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This paper presents the development and characterization of a miniaturized RF sensor designed for temperature sensing applications, leveraging advanced additive manufacturing techniques. The sensor utilizes NiTiNOL, a superelastic alloy, as the temperature-sensing material, integrated into a split-box resonator structure. The resonator operates at a frequency of 38.125 GHz, and the design benefits from the flexibility and precision offered by 3D printing technology. This approach allows for a compact form factor and robust performance in harsh environments. The sensor's performance was evaluated through a series of simulations, demonstrating high sensitivity and reliability in temperature measurement. The results highlight the potential of additively manufactured RF sensors in various industrial, medical, and environmental monitoring applications, offering advantages such as reduced size, weight, and power consumption, along with enhanced mechanical robustness and thermal stability. This work underscores the significance of additive manufacturing in advancing next-generation sensor technologies.
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Broadside‐Coupled Split Ring Resonators as a Model Construct for Passive Wireless Sensing
Abstract Passive and wireless Radio‐Frequency (RF) sensors are a unique, enabling modality for emerging applications in environmental sensing. These sensors exhibit several key features that may unlock new functionalities in complex environments: sensors are composed of zero electronic components, are wirelessly interrogated even in opaque media, and structures are often inherently biocompatible. Such capabilities make it unique in the realm of sensing architectures. Here, the broadside‐coupled, split‐ring resonator is studied as a compact and versatile model structure for RF sensing (of potentially mechanical and biochemical environments). A new analytical model is derived to assess resonator behavior—these yield a rapid, first‐order approximation of the resonator resonant frequency or sensitivity. Finally, experimental investigations into how sensors may be optimally designed, sized, and interrogated to enhance sensitivity or spectral intensity are performed. These studies encompass a wide variety of potential dimensional and dielectric modifications that may be relevant to emerging sensors. Last, hydrogel polymeric sensors are synthesized and studied to assess how practical sensors may deviate in response from expectations. Such investigations lay the groundwork for how such sensing architectures may be adapted to fit application needs.
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- Award ID(s):
- 1942364
- PAR ID:
- 10406786
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Sensor Research
- Volume:
- 2
- Issue:
- 10
- ISSN:
- 2751-1219
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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