All Outputs (19)

Slepian eigenvalues as tunnelling rates (2022)
Journal Article
Creagh, S. C., & Gradoni, G. (2023). Slepian eigenvalues as tunnelling rates. Annals of Physics, 449, Article 169204. https://doi.org/10.1016/j.aop.2022.169204

We calculate the eigenvalues of an integral operator associated with Prolate Spheroidal Wave Functions (or Slepian functions) by interpreting them as tunnelling probabilities in an analogous quantum problem. Doing so allows us to extend a well-known... Read More about Slepian eigenvalues as tunnelling rates.

Acoustic radiation from random waves on plates (2022)
Journal Article
Mohammed, N. M., Creagh, S. C., & Tanner, G. (2022). Acoustic radiation from random waves on plates. Journal of Physics A: Mathematical and Theoretical, 55(39), Article 394004. https://doi.org/10.1088/1751-8121/ac8c08

Controlling and simulating the sound radiating from complex structures is of importance in many engineering applications. We calculate the radiated acoustic power from plates with diffuse bending vibrations. We characterise the diffuse field by a two... Read More about Acoustic radiation from random waves on plates.

Wireless power distributions in multi-cavity systems at high frequencies (2021)
Journal Article
Adnan, F., Blakaj, V., Phang, S., Antonsen, T. M., Creagh, S. C., Gradoni, G., & Tanner, G. (2021). Wireless power distributions in multi-cavity systems at high frequencies. Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences, 477(2245), Article 20200228. https://doi.org/10.1098/rspa.2020.0228

The next generations of wireless networks will work in frequency bands ranging from sub-6 GHz up to 100 GHz. Radio signal propagation differs here in several critical aspects from the behaviour in the microwave frequencies currently used. With wavele... Read More about Wireless power distributions in multi-cavity systems at high frequencies.

Tunnelling around bends—Wave scattering in curved shell structures (2020)
Journal Article
Mohammed, N. M., Creagh, S. C., & Tanner, G. (2021). Tunnelling around bends—Wave scattering in curved shell structures. Wave Motion, 101, Article 102697. https://doi.org/10.1016/j.wavemoti.2020.102697

A ray dynamics describing wave transport on curved and smooth thin shells can be obtained from the underlying wave equations via the Eikonal approximation. We analyse mid-frequency effects near the ring frequency for curved plates consisting of a cyl... Read More about Tunnelling around bends—Wave scattering in curved shell structures.

Diffraction of Wigner functions (2020)
Journal Article
Creagh, S., Sieber, M., Gradoni, G., & Tanner, G. K. (2021). Diffraction of Wigner functions. Journal of Physics A: Mathematical and Theoretical, 54(1), Article 015701. https://doi.org/10.1088/1751-8121/abc72a

We describe the contribution of diffractive orbits to semiclassical approximations of Wigner function propagators. These contributions are based on diffractively scattered rays used in the geometrical theory of diffraction (GTD). They provide an exte... Read More about Diffraction of Wigner functions.

Nearfield acoustical holography – a Wigner function approach (2020)
Journal Article
Ramapriya, D. M., Gradoni, G., Creagh, S. C., Tanner, G., Moers, E., & Lopéz Arteaga, I. (2020). Nearfield acoustical holography – a Wigner function approach. Journal of Sound and Vibration, 486, Article 115593. https://doi.org/10.1016/j.jsv.2020.115593

We propose to use Wigner transformation methods as a tool for propagating measured acoustic signals from and towards a source region. We demonstrate the usefulness of the approach both for source reconstruction purposes and as a stable numerical simu... Read More about Nearfield acoustical holography – a Wigner function approach.

Modeling propagation in large deformed step-index fibers using a finite operator method (2019)
Journal Article
Kumar, D. S., Creagh, S. C., Sujecki, S., & Benson, T. M. (2019). Modeling propagation in large deformed step-index fibers using a finite operator method. Journal of the Optical Society of America B, 36(5), 1208-1221. https://doi.org/10.1364/josab.36.001208

© 2019 Optical Society of America. A finite operator model is applied to the propagation of light in deformed step-index fibers. The distribution of the light captured by the fiber from an arbitrary initial excitation is illustrated in the phase spac... Read More about Modeling propagation in large deformed step-index fibers using a finite operator method.

Stochastic electromagnetic field propagation: measurement and modelling (2018)
Journal Article
Gradoni, G., Russer, J., Baharuddin, M. H., Haider, M., Russer, P., Smartt, C., … Thomas, D. W. (2018). Stochastic electromagnetic field propagation: measurement and modelling. Philosophical Transactions A: Mathematical, Physical and Engineering Sciences, 376, Article 20170455. https://doi.org/10.1098/rsta.2017.0455

This paper reviews recent progress in the measurement and modelling of stochastic electromagnetic fields, focusing on propagation approaches based on Wigner functions and the method of moments technique. The respective propagation methods are exempli... Read More about Stochastic electromagnetic field propagation: measurement and modelling.

Elastodynamics on graphs: wave propagation on networks of plates (2018)
Journal Article
Brewer, C., Creagh, S. C., & Tanner, G. (2018). Elastodynamics on graphs: wave propagation on networks of plates. Journal of Physics A: Mathematical and Theoretical, 51(44), Article 445101. https://doi.org/10.1088/1751-8121/aae1d2

We consider the wave dynamics on networks of plates coupled along 1D joints. This set-up can be mapped onto an extension of wave graph systems studied in, for example, quantum graph theory. In the elastic case, different mode-types (flexural, longitu... Read More about Elastodynamics on graphs: wave propagation on networks of plates.

Near-Field MIMO Communication Links (2018)
Journal Article
Phang, S., Ivrlac, M. T., Gradoni, G., Creagh, S. C., Tanner, G., & Nossek, J. A. (2018). Near-Field MIMO Communication Links. IEEE Transactions on Circuits and Systems I: Regular Papers, 65(9), 3027-3036. https://doi.org/10.1109/tcsi.2018.2796305

© 2004-2012 IEEE. A procedure to achieve near-field multiple input multiple output (MIMO) communication with equally strong channels is demonstrated in this paper. This has applications in near-field wireless communications, such as Chip-to-Chip (C2C... Read More about Near-Field MIMO Communication Links.

Near-field scanning and propagation of correlated low-frequency radiated emissions (2017)
Journal Article
Gradoni, G., Madenoor Ramapriya, D., Creagh, S. C., Tanner, G., Baharuddin, M. H., Nasser, H., …Thomas, D. W. (2017). Near-field scanning and propagation of correlated low-frequency radiated emissions. IEEE Transactions on Electromagnetic Compatibility, 60(6), 2045-2048. https://doi.org/10.1109/TEMC.2017.2778046

Electromagnetic radiation from complex printed circuit boards can occur over a broad frequency bandwidth, ranging from hundreds of MHz to tens of GHz. This is becoming a critical issue for assessment of EMC and interoperability as electronic componen... Read More about Near-field scanning and propagation of correlated low-frequency radiated emissions.

Wigner-Function-Based Propagation of Stochastic Field Emissions from Planar Electromagnetic Sources (2017)
Journal Article
Gradoni, G., Arnault, L. R., Creagh, S. C., Tanner, G., Baharuddin, M. H., Smartt, C., & Thomas, D. W. (2018). Wigner-Function-Based Propagation of Stochastic Field Emissions from Planar Electromagnetic Sources. IEEE Transactions on Electromagnetic Compatibility, 60(3), 580-588. https://doi.org/10.1109/TEMC.2017.2738329

© 1964-2012 IEEE. Modeling the electromagnetic radiation from modern digital systems - acting effectively as extended stochastic sources as part of a complex architecture - is a challenging task. We follow an approach here based on measuring and prop... Read More about Wigner-Function-Based Propagation of Stochastic Field Emissions from Planar Electromagnetic Sources.

Design and characterization of a diamond-shaped monopole antenna (2017)
Journal Article
Maricar, M. I., Bahar, A., Greedy, S., Smartt, C., Phang, S., Gradoni, G., …Thomas, D. W. P. (2017). Design and characterization of a diamond-shaped monopole antenna. Microwave and Optical Technology Letters, 59(10), 2695-2698. https://doi.org/10.1002/mop.30790

We report a new planar antenna design in the shape of a diamond. The performance of the antenna design is initially obtained through simulation, then fabricated, and its performance evaluated through experiment. Experimental characterization of the d... Read More about Design and characterization of a diamond-shaped monopole antenna.

Propagating wave correlations in complex systems (2016)
Journal Article
Creagh, S. C., Gradoni, G., Hartmann, T., & Tanner, G. (2016). Propagating wave correlations in complex systems. Journal of Physics A: Mathematical and Theoretical, 50(4), Article 45101. https://doi.org/10.1088/1751-8121/50/4/045101

We describe a novel approach for computing wave correlation functions inside finite spatial domains driven by complex and statistical sources. By exploiting semiclassical approximations, we provide explicit algorithms to calculate the local mean of t... Read More about Propagating wave correlations in complex systems.

Localized single frequency lasing states in a finite parity-time symmetric resonator chain (2016)
Journal Article
Phang, S., Vukovic, A., Creagh, S. C., Sewell, P., Gradoni, G., & Benson, T. M. (2016). Localized single frequency lasing states in a finite parity-time symmetric resonator chain. Scientific Reports, 6, Article e20499. https://doi.org/10.1038/srep20499

In this paper a practical case of a finite periodic Parity Time chain made of resonant dielectric cylinders is considered. The paper analyzes a more general case where PT symmetry is achieved by modulating both the real and imaginary part of the mate... Read More about Localized single frequency lasing states in a finite parity-time symmetric resonator chain.

A phase-space approach for propagating field–field correlation functions (2015)
Journal Article
Gradoni, G., Creagh, S. C., Tanner, G., Smartt, C., & Thomas, D. W. (2015). A phase-space approach for propagating field–field correlation functions. New Journal of Physics, 17, Article 093027. https://doi.org/10.1088/1367-2630/17/9/093027

We show that radiation from complex and inherently random but correlated wave sources can be modelled efficiently by using an approach based on the Wigner distribution function. Our method exploits the connection between correlation functions and the... Read More about A phase-space approach for propagating field–field correlation functions.

Parity-time symmetric coupled microresonators with a dispersive gain/loss (2015)
Journal Article
Phang, S., Vukovic, A., Creagh, S. C., Benson, T. M., Sewell, P. D., & Gradoni, G. (2015). Parity-time symmetric coupled microresonators with a dispersive gain/loss. Optics Express, 23(9), 11493-11507. https://doi.org/10.1364/oe.23.011493

The paper reports on the coupling of Parity-Time (PT)-symmetric whispering gallery resonators with realistic material and gain/loss models. Response of the PT system is analyzed for the case of low and high material and gain dispersion, and also for... Read More about Parity-time symmetric coupled microresonators with a dispersive gain/loss.

In–out decomposition of boundary integral equations (2013)
Journal Article
Creagh, S. C., Hamdin, H. B., & Tanner, G. (2013). In–out decomposition of boundary integral equations. Journal of Physics A: Mathematical and Theoretical, 46(43), Article 435203. https://doi.org/10.1088/1751-8113/46/43/435203

We propose a reformulation of the boundary integral equations for the Helmholtz equation in a domain in terms of incoming and outgoing boundary waves. We obtain transfer operator descriptions which are exact and thus incorporate features such as diff... Read More about In–out decomposition of boundary integral equations.

Voltage and current spectra for matrix power converters (2009)
Journal Article
Cox, S. M., & Creagh, S. C. (2009). Voltage and current spectra for matrix power converters. SIAM Journal on Applied Mathematics, 69(5), https://doi.org/10.1137/080718863

Matrix power converters are used for transforming one alternating-current power supply to another, with different peak voltage and frequency. There are three input lines, with sinusoidally varying voltages which are 120? out of phase one from another... Read More about Voltage and current spectra for matrix power converters.