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An aircraft reenters or flies at hypersonic speed through the atmosphere is surrounded by plasma sheath that affects on the radiation characteristics of an antenna. According to actual problems, the Navier-Stokes equations is solved using the more effective and stable AUSMPW+ scheme. The calculated electron density distribution in the sheath is concerned with the flow structure which is shown to be...
A convex optimization based beampattern synthesis method with antenna selection is proposed for linear and planar arrays. Conjugate symmetric beamforming weights are used so that the upper and non-convex lower bound constraints on the beampattern can be convex. Thus, a mainlobe of an arbitrary beamwidth and response ripple can be obtained. This method can achieve completely arbitrary sidelobe levels...
This paper presents a beam pattern synthesis method for low cost implementation of antenna arrays. Instead of designing array weights, our method synthesizes unequally-spaced array with uniform antenna weights. The effect of mutual coupling is considered when we search a set of optimum antenna positions. The determination of the antenna positions is a nonlinear optimization problem because the positions...
In this paper, a novel algorithm on beam pattern synthesis for linear aperiodic arrays with arbitrary geometrical configuration is proposed. The algorithm is based on an improved genetic algorithm (IGA) that simultaneously adjusts the weight coefficients and inter-sensor spacings of a linear aperiodic array. A novel section-based crossover and a self-supervised mutation process are developed to improve...
On-body communication channels are affected by short term fading effects. In this paper, the effect of space diversity reception for on-body communications has been investigated at a frequency of 2.45 GHz using one transmitting and two receiving narrow-band monopole antennas. An annular-slot-monopole combination (pattern diversity antenna) was also used at the receiving end. Measurements were taken...
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