Phased Array Systems – Design Considerations & System Demonstration

This paper discusses the design, verification, and calibration of phased array platforms at a high level. The phased array architectures (analog, digital, hybrid) and their trade-offs are discussed. Antenna selection and design options are considered based on application requirements. Measurement-based cascade models of the mixed-signal channels are described to obtain system figures of merit as a function of scan angles and amplitude tapers. Limitations imposed by quantization and root-mean square errors can be modelled using these cascades. Beam weight synthesis and array thinning are shown to achieve desired beam masks, contours, and power consumption specifications for arbitrary arrays with measured, modeled, or ideal embedded element patterns. Finally, a basic calibration routine for a hybrid phased array architecture is described, and the simulated and measured performance is compared. The application requirements of a phased array system drive antenna selection, aperture size, lattice shape, power consumption, calibration capability, and the number of simultaneous beams available.