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Most reference-based image super-resolution (RefSR) methods directly leverage the raw features extracted from a pretrained VGG encoder to transfer the matched texture information from a reference image to a low-resolution image. We argue that simply operating on these raw features neglects the influence of irrelevant and redundant information and the importance of abundant high-frequency representations, leading to undesirable texture matching and transfer results. Taking the advantages of wavelet transformation, which represents the contextual and textural information of features at different scales, we propose a Wavelet-based Texture Reformation Network (WTRN) for RefSR. We first decompose the extracted texture features into low-frequency and high-frequency sub-bands and conduct feature matching on the low-frequency component. Based on the correlation map obtained from the feature matching process, we then separately swap and transfer wavelet-domain features at different stages of the network. Furthermore, a wavelet-based texture adversarial loss is proposed to make the network generate more visually plausible textures. Experiments on four benchmark datasets demonstrate that our proposed method outperforms previous RefSR methods both quantitatively and qualitatively. The source code is available at https://github.com/zskuang58/WTRN-TIP. [ABSTRACT FROM AUTHOR]

For monolithic microwave integrated circuit integration and antenna application, a novel W-band millimeter-wave transition from microstrip line to groove gap waveguide (GWG) is proposed in this communication. The transition is achieved by a modified planar triangular-microstrip patch resonator with an inner shorting via. To give a physical insight, E-field analysis is presented, and its working mechanism is similar to that of the passband filter based on coupled resonators. The proposed transition may contribute to a potential groove GWG application in the W-band radar and communication system. Finally, a back-to-back transition prototype is fabricated and assembled for measurement. To improve $S_{11}$ of the prototype, a modified CPW probe pad is applied. Moreover, the influences on $S_{11}$ and $S_{21}$ of the conductor losses are given. The measured results show that there is an excellent transition passband from 90 to 99.5 GHz, in which frequency band, $S_{11}$ is almost below −12 dB. [ABSTRACT FROM AUTHOR]

The effects of the light concentration and temperature on the performance of InGaN p-i-n homojunction solar cells were investigated experimentally. With the increase in the light concentration, the short-circuit current density Jsc increases linearly, and the open-circuit voltage Voc increases logarithmically. However, the fill factor FF and the relative efficiency \eta increase first and then decrease. On the other hand, the performance of the solar cell becomes worse with the increase in temperature. The temperature coefficients of important parameters related with the cell property were discussed. The red shift of the peak external quantum efficiencies was observed with increasing temperature due to the band-gap shrinkage. In addition, the ideality factor n and the reverse saturation current density Js were also investigated to reveal the intrinsic mechanism of temperature dependence and the effect of crystalline quality. This paper provides the variation trends of device characteristics, which are useful references concerning the reliability of GaN-based solar cells. [ABSTRACT FROM PUBLISHER]