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oe1(光电查) - 科学论文

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  • [IEEE 2018 IEEE Conference on Antenna Measurements & Applications (CAMA) - Va?ster?s (2018.9.3-2018.9.6)] 2018 IEEE Conference on Antenna Measurements & Applications (CAMA) - Train Communication System with Distributed Antenna System using Optical Frequency Doubler in 90 GHz Band

    摘要： A MilliMeter Wave (MMW) backhaul technology for advanced high-speed trains running a tunnel for a long distance is under development for the communication gathering a large number of passenger communications transmitting to the ground. The authors are studying a system that realizes large capacity communication between trains and the ground by arranging Distributed Antenna System (DAS) along with a long distance railway. In order to transmit a radio signal between distant antennas and the main frame of base station physically, it is necessary to avoid the influence of fiber dispersion for Radio over Fiber (RoF) which transmits a radio signal over the light. We are investigating RoF system with optical multiplication which can obtain doubled frequency after transmission. In this paper, we develop the vector modulation signal transmission by the RoF used for the downlink of the base station and report on the result of the packet communication experiment with the base station and the terminal.

    关键词： DAS,RoF,millimeter wave,Frequency multiplication

    更新于2025-11-28 14:23:57

  • [IEEE 2018 12th International Congress on Artificial Materials for Novel Wave Phenomena (Metamaterials) - Espoo, Finland (2018.8.27-2018.9.1)] 2018 12th International Congress on Artificial Materials for Novel Wave Phenomena (Metamaterials) - Self-complementary tessellations as universal design approach for LP-to-CP transforming frequency selective surfaces

    摘要： Recently self-complementary frequency-selective surfaces (FSSs) have been shown capable of linear-to-circular polarization transformation. In this work we numerically and experimentally prove generality of this approach showing that similar self-complementary tessellations can be used as FSS patterns in both the microwave and the sub-millimeter wave ranges. Moreover, we simulated two Escher’s tessellations as patterns of microwave FSSs to further demonstrate the polarization transform function of arbitrary self-complementary FSSs.

    关键词： linear-to-circular polarization transformation,self-complementary tessellations,microwave,sub-millimeter wave,frequency-selective surfaces

    更新于2025-09-10 09:29:36

  • High-Periphery GaN HEMT Modeling up to 65 GHz and 200°C

    摘要： In this article, we report on the temperature-dependent GaN HEMT behavior. To evaluate the potentialities of this kind of active solid-state electronic device at its best, the experiments are performed at extreme operating conditions. As a case study, we consider a large 0.25-μm GaN HEMT with a gate periphery of 1.5 mm, providing a high dissipated power of 5.1 W. The tested semiconductor device is characterized by measuring scattering parameters at high frequencies up to 65 GHz and at high ambient temperature up to 200°C. To assess the impact of the thermal effects on high-frequency GaN HEMT performance, an equivalent circuit is analytically extracted and then used to determine the main RF figures of merit. The achieved experimental results show evidence that the increase of the temperature causes a significant degradation in device performance.

    关键词： scattering parameter measurements,high-power,GaN HEMT,high-temperature,Active solid-state electronic device,millimeter-wave frequency

    更新于2025-09-10 09:29:36