12 research outputs found

    Sexing up the international

    Get PDF
    This thesis takes sexuality as its subject matter and uses a methodology informed by postcolonial studies to explore new possibilities for thinking about the international, its construction, and its contemporary politics. I argue that postcolonial readings of sexuality can impel us to rethink the meanings and politics of international theory and to challenge notions that have come to appear fixed and unchanging. The thesis canvasses how such an intervention might occur – calling especially for a focus on the local and the everyday – and considers both the utility and the limits of the contributions sexuality might make to a rethinking of international theory. My arguments are made with reference to a series of specific examples from contemporary East and Southeast Asia: the nationalistically imbued gendered and sexed figures of the national serviceman and the Singapore Girl in Singapore; the political and social repercussions of the trial of former Malaysian Deputy Prime Minister Anwar Ibrahim on charges of sodomy; newly emerging homosexual identities in Hong Kong; and the connections between sexuality and disease that inform the Thai response to HIV/AIDS. These case studies exemplify some of the ways in which sexuality can work to recast traditional scholarly understandings of the international. They also illuminate a series of aspects that shape the encounter between sexuality and the international, encompassing issues of nationalism, globalization, metaphor, spatiality and knowledge politics. Through my analysis of these issues, I argue for a broadening out of the source materials that inform knowledge about the international and the pursuit of alternative modes of reading processes of international change and exchange. I contend that scholarship of the international needs to pay more attention to instances where the borders separating everyday, national and international spaces break down, and where we might detect new forms of knowledge about the nature, politics and functioning of the international realm

    Efficient Numerical Analysis of a Periodic Structure of Multistate Unit Cells

    Get PDF
    Application of the synthetic function expansion (SFX) algorithm to the analysis of active 1- and 2D periodic structures is presented. The single unit cell consisting of a microstrip line loaded by patches positioned below the line is turned into an active structure by inserting a pair of 2 switches to the two ends of each patch; the states of the pair of switches are changed contemporaneously. Variation of the states of the switches modifies the current distribution on the structure. The tunable multistate unit cell is arranged in 24-, 120-, and 9 × 24 element configurations and numerically analyzed. The computational complexity required for the characterization of the large number of possible configurations is lightened by the use of the proposed numerical method

    Impact of mutual coupling between SKALA4.1 antennas to the spectral smoothness response

    Get PDF
    One of the advantages of arrays with aperiodic distributed elements is their ability to mitigate the detrimental mutual coupling effects on the radiation pattern. However, we show that the mutual coupling inside a random array can still generate undesired structures in the frequency response although the single antenna features a spectral smooth response. For small subsets (a couple of SKALA4.1 antennas and a 16-element array) of a low-frequency instrument station of the Square Kilometre Array, the combination of large mutual coupling and antenna geometry creates systematic distortions in the element frequency responses. This phenomenon compromises the station spectral smoothness response versus frequency. However, we demonstrate that it is possible to partially mitigate these frequency structures by reconfiguring the antenna distribution based on exclusion zones

    Mutual Coupling Analysis for a SKA1-LOW Station

    Get PDF
    The modelling of the antenna patterns represents one of the main challenges for the instrumental calibration of radio telescopes composed by antennas randomly distributed. In this work, the electromagnetic characterization of a single station of the low-frequency instrument of the Square Kilometre Array (SKA) radio telescope operating from 50 to 350 MHz is reported. The station is assumed to be composed by Log Periodic antennas. The effects of mutual coupling on the complex embedded element patterns and on the array beam are investigated by means of a full-wave electromagnetic analysis. The accuracy of a simplified, mutual coupling-free approach is presented as well

    Test-Driven Design of an Active Dual-Polarized Log-Periodic Antenna for the Square Kilometre Array

    Get PDF
    An active dual-polarized Log-Periodic antenna has been designed to meet the requirements of the low-frequency (50 - 350 MHz) radio telescope of the Square Kilometre Array (SKA). The integration of antenna and low noise amplifier has been conceived in order to achieve a high degree of testability. This aspect has been found to be crucial to obtain a smooth frequency response compatible with the SKA science cases. The design has also been driven by other factors such as the large-volume production (more than 130 000 antennas will be built) and the environmental conditions of the harsh Australian desert. A specific verification approach based on both wideband radiometric spectral and spatial measurements in relevant laboratory and in-situ conditions has been developed. Electromagnetic analyses and experimental results exhibit a very good agreement. In December 2019, this antenna was part of the reference solution for the System Critical Design Review of the SKA

    Computational electromagnetics for the SKA-Low prototype station AAVS2

    Get PDF
    We summarize the activities conducted since 2019 in the numerical electromagnetic analysis of one prototype station of the SKA-Low telescope. Working closely with the SKA Observatory, two teams based in Australia and Italy have collaborated effectively in modeling and analyzing AAVS2, which is the most recent prototype of an SKA-Low station installed in Western Australia. A comprehensive overview of the main electromagnetic parameters at element and array level obtained with two different commercial solvers is presented. Results for scattering parameters, individual element patterns, and station beams are shown; all these fully incorporate mutual coupling effects. Sensitivity of the station is addressed, as the cross-polarization performance. Finally, we also address some lessons learned and their impact on the project

    Electromagnetic modelling of the SKA-LOW AAVS1.5 prototype

    Get PDF
    The numerical modelling of the Square Kilometre Array (SKA) Aperture Array Verification System Version 1.5 is discussed. The role of this SKA prototype is placed within the perspective of the overall SKA project. The dual-polarized log-periodic SKALA4.1 antenna elements comprising a station are briefly described, along with some considerations regarding the station. Computational simulation aspects are considered, and preliminary results shown. An appraisal of the implications for station-level calibration concludes the paper

    Electromagnetic modelling of the SKA-LOW AAVS2 prototype

    Get PDF
    The computational electromagnetic modelling of a large radio telescope prototype array for the Square Kilometer Array is described. The numerical models, using the Method of Moments, are characterised by a very large number of unknowns, requiring the use of fast solution methods and high performance computing platforms. Good agreement has been obtained between results obtained on two different commercial codes. Results for both embedded element patterns and the station beam are shown. The use of the computed embedded element patterns for array calibration is briefly addressed
    corecore