Wideband, Squint-Resilient Beamforming in Ku-Band Hybrid Phased Arrays Using True-Time-Delay Architectures

Wideband electronically steered arrays used in SDR-centric systems increasingly operate with large fractional bandwidth and agile scan, where phase-only steering produces frequency-dependent pointing error (“beam squint”) that becomes a first-order constraint at Ku-band and above. This presentation motivates True-Time-Delay (TTD) beamforming as a squint-resilient architecture for wideband operation, with emphasis on hybrid phased arrays where subarray partitioning and delay placement determine achievable bandwidth–scan performance. We compare phase-based and TTD steering from a system perspective, focusing on pointing stability across frequency, scan loss, sidelobe variation with bandwidth, and the sensitivity of wideband nulling to delay quantization and channel mismatch. Architectural guidelines are derived for selecting subarray granularity and specifying TTD range/resolution based on waveform bandwidth, scan angle, and error budgets. Practical realization considerations are addressed explicitly, including insertion loss and noise-figure budgeting, group-delay linearity, channel-to-channel matching, thermal drift, and calibration strategies required to preserve coherence over bandwidth and temperature. We close with a brief discussion to connect beamforming architecture choices to software-driven beam agility, focusing on the critical hardware–software interface.