Signal Generation for FMCW Ultra-Wideband Radar

III ACKNOWLEDGEMENTS I would like to thank my advisor Dr. Carlton Leuschen for his guidance and expert advice that helped me successfully complete my thesis and my masters. I would like to thank Dr. Prasad Gogineni for giving me an opportunity to be a part of the CReSIS project and guiding me all throughout my research. I would like Dr. Chris Allen for his helpful guidance and inputs during the weekly meetings. I would like to extend my sincere thanks to Dr. Fernando Rodriguez-Morales for guiding me and being there to help me whenever I needed any. I would like to thank John Ledford for helping me and answering my questions. I would like to extend special thanks Dr. Sarah Seguin for giving me the support I needed. Finally I would like to thank my husband for being very supportive. I also would like to thank my parents, my brother and my sister for their support and encouragement. I thank all my friends at CReSIS and KU for making my masters studies an enjoyable experience. ABSTRACT One of the greatest concerns facing the planet earth today is global warming. Globally the temperatures have risen and this has caused rise in sea level. Since a large percentage of the population lives near the coast sea level rise could have potentially catastrophic consequences. One of the largest uncertainties in projections of sea level rise is the changes of mass-balance of the ice sheets of Greenland and Antarctica. To predict the rise in sea level we need accurate measurements of mass-balance. One of the methods of determining mass-balance is through surface ice elevation measurements. In order to measure surface ice elevation, map near surface internal layers and measure the thickness of snow over sea ice Ultra-Wideband (UWB) Frequency-Modulated Continuous-Wave Radars are being developed at CReSIS. FMCW radars are low-cost low-power solution to obtain very fine range resolution. However, nonlinearities present in the transmit frequency sweep of the FMCW radar can deteriorate the range resolution. The main objective of the thesis was to produce an ultra linear transmit chirp signal for UWB Radars. This was done by using the Voltage-Controlled-Oscillator (VCO) in a Phase-Locked Loop configuration. To check the linearity of the chirp beat frequency was generated using delay line as a synthetic target and captured on the oscilloscope. This beat signal data were further analyzed for linearity and we found that the frequency …