Sökning: "Narrow frequency band"

Visar resultat 1 - 5 av 33 uppsatser innehållade orden Narrow frequency band.

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

    Master-uppsats, KTH/Skolan för elektroteknik och datavetenskap (EECS)

    Författare :Eduardo Salvador Lopez; [2023]
    Nyckelord :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;

    Sammanfattning : 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. LÄS MER

  3. 2. Filtering Pressure Oscillations in a Common Rail Pressure Signal with IIR Notch Filters for Injected Fuel Amount Estimation

    Master-uppsats, KTH/Skolan för industriell teknik och management (ITM)

    Författare :Marcus Akkila; Denis Ramsden; [2023]
    Nyckelord :DSP; Water hammer effect; IIR; Common-rail; Injected fuel amount estimation; Notch filter; Water hammer effect; IIR; Digital signalbehandling; Injektionsmängd; Common-rail; bandstoppfilter;

    Sammanfattning : This project concerns an inline six-cylinder (I6) diesel truck engine equipped with common-rail injection system. It has been done at the Swedish truck manufacturer Scania CV AB. The main focus is digital signal processing of the rail pressure sensor signal from the injection system. LÄS MER

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

    Master-uppsats, Lunds universitet/Atomfysik; Lunds universitet/Fysiska institutionen

    Författare :Isa Clementsson; [2023]
    Nyckelord :Physics and Astronomy;

    Sammanfattning : 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. LÄS MER

  5. 4. Portable HF Antennas for Concurrent Multiband Systems

    Master-uppsats, KTH/Skolan för elektroteknik och datavetenskap (EECS)

    Författare :Sambhav Malhotra; [2022]
    Nyckelord :Antenna; HF; Skywave Propogation; Multiband;

    Sammanfattning : Current HF communication systems are confined to transmit in relatively narrow frequency band of a few 100 kHz at the time. The problems with limited bandwidth accumulate in HF-networks with multiple links and such networks are therefore hardly “internet capable” today. LÄS MER

  7. 5. Design of Autonomous Underwater Vehicle’s (AUV) Antenna System

    Master-uppsats, KTH/Skolan för elektroteknik och datavetenskap (EECS)

    Författare :Chengzhuang Zhou; [2021]
    Nyckelord :AUV Antenna; Printed Dipole Antenna; Broadband Antenna; AUV antenna; Printed dipole antenna; Broadband antenna;

    Sammanfattning : The ocean symbolizes mystery, passion, and power. However, most of the ocean, about 80 %, is unknown to humans. AUVs (Autonomous Underwater Vehicles) provide a platform where terrain mapping, the biodiversity, and the resource survey of the ocean become accessible. LÄS MER