{"id":{"repo_id":"cape-town","oai_identifier":"oai:open.uct.ac.za:11427/9565"},"canonical_url":"https://search.dev.ndltd.org/etd/cape-town/oai:open.uct.ac.za:11427/9565","repository":{"repo_id":"cape-town","name":"University of Cape Town","base_url":"https://open.uct.ac.za/oai/request"},"display":{"title":"Investigation into variable shift keying using direct sequence spread spectrum techniques","abstract":"This thesis reports the research done into a relatively unknown modulation scheme called VPSK (Variable Phase Shift Keying) and the use of DSSS (Direct Sequence Spread Spectrum) techniques to achieve carrier synchronization and hence coherent demodulation in the receiver. VPSK is a new and relatively unknown modulation scheme in which data bits are encoded using patented algorithms designed by Millerand Walker. VPSK modulation is a SSBSC (Single Sideband Suppressed Carrier) modulation scheme with good bandwidth efficiency. Data is coherently demodulated in the receiver. In existing VPSK systems, the locally generated carrier in the receiver is synchronized to an integer multiple of the symbol clock frequency to allow coherent demodulation. This coherent method of demodulation is not optimum if the channel over which information must be transmitted is a non-Gaussian channel, or has multi-path characteristics.","abstract_html":"This thesis reports the research done into a relatively unknown modulation scheme called VPSK (Variable Phase Shift Keying) and the use of DSSS (Direct Sequence Spread Spectrum) techniques to achieve carrier synchronization and hence coherent demodulation in the receiver. VPSK is a new and relatively unknown modulation scheme in which data bits are encoded using patented algorithms designed by Millerand Walker. VPSK modulation is a SSBSC (Single Sideband Suppressed Carrier) modulation scheme with good bandwidth efficiency. Data is coherently demodulated in the receiver. In existing VPSK systems, the locally generated carrier in the receiver is synchronized to an integer multiple of the symbol clock frequency to allow coherent demodulation. This coherent method of demodulation is not optimum if the channel over which information must be transmitted is a non-Gaussian channel, or has multi-path characteristics.","abstract_has_math":false,"creators":["Whaits, Clive Vivian"],"institution":"Department of Electrical Engineering","degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":[],"advisors":["Braun, Robin"],"committee_chairs":[],"committee_members":[],"year":1997,"date_issued":"1997","date_published":"1997","updated_at":"2026-07-22T22:22:54Z","subjects":[],"languages":["eng"],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"http://hdl.handle.net/11427/9565","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.advisor","label":"Advisor","values":["Braun, Robin"]},{"key":"dc:creator","label":"Author","values":["Whaits, Clive Vivian"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2014-11-11T20:07:35Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2014-11-11T20:07:35Z"]},{"key":"dc:date.issued","label":"Date","values":["1997"]},{"key":"dc:publisher.department","label":"Dc Publisher Department","values":["Department of Electrical Engineering"]},{"key":"dc:publisher.institution","label":"Dc Publisher Institution","values":["University of Cape Town"]},{"key":"dc:type","label":"Dc Type","values":["Master Thesis"]},{"key":"dc:type.qualificationlevel","label":"Dc Type Qualificationlevel","values":["Masters"]},{"key":"dc:type.qualificationname","label":"Dc Type Qualificationname","values":["MSc"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language.iso","label":"Language (ISO)","values":["eng"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.uri","label":"Identifier URI","values":["http://hdl.handle.net/11427/9565"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Includes bibliographical references."]},{"key":"dc:description.abstract","label":"Abstract","values":["This thesis reports the research done into a relatively unknown modulation scheme called VPSK (Variable Phase Shift Keying) and the use of DSSS (Direct Sequence Spread Spectrum) techniques to achieve carrier synchronization and hence coherent demodulation in the receiver. VPSK is a new and relatively unknown modulation scheme in which data bits are encoded using patented algorithms designed by Millerand Walker. VPSK modulation is a SSBSC (Single Sideband Suppressed Carrier) modulation scheme with good bandwidth efficiency. Data is coherently demodulated in the receiver. In existing VPSK systems, the locally generated carrier in the receiver is synchronized to an integer multiple of the symbol clock frequency to allow coherent demodulation. 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This coherent method of demodulation is not optimum if the channel over which information must be transmitted is a non-Gaussian channel, or has multi-path characteristics."],"dc:identifier.uri":["http://hdl.handle.net/11427/9565"],"dc:language.iso":["eng"],"dc:publisher.department":["Department of Electrical Engineering"],"dc:publisher.institution":["University of Cape Town"],"dc:title":["Investigation into variable shift keying using direct sequence spread spectrum techniques"],"dc:type":["Master Thesis"],"dc:type.qualificationlevel":["Masters"],"dc:type.qualificationname":["MSc"]},"updated_at":"2026-07-22T22:22:54Z"}