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Xu K.,Zhejiang University | Li H.,Zhejiang University | Zhu Z.,Science and Technology on Space Microwave Laboratory | Huangfu J.,Zhejiang University | And 2 more authors.
IEEE Transactions on Antennas and Propagation | Year: 2013

In this paper, we propose a beam forming approach capable of synthesizing versatile, pre-specified beam shapes using concentric excitations satisfying multiple weighted sinc or Bessel function distribution. We show by both theoretical calculation and full wave simulation that by tuning different weights of a sinc or Bessel function distribution, not only radiation beams with pencil, flat-topped and bimodal shapes can be synthesized, but also the beam-width and the side lobe level can be independently adjusted. An example is provided to demonstrate how an isoflux beam aiming at a better coverage of the earth surface is synthesized, and how an optimized continuous distribution is properly discretized for a physical realization of a satellite aperture array antenna. The approach proposed in this paper can be applied to a wide range of applications that require performance optimization of concentric ring array antennas. © 1963-2012 IEEE.

Zheng J.,Xidian University | Zheng J.,Science and Technology on Space Microwave Laboratory
2013 IEEE/CIC International Conference on Communications in China, ICCC 2013 | Year: 2013

In this paper, we propose to decompose the received signal into its projection on the channel vector and the corresponding perpendicular in the spatial modulation (SM) detection. Based on this decomposition, the optimal joint antenna and symbol detection can be done separately with reduced complexity and no performance loss. Moreover, the constellation symmetry and a lower bound approximation are employed in the antenna detection to reduce its complexity further. Simulation results are provided to demonstrate the performance of the proposed detectors. © 2013 IEEE.

Wang J.,Zhejiang University | Zhu Z.,Science and Technology on Space Microwave Laboratory | Li C.,Texas Tech University | Huangfu J.,Zhejiang University | Ran L.,Zhejiang University
IEEE Transactions on Circuits and Systems II: Express Briefs | Year: 2013

In this brief, we present for the first time a wireless through-the-obstacle use of a traditional potentiometer. The importance of phase-locked-loop (PLL)-based self-adaptive resonance tuning for a wireless potentiometer is emphasized. The wireless potentiometer integrates near-field communication and wireless power transfer. In order to maintain an optimal operation when severe system detuning occurs, self-adaptive resonance tuning is employed using a wideband quadrature PLL. An experimental example is demonstrated, implying a wide range of through-the-obstacle applications. © 2004-2012 IEEE.

Liu Z.,Nanjing University of Science and Technology | Chen J.,Nanjing University of Science and Technology | Chen R.,Nanjing University of Science and Technology | Chen R.,Science and Technology on Space Microwave Laboratory
Applied Computational Electromagnetics Society Journal | Year: 2011

For efficiently solving large dense complex linear systems that arise in the electric field integral equation (EFIE) formulation of electromagnetic scattering problems, a new adaptive preconditioning technique using fuzzy controller (FC) is introduced and used in the context of the generalized minimal residual iterative method (GMRES) accelerated with the multilevel fast multipole method (MLFMM). The key idea is to control the choice of the preconditioner to be used in an iterative solver by using fuzzy controller. This approach allows the expert knowledge to be taken into account on the controller design and utilizes feedback to tune the cores of the fuzzy set. Numerical results show that the best preconditioner can be selected while maintaining low cost for adaptive procedures. © 2011 ACES.

Wang Y.,Science and Technology on Space Microwave Laboratory | Fu Y.,China Academy of Space Technology
2011 International Conference on Electronics, Communications and Control, ICECC 2011 - Proceedings | Year: 2011

This paper presents a K band 3dB broadband waveguide power splitter/combiner analyzing and designing steps. In order to achieve broadband performance and at the same time to minimize the difficulty and sensitivity in the mechanical fabrication, the design uses three equal branches, simulated bandwidth is about 3.5GHz which over desirable requirement in operating frequency bands. There are good agreements between the experimental results and simulations. Measured results for this waveguide power splitter/combiner shows return loss greater than 20dB, isolation of through port and coupler port is greater than 24dB, isolation of input port and isolated port is greater than 22dB, and VSWR of each port is below 1.2. © 2011 IEEE.

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