Sökning: "signal resolution"

Visar resultat 16 - 20 av 394 avhandlingar innehållade orden signal resolution.

  1. 16. Cross-Correlator Implementations Enabling Aperture Synthesis for Geostationary-Based Remote Sensing

    Författare :Erik J Ryman; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; full-custom; signal processing; synthetic aperture; Cross-correlation; interferometric imaging; ASIC; remote sensing;

    Sammanfattning : An ever-increasing demand for weather prediction and high climate modelling accuracy drives the need for better atmospheric data collection. These demands include better spatial and temporal coverage of mainly humidity and temperature distributions in the atmosphere. LÄS MER

  2. 17. Characterization and Correction of Analog-to-Digital Converters

    Författare :Henrik Lundin; Peter Händel; Mikael Skoglund; Paolo Carbone; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; analog-to-digital converter; ADC; correction; post-correction; look-up table; characterization; calibration; Signal processing; Signalbehandling;

    Sammanfattning : Denna avhandling behandlar analog-digitalomvandling. I synnerhet behandlas postkorrektion av analog-digitalomvandlare (A/D-omvandlare). A/D-omvandlare är i praktiken behäftade med vissa fel som i sin tur ger upphov till distorsion i omvandlarens utsignal. LÄS MER

  3. 18. Estimation of synchronization parameters

    Författare :Jaap van de Beek; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Signalbehandling; Signal Processing;

    Sammanfattning : This thesis deals with the estimation of synchronization parameters in {Orthogonal Frequency Division Multiplexing} (OFDM) communication systems and in active ultrasonic measuring systems. Estimation methods for the timing and frequency offset and for the attenuation taps of the frequency selective channel are presented and investigated. LÄS MER

  4. 19. Combining analytical and iterative reconstruction in helical cone-beam CT

    Författare :Johan Sunnegårdh; Gösta Granlund; Per-Erik Danielsson; Michel Defrise; Linköpings universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; cone-beam tomography; forward projection; image reconstruction; iterative reconstruction; ordered subsets; regularization; WFBP; Signal processing; Signalbehandling;

    Sammanfattning : Contemporary algorithms employed for reconstruction of 3D volumes from helical cone beam projections are so called non-exact algorithms. This means that the reconstructed volumes contain artifacts irrespective of the detector resolution and number of projection angles employed in the process. LÄS MER

  5. 20. Ultrasonic Arrays for Sensing and Beamforming of Lamb Waves

    Författare :Marcus Engholm; Tadeusz Stepinski; Paul D. Wilcox; Uppsala universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; imaging; array processing; guided waves; Lamb waves; dispersive waves; multi-modal waves; spatial filtering; mode suppression; resonant ultrasound; transducer design; direction of arrival estimation; adaptive beamforming; Signal processing; Signalbehandling; Electronic measurement and instrumentation; Elektronisk mät- och apparatteknik;

    Sammanfattning : Non-destructive testing (NDT) techniques are critical to ensure integrity and safety of engineered structures. Structural health monitoring (SHM) is considered as the next step in the field enabling continuous monitoring of structures. LÄS MER