Defining Phased Array Bandwidth

Phased arrays play an increasingly important role in communications and radar systems. These systems require wideband signals to achieve the desired high-performance goals. A phased array's bandwidth depends on much more than the bandwidth of its components. When designing phased arrays, the traditional time-harmonic analysis methods do not capture all of the frequency performance constraints imposed by the array architecture. Grating lobes limit the maximum element spacing, while pulse/symbol dispersion and beam squint limit maximum array size and bandwidth. Hardware frequency limits bound the operating bandwidth of the array. This article discusses time-dependent performance concerns of phased arrays that limit bandwidth, such as the constraints imposed on scan angle, frequency bandwidth, beam squint, dispersion, and hardware.