Essays about: "grating"

Showing result 1 - 5 of 61 essays containing the word grating.

  1. 1. A Novel Method for Measuring Low Energy Excitations with BLS

    University essay from Uppsala universitet/Materialfysik

    Author : Christopher Borchert; [2024]
    Keywords : ;

    Abstract : This report presents the work done on an optical setup combining Raman and BLS spectroscopy and discusses the achieved improvements of the system. After some general optimization and minor redesigning, a new alternative beam path was implemented. READ MORE

  3. 2. Design of a grating lobe mitigated antenna array architecture integrated with low loss PCB filtering structures

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

    Author : Eduardo Salvador Lopez; [2023]
    Keywords : Band-pass filters; Beam forming networks; Irregular subarrays; Particle Swarm Optimization; PCB; Penrose tessellation; Planar phased arrays; Quantization lobes; Scanning; Suspended stripline; Bandpassfilter; lobformning; matningsnätverk; Irreguljära gruppantenner; Particle Swarm Optimization; PCB; Penrose tessellation; Plana fasade gruppantenner; sidlober; Utstyrningsvinkel; Suspended stripline;

    Abstract : Massive multiple input multiple output - MIMO systems are a reality and modern communication systems rely upon this technology to cope with the increasing need for capacity and network usage. Antenna arrays are at the heart of the of the massive-MIMO system and are the enabling technology. READ MORE

  4. 3. Analyzing Synthetic Spider Silk-based Diffraction Grids for the Sunshade Project

    University essay from KTH/Skolan för teknikvetenskap (SCI)

    Author : Johanna D'Ciofalo Khodaverdian; Amira Karlsson; [2023]
    Keywords : Sunshade project; Diffraction grating; Artificial spider silk; Climate change; Geoengineering;

    Abstract : To mitigate climate change a proposed space-based geoengineering solutionis to screen off solar irradiance by placing a membrane in between the Earthand the Sun. The feasibility of such a project largely depends on minimizingthe mass of the shading screen and as an extension to the Sunshade projectthis thesis investigated how such a low-mass membrane could be designed. READ MORE

  5. 4. Ray-Tracing Modeling of Grating Lobe Level Reduction by Using a Dielectric Dome Antenna

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

    Author : Lukas Jonasson; [2023]
    Keywords : Array antenna; Dielectric dome; Ray-Tracing; Grating lobe; Particle Swarm optimization; Gruppantenn; Dielektrisk kupol; Strålspårning; Gallerlob; Particle Swarm optimering;

    Abstract : With the newly deployed fifth-generation telecommunications system and upcoming sixth-generation, high-gain antennas with hemispherical scanning capabilities are of high interest. Phased array antennas allow for fast scanning capabilities with electronic beam-steering. READ MORE

  6. 5. Towards a setup for narrowband terahertz generation through difference-frequency mixing of chirped ultrashort pulses

    University essay from Lunds universitet/Atomfysik; Lunds universitet/Fysiska institutionen

    Author : Isa Clementsson; [2023]
    Keywords : Physics and Astronomy;

    Abstract : Terahertz radiation is a useful tool for inducing lower-energy excitations in matter, where it can be used to cause structural changes through direct interaction with the crystal lattice. Sub-picosecond optical pulses can be used to generate intense broadband terahertz pulses through optical rectification in nonlinear crystals, reaching peak electric fields of several MV/m and conversion efficiencies as high as a few percent. READ MORE