Current Issue : July-September Volume : 2025 Issue Number : 3 Articles : 5 Articles
Running-out detection of the liquids in an infusion bag is important for medical treatment. This paper proposed a simple low-cost sensing scheme with an artificial magnetic conductor (AMC) antenna for liquid-running-out detection in infusion bags. The proposed antenna consists of a dipole antenna supported by an AMC layer. It operates in the 2.4 GHz ISM band in the without-liquid state, in the 2.0 GHz ISM band in the with-liquid state, and can be used for liquid sensing. The AMC layer isolates interference from the surrounding environment such as the standing pole. It also enhances antenna performance and improves monitoring sensitivity. This gives a peak gain of 6.45 dBi and a radiation efficiency of 98% in the without-liquid state. Meanwhile, the with-liquid state can achieve a peak gain of 4.5 dBi and a radiation efficiency of 93%. The proposed antenna is fabricated and measured, verifying its sensing performance of the liquid in the infusion bag. This antenna’s design is flexible, compact, precise, and suitable for biomedical wireless sensing....
A wideband dual-polarized dielectric resonator antenna (DRA) with gain-filtering response was proposed in this paper. First, a differentially fed, low-profile crossed-DRA was used to obtain orthogonal polarizations with two resonant modes. A radiation null at upper band edge was also generalized. Second, with the introduction of four parasitic patches at the top of the crossed DRA, another resonant mode at lower band was excited, and the bandwidth was greatly expanded. Moreover, the introduction of parasitic patches could also help improve the selectivity of realized gain with another radiation null at the upper band edge. Furthermore, four sequentially rotated shorting coupling structures (SRSCSs) were proposed for the first time to generalize two additional radiation nulls. Finally, a wideband bandpass filtering response of the realized gain with four radiation nulls was obtained. Prototypes of the proposed antennas were fabricated, and the testing results showed that the antenna had a wide operation band of 57.1% from 2.75 GHz to 4.95 GHz with sharp roll-off at the band edge. This technique could also be used in wireless communication devices at millimeter/optical front ends and other multi-wavelength fiber lasers with micro structures....
A compact and low-cost meta-radomized wearable grid array antenna (MTR-GAA) for radar sensing application at 24 GHz is presented. It is based on eco-friendly aluminumcladded Polypropylene (PP) substrate. The overall MTR-GAA size is 40 × 40 × 1.74 mm3. Prototypes are fabricated and tested, achieving consistent agreement between simulation and measurements and meeting typical requirements for the envisioned Electronic Travel Aid (ETA) radar sensing applications to aid visually impaired people. A comparison with state-of-the-art 24 GHz wearable radar antennas is also provided to endorse the advantages of the proposed metadome-antenna ensemble for the target application....
A novel deployable reflector antenna for small satellites has been designed, fabricated, and experimentally validated. The reflector utilizes a doubly curved flexible surface manufactured from a triaxially woven fabric-reinforced silicone (TWFS) composite. By leveraging high-strain composite materials, the design enables a highly compact stowed configuration while maintaining precise surface accuracy upon deployment. The deployment mechanism is proposed to accommodate a 0.6 m diameter parabolic reflector within a minimal stowed volume, optimizing space efficiency for satellite integration. To validate this concept, a prototype of the reflector antenna has been fabricated and demonstrated the feasibility and effectiveness of the proposed approach....
In this work, a frequency- and pattern-reconfigurable Yagi antenna based on liquid metal (LM) switches is proposed for pressure sensing and health monitoring. The proposed antenna consists of a dipole radiator, a reflector, a director, a dielectric substrate, and four flexible LM switches. Benefitted from the switching effect of the LM switches under external pressure, the frequency and radiation pattern of the antenna can be reconfigured. When the LM switch is fully or partially turned on, the radiation directions of the antenna are bidirectionally end-shot and end-fired, respectively. The operating frequency of the antenna can be tuned from 2.28 GHz to 2.5 GHz. It is shown that a maximum gain of 6 dBi can be obtained. A sample was fabricated and measured, and the experimental results were in good agreement with the simulations. The reconfigurable antenna can be applied in wireless pressure-sensing and health-monitoring systems....
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