Reconfigurable contour beam reflector antennas using adjustable subreflector and adjustable single feed

Theunissen, Wilhelmus H.; Yoon, Hwan‐Sik; Washington, Gregory; Burnside, W. D.

doi:10.1002/(sici)1098-2760(19990620)21:6<436::aid-mop12>3.3.co;2-n

Cited by 2 publications

(7 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Fig. 1 shows a Cassegrain dualoffset reflector antenna system where the surface shape of the main reflector is described by the function [11] (1)…”

Section: A Antenna System Descriptionmentioning

confidence: 99%

“…If the total number of actuators and their deflections were infinite, then any contoured surface to any degree of accuracy can be found. If one were to limit the number of actuators and their displacements the actuator positions representing the "best fit" can be found [11], [20]. More actuators can be added if more resolution is needed and actuators can be removed if redundancies are not needed.…”

Section: Software and Sensing Systemmentioning

confidence: 99%

“…The surface shape of the main reflector is obtained using diffraction synthesis to produce contiguous United States (CONUS) beam for an undeformed, initial subreflector shape [8], [11]. The subreflector surface is then calculated for the preshaped and fixed main reflector shape such that it generates different geographical shapes.…”

Section: Software and Sensing Systemmentioning

confidence: 99%

“…The far field is calculated following [11]. The vector potential and the scattered fields from the main reflector are given by Using the far-field approximation , the calculation of the required field quantities can be achieved as…”

Section: Software and Sensing Systemmentioning

confidence: 99%

“…where (11) When optimizing the actuation value of each actuator, the far field for the calculated subreflector shape needs to be evaluated many times over the -space of the antenna footprint. This requires a very efficient far-field evaluation algorithm.…”

Section: Software and Sensing Systemmentioning

confidence: 99%

See 4 more Smart Citations

Design, modeling, and optimization of mechanically reconfigurable aperture antennas

Washington¹,

Yoon²,

Angelino³

et al. 2002

IEEE Trans. Antennas Propagat.

View full text Add to dashboard Cite

The work in this study develops the framework for placement and actuation of novel reconfigurable dual-offset contour beam reflector antennas (DCBRA). Toward that end, the methodology for the antennas' design is defined. In addition, two separate optimization problems are stated and solved: actuator position optimization and actuation value optimization. For the former, a method termed as greatest error suppression method is proposed where the position of each actuator is decided one by one after each evaluation of the error between the desired subreflector shape and the actual subreflector shape. For the second problem, a mathematical analysis shows that there exists only one optimal configuration. Two optimization techniques are used for the second problem: the simulated annealing algorithm and a simple univariate optimization technique. The univariate technique always generates the same optimal configuration for different initial configurations and it gives the low bound in the evaluation of the error. The simulated annealing algorithm is a stochastic technique used to search for global optimum point. Finally, as an example the results of the proposed optimization techniques are presented for the generation of a subreflector shape corresponding to the geographical outline of Brazil.Index Terms-Active antennas, piezoelectric devices, reconfigurable antennas.

show abstract

“…Fig. 1 shows a Cassegrain dualoffset reflector antenna system where the surface shape of the main reflector is described by the function [11] (1)…”

Section: A Antenna System Descriptionmentioning

confidence: 99%

Section: Software and Sensing Systemmentioning

confidence: 99%

Section: Software and Sensing Systemmentioning

confidence: 99%

Section: Software and Sensing Systemmentioning

confidence: 99%

Section: Software and Sensing Systemmentioning

confidence: 99%

See 3 more Smart Citations

Design, modeling, and optimization of mechanically reconfigurable aperture antennas

Washington¹,

Yoon²,

Angelino³

et al. 2002

IEEE Trans. Antennas Propagat.

View full text Add to dashboard Cite

show abstract

Efficient Shape Control of Distributed Reflectors with Discrete Piezoelectric Actuators

Andoh

Washington

Yoon

et al. 2004

Journal of Intelligent Material Systems and Structures

View full text Add to dashboard Cite

In the current article, a novel approach to the shape control problem with a limited number of discrete actuators is presented. In optimizing the actuator locations, first the reference input was expanded with a representative set of eigenfunctions. From the expansion coefficients, the dominant modes in the reference input were identified. Next the distributed parameter system was rewritten in modal coordinates and the irrelevant modes were truncated. Finally, the actuator locations were selected such that the singular values of the controllability matrix of the truncated system were maximized. The steady state actuation forces were optimized such that a cost function based on the absolute value of the steady state error is minimized. To improve the transient response, a hybrid of dynamic modal control algorithm and the optimization method is developed. Four discrete linear actuators for the one-dimensionally curved reflector and eight actuators for the two-dimensionally curved reflector are utilized. The structures are controlled and assessments for experimental implementation are made.

show abstract

Reconfigurable contour beam reflector antennas using adjustable subreflector and adjustable single feed

Cited by 2 publications

References 0 publications

Design, modeling, and optimization of mechanically reconfigurable aperture antennas

Design, modeling, and optimization of mechanically reconfigurable aperture antennas

Efficient Shape Control of Distributed Reflectors with Discrete Piezoelectric Actuators

Contact Info

Product

Resources

About