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Bibliography (pages 144-150).
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| Format: | Thesis |
| Language: | English |
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Department of Electrical Engineering
2016
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| _version_ | 1867613195889278976 |
|---|---|
| access_status_str | Open Access |
| author | Horrell, Jasper M |
| author2 | Inggs, Michael |
| author_browse | Horrell, Jasper M Inggs, Michael |
| author_facet | Inggs, Michael Horrell, Jasper M |
| author_sort | Horrell, Jasper M |
| collection | Thesis |
| description | Bibliography (pages 144-150). |
| format | Thesis |
| id | oai:open.uct.ac.za:11427/16092 |
| institution | University of Cape Town (South Africa) |
| language | eng |
| last_indexed | 2026-06-10T12:32:17.361Z |
| license_str | Not specified — see source repository |
| provenance_str_mv | Harvested via OAI-PMH from UCTD — University of Cape Town Open Access Repository |
| publishDate | 2016 |
| publishDateRange | 2016 |
| publishDateSort | 2016 |
| publisher | Department of Electrical Engineering |
| publisherStr | Department of Electrical Engineering |
| record_format | dspace |
| source_str | UCTD — University of Cape Town Open Access Repository |
| spelling | oai:open.uct.ac.za:11427/16092 Range-doppler synthetic aperture radar processing at VHF frequencies Horrell, Jasper M Inggs, Michael Electrical Engineering Bibliography (pages 144-150). This thesis focuses on the application of range-Doppler processing at VHF frequencies for wide azimuth beam, airborne, stripmap SAR systems with zero Doppler centroid and modest pulse bandwidths relative to the carrier frequency (simulations less than 30 percent). Such a system is the South African SAR (SASAR) VHF sensor. The theory of such SAR operation is addressed. In general, closed form analytical expressions for range compressed, range-Doppler domain signals do not exist. Thus, in this work, extensive use is made of simulation. Using simulated SAR signals with severe range curvature, the regions of applicability of standard range-Doppler processing, when applied without Doppler frequency dependent secondary range compression, are investigated for a range of processing parameters in the frequency range of 100 MHz to 200 MHz. The effects on the range impulse response of centre frequency, target closest approach range and nominal range resolution are investigated, each for a range of processed azimuth resolutions. Information is presented in the form of plots showing the degradation in the range resolution and in the form of tabular results which also include the range peak- and integrated side lobe levels and the non-linear phase error in the Fourier domain. An extension to range-Doppler processing, suggested to the candidate by Michael Jin, is demonstrated to provide significantly improved performance over the standard range-Doppler processor for signals with severe range curvature. The basic idea of the extended algorithm, first published by Raney and Vachon in 1989 and applied in the context of a narrow beam, squinted SAR, is to make an initial correction to a reference range through a multiplication with a reference function in the 2-D frequency domain. This is followed by a residual range curvature and azimuth focusing operation in the range-Doppler domain. Airborne motion compensation strategies for flight path reconstruction are discussed. In addition, an ERIM-developed approach for efficiently including an azimuth dependence for wide beam motion compensation is discussed in the context of the SASAR system. An overview of the SASAR VHF project, the experience gained, and the encouraging results from the processing of the data from the first radiating flights, is presented. A full Statement of Originality is given. 2016-01-02T04:19:32Z 2016-01-02T04:19:32Z 1999 Doctoral Thesis Doctoral PhD http://hdl.handle.net/11427/16092 eng application/pdf Department of Electrical Engineering Faculty of Engineering and the Built Environment University of Cape Town |
| spellingShingle | Electrical Engineering Horrell, Jasper M Range-doppler synthetic aperture radar processing at VHF frequencies |
| thesis_degree_str | Doctoral |
| title | Range-doppler synthetic aperture radar processing at VHF frequencies |
| title_full | Range-doppler synthetic aperture radar processing at VHF frequencies |
| title_fullStr | Range-doppler synthetic aperture radar processing at VHF frequencies |
| title_full_unstemmed | Range-doppler synthetic aperture radar processing at VHF frequencies |
| title_short | Range-doppler synthetic aperture radar processing at VHF frequencies |
| title_sort | range doppler synthetic aperture radar processing at vhf frequencies |
| topic | Electrical Engineering |
| url | http://hdl.handle.net/11427/16092 |
| work_keys_str_mv | AT horrelljasperm rangedopplersyntheticapertureradarprocessingatvhffrequencies |