Sökning: "frequency conversion"

Visar resultat 11 - 15 av 194 avhandlingar innehållade orden frequency conversion.

  1. 11. Design and characterisation of terahertz Schottky diode harmonic mixers

    Författare :Divya Jayasankar; RISE Research Institutes of Sweden; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Schottky diodes; Phase locking; Harmonic mixers; Heterodyne receivers; Terahertz electronics; Frequency stabilisation; Frequency converters;

    Sammanfattning : Efficient, compact, and reliable terahertz frequency converters preferably operating at ambient temperature are crucial for stabilising far-infrared optical sources. This thesis focuses on the design and characterisation of terahertz Schottky diode harmonic mixers for frequency stabilisation of quantum-cascade lasers. LÄS MER

  3. 12. Short Pulses in Engineered Nonlinear Media

    Författare :Stefan Holmgren; Fredrik Laurell; Derryck Reid; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; nonlinear optics; KTiOPO4; frequency conversion; mode-locked lasers; ultra-fast lasers; visible lasers; short pulses; ultrafast nonlinear optics; diagnostic applications of nonlinear optics; nonlinear optical materials; Physics; Fysik;

    Sammanfattning : Short optical pulses and engineered nonlinear media is a powerful combination. Mode locked pulses exhibit high peak powers and short pulse duration and the engineered ferro-electric KTiOPO4 facilitates several different nonlinear processes. LÄS MER

  4. 13. Components based on optical fibers with internal electrodes

    Författare :Niklas Myrén; KTH; []
    Nyckelord :Poling; twinhole fiber; fiber electrodes; silver film electrodes; silver diffusion; quasi-phase matching; optical switching; frequency conversion; optical modulation;

    Sammanfattning : The topic of this thesis is development ofdevices fortelecom applications based on poled optical fibers. The focusis on two different specific functions, wavelength conversionand optical switching.Optical switching is demonstrated in a poled optical fiberat telecom wavelengths (~1.55 mm). LÄS MER

  5. 14. Millimeter-wave Transceiver ICs for Ultrahigh Data Rate Communications Using Advanced III-V and Silicon Technologies

    Författare :Sona Carpenter; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; D-band; frequency multiplier; 110-170 GHz; QPSK; demodulator; I Q modulator; transmitter; high-order modulation; receiver; high data rate; single chip; SiGe BiCMOS; QAM; InP DHBT; direct conversion; Gilbert-cell mixer; millimeter-wave communication; 5G; MMIC; point-to-point radio.;

    Sammanfattning : Today’s main driving parameter for radio transceiver research is the ability to provide high capacity while maintaining low cost, small form factor, and low power consumption. Direct conversion architectures (due to the feasibility of monolithic integration) at millimeter-wave (due to wideband availability) have attracted large interest in recent years because of their potential to meet these demands. LÄS MER

  7. 15. Nanosecond optical parametric oscillators and amplifiers based on periodically poled KTiOPO4

    Författare :Jonas Hellström; KTH; []
    Nyckelord :optical parametric oscillators; optica parametric amplifiers; quasi-phasematching; KTiOPO4; nonlinear optics; frequency conversion; periodic electric field poling; ferroelectrics; high-order second harmonic generation; electro-optic effect;

    Sammanfattning : Optical parametric oscillators (OPOs) and optical parametricamplifiers (OPAs) constitute a class of optical frequencyconverting devices that have many possible applications, e.g.in range finding, molecular spectroscopy and medicine. LÄS MER