Current Issue : July-September Volume : 2025 Issue Number : 3 Articles : 5 Articles
This paper proposes a mechanically reconfigurable multi-polarization antenna based on a 3D-printed anisotropic dielectric polarizer, offering wide bandwidth, high gain, and extremely low cost. The working mechanism of the dielectric polarizer is analyzed, demonstrating its ability to efficiently convert linear polarization (LP) to circular polarization (CP) over a wide frequency range. Furthermore, the polarizer exhibits subwavelength characteristics. For a given duty cycle, its phase response depends only on the height and is independent of the aperture size. This property enables miniaturized and customized designs of the polarizer’s aperture size. Subsequently, the polarizer is placed above a Ku band waveguide and standard horn antennas. The results show that by rotating the dielectric polarizer and adjusting the positions of the antennas, right-handed CP (RHCP), left-handed CP (LHCP), and dual LP radiation switching can be achieved in the 12.4–18.0 GHz band, verifying the quad-polarization reconfigurability. Additionally, the polarizer significantly enhances the gain of the waveguide antenna by approximately 9.5 dB. Furthermore, due to the low-cost 3D printing material, the manufacturing cost of the polarizer is exceptionally low, making it suitable for applications such as anechoic chamber measurements and wireless communications. Finally, the measurement results further validate the accuracy of the simulations....
Convolutional Neural Networks (CNNs) have found widespread applications in artificial intelligence fields such as computer vision and edge computing. However, as input data dimensionality and convolutional model depth continue to increase, deploying CNNs on edge and embedded devices faces significant challenges, including high computational demands, excessive hardware resource consumption, and prolonged computation times. In contrast, the DecomposableWinograd Method (DWM), which decomposes large-size or largestride kernels into smaller kernels, provides a more efficient solution for inference acceleration in resource-constrained environments. This work proposes an approach employing the layerto- layer unified input transformation based on the DecomposableWinograd Method. This reduces computational complexity in the feature transformation unit through system-level parallel pipelining and operation reuse. Additionally, we introduce a reconfigurable, columnindexed Winograd computation unit design to minimize hardware resource consumption. We also design flexible data access patterns to support efficient computation. Finally, we propose a preprocessing shift network system that enables low-latency data access and dynamic selection of theWinograd computation unit. Experimental evaluations on VGG-16 and ResNet-18 networks demonstrate that our accelerator, deployed on the Xilinx XC7Z045 platform, achieves an average throughput of 683.26 GOPS. Compared to existing approaches, the design improves DSP efficiency (GOPS/DSPs) by 5.8×....
A novel dual-polarized 2D beam-steering antenna is proposed based on the reconfigurable double square loops (RDSLs). The antenna is composed of stacked patches with two ports and a beam-steering surface consisting of a 2 × 2 array of RDSLs. Varactor diodes are integrated on the inner square loop of the RDSL. The steerable radiation beam of the antenna can be continuously controlled by tuning four biasing voltages applied on the beam-steering surface for both polarizations. The experimental results show that the scanning ranges are up to ±32◦ for both ports in two principal planes. The proposed antenna has an average gain of 7.87 dBi with a fluctuation of less than 0.5 dB during 2D beam scanning. The cross-polarization is less than −20 dB, and the isolation between the two ports is greater than 20 dB. The proposed antenna has scannable beams for dual polarizations, stable gains, compact size, and a simple structure, which makes it a good candidate for wireless communication systems....
The intrinsic metal–insulator transition (MIT) of VO2 films near room temperature presents significant potential for reconfigurable metamaterials in the terahertz (THz) frequency range. While previous designs primarily focused on changes in electrical conductivity across the MIT, the accompanying dielectric changes due to the mesoscopic carrier confinement effect have been largely unexplored. In this study, we integrate asymmetric split-ring resonators on 35 nm epitaxial VO2 film and identify a “dielectric window” at the early stages of the MIT. This is characterized by a redshift in the resonant frequency without a significant degradation in the resonant quality. This phenomenon is attributed to an inhomogeneous phase transition in the VO2 film, which induces a purely dielectric change at the onset of the MIT, while the electrical conductivity transition occurs later, slightly above the percolation threshold. Our findings provide deeper insights into the THz properties of VO2 films and pave the way for dielectric-based, VO2 hybrid reconfigurable metamaterials....
In this paper, we design a frequency reconfigurable antenna for terahertz communication. The antenna is based on a Yagi design, with the main radiating elements being a pair of dipole antennas printed on the top and bottom of a dielectric substrate, respectively. The director and reflector elements give the antenna end-fire characteristics. The ends of the two arms of the dipole are constructed by staggered metal and graphene parasitic patches. By utilizing the effect of gate voltage on the conductivity of graphene, the equivalent length of the dipole antenna arms are altered and thereby adjust the antenna’s operating frequency. The proposed reconfigurable hybrid Yagi–Uda antenna can operate in five frequency bands separately at a peak gain of 4.53 dB. This reconfigurable antenna can meet the diverse requirements of the system without changing its structure and can reduce the size and cost while improving the performance....
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