Sökning: "Harmonic sampling"

Visar resultat 1 - 5 av 16 avhandlingar innehållade orden Harmonic sampling.

  1. 1. Numerical Methods for Aeroacoustic Analysis of Turbomachines

    Författare :Daniel Lindblad; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Stability Analysis; Acoustic Analogy; Tonal Noise; Nonreflecting Boundary Conditions; Duct Modes; Turbomachinery; Harmonic Balance; Ffowcs Williams - Hawkings; Time Sampling; Aliasing;

    Sammanfattning : Numerical simulations are important tools for developing new aircraft that can meet future needs. When numerical simulations are used to compute aircraft noise, a two-step procedure is often employed. In the first step, the noise sources are determined using, e.g. LÄS MER

  3. 2. Control and Analysis of Pulse-Modulated Systems

    Författare :Stefan Almér; Ulf Jönsson; Gilead Tadmor; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Pulse-width modulation; Periodic systems; Stability analysis; Harmonic analysis; Lyapunov methods; Dynamic phasors; Harmonic transfer function; Switched mode power converters; Sampled data modeling; H-infinity synthesis; Optimization; systems theory; Optimeringslära; systemteori;

    Sammanfattning : The thesis consists of an introduction and four appended papers. In the introduction we give an overview of pulse-modulated systems and provide a few examples of such systems. Furthermore, we introduce the so-called dynamic phasor model which is used as a basis for analysis in two of the appended papers. LÄS MER

  4. 3. Modeling and Sampling of Spectrally Structured Signals

    Författare :Filip Elvander; Statistical Signal Processing Group; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; spectral estimation; parameter estimation; optimal mass transport; covariance interpolation; misspecified models; inharmonicity;

    Sammanfattning : This thesis consists of five papers concerned with the modeling of stochastic signals, as well as deterministic signals in stochastic noise, exhibiting different kinds of structure. This structure is manifested as the existence of finite-dimensional parameterizations, and/or in the geometry of the signals' spectral representations. LÄS MER

  5. 4. A Harmonic-Oscillator Design Methodology Based on Describing Functions

    Författare :Jesper Bank; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; oscillator design efficiency; phase noise; impulse sensitivity function; design methodology; amplitude control; frequency tuning; oscillator; describing function;

    Sammanfattning : Oscillators are present in most electronic equipment where they provide timing information, for example as sampling clocks in analog-to-digital converters or as radio carriers in wireless communications. To design an oscillator, we must have knowledge of the properties and the operation of oscillators. LÄS MER

  7. 5. Direct RF sampling receivers for wireless systems in CMOS technology

    Författare :Darius Jakonis; Linköpings universitet; []
    Nyckelord :TECHNOLOGY; TEKNIKVETENSKAP;

    Sammanfattning : The fast development of wireless communication systems asks for more flexible and more cost-effective radio architectures. A long term goal is a software defined radio, where communication standards are chosen by reconfiguration of hardware. LÄS MER