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dc.contributorTampereen teknillinen yliopisto, Tietoliikennetekniikka
dc.creatorSiddiqui, Bashir Ahmed
dc.date.accessioned2010-07-06T11:13:12Z
dc.date.available2010-07-06T11:13:12Z
dc.date.issued2010-07-06T11:13:12Z
dc.identifier.urihttp://dspace.cc.tut.fi/dpub/handle/123456789/6688
dc.description.abstractAt the moment, Global Positioning System (GPS) is the only positioning system with global coverage. Currently, there are efforts to modernize GPS with the aim of improving its performance. Meanwhile, Europe is developing its own satellite positioning system, GALILEO. In order to provide interoperability with GPS and globally available navigational systems, new modulation techniques have been introduced. Multiplexed Binary-Offset-Carrier (MBOC) modulated signals are the main candidates for the future Galileo Open Services (OS) and modernized GPS L1C signals. Spreading waveforms corresponding to pilot and data components can be formed in a number of ways, including Composite Binary Offset Carrier (CBOC) and Time-Multiplexed Binary Offset Carrier (TMBOC). CBOC is considered here because CBOC has been selected for Galileo E1 OS signals in the most recent Galileo SIS-ICD of 2008. This new composition of E1 signal allows different techniques for acquiring the signal, i.e. data-only channel, pilot-only channel and joint data and pilot channel. The MBOC(6,1,1/11) power spectral density (PSD) has better performance than SinBOC(1,1) power spectral density because it is a mixture of BOC(1,1) spectrum and BOC(6,1) spectrum. MBOC modulation schemes also bring new challenges due to additional side lobes in the envelope of the Autocorrelation Function (ACF) compared with the traditional BPSK modulation used in the basic GPS signals, which make the signal acquisition process challenging. In order to deal with the side lobes, the steps ‘Δtbin’ for searching the time-bin search space should be chosen carefully. The goal of this thesis has been to develop an acquisition unit based on CBOC reference code and analyze the performance of new acquisition unit in terms of acquisition performance because MBOC signal has better power spectral density compared to SinBOC(1,1) signal. A brief study about the choice of the time-bin step ‘Δtbin’ for searching the time-frequency window has been studied. Three different strategies have been used to acquire the signal and results are presented for each approach. The switching architecture model has introduced in the transmitter part which operates at dual frequency are also addressed under the scope of this thesis. The simulations are carried out with an own developed Simulink model for Galileo OS E1 signals, based on the most recent Galileo Signal-in-Space Interface Control Documentation. Conclusions are drawn with respect to the performance deterioration of a reference SinBOC(1,1) receiver compared to a reference CBOC receiver, and also with respect to different techniques used for acquiring the signal. Comparisons between the infinite bandwidth (theoretical case, typically used in literature) and a limited front-end filter bandwidth of 3 MHz (double-sided bandwidth) are also made. The choice of significant detection threshold in order to detect the signal properly and the performance degradation of the CBOC reference receiver when using switching architecture model in terms of detection probability are also presented. /Kir10en
dc.format.extent78
dc.format.mimetypeapplication/pdf
dc.language.isoen
dc.rightsThis publication is copyrighted. You may download, display and print it for Your own personal use. Commercial use is prohibited.en
dc.titleSimulink-Based Acquisition Unit for Galileo E1 CBOC Modulated Signalsen
dc.identifier.urnURN:NBN:fi:tty-201007061245
dc.contributor.laitosTietoliikennetekniikka
dc.contributor.tiedekuntaTieto- ja sähkötekniikan tiedekunta
dc.contributor.yliopistoTampereen teknillinen yliopistofi
dc.programmeTietotekniikan koulutusohjelmaen
dc.date.published2010-04-07
dc.contributor.laitoskooditlt
dc.contributor.thesisadvisorLohan, Elena-Simona
dc.contributor.degreesupervisorLohan, Elena-Simona
dc.contributor.degreesupervisorSkournetou, Danai
dc.type.ontasotDiplomityö - Master's thesis


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