23 research outputs found

    A Novel Single-Source Surface Integral Method to Compute Scattering from Dielectric Objects

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    Using the traditional surface integral methods, the computation of scattering from a dielectric object requires two equivalent current densities on the boundary of the dielectric. In this paper, we present an approach that requires only a single current density. Our method is based on a surface admittance operator and is applicable to dielectric bodies of arbitrary shape. The formulation results in four times lower memory consumption and up to eight times lower time to solve the linear system than the traditional PMCHWT formulation. Numerical results demonstrate that the proposed technique is as accurate as the PMCHWT formulation.Comment: Submitted to IEEE Antennas and Wireless Propagation Letters on November 18, 201

    Modulator structures for radio-on-fiber applications, Journal of Telecommunications and Information Technology, 2003, nr 1

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    Traditional electro-optic modulators are not optimized for bandpass applications such as radio-on-fiber delivery systems due to their limited electro-optic response. This paper presents a resonant electrode structure that can be employed in optical modulator designs to enhance the electro-optic response of the modulator over a narrow frequency band, and improve the performance of optical radio systems. A simple model of the structure is developed, and experimental results validating the model and illustrating the effectiveness of the structure are presented

    Study of bifocal dual reflectarray configurations for multi-beam antennas in ka-band

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    This paper describes the design of multi-beam dual reflectarray antennas for operation in the Ka-band satellite transmission band (around 20 GHz), using the bifocal design concept to improve antenna performance. This technique has been first applied to obtain beam compression with adjacent feeds, resulting in low radiation efficiency. Then it has been used without beam compression to correct beam aberration, showing better results than an equivalent single-focus reference reflector. The simulated radiation patterns in the elevation plane and the amplitude distributions of the incident field on each reflectarray have been calculated for different antenna configurations
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