A Phased Array Perspective on the Importance of True Digital Time Delay for Wide Bandwidth Systems

With the advent of radio frequency (RF) System on Chip (SoC) and RF integrated circuit technology, mm-wave digital phased arrays can begin to offer wideband performance with digital True Time Delay (TTD). Herein we will explore challenges and benefits of using TTD vs. phase only steering and beam alignment for mm-wave phased arrays as instantaneous bandwidth desires approach 10GHz. Sidelobes and dispersion impacts will be discussed for digital phased array architectures including elemental vs subarray beamforming. Wideband digital arrays at mm-wave with high degrees of spatial segmentation have the potential to create new massive data handling challenges that drive size, weight, power, and overall cost of the processing and data network portions of the communications system.