FMCW-SAR System For Near Distance Imaging Applications

  • Author / Creator
    Ting, Jui wen
  • A combination of frequency-modulated continuous-wave (FMCW) technology with synthetic aperture radar (SAR) principles is a highly sought after method as it leads to a compact and cost effective high resolution near distance imaging system. However, there are a few design issues associated with FMCW radar systems that need to be addressed in order to design an optimal FMCW SAR imaging system. One of the limiting factors of FMCW radars is that the ramp signal modulates the received signal, which limits the minimum achievable range resolution. In addition, the voltage controlled oscillator (VCO) adds a certain degree of phase noise and nonlinearity to the transmitted signal that degrades the signal-to-noise ratio (SNR), range accuracy and image resolution. To resolve these issues, a multitude of hardware and software approaches have been proposed for the suppression of phase noise and nonlinearity of the transmitted signal. However, these approaches resolve only individual issues, limiting their applicability in the design of FMCW SAR imaging systems. This work seeks to overcome the three design issues mentioned above through the development of simulation platforms, which has been shown to be well-suited for the comprehensive study of these effects. A signal processing procedure with system calibration methods to mitigate the effects of deramp, phase noise and nonlinearity of the VCO on the beat spectrum is proposed. Additionally, the effect of bandwidth, integration angle and phase noise of the received pulses on the SAR image resolution in both range and cross-range directions are comprehensively studied. To improve the range accuracy, different calibration methods are also comprehensively studied. To demonstrate the effectiveness and versatility of the proposed signal processing procedure, an S-band FMCW radar system, using off-the-shelf components, is designed for near distance target imaging using linear and circular SAR techniques. The reconstructed images show the improvement of image quality and accuracy in the target position. Finally, several avenues of further study and applications are suggested.

  • Subjects / Keywords
  • Graduation date
  • Type of Item
  • Degree
    Master of Science
  • DOI
  • License
    This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.
  • Language
  • Institution
    University of Alberta
  • Degree level
  • Department
    • Department of Electrical and Computer Engineering
  • Specialization
    • Electromagnetics and Microwaves
  • Supervisor / co-supervisor and their department(s)
    • Karumudi, Rambabu (Electrical and Computer Engineering)
  • Examining committee members and their departments
    • Moez, Kambiz (Electrical and Computer Engineering)
    • Jing, Yindi (Electrical and Computer Engineering)