eprintid: 1534631 rev_number: 21 eprint_status: archive userid: 608 dir: disk0/01/53/46/31 datestamp: 2017-03-02 11:04:32 lastmod: 2019-10-17 08:02:47 status_changed: 2017-03-02 11:04:32 type: thesis metadata_visibility: show creators_name: Sego, DJ title: Three Dimensional Bistatic Tomography Using HDTV ispublished: unpub divisions: A01 divisions: B04 divisions: C05 divisions: F46 abstract: The thesis begins with a review of the principles of diffraction and reflection tomography; starting with the analytic solution to the inhomogeneous Helmholtz equation, after linearization by the Born approximation (the weak scatterer solution), and arriving at the Filtered Back Projection (Propagation) method of reconstruction. This is followed by a heuristic derivation more directly couched in the radar imaging context, without the rigor of the general inverse problem solution and more closely resembling an imaging turntable or inverse synthetic aperture radar. The heuristic derivation leads into the concept of the line integral and projections (the Radon Transform), followed by more general geometries where the plane wave approximation is invalid. We proceed next to study of the dependency of reconstruction on the space-frequency trajectory, combining the spatial aperture and waveform. Two and three dimensional apertures, monostatic and bistatic, fully and sparsely sampled and including partial apertures, with controlled waveforms (CW and pulsed, with and without modulation) define the filling of k-space and concomitant reconstruction performance. Theoretical developments in the first half of the thesis are applied to the specific example of bistatic tomographic imaging using High Definition Television (HDTV); the United States version of DVB-T. Modeling of the HDTV waveform using pseudonoise modulation to represent the hybrid 8VSB HDTV scheme and the move-stop-move approximation established the imaging potential, employing an idealized, isotropic 18 scatterer. As the move-stop-move approximation places a limitation on integration time (in cross correlation/pulse compression) due to transmitter/receiver motion, an exact solution for compensation of Doppler distortion is derived. The concept is tested with the assembly and flight test of a bistatic radar system employing software-defined radios (SDR). A three dimensional, bistatic collection aperture, exploiting an elevated commercial HDTV transmitter, is focused to demonstrate the principle. This work, to the best of our knowledge, represents a first in the formation of three dimensional images using bistatically-exploited television transmitters. date: 2017-01-28 oa_status: green full_text_type: other thesis_class: doctoral_open language: eng thesis_view: UCL_Thesis primo: open primo_central: open_green verified: verified_manual elements_id: 1200174 lyricists_name: Sego, Daniel lyricists_id: DJSEG39 actors_name: Sego, Daniel actors_name: Zahnhausen-Stuber, Petra actors_id: DJSEG39 actors_id: PMZAH20 actors_role: owner actors_role: impersonator full_text_status: public pages: 375 institution: UCL (University College London) department: Electronic and Electrical Engineering thesis_type: Doctoral citation: Sego, DJ; (2017) Three Dimensional Bistatic Tomography Using HDTV. Doctoral thesis , UCL (University College London). Green open access document_url: https://discovery.ucl.ac.uk/id/eprint/1534631/1/Sego_Thesis%20with%20Corrections%20Sego%20950771%20UCL%20RPS.pdf