Theoretical Studies of Sub-THz Active Split-Ring Resonators for Near-Field Imaging
For researchers in sub-THz imaging, this work offers a theoretical foundation for ASRR-based imagers, but it is incremental as it builds on existing SRR concepts.
This paper develops a theoretical framework for Active Split-Ring Resonators (ASRRs) for near-field imaging, providing design guidelines to optimize SNR and power consumption for scalable arrays.
This paper develops a theoretical framework for the design of Active Split-Ring Resonators (ASRRs). An ASRR is a Split-Ring Resonator (SRR) equipped with a tunable negative resistor, enabling both switchability and quality factor boosting and tuning. These properties make ASRRs well-suited for integration into dense arrays on silicon chips, where pixelated near-fields are generated and leveraged for high-resolution 2D imaging of samples. Such imagers pave the way for real-time, non-invasive, and low-cost imaging of human body tissue. The paper investigates ASRR coupling to host transmission lines, nonlinear effects, signal flow, and the influence of various noise sources on detection performance. Verified through simulations, these studies provide design guidelines for optimizing the Signal-to-Noise Ratio (SNR) and power consumption of a single pixel, while adhering to the constraints of a scalable array.