frequency agility operations), the phased frequency steered array provides a straightforward trade-off between sidelobe level and the number of phase shifters. The antenna includes a linear array (10) of phase-shift/time- delay modules (FIG. 1b), each including (a) a phase-shift element (PSE) with a phase shifter (PS), and (b) a number of time-delay elements (TDE) coupled through respective time-delay feeds (TDF) to the phase shifter. In accordance with conventional antenna pattern weighting, the phase shifters are concentrated in the center of the array (10), with the number of time-delay elements in a phase-shift/time-delay module increasing for modules located toward the edge of the array, producing the desired phase shifter "thinning". The phase shifter of each phase- shift/time-delay module is cooperatively set relative to a scan frequency to provide an appropriate phase-shift offset that aligns the phase front segments (S.sub.0 -S.sub.13), achieving a continuous phase slope across the phase front (FIG. 1c).
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