Sökning: "low-noise amplifier"

Visar resultat 31 - 35 av 58 avhandlingar innehållade orden low-noise amplifier.

  1. 31. Heterostructure Field Effect Transistors and Millimeter Wave Integrated Circuits

    Författare :Niklas Rorsman; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; subharmonic; resistive mixer; Modulation Doped Field Effect Transistor MODFET ; heterostructure field effect transistor HFET ; monolithic microwave integrated circuits MMIC ; frequency multiplier; amplifier; III-V semiconductor; small signal model; electron beam lithography; High Electron Mobility Transistor HEMT ; large signal model; pseudomorphic;

    Sammanfattning : This thesis deals with the research and development of HFETs and HFET based circuits. One of the main aims of the work presented in this thesis has been to develop processes to fabricate state of the art devices and circuits. LÄS MER

  3. 32. Three-wave mixing in Josephson travelling-wave parametric amplifiers

    Författare :Hampus Renberg Nilsson; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; three-wave mixing; lumped-element; four-wave mixing; SNAIL; Josephson junction; travelling-wave parametric amplifier; parametric amplifier; parametric amplification; resonant phase matching.; rf-SQUID;

    Sammanfattning : This work explores possibilities of building a wide-band, quantum-limited low-noise amplifier by means of three-wave mixing (3WM) in different kinds of Josephson travelling-wave parametric amplifiers (TWPAs). We extend the theory of the continuous three-mode model to include any number of up-converted modes in the small frequency limit where the frequency dispersion is close to linear. LÄS MER

  4. 33. Phase-Sensitive Fiber Optic Parametric Amplifier and Their Applications in Optical Communications

    Författare :Carl Peter Lundström; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Sammanfattning : This thesis deals with experimental and theoretical aspects of the phase-sensitive fiber optic parametric amplifier (FOPA) and their applications. FOPAs can be oper- ated as both phase-insensitive and phase-sensitive amplifiers (PSAs), with the latter requiring phase-locked input waves, which, until recently, has limited their practi- cal use. LÄS MER

  5. 34. Phase Sensitive Amplifiers for Free-Space Optical Communications

    Författare :Ravikiran Kakarla; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Phase sensitive amplifier; sensitivity; optical injection locking; noisefigure;

    Sammanfattning : The demand for high data rate free-space communications is increasing due to the planned future space exploration missions. In the next few years there is a need to increase the speed by 100 times according to NASA, and this necessitates that transmission systems operate at higher carrier frequencies. LÄS MER

  7. 35. Linearity Enhancements of Receiver Front-end Circuits for Wireless Communication

    Författare :Mohammed Abdulaziz; Institutionen för elektro- och informationsteknik; []
    Nyckelord :CMOS; receivers; operational transconductance amplifiers; filtering; channel select filters; stability; low noise amplifiers; linearization; carrier aggregation; spectrum sensing;

    Sammanfattning : Technology scaling in advanced CMOS nodes has been very successful in reducing the cost and increasing the operating frequency, however, it has also resulted in reduced transistor intrinsic gain and increased thermal noise coefficient, and most importantly, deteriorated linearity performance. At the same time, advanced wireless communication standards offer ever increasing data rates and pose more stringent requirements on coexistence, leading to very stringent linearity requirements. LÄS MER