- 标题
- 摘要
- 关键词
- 实验方案
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Experimental Evaluation of Multipath Mitigation in TDOA-Based Indoor Passive Localization System Using A Beam Steering Broadband Circular Polarization Antenna
摘要： An experimental evaluation of multipath mitigation using a beam steering broadband circular polarization antenna (BSBCPA) in indoor passive localization system based on time differences of arrival (TDOA) is presented in this paper. The BSBCPA consists of a beam switch network, four identical hexagon patch elements and their respective feeding networks. By controlling the states of a radio frequency (RF) switch in the beam switch network, four steering circular polarization beams can be excited separately for azimuth omnidirectional coverage. Combining the spatial selectivity of steering beams and circular polarization in the BSBCPA, the positioning inaccuracy from indoor multipath propagation can be mitigated. In two different indoor environments with line of sight (LOS), complex multipath, when transmitting a 20 MHz bandwidth signal in WLAN, the 2D positioning mean error obtained is 0.7 m and 0.82 m, respectively. Compared with conventional omnidirectional linear polarization antenna (OLPA), the BSBCPA can at least improve positioning accuracy by 51%. The experimental results show that the proposed BSBCPA can significantly mitigate multipath propagation for TDOA-based indoor passive localization.
关键词： multipath mitigation,beam steering antenna,indoor passive localization,circular polarization,TDOA
更新于2025-09-23 15:22:29
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Beam Steering of a Terahertz Semi Bow Tie Antenna Using Parasitic Graphene Ribbons
摘要： In this paper, a reconfigurable beam-scanning planar antenna is proposed in terahertz frequencies. The presented structure consists of a semi bow tie antenna surrounded by circularly arranged parasitic pieces of graphene. The performance of the proposed antenna is investigated considering three different states where a PEC ground plane and a graphene ground layer with chemical potentials 0 (mode A) and 1 (mode B) are utilized at the bottom of the substrate. The proposed antenna is designed for utilization at a specific frequency of 1.2 THz in all these three states. The achieved antenna boresight and radiation pattern are altered through changing the conductivity of parasitic graphene elements and ground plane, which is obtained by controlling the corresponding chemical potential of the graphene segments. In addition, the parasitic graphene elements, located around the antenna, provide a high degree of freedom for altering the radiation pattern and antenna boresight. The parasitic elements operate as directors in modes A and B, whereas they act as reflectors in PEC ground state. Moreover, a high beam steering capability is obtained as chemical potentials of graphene elements are allocated between 0 and 1, whereas a PEC ground layer is employed at the bottom of the antenna. It should be noted that the gain and front-to-back ratio of the antenna are controlled using different chemical potentials of the graphene elements. A wide range of scan angles allocated between 0 and 180°, and toward the left and right directions in constant φ plane is achieved for the designed antenna.
关键词： Terahertz,Graphene,Reconfigurable,Beam steering,Antenna
更新于2025-09-23 15:21:01
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[IEEE 2018 IEEE International Symposium on Antennas and Propagation & USNC/URSI National Radio Science Meeting - Boston, MA, USA (2018.7.8-2018.7.13)] 2018 IEEE International Symposium on Antennas and Propagation & USNC/URSI National Radio Science Meeting - A Circularly Polarized Triple-Feed Multi-Beam Array Antenna Using Planar Magic- Ts
摘要： A circularly polarized triple-feed multi-beam array antenna employing two types of planar magic-Ts is proposed. The proposed array antenna, where each of the antenna elements are circularly polarized antennas provides three different radiation patterns in the x-z and y-z planes. The performance of the proposed antenna is experimentally evaluated. The 10-dB impedance bandwidth of the antenna is better than 3.1% and 3-dB axial ratio bandwidth is 0.81%. All these features make the proposed antenna very suitable for direction-of-arrival estimation antennas, beam steering antennas and wide-angle rectennas.
关键词： magic-T,wide-angle rectenna,direction-of-arrival estimation antenna,triple-feed,beam steering antenna
更新于2025-09-19 17:15:36
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[IEEE 2018 International Conference on Electromagnetics in Advanced Applications (ICEAA) - Cartagena des Indias, Colombia (2018.9.10-2018.9.14)] 2018 International Conference on Electromagnetics in Advanced Applications (ICEAA) - A Low-Profile, Planar, Power-Efficient 2D Beam-Steering Antenna Technology
摘要： The paper explains a recently demonstrated 2D beam-steering antenna technology and its potential to develop a low-cost communication-on-the-move (COTM) terminal antenna. A low-cost COTM antenna is critical for receiving TV and internet via existing geostationary and upcoming low-earth-orbit (LEO) satellite constellations. The new beam-steering technology is based on near-field phase transformation and its working is verified by a prototype design reported recently. Performance indicators of the prototype are compared here with some commercially available COTM terminal antennas. A fully passive design, low-profile, low power requirements, and simple design configuration give the new steering antenna a competitive advantage over existing COTM terminal antennas from KYMETA and ThinKom.
关键词： low-earth-orbit (LEO) satellite,communication-on-the-move (COTM),low-profile,beam-steering antenna,near-field phase transformation
更新于2025-09-10 09:29:36
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[Institution of Engineering and Technology 12th European Conference on Antennas and Propagation (EuCAP 2018) - London, UK (9-13 April 2018)] 12th European Conference on Antennas and Propagation (EuCAP 2018) - Mechanical Beam Steering Circular Patch Antenna
摘要： This work reports preliminary results and a prototype of an innovative mechanical beam steering circular patch antenna for 5G indoor cellular access networks with sub-6 GHz operation. The beam steering is achieved using 18 screws installed around the circular patch radiator, working as a reflector by proper managing the screws position and height. The new antenna can steer its main beam over 360o in azimuth plane and from -30o to 30o in the elevation plane with gain up to 8.01 dBi at 4.6 GHz.
关键词： beam steering,Antenna,mechanical reconfiguration,circular patch
更新于2025-09-04 15:30:14