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Publications (4)3.75 Total impact

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    ABSTRACT: The authors investigate in this study using PIN attenuator diodes to reduce the radar cross-section (RCS) of a microstrip patch antenna. A simple design guideline and a useful loading scheme are developed. In the investigation, PIN diodes are equivalent to capacitances and resistances when diodes are reverse-biased and forward-biased, respectively. According to the magnitude distribution of the induced electric field under the patch for a specific incidence angle, the loading positions of PIN diodes are selected near to where the maximum electric field appears. First, three typical incident angles are separately considered. As a result, RCS reduction for the microstrip patch antenna is realised by utilising the variable resistance characteristic (energy dissipation) of PIN attenuator diodes. Secondly, the loading positions for that three incident angles are combined to realise RCS reduction over a large angular spatial region and within a wideband frequency range, and thus an electronically controllable low RCS status can be successfully realised. The proposed design guideline is demonstrated. It is worth mentioning that, by real-time adjusting the bias status of each PIN diode, the antenna realised gain as well as the relative bandwidth is well maintained when the antenna is at work.
    IET Microwaves Antennas & Propagation 01/2012; 6(6):670-679. · 0.84 Impact Factor
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    ABSTRACT: A single-fed compact circularly-polarised (CP) microstrip antenna is designed and experimentally demonstrated. By embedding the symmetric-slit in the radiation patch and protruding a pair of perturbation elements at the boundary of the centre square slot, the proposed antenna can obtain good CP performance with effective size reduction at a fixed frequency operation. Meanwhile, an impedance transformer is utilised for impedance matching.
    Electronics Letters 01/2012; 48(4):195-196. · 1.04 Impact Factor
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    ABSTRACT: A defected ground structure (DGS) is used to suppress mutual coupling between elements in a microstrip array and eliminate the scan blindness in an infinite phased array. Two kinds of DGSs, namely back-to-back U-shaped and dumbbell-shaped DGSs, are analysed and compared. The analysis indicates that the back-to-back U-shaped DGS is better at suppressing propagation of surface waves in microstrip substrate. A two-element microstrip array with back-to-back U-shaped DGS is designed and the array characteristics against different element distances are studied. The results show that the degree of the mutual coupling suppression is increased when the element distance is reduced. However, compared with the traditional array, a higher gain and lower side lobes are obtained when a larger element spacing is selected. The scan blindness of an infinite microstrip phased array in E-plane is studied by simulation, and the calculation demonstrates that the scan blindness can be eliminated by applying a back-to-back U-shaped DGS to the infinite phased array.
    IET Microwaves Antennas & Propagation 10/2011; · 0.84 Impact Factor
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    ABSTRACT: A novel pattern reconfigurable patch antenna with a microstrip configuration is proposed. The antenna consists of a disc patch, a ring and eight radially symmetrically distributed microstrip monopoles. The patterns are reconfigured by shifting the states of the eight switches and eight reconfigurable states are available. Each conical pattern around the broadside of the antenna has a wide beam width in the azimuth plane and the eight reconfigurable patterns can cover continuously the space in the horizontal plane. The performance is very advantageous for smart antenna applications on future mobile terminals.
    Electronics Letters 01/2011; 47(21):1163-1164. · 1.04 Impact Factor