The Experts below are selected from a list of 3558 Experts worldwide ranked by ideXlab platform

Yong Jin Zhou - One of the best experts on this subject based on the ideXlab platform.

  • Wideband Low Frequency Antenna with Folded Feed L-slot Cut Patch
    2019 International Conference on Microwave and Millimeter Wave Technology (ICMMT), 2019
    Co-Authors: Lu Xu, Yong Jin Zhou
    Abstract:

    A wideband low Frequency Antenna fed by a folded structure is presented in this paper. The folded configuration and L-shaped slot are introduced for broadening the impedance bandwidth of the Antenna. The length of the patch is $0.27 \lambda$ , where $\lambda$ is the free-space wavelength at the center Frequency of its operating band. Results show that an impedance bandwidth of 108.8% for $VSWR \leqslant 2$ from 0.67 to 2.27 GHz was achieved. Other than the wideband low Frequency characteristic, the presented Antenna also has high gain through this band. Owing to its wideband low Frequency characteristics, it is highly suitable for applications in many wireless communication systems.

  • Ultra-wideband Low Frequency Antenna for Cellular Communication in High-speed Rail Scenario
    2019 Photonics & Electromagnetics Research Symposium - Fall (PIERS - Fall), 2019
    Co-Authors: Jiangtao Xu, Jinggang Yang, Zhaohui Zhang, Yong Jin Zhou
    Abstract:

    In recent years, more and more people choose to travel by high-speed rail. As a result, the 2G/3G/4G/5G network under high-speed rail scenario needs to have good coverage band and high gain. In this paper, an ultra-wideband low-Frequency high-gain monopole Antenna is proposed. By using the meander technology and introducing the tapered structure, the proposed Antenna operates over a bandwidth of 645-752 MHz and 1010-6000 MHz (VSWR

Yi Zhang - One of the best experts on this subject based on the ideXlab platform.

  • Design and transmission line model analysis of a compact dual-Frequency Antenna
    Iet Microwaves Antennas & Propagation, 2012
    Co-Authors: G. Wu, Li Li, Yanfeng Geng, Yi Zhang, Wenmei Zhang
    Abstract:

    In this study, a compact dual-Frequency Antenna with stacked configuration is proposed, and the transmission line model for the Antenna is also studied. Compared with the conventional stacked dual-Frequency Antenna, the radiating element with half-guided wavelength at the first resonant Frequency is arranged on two layers connected through one via hole, thus the dimension of the Antenna can be reduced effectively. Each patch of the Antenna is modelled as a section of transmission line terminated by two radiating slots, and a via hole between stacked patches is represented by an inductor and a capacitor in parallel. In particular, the formula for the capacitor of a via hole between stacked patches is provided when the Antenna is fed from the upper patch. To validate the transmission line model, two compact dual-Frequency Antennas are designed and fabricated. The results of simulations and measurements indicate that the proposed transmission line model is suitable for analysing compact dual-Frequency Antennas with stacked configuration.

  • novel model for propagation loss prediction in tunnels
    IEEE Transactions on Vehicular Technology, 2003
    Co-Authors: Yi Zhang
    Abstract:

    Radio signal propagation in a tunnel exhibits distinct near and far regions with quite different propagation characteristics. This paper proposes a model that can distinguish these propagation regions and predict their respective propagation losses in the tunnel. The model relies on a break point to separate the propagation regions and a hybrid technique to calculate the propagation losses. The location of the break point is determined with the solution of a novel tunnel-propagation equation for the first time. The solution shows that the location of the break point depends strongly upon Frequency, Antenna position, and tunnel transversal dimensions. The model is compared with data measured in various tunnels at different frequencies (900 MHz, 1.8 GHz, and 2.448 GHz). The results show reasonable agreement between predictions and measurements.

Gert Frølund Pedersen - One of the best experts on this subject based on the ideXlab platform.

  • Integrated Millimeter-Wave Wideband End-Fire 5G Beam Steerable Array and Low-Frequency 4G LTE Antenna in Mobile Terminals
    IEEE Transactions on Vehicular Technology, 2019
    Co-Authors: Mohammad Mehdi Samadi Taheri, Abdolali Abdipour, Shuai Zhang, Gert Frølund Pedersen
    Abstract:

    In this paper, a novel technique of collocating a millimeter-wave end-fire 5G beam steerable array Antenna with a low-Frequency planar inverted-F Antenna (PIFA) is presented. In this technique, the low-Frequency Antenna can be transparent by using some grating strips between the low- and high-Frequency Antennas. A quad-element mm-wave array with end-fire radiation patterns operating in 22-31 GHz is integrated with a dual-band low-Frequency PIFA in a mobile terminal. The novelty of this paper is the collocation of a high-Frequency end-fire 5G Antenna array with an old-generation low-Frequency Antenna, such as 4G in small space in the mobile terminal, without interfering with the radiation pattern and impedance matching of both low- and high-Frequency Antennas. The proposed 5G Antenna covers 22-31 GHz and can scan ±50° with the scan loss of better than 3 dB. The coverage efficiency of the proposed mm-wave 5G Antenna is better than 50% and 80% for a minimum gain of 4 and 0 dBi in 22-31 GHz, respectively. The gain of the high-Frequency Antenna array is better than 9.5 dBi at 28 GHz. The low-Frequency Antenna covers some practical 4G LTE bands from 740-960 MHz and 1.7-2.2 GHz bands. The measured results in both low and high frequencies agree well with the simulations.

Kwok Wa Leung - One of the best experts on this subject based on the ideXlab platform.

  • Wideband Dual-Frequency Antenna With Large Frequency Ratio
    IEEE Transactions on Antennas and Propagation, 2019
    Co-Authors: Li Ying Feng, Kwok Wa Leung
    Abstract:

    This communication investigates a new type of compact dual-Frequency Antenna, which is realized by using a single rectangular dielectric block with a groove along its center. It integrates a microwave dielectric resonator Antenna (DRA) with a millimeter-wave Fabry–Perot resonator Antenna (FPRA). The DRA is fabricated out of a dielectric block, excited by a vertical conducting strip on its side wall. The FPRA is realized by sticking the adhesive copper tape on the surfaces of the groove, forming a pair of parallel plates and the ground plane. The FPRA is excited by a sleeve-integrated L-probe, which suppresses the cross-polar fields and widens the bandwidth of the FPRA. To validate the idea, a dual-Frequency Antenna, covering both the 2.4 and 24 GHz ISM bands, was designed and measured. The DRA operates in its TEx111 mode, whereas the FPRA operates in its fundamental mode. Next, a wideband dual-Frequency Antenna was designed to further cover the 4G and future 5G Frequency bands. Both of the TEx111 and TEx113 modes of the DRA are excited, broadening the bandwidth in the microwave band. Also, the FPRA mode and two L-probe modes are simultaneously excited to increase the bandwidth in the millimeter-waveband. The S-parameters, radiation patterns, Antenna gains, and Antenna efficiencies of the dual-Frequency Antennas are studied in detail. Reasonable agreement between the measured and simulated results is observed.

  • Compact dual-Frequency Antenna for 2.4/60 GHz applications
    2017 10th Global Symposium on Millimeter-Waves, 2017
    Co-Authors: Kwok Wa Leung
    Abstract:

    A compact dual-Frequency Antenna with two-port excitation and large Frequency ratio is presented. It consists of a circularly-polarized (CP) microstrip patch Antenna at 2.4 GHz and a linearly-polarized (LP) substrate-integrated cylindrical dielectric resonator Antenna (DRA) at 60 GHz, resulting in a large Frequency ratio of as high as 25. The two Antenna parts are designed on a single substrate, giving a very compact structure. Slot-coupled source and probes are used to excite the upper-band DRA and the lower-band patch Antenna, respectively. ANSYS HFSS was used to simulate the S-parameters, radiation patterns, Antenna gains, and axial ratio (AR) (patch Antenna part only) of the two Antenna parts. The lower-band patch Antenna has an impedance bandwidth of 17.3% and AR bandwidth of 15.3%, whereas the upper-band has an impedance bandwidth of 13.15%.

  • Substrate-Integrated Two-Port Dual-Frequency Antenna
    IEEE Transactions on Antennas and Propagation, 2016
    Co-Authors: Kwok Wa Leung
    Abstract:

    A two-port dual-Frequency substrate-integrated Antenna with a large Frequency difference is presented. It consists of a differentially fed slot Antenna and a substrate-integrated dielectric resonator Antenna for low- and high-Frequency radiation, respectively. The former is loaded by a hollow patch, whereas the latter is fabricated inside the hollow region of the patch by using air holes and metalized vias. Beneath the Antenna substrate is a second substrate on which slot-coupled sources are printed to feed the two Antennas. For demonstration, a two-port dual-Frequency Antenna working at 5.2-GHz WLAN band and 24-GHz ISM band was designed, fabricated, and measured. The S-parameters, radiation patterns, and Antenna gains of the two Antenna parts are reported. Reasonable agreement between the measured and simulated results is observed. Very good isolation of over 35 dB between the two Antenna parts is observed.

Richard P. Kendall - One of the best experts on this subject based on the ideXlab platform.

  • CREATE: Software Engineering Applications for the Design and Analysis of Air Vehicles, Naval Vessels, and Radio Frequency Antennas
    Computing in Science & Engineering, 2016
    Co-Authors: Douglass E. Post, Chris A. Atwood, Kevin P. Newmeyer, Robert L. Meakin, Richard L. Vogelsong, Miles M. Hurwitz, Saikat Dey, John N. D'angelo, Nathan S. Hariharan, Richard P. Kendall
    Abstract:

    Today, rapid product innovation is essential to remain competitive. To help spur innovation in the acquisition of major defense systems and reduce their cost, time, and risks, the US Department of Defense launched the Computational Research and Engineering Acquisition Tools and Environments (CREATE) program in 2006 to develop and deploy physics-based, high-performance computing software applications for the design and analysis of military aircraft, ships, and radio Frequency Antenna systems (and more recently, ground vehicles) through the construction and analysis of virtual prototypes. Code development began in 2008, and eight years later, CREATE is already beginning to accomplish these goals.

  • The CREATE Program Software Applications for the Design and Analysis of Air Vehicles, Naval Vessels, Radio Frequency Antennas, and Ground Vehicles
    2015
    Co-Authors: Douglass E. Post, Chris A. Atwood, Kevin P. Newmeyer, Robert L. Meakin, Richard L. Vogelsong, Miles M. Hurwitz, John N. D'angelo, Nathan S. Hariharan, Richard P. Kendall
    Abstract:

    Abstract : To help spur innovation in the acquisition of major defense systems and reduce their cost, time and risks, the Department of Defense launched the Computational Research and Engineering Acquisition Tools and Environments (CREATE) Program in 2006. The CREATE goal is to develop and deploy physics-based high performance computing software applications for the design and analysis of military aircraft, ships, and radio Frequency Antenna systems (and more recently ground vehicles) through the construction and analysis of virtual prototypes for those systems. Code development began in 2008, and now CREATE is already beginning to accomplish these goals.