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  • Design and Optimization of Multi-Faceted Reflectarrays for Satellite Applications | TICRA
    Physical Optics Reflectarray Reflector antenna Scattering Design and Optimization of Multi Faceted Reflectarrays for Satellite Applications Abstract The design and optimization of multi faceted reflectarrays for satellite applications are presented The objective of this work is to investigate the performance of a multi faceted reflectarray designed using a direct optimization technique To this end a single layer multi faceted reflectarray that produces a contoured beam for a European coverage in a bandwidth of 17 has been designed The performance is compared to that of a planar reflectarray as well as a shaped reflector In the considered frequency range the co polar minimum directivity within the coverage of the multi faceted reflectarray surpasses that of its planar counterpart with more than 1 dB Compared to the shaped reflector the difference between the co polar minimum directivity of the multi faceted reflectarray and the shaped reflector is only 0 3 dB To improve the cross polar radiation of the multifaceted reflectarray cross polar suppression is included in the optimization and the minimum cross polar discrimination of the optimized reflectarray is improved with 2 3 dB without any degradation of the co polar radiation Publication Proc EuCAP 2014 The 8th European Conference on

    Original URL path: http://ticra.com/papers/design-and-optimization-multi-faceted-reflectarrays-satellite-applications (2016-05-01)
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  • The Generalized Direct Optimization Technique for Printed Reflectarrays | TICRA
    algorithm The accuracy of the LP SDMoM for the design of reflectarrays with irregularly positioned and oriented array elements has been verified by comparisons with full wave method of moments Three contoured beam reflectarrays forming a high gain beam on a European coverage area have been designed a broadband design a circularly polarized design using the variable rotation technique and a design with irregularly positioned array elements The latter has

    Original URL path: http://ticra.com/papers/generalized-direct-optimization-technique-printed-reflectarrays (2016-05-01)
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  • Efficient Optimization of Large Reflectarrays Using Continuous Functions | TICRA
    which the geometry of the array elements are determined In this way the sharp transitions in the geometrical variation of the array elements can be sufficiently reproduced and gives designs that are comparable to those obtained where the array elements are directly optimized The first scheme uses complex spline representation CSR whereas the second uses Fourier series representation FSR To demonstrate the two schemes an offset 50 50 square wavelengths

    Original URL path: http://ticra.com/papers/efficient-optimization-large-reflectarrays-using-continuous-functions (2016-05-01)
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  • Direct Optimization of Printed Reflectarrays for Contoured Beam Satellite Antenna Applications | TICRA
    of Printed Reflectarrays for Contoured Beam Satellite Antenna Applications Abstract An accurate and efficient direct optimization technique for the design of contoured beam reflectarrays is presented It is based on the spectral domain method of moments assuming local periodicity and minimax optimization Contrary to the conventional phase only optimization techniques the geometrical parameters of the array elements are directly optimized to fulfill the contoured beam requirements thus maintaining a direct relation between optimization goals and optimization variables and hence resulting in more optimal designs Both co and crosspolar radiation patterns of the reflectarray can be optimized for multiple frequencies polarizations and feed illuminations Several contoured beam reflectarrays that radiate a high gain beam on a European coverage have been designed and compared to similar designs obtained using the phase only optimization technique The comparisons show that the designs obtained using the proposed direct optimization technique are superior in performance both for multi frequency and dual polarization designs A reflectarray breadboard has been manufactured and measured at the DTU ESA Spherical Near Field Antenna Test Facility to validate the proposed technique An excellent agreement of the simulated and measured patterns is obtained Available on IEEEXPLORE Publication IEEE Transactions on Antennas and

    Original URL path: http://ticra.com/papers/direct-optimization-printed-reflectarrays-contoured-beam-satellite-antenna-applications (2016-05-01)
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  • Papers tagged with : Optimization | TICRA
    modelling Graphical Processing Units GTD Measurement Method of Moments MM wave Mode matching Multilevel Fast Multipole Method Near field Optimization Physical Optics Reflectarray Reflector antenna Scattering Papers tagged with Optimization 29 Oct 2012 Design Tool for High Performance Rotationally Symmetric Reflector Antennas Authors Erik Jørgensen Peter Meincke In this paper we present an efficient higher order BoR MoM in which the unknown surface current is discretized using hierarchical Legendre basis

    Original URL path: http://ticra.com/papers/37?page=1 (2016-05-01)
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  • Shaped single-offset DBS-reception antenna for multiple satellites | TICRA
    Reflector antenna Scattering Shaped single offset DBS reception antenna for multiple satellites Abstract A direct approach to the design of a multi focal antenna system for the reception from several satellites along the orbital arc is presented The method is based on optimising the reflector shape until a desired far field performance as calculated by using Physical Optics is achieved The method is straightforward and makes use of readily available

    Original URL path: http://ticra.com/papers/shaped-single-offset-dbs-reception-antenna-multiple-satellites (2016-05-01)
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  • Papers tagged with : Physical Optics | TICRA
    Viskum A comparison of the Fast Fourier Transform FFT and direct numerical integration to solve the PO integral is presented with special emphasis on the achieved accuracy and the CPU time consumption 04 Oct 1999 Modelling of Compact Range Quiet Zone Fields by PO and GTD Authors Frank Jensen Modelling of the field in the quiet zone QZ of a compact range is a difficult task since the edges of

    Original URL path: http://ticra.com/papers/7?page=1 (2016-05-01)
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  • An Accurate and Efficient Design Tool for Large Contoured Beam Reflectarrays | TICRA
    techniques the geometrical parameters of the array elements are directly optimized to fulfil the far field requirements The design tool can be used to optimize reflectarrays based on a regular grid as well as an irregular grid Both co and cross polar radiation can be optimized for multiple frequencies polarizations and feed illuminations Two offset contoured beam reflectarrays that radiate a high gain beam on an European coverage have been

    Original URL path: http://ticra.com/papers/accurate-and-efficient-design-tool-large-contoured-beam-reflectarrays (2016-05-01)
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