Essays about: "model radiation field"

Showing result 11 - 15 of 58 essays containing the words model radiation field.

  1. 11. Far-field pattern synthesis of transmitarray antennas using convex optimization techniques

    University essay from KTH/Tillämpad fysik

    Author : Marie Defives; [2022]
    Keywords : Applied physics; Transmitarray antennas; convex optimization; Tillämpad fysik; Transmitarray-antenner; konvex optimering;

    Abstract : Transmitarrays antennas (TAs) can be seen as the planar counterpart of optical lenses. They are composed of thin radiating elements (unit cells) which introduce different local phase shifts on an incident electromagnetic wave, emitted by a primary source, and re-radiate it. READ MORE

  3. 12. Antenna Implants and Feasibility of Performance Limitations : AStudy of Radiation Efficiency on Electrically Small Antenna Implants with Finite Conductivity and Size

    University essay from KTH/Skolan för elektroteknik och datavetenskap (EECS)

    Author : Erik Algarp; [2022]
    Keywords : Antennaimplant; Medical Implant CommunicationSystem; Electrically small antenna; Electric dipole; Magnetic dipole; Fundamental bounds; Performance limits; Radiation efficiency; Conductor loss; Antennimplant; Medical Implant Communication System; Elektriskt små antenner; Elektrisk dipol; Magnetisk dipol; Fundamentala begränsningar; Prestandagränser; Strålningseffektivitet; Metallförlust;

    Abstract : Antenna implants are used to establish a telemetry link to enable wireless data transfer, suitable for telemedicine and other medical applications. Inbody environments with water-based tissues lead to severe power absorption, making signal strength and radiation efficiency challenging yet central performance aspects of antenna implants. READ MORE

  4. 13. Estimating Properties of a Young Pulsar through X-ray Observations - An Investigation of Parameter Dependence

    University essay from KTH/Fysik

    Author : Lurin Ali; [2022]
    Keywords : Pulsar; Neutron star; Supernova;

    Abstract : Studying the properties of newborn neutron stars is a complicated matter since they cannot be directly observed. Neutron stars are born when some massive stars go supernova (SN), where the expelled material from the explosion goes on to shield the young neutron star from our view by absorbing its radiation. READ MORE

  5. 14. Electrodynamic field at spatial infinity

    University essay from KTH/Fysik

    Author : Jakob Myhrman; [2022]
    Keywords : Spatial infinity; Conformal rescaling; Minkowski space; Penrose Diagram; Einstein universe; Newman-Penrose formalism; Sigma-process; Resolution of singularities; Maxwell s equations; Cylinder at spatial infinity; Rumslig oändlighet; Konform omskalning; Minkowski rummet; Penrose Diagram; Einsteins universum; Newman-Penrose formalismen; Sigma-processen; Singularitetupplösning; Maxwells ekvationer; Cylindern vid rumslig oändlighet;

    Abstract : The treatment of spatial infinity is one of the remaining major open problems in the theory of isolated self-gravitating systems. Especially when one wants to model scattering of gravitational radiation in spacetime. In this thesis the conformal theory is used to study simple electromagnetic fields, close to spatial infinity. READ MORE

  6. 15. Primordial Gravitational Waves and ultra-light Dark Matter in a complex singlet extended Standard Model

    University essay from Lunds universitet/Partikel- och kärnfysik; Lunds universitet/Teoretisk partikelfysik - Geonomgår omorganisation

    Author : Sara Wildenor; [2021]
    Keywords : theoretical physics; gravitational waves; dark matter; complex singlet extended standard model; LISA; BBO; DECIGO; Physics and Astronomy;

    Abstract : In this thesis, the consequences of extending the internal symmetries of the standard model with a complex singlet scalar field, are investigated in terms of dark matter phenomenology and the possibility of primordial gravitational wave detection utilizing space based laser interferometry. The scalar potential of the model is constructed with a Z2 symmetry, which allows for the retainment of a linear and a quadratic coupling parameter, as well as a stable dark matter candidate, and an additional non-zero vacuum expectation value for the real component of the scalar field. READ MORE