Tesi: "Carrier phases"

1

Cheng, Yuan-Chung Ph D. Massachusetts Institute of Technology. "Quantum dynamics in condensed phases : charge carrier mobility, decoherence, and excitation energy transfer". Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/34496.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Chemistry, 2006.
Vita.
Includes bibliographical references.
In this thesis, we develop analytical models for quantum systems and perform theoretical investigations on several dynamical processes in condensed phases. First, we study charge-carrier mobilities in organic molecular crystals, and develop a microscopic theory that describes both the coherent band-like and incoherent hopping transport observed in organic crystals. We investigate the structures of polaron states using a variational scheme, and calculate both band-like and hopping mobilities at a broad range of parameters. Our mobility calculations in 1-D nearest-neighbor systems predict universal band-like to hopping transitions, in agreement with experiments. Second, motivated by recent developments in quantum computing with solid-state systems, we propose an effective Hamiltonian approach to describe quantum dissipation and decoherence. We then applied this method to study the effect of noise in a number of quantum algorithms and calculate noise threshold for fault-tolerant quantum error corrections (QEC). In addition, we perform a systematic investigation on several variables that can affect the efficiency of the fault-tolerant QEC scheme, aiming to generate a generic picture on how to search for optimal circuit design for real physical implementations.
(cont.) Third, we investigate the quantum coherence in the B800 ring of' of the purple bacterium Rps. acidophila and how it affects the dynamics of excitation energy transfer in a single LH2 complex. Our calculations suggest that the coherence in the B800 ring plays a significant role in both spectral and dynamical properties. Finally, we discussed the validity of Markovian master equations, and propose a concatenation scheme for applying Markovian master equations that absorbs the non-Markovian effects at short times in a natural manner. Applications of the concatenation scheme on the spin-boson problem show excellent agreements with the results obtained from the non-Markovian master equation at all parameter range studied.
by Yuan-Chung Cheng.
Ph.D.

2

Henkel, Patrick [Verfasser]. "Reliable Carrier Phase Positioning / Patrick Henkel". München : Verlag Dr. Hut, 2010. http://d-nb.info/1009972383/34.

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3

Li, Kuangmin. "Enhanced Distance Measuring Equipment Carrier Phase". Ohio University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1416581585.

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4

Bruggemann, Troy S. "GPS L1 Carrier Phase Navigation Processing". Thesis, Queensland University of Technology, 2005. https://eprints.qut.edu.au/16122/1/Troy_Bruggermann_Thesis.pdf.

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In early 2002, Queensland University of Technology (QUT) commenced to develop its own low-cost Global Positioning System (GPS) receiver with the capability for space applications such as satellites in Low Earth Orbits, and sounding rockets. This is named the SPace Applications Receiver (SPARx). This receiver development is based on the Zarlink (formerly known as Mitel) GP2000 Chip set and is a modification of the Mitel Orion 12 channel receiver design. Commercially available GPS receivers for space applications are few and expensive. The QUT SPARx based on the Mitel Orion GPS receiver design is cost effective for space applications. At QUT its use is being maximized for space applications and carrier phase processing in a cost-effective and specific way. To build upon previous SPARx software developments made from 2002 to 2003, the receiver is required to be modified to have L1 carrier phase navigation capability. Such an improvement is necessary for the receiver to be used in 3-axis attitude determination and relative navigation using carrier phase. The focus of this research is on the implementation of the L1 carrier phase measurement capability with SPARx. This is to enable the use of improved navigation algorithms. Specific emphasis is given to the areas of time synchronization, the carrier phase implementation and carrier phase differential GPS with SPARx. Test results conducted in the area of time synchronization and comparisons with other carrier phase capable GPS receivers are given, as well as an investigation of the use of SPARx in carrier phase differential GPS. Following these, conclusions and recommendations are given for further improvements to SPARx.

5

Bruggemann, Troy S. "GPS L1 Carrier Phase Navigation Processing". Queensland University of Technology, 2005. http://eprints.qut.edu.au/16122/.

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In early 2002, Queensland University of Technology (QUT) commenced to develop its own low-cost Global Positioning System (GPS) receiver with the capability for space applications such as satellites in Low Earth Orbits, and sounding rockets. This is named the SPace Applications Receiver (SPARx). This receiver development is based on the Zarlink (formerly known as Mitel) GP2000 Chip set and is a modification of the Mitel Orion 12 channel receiver design. Commercially available GPS receivers for space applications are few and expensive. The QUT SPARx based on the Mitel Orion GPS receiver design is cost effective for space applications. At QUT its use is being maximized for space applications and carrier phase processing in a cost-effective and specific way. To build upon previous SPARx software developments made from 2002 to 2003, the receiver is required to be modified to have L1 carrier phase navigation capability. Such an improvement is necessary for the receiver to be used in 3-axis attitude determination and relative navigation using carrier phase. The focus of this research is on the implementation of the L1 carrier phase measurement capability with SPARx. This is to enable the use of improved navigation algorithms. Specific emphasis is given to the areas of time synchronization, the carrier phase implementation and carrier phase differential GPS with SPARx. Test results conducted in the area of time synchronization and comparisons with other carrier phase capable GPS receivers are given, as well as an investigation of the use of SPARx in carrier phase differential GPS. Following these, conclusions and recommendations are given for further improvements to SPARx.

6

Ilunga, Ngoy Serge. "Impact des termites sur les cycles biogéochimiques du cuivre et du cobalt dans le Katanga (RDC) - Application à la prospection minière". Electronic Thesis or Diss., Université de Lorraine, 2022. https://docnum.univ-lorraine.fr/ulprive/DDOC_T_2022_0207_ILUNGA_NGOY.pdf.

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La compréhension de l'apport du rôle des termites sur le transport des métaux d'intérêt économique au sein de l'ensemble lithosphère - pédosphère - termitières, se révèle d'un grand intérêt pour une caractérisation géochimique et géologique d'anomalies en prospection minière. En effet, les termites jouent un rôle fonctionnel remarquable dans la structuration des sols, entrainant des enrichissements chimiques liés au transport vertical de minéraux, échangés entre les horizons situés en profondeur et les termitières érigées en surface. Cette thèse a pour objectif de mettre en lumière l'impact des termites sur les cycles biogéochimiques du Cu et du Co dans une région potentiellement riche en ressources minérales (Katanga, RDC), dans un objectif d'utilisation optimisée des termitières en prospection minière. Cette objectif requiert une caractérisation des phases minérales et organiques à diverses échelles. Pour y parvenir, il a été question en premier lieu, de faire une cartographie géochimique des termitières de deux genres dominants de la région, Macrotermes et Cubitermes, à l'échelle paysagère sur une zone ayant fait l'objet d'une cartographie géologique et géochimique sur sols et roches. Cette cartographie a permis de mettre en évidence à l'échelle régionale des faciès lithogéochimiques traduisant la géologie des formations sous-jacentes et ce en fonction des habitudes alimentaires de chaque genre de termite. La distribution spatiale des termitières a également permis de suivre l'évolution des teneurs en Cu et Co au sein des termitières en fonction de la géologie de la zone d'étude. La combinaison des données acquises sur la constitution minéralogique et géochimique des matériaux constituant les termitières de Macrotermes falciger et la caractérisation morphologique et chimique de leurs principaux constituants à l'échelle microscopique a permis l'identification des phases porteuses des métaux d'intérêts dans les matériaux de ces termitières. De même la comparaison de la signature géochimique des termitières de M. falciger et de leurs matériels parentaux a permis d'établir un lien lithogéochimique, identifiant ainsi la source d'approvisionnement en profondeur utilisée par les individus de M. falciger. Enfin, la conjugaison de résultats d'une part sur la caractérisation géochimique de quatre fractions granulométriques (0-20 µm ; 20-63 µm ; 63-200 µm ; 200-2000 µm) des termitières et d'autre part sur l'évaluation de l'impact des termites sur la constitution d'agrégats dans les termitières et/ou sols, a permis de préciser les fractions granulométriques les plus informatives sur la présence et la minéralisation des phases porteuses des métaux d'intérêt du Katanga dans les matériaux de termitières. L'application de toutes ces méthodes et tous les éléments recueillis ont permis de proposer un schéma des cycles biogéochimiques de Cu et Co dans ce système soulignant l'utilisation des termitières en prospection minière efficace et efficiente
Knowledge of the influence of termites on transport of metals of economic interest within the complex of lithosphere, pedosphere and termite mounds is of great interest for geochemical and geological characterization of anomalies in mining prospection. Termites have an important functional role in the structuring of soils, causing chemical enrichment through the vertical transport of minerals exchanged between the deeper horizons and the termite mounds built at the surface. Our objective in this thesis is to evaluate the influence of termites on Cu and Co biogeochemical cycles in a mineral-rich region (Katanga, DRC), with the aim to optimize the utilization of termite mounds in mining prospection. This objective requires a characterization of mineral and organic phases at various scales. To achieve this, firstly, a geochemical mapping of termite mounds of two dominant genera of the region, Macrotermes and Cubitermes, was carried out at the landscape scale in an area that received a geological and soil and rock geochemical mapping. The utilization of termite mounds allowed the identification of lithogeochemical facies reflecting the subjacent geology on a regional scale according to the feeding habits of each termite genus. The spatial distribution of termite mounds also allowed us to follow Cu and Co content evolution according to study area geology. The combination of mineralogical and geochemical data acquired on Macrotermes falciger termite mounds and morphological and chemical characterization of their main constituents at microscopic scale allowed to identify carrier phases of interest metals in termite mounds materials. Similarly, the comparison of geochemical signatures of M. falciger termite mounds and their parent materials allowed to establish a lithogeochemical relationship, identifying the source of provisioning at depth by M. falciger. Finally, the association of geochemical characterization results of termite mounds for four granulometric fractions (0-20 µm; 20-63 µm; 63-200 µm; 200-2000 µm) and results on evaluation of the impact of termites on the constitution of aggregates in termite mounds and/or soils, allowed to specify the most informative granulometric fractions on the presence and mineralization of carrier phases of interest metals in Katanga in termite mound materials. The application of all these methods and all elements collected allowed us to propose a Cu and Co biogeochemical cycle scheme in this system, underlying the use of termite mounds in effective and efficient mining prospection

7

Wan, Yinhua. "Fractional biological macromolecules using carrier phase ultrafiltration". Thesis, University of Oxford, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.409749.

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8

Hunzinger, Jason F. "Robust precision navigation using carrier-phase differential GPS". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ29600.pdf.

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9

Varner, Christopher Champion. "DGPS carrier phase networks and partial derivative algorithms". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape3/PQDD_0027/NQ49546.pdf.

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10

Burmeister, William J. "The analysis and design of a costas phase locked loop for the acquisition of carrier phase of suppressed carrier communication systems". Honors in the Major Thesis, University of Central Florida, 1991. http://digital.library.ucf.edu/cdm/ref/collection/ETH/id/1.

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This item is only available in print in the UCF Libraries. If this is your Honors Thesis, you can help us make it available online for use by researchers around the world by following the instructions on the distribution consent form at http://library.ucf.edu/Systems/DigitalInitiatives/DigitalCollections/InternetDistributionConsentAgreementForm.pdf You may also contact the project coordinator, Kerri Bottorff, at kerri.bottorff@ucf.edu for more information.
Bachelors
Engineering
Electrial Engineering

11

Zhang, Yan. "Carrier phase and frequency estimation for burst-mode communications". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/MQ59311.pdf.

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12

Smyrnaios, Marios [Verfasser]. "Carrier-phase multipath in satellite-based positioning / Marios Smyrnaios". Hannover : Technische Informationsbibliothek (TIB), 2016. http://d-nb.info/1107605806/34.

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13

Fohlmeister, Friederike [Verfasser]. "GNSS Carrier Phase Tracking under Ionospheric Scintillations / Friederike Fohlmeister". Düren : Shaker, 2021. http://d-nb.info/1233548255/34.

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14

Wang, Lei. "Reliability control of GNSS carrier-phase integer ambiguity resolution". Thesis, Queensland University of Technology, 2015. https://eprints.qut.edu.au/86976/1/Lei_Wang_Thesis.pdf.

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This research investigates how to obtain accurate and reliable positioning results with global navigation satellite systems (GNSS). The work provides a theoretical framework for reliability control in GNSS carrier phase ambiguity resolution, which is the key technique for precise GNSS positioning in centimetre levels. The proposed approach includes identification and exclusion procedures of unreliable solutions and hypothesis tests, allowing the reliability of solutions to be controlled in the aspects of mathematical models, integer estimation and ambiguity acceptance tests. Extensive experimental results with both simulation and observed data sets effectively demonstrate the reliability performance characteristics based on the proposed theoretical framework and procedures.

15

Moon, Eric Wayne. "Carrier-envelope phase stabilization of grating-based chirped-pulse amplifiers". Diss., Manhattan, Kan. : Kansas State University, 2009. http://hdl.handle.net/2097/1125.

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16

Gabor, Michael Joseph. "GPS carrier phase ambiguity resolution using satellite-satellite single differences /". Digital version accessible at:, 1999. http://wwwlib.umi.com/cr/utexas/main.

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17

Zhu, Feng. "Carrier envelope phase stabilization of a femtosecond laser and iodine spectroscopy". Texas A&M University, 2005. http://hdl.handle.net/1969.1/4274.

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The carrier envelope (CE) phase of a femtosecond laser was stabilized. The laser produces an ultra stable comb of frequency spanning the visible region and basically is an optical frequency synthesizer and ready for the frequency domain applications. In this context, the CW stability of the Ti:sapphire laser is discussed to provide a procedure for the femtosecond laser adjustments. In addition, the pulse trains emitted by the femtosecond laser are described analytically to provide a theoretical basis for carrier envelope phase stabilization. An f to 2f interferometer was used to detect the carrier envelope offset frequency, and a fast photo diode was employed to measure the repetition rate. Two similar designed phase lock loops are used to stabilize both the carrier envelope offset frequency and the repetition rate to the respective reference frequencies. The stability reaches 100mHz for the carrier envelope offset frequency and 10mHz for the repetition rate for a period of up to an hour. Doppler free iodine saturation spectroscopy was set up to provide a precise frequency reference to which a CW dye laser can be locked on. The near future goal is to accurately measure this frequency stabilized dye laser with the optical frequency synthesizer.

18

Ortega, Zafra Sebastian Joel. "Circular Modulation Formats and Carrier Phase Estimation for Coherent Optical Systems". Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-177439.

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Digital coherent receivers stand today as a promising technology for the next generation of high-capacity optical systems. Coherent systems enable the use of multilevel modulation formats which increase the spectral efficiency of a system. Key challenges of multilevel coherent systems are the strict laser linewidth requirements and receiver complexity which prevent a cost-effective implementation. The goal of this thesis is to address these challenges by investigating a novel approach to implement phase noise tolerant optical systems. The performance of a phase recovery scheme, normalized Viterbi-Viterbi carrier phase estimation (V-V CPE), is investigated for circular m-level quadrature amplitude modulation (C-mQAM) signals. C-mQAM provides inherent characteristics for phase noise mitigation, while V-V CPE enables an efficient hardware implementation in a blind feed-forward receiver. A coherent C-mQAM system was simulated in VPItransmissionMaker with phase recovery implemented with MATLAB. Phase noise tolerance was analyzed for C-16QAM and C-64QAM signals. Results show an enhanced phase noise tolerance at a low sensitivity penalty. The achieved linewidth tolerance shows an enhanced performance over available CPE schemes for square mQAM signals, and enables the use of cost-effective lasers. C-mQAM signals allow a straightforward employment of V-V CPE, which can be easily upgraded for higher order circular modulations without adding significant complexity. By combining the power of normalized V-V CPE with C-mQAM inherent characteristics, the phase noise tolerance is enhanced with an efficient implementation. These results show that C-mQAM implemented with V-V CPE is a viable and promising alternative for phase noise tolerant high-speed optical coherent systems.

19

Liao, Xiangqian. "Carrier phase-based ionosphere recovery over a regional area GPS network". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/MQ65000.pdf.

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20

Lücking, Fabian. "Carrier-envelope phase control for the advancement of attosecond pulse generation". Diss., Ludwig-Maximilians-Universität München, 2014. http://nbn-resolving.de/urn:nbn:de:bvb:19-173074.

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When the optical pulses emitted by a laser become so short in time that they encompass only a few cycles of the carrier wave, the phase between carrier and envelope becomes a crucial parameter. The ability to control this carrier-envelope phase (CEP) is elemental to experiments probing the fastest processes in the microcosm, occurring on the time-scale of attoseconds. More than a decade into the attosecond era, the limitations of the established CEP stabilisation technique have begun to curtail experimental progress. First, increasingly complex experiments require many hours of uninterrupted operation at the same waveform. Second, the pulses used in experiments are approaching the single-cycle boundary, calling for ever-decreasing CEP noise. With the conventional stabilisation technique, already these two requirements cannot be fulfilled simultaneously. Ultimately, the low efficiency of the underlying nonlinear processes can only be compensated by driver lasers at a higher repetition rate than available at present. In order to advance attosecond pulse generation, novel approaches to CEP control thus face a threefold challenge that outlines this thesis: To simultaneously provide low CEP noise and long-term operation to present-day few-cycle lasers and amplifiers, and to investigate CEP control capability in high average power sources that are currently under development. This thesis describes the adaptation of cavity-external CEP stabilisation for use with few-cycle pulses. The intrinsic limitations of the conventional feed-back technique are lifted. A laser oscillator is demonstrated to maintain record-low CEP noise for tens of hours of operation free from phase discontinuities. In addition, a modification of the technique is presented that further enhances the applicability to amplified systems. Two routes are investigated to achieve CEP control in system architectures that represent potential megahertz repetition rate driver sources. In combination with temporal pulse compression, a thin-disk laser is shown to yield few-cycle pulses. Experiments are presented that provide the groundwork towards the first CEP-stabilised thin-disk oscillator. The second approach targets the seed oscillator of a fibre chirped-pulse amplifier. The CEP noise properties of different amplification regimes are examined. Intensity enhancement of the output pulses in a passive resonator is shown to benefit greatly even from a coarse lock of the CEP slip rate. For few-cycle pulse energy to reach the millijoule level and above, amplification and temporal compression will remain indispensable in the foreseeable future. Maintaining CEP stability across such stages is crucial, irrespective of the technology employed. Cavity-external CEP control is demonstrated to enable more than 24 hours of constant-CEP operation in chirped-pulse amplifiers. Furthermore, a novel actuator is introduced that, in conjunction with a fast means of measuring the CEP, is able to provide phase correction of the amplified waveform up to several kilohertz bandwidth. The result is a train of millijoule-level pulses with residual CEP noise comparable to that of state-of-the-art nanojoule oscillators. Eventually, an experiment is presented to examine the influence of different types of hollow-core fibre-based temporal compression on the CEP. The findings shed new light on the origin of adverse effects introduced by this technique, and point out ways towards effective compensation.
Wenn die von einem Laser emittierten Lichtpulse so kurz werden, dass ihre Dauer nur noch wenige Schwingungszyklen des elektrischen Feldes umfasst, kommt der Phase zwischen Trägerwelle und Einhüllender (CEP) eine entscheidende Rolle zu. Ihre Regelung ist essentiell für jene Experimente, die die schnellsten Prozesse in der Natur auf der Zeitskala von Attosekunden ausloten. Mehr als zehn Jahre nach Beginn der Attosekunden-Ära ist die etablierte Methode der CEP-Regelung zum Hindernis für experimentelle Fortschritte geworden. Einerseits erfordern immer komplexere Experimente, dass das elektrische Feld der Pulse über viele Stunden konstant bleibt. Andererseits zeichnet sich eine Entwicklung der Pulsdauer zu immer kürzerer Dauer in Richtung eines einzigen Zyklus ab, was eine steigende Präzision der Regelung erfordert. Die gleichzeitige Erfüllung schon dieser beiden Anforderungen ist mit der konventionellen Methode nicht zu erreichen. Schlussendlich kann die niedrige Effizienz der zugrunde liegenden nichtlinearen Prozesse nur die Verwendung von Lasersystemen mit deutlich erhöhter Wiederholrate ausgeglichen werden. Um die Erzeugung von Attosekunden-Pulsen voranzutreiben, müssen neue Ansätze zur CEP-Regelung einer dreifachen Herausforderung gerecht werden, die dieser Dissertation ihren Rahmen gibt: Einerseits hohe Präzision und andererseits hohe Langzeittauglichkeit zur Verfügung zu stellen, und überdies neue Wege zur CEP-Regelung von derzeit in Entwicklung befindlichen Laserquellen mit hoher Durchschnittsleistung aufzuzeigen. Diese Dissertation beschreibt die Anpassung einer alternativen Methode der CEP-Regelung auf Pulse mit einer Dauer von wenigen Zyklen. Die intrinsischen Beschränkungen der konventionellen Technik werden damit behoben. Der solchermaßen stabilisierte Oszillator bietet geringstes CEP-Rauschen über mehrere zehn Stunden Laufzeit ohne Phasensprünge. Zusätzlich wird eine Abwandlung der Methode beschreiben, die deren Anwendbarkeit für Verstärkersysteme erweitert. Die CEP-Regelung in Systemarchitekturen für hohe Durchschnittsleistungen wird an zwei Lasersystemen untersucht, die exemplarisch für potentielle Attosekunden-Quellen mit Megahertz-Wiederholrate stehen. Es wird gezeigt, dass ein Scheibenlaser in Kombination mit zeitlicher Pulskompression genutzt werden kann, um Pulse in der Größenordnung von 10 fs zu erzeugen. Erste Experimente zu deren CEP-Stabilisierung ebnen den Weg für den ersten CEP-stabilen Scheibenlaser. Der zweite Ansatz betrifft die CEP-Regelung eines Oszillator-Verstärker-Systems. Das CEP-Rauschverhalten verschiedener Faserverstärker wird untersucht. Es wird gezeigt, dass die Überhöhung des Pulszugs in einem passiven Resonator auch von einer groben Stabilisierung der CEP-Änderungsrate deutlich profitiert. Um Pulse von wenigen Zyklen Dauer auf eine Energie von Millijoule und darüber hinaus zu bringen, wird Verstärkung und zeitliche Kompression auf absehbare Zeit unverzichtbar bleiben. Unabhängig von der hierzu gewählten Technologie ist es von entscheidender Bedeutung, den Einfluss dieser Prozesse auf die CEP gering zu halten. Die Verwendung eines mit der alternativen CEP-Regelung ausgestatteten Oszillators zur zeitlich gestreckten Verstärkung wird beschrieben, was in hochenergetischen Pulsen mit über 24 Stunden konstanter Wellenform resultiert. Alsdann wird ein neuartiger CEP-Aktuator beschrieben, der in Kombination mit einer schnellen Messmethode die CEP-Korrektur eines jeden Pulses bei einer Bandbreite von mehreren Kilohertz leistet. Das Resultat ist ein Pulszug auf Millijoule-Niveau, dessen CEP-Rauschen mit dem eines Nanojoule-Oszillators vergleichbar ist. Abschließend wird ein Experiment vorgestellt, mit dem der Einfluss von Hohlfaser-Kompression auf die CEP untersucht wird. Die Ergebnisse werfen neues Licht auf den Ursprung zusätzlichen Rauschens in solchen Aufbauten, und zeigen Wege zu dessen Vermeidung auf.

21

Wong, Ronald T. M. "GPS carrier phase multipath mitigation by spectral analysis for LEO satellite". Thesis, University of Surrey, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.402808.

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22

Achanta, Raghavendra. "Detection and Correction of Global Positioning System Carrier Phase Measurement Anomalies". Ohio University / OhioLINK, 2004. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1089745184.

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23

Huang, Jidong. "A HIGH-INTEGRITY CARRIER PHASE BATCH PROCESSOR FOR DIFFERENTIAL SATELLITE POSITIONING". Ohio University / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1196143814.

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24

Byun, Sung Hun. "Satellite orbit determination using GPS carrier phase in pure kinematic mode /". Digital version accessible at:, 1998. http://wwwlib.umi.com/cr/utexas/main.

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25

Achanta, Raghavendra. "Detection and correction of global positional system carrier phase measurement anomalies". Ohio : Ohio University, 2004. http://www.ohiolink.edu/etd/view.cgi?ohiou1089745184.

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26

Borchers, Bastian. "Pushing frontiers in Carrier-Envelope Phase stabilization of ultrashort laser pulses". Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät, 2015. http://dx.doi.org/10.18452/17137.

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Die vorliegende Arbeit ist der Verbesserung der Carrier-Envelope Phasenstabilisierung von ultrakurzen Laserimpulsen gewidmet. Zur Realisierung von Fortschritten auf diesem Gebiet werden die grundlegenden Rauschquellen identifiziert, die das erzielbare Restphasenrauschen limitieren, und geeignete Maßnahmen zu deren Verringerung vorgeschlagen. Es wird gezeigt, dass sowohl die Messung der Carrier-Envelope Phase (CEP) als auch deren Kontrolle durch verschiedene Rauschbeiträge beeinträchtigt wird. Der Detektionsprozess ist dabei einerseits durch technische Rauschquellen beeinflusst, die vor allem in den verwendeten nichtlinearen Interferometern auftreten. Andererseits repräsentiert das Detektionsrauschen während der elektro-optischen Wandlung eine fundamentale Limitierung, da das optische Schrotrauschen sowie das Rauschen des Lichtdetektors die Messung der CEP unausweichlich beeinträchtigen. Es wird demonstriert, wie solche Beschränkungen durch geeignete Wahl der Interferometertopologie, bzw. durch Optimierung des spektralen Verbreiterungsmechanismus verringert werden können. Experimentell gelingt es dadurch den Signal-Rauschabstand der Phasenmessung um 20 Dezibel zu steigern. Hinsichtlich der CEP Kontrolle von Oszillatoren wird in dieser Arbeit ein neuartiges Doppelstabilisierungskonzept vorgestellt, welches eine feed-forward Stabilisierung, die auf einem akustooptischen Frequenzschieber beruht, mit einer klassischen Feedback Regelung kombinert. Mit diesem Konzept gelingt eine Reduzierung des Phasenrestrauschen auf beispiellose 20 Milliradian. Darüber hinaus werden weitere neue Stabilisierungskonzepte vorgestellt, die ohne Feedback zu dem Laseroszillator auskommen. Bei einem dieser Konzepte, handelt es sich um eine gepulste feed-forward Stabilisierung, die speziell für das Zusammenwirken mit einer Verstärkerstufe konzipiert ist. Erste experimentelle Ergebnisse zeigen, dass Phasenrestrauschen von weniger als 100 Milliradian auch für Verstärkersysteme erreichbar sind.
The present thesis is dedicated to improvements of the carrier-envelope phase stabilization of ultrashort laser pulses. In order to realize such improvements, the fundamental noise sources are identified, and suitable measures for their reduction are proposed. It is shown that both, the measurement of the carrier-envelope phase (CEP) as well as its control are corrupted by different noise contributions. On the one hand, the detection process is influenced by technical noise sources, which arise especially in the used nonlinear interferometers. On the other hand, the detection noise in the electro-optic conversion represents a fundamental limitation, since the optical shot noise as well as the noise induced by the light detector inevitably influence the measurement of the CEP. It is demonstrated how such limitations can be minimized by a suitable choice of the interferometer topology and by an optimization of the spectral broadening process in a micro-structured fiber. This way an enormous improvement of the signal-to-noise ratio by 20 dB is obtained experimentally, which significantly reduces the limitation of detection noise. For controlling the CEP of mode-locked oscillators, a novel double stabilization scheme is introduced in this thesis, which combines a feed-forward stabilization based on an acousto-optic frequency shifter, with a classical feedback loop. This method enables a reduction of the residual phase jitter to an unprecedented value of 20 milliradian. Beyond that, several further concepts are introduced that are capable of stabilizing the CEP without any feedback to the laser oscillator. One of these concepts, represents a pulsed feed-forward stabilization, which is specifically designed for the use in combination with a subsequent amplification stage. First experimental results indicate that residual phase jitters of less than 100 milliradian are within reach also for amplified laser systems.

27

Stewart, Peter John. "The reduction of differential ionospheric delay for GPS carrier phase ambiguity resolution". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp04/mq23840.pdf.

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28

Mai, Wilson W. Q. "Timing and carrier phase recovery for a burst ATM satellite TDMA channel". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0002/MQ45286.pdf.

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29

Luo, Ning. "Precise relative positioning of multiple moving platforms using GPS carrier phase observables". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/nq64825.pdf.

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30

Lee, Shane-Woei. "A carrier phase only processing technique for differential satellite-based positioning systems". Ohio : Ohio University, 1999. http://www.ohiolink.edu/etd/view.cgi?ohiou1181175000.

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31

Wellons, William Lee. "A shipboard global positioning system carrier phase interferometric aircraft flight reference system". Ohio : Ohio University, 1994. http://www.ohiolink.edu/etd/view.cgi?ohiou1179860957.

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32

Tritschler, Thorsten [Verfasser]. "Extreme Nonlinear Optics and Carrier-Envelope Phase Effects in Semiconductors / Thorsten Tritschler". Aachen : Shaker, 2005. http://d-nb.info/1181610915/34.

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33

Burgess, George, e William Murphy. "CARRIER PHASE MODULATION USING DIRECT DIGITAL SYNTHESIS FOR AN S-BAND UPLINK". International Foundation for Telemetering, 1991. http://hdl.handle.net/10150/613115.

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International Telemetering Conference Proceedings / November 04-07, 1991 / Riviera Hotel and Convention Center, Las Vegas, Nevada
Phase modulation has traditionally been performed in analog hardware. A new product will be described that implements this function using a phase-modulating NCO IC. The modulating signal is sampled and added digitally to the phase of the carrier generated by the NCO. This method produces an output spectrum with highly accurate modulation control, low spur levels and minimal distortion. The effects of generating sampled phase-modulated signals will be described. The selection of the clock and output frequencies are critical to ensuring a clean spectrum. Resulting output spectra are shown.

34

Tsujii, Toshiaki. "Precise Determination of Aircraft Position and Attitude Using GPS Carrier Phase Measurement". Kyoto University, 1998. http://hdl.handle.net/2433/157046.

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本文データは平成22年度国立国会図書館の学位論文(博士)のデジタル化実施により作成された画像ファイルを基にpdf変換したものである
Kyoto University (京都大学)
0048
新制・論文博士
博士(工学)
乙第9890号
論工博第3354号
新制||工||1120(附属図書館)
UT51-98-N124
(主査)教授藪下信, 教授片山徹, 教授足立紀彦
学位規則第4条第2項該当

35

Xu, Tianhua. "DSP based Chromatic Dispersion Equalization and Carrier Phase Estimation in High Speed Coherent Optical Transmission Systems". Doctoral thesis, KTH, Optik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-94835.

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Coherent detection employing multilevel modulation formats has become one of the most promising technologies for next generation high speed transmission systems due to the high power and spectral efficiencies. Using the powerful digital signal processing (DSP), coherent optical receivers allow the significant equalization of chromatic dispersion (CD), polarization mode dispersion (PMD), phase noise (PN) and nonlinear effects in the electrical domain. Recently, the realizations of these DSP algorithms for mitigating the channel distortions in the coherent transmission systems are the most attractive investigations. The CD equalization can be performed by the digital filters developed in the time and the frequency domain, which can suppress the fiber dispersion effectively. The PMD compensation is usually performed in the time domain with the adaptive least mean square (LMS) and constant modulus algorithms (CMA) equalization. Feed-forward and feed-back carrier phase estimation (CPE) algorithms are employed to mitigate the phase noise (PN) from the transmitter (TX) and the local oscillator (LO) lasers. The fiber nonlinearities are compensated by using the digital backward propagation methods based on solving the nonlinear Schrödinger (NLS) equation and the Manakov equation. In this dissertation, we present a comparative analysis of three digital filters for chromatic dispersion compensation, a comparative evaluation of different carrier phase estimation methods considering digital equalization enhanced phase noise (EEPN) and a brief discussion for PMD adaptive equalization. To implement these investigations, a 112-Gbit/s non-return-to-zero polarization division multiplexed quadrature phase shift keying (NRZ-PDM-QPSK) coherent transmission system with post-compensation of dispersion is realized in the VPI simulation platform. In the coherent transmission system, these CD equalizers have been compared by evaluating their applicability for different fiber lengths, their usability for dispersion perturbations and their computational complexity. The carrier phase estimation using the one-tap normalized LMS (NLMS) filter, the differential detection, the block-average (BA) algorithm and the Viterbi-Viterbi (VV) algorithm is evaluated, and the analytical predictions are compared to the numerical simulations. Meanwhile, the phase noise mitigation using the radio frequency (RF) pilot tone is also investigated in a 56-Gbit/s NRZ single polarization QPSK (NRZ-SP-QPSK) coherent transmission system with post-compensation of chromatic dispersion. Besides, a 56-Gbit/s NRZ-SP-QPSK coherent transmission system with CD pre-distortion is also implemented to analyze the influence of equalization enhanced phase noise in more detail.
QC 20120528

36

Kakkar, Aditya. "Frequency Noise in Coherent Optical Systems: Impact and Mitigation Methods". Doctoral thesis, KTH, Optik och Fotonik, OFO, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-207072.

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The increase in capacity demand along with the advancement in digital signal processing (DSP) have recently revived the interest in coherent optical communications and led to its commercialization. However, design and development of robust DSP algorithms for example for carrier phase recovery (CPR) becomes complex as we opt for high order modulation formats such as 16QAM and beyond. Further, electrical-domain dispersion compensation (EDC), while providing many advantages, makes the system more susceptible to laser frequency noise (FN). For instance, in coherent optical links with post-reception EDC, while the transmitter frequency noise causes only phase impairment, the local oscillator (LO) FN in these systems results in a noise enhancement in both amplitude and phase. This noise is commonly known as equalization enhanced phase noise (EEPN). It results in asymmetric requirements for transmitter laser and LO laser. Further, the system design in the presence of lasers with non-white frequency noise becomes increasingly challenging for increased capacity-distance product. The main contributions of this thesis are, firstly, an experimentally validated theory of coherent optical links with lasers having general non-white frequency noise spectrum and corresponding system/laser design criteria and mitigation technique. Secondly, low complexity and high phase noise tolerant CPR for high order modulation formats. The general theory propounded in this thesis elucidates the origin of the laser frequency noise induced noise enhancement in coherent optical links with different DSP configurations. The thesis establishes the existence of multiple frequency noise regimes and shows that each regime results in different set of impairments. The influence of the impairments due to some regimes can ideally be reduced by optimizing the corresponding mitigation algorithms, while other regimes cause irretrievable impairments. Experimentally validated theoretical boundaries of these regimes and corresponding criteria applicable to system/laser design are provided. Further, an EEPN mitigation method and its two possible implementations are proposed and discussed. The thesis also demonstrates an intrinsic limitation of the conventional Blind Phase Search (BPS) algorithm due to angular quantization and provides methods to overcome it. Finally, this thesis proposes and demonstrates single stage and multi-stage carrier phase recovery algorithms for compensation of phase impairments due to the two lasers for higher order circular and square modulations. The proposed methods outperform the state of art algorithms both in performance and in complexity.

QC 20170516

European project ICONE gr. #608099

37

Hordeski, Theodore J. "Digital FSK/AM/PM Sub-Carrier Modulator on a 6U-VME-Card". International Foundation for Telemetering, 1996. http://hdl.handle.net/10150/611475.

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International Telemetering Conference Proceedings / October 28-31, 1996 / Town and Country Hotel and Convention Center, San Diego, California
Aerospace Report No. TOR-0059(6110-01)-3, section 1.3.3 outlines the design and performance requirements of SGLS (Space Ground Link Subsystem) uplink services equipment. This modulation system finds application in the U.S. Air Force satellite uplink commanding system. The SGLS signal generator is specified as an FSK (Frequency Shift Keyed)/AM (Amplitude Modulation)/PM (Phase Modulation) sub-carrier modulator. GDP Space Systems has implemented, on a single 6U-VME card, a SGLS signal generator. The modulator accepts data from several possible sources and uses the data to key one of three FSK tone frequencies. This ternary FSK signal is amplitude modulated by a synchronized triangle wave running at one half the data rate. The FSK/AM signal is then used to phase modulate a tunable HF (High-Frequency) sub-carrier. A digital design approach and the availability of integrated circuits with a high level of functionality enabled the realization of a SGLS signal generator on a single VME card. An analog implementation would have required up to three rack-mounted units to generate the same signal. The digital design improve performance, economy and reliability over analog approaches. This paper describes the advantages of a digital FSK/AM/PM modulation method, as well as DDS (Direct Digital Synthesis) and digital phase-lock techniques.

38

Fotopoulos, Georgia. "Parameterization of DGPS carrier phase errors over a regional network of reference stations". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0016/MQ55260.pdf.

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39

Lui, Gee L., e Kuang Tsai. "DATA-AIDED SYMBOL TIME AND CARRIER PHASE TRACKING FOR PRE-CODED CPM SIGNALS". International Foundation for Telemetering, 1999. http://hdl.handle.net/10150/608733.

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International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada
A data-aided approach to symbol time and carrier phase synchronization applicable to general continuous phase modulation (CPM) signals with modulation index 0.5 is described. Simulated BER performance of two receivers equipped with these synchronizers is presented for a GMSK BT=1/5 signal received in noise with constant and dynamic synchronization errors. Results demonstrate that these synchronizers provide a very promising and yet simple solution to the tracking problem in the design of coherent CPM receivers.

40

Brack, Andreas [Verfasser]. "Partial Carrier-Phase Integer Ambiguity Resolution for High Accuracy GNSS Positioning / Andreas Brack". München : Verlag Dr. Hut, 2019. http://d-nb.info/1200755448/34.

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41

Thorin, Emil. "Towards the carrier-envelope phase stabilization of a16 TW 4.5 fs laser system". Thesis, Umeå universitet, Institutionen för fysik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-152443.

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In the last decades the scientific development has made it possible to produce pulses with durations below the femtosecond time scale (1 fs = 1015 s), reaching to attoseconds (1 as = 1018 s). This is the time scale of electronic motion inside atoms and molecules. One way to produce isolated attosecond pulses is through high harmonic generation in gases with intense few-cycle laser pulses. This process depends strongly on the electric field shape relative to the pulse envelope, which is characterized by the so called carrier-envelope phase (CEP).The goal of this master’s thesis is to measure and investigate the possibility to improve the CEP stability of sub-two-cycle laser pulses from the laser, Light Wave Synthesizer 20 (LWS-20). The first step of the master’s thesis was to modify a Labview program used to evaluate the CEP change to be able to reevaluate the already acquired raw data. The measurements are done with an f-to-2f interferometer, whichis a spectral interference device, which measures the CEP difference between two pulses. The CEP change of the laser system was measured at three positions: after the multi-pass amplifier of the laser front end (MP), after a hollow-core fiber (HCF), which is used for spectral broadening, and at the end of the laser system. The stability is determined as the RMS error (standard deviation) of the phase change overall shots in one sample (lower RMS is better stability). The measurements show an average stability of 160±20 mrad RMS after the MP, 280±31 mrad RMS after the HCF and 560±53 mrad RMS at the end of the system. The stability at the end of the system could be improved to 475±40 mrad RMS after a scan of the pump energy for one of the amplifier stages. The HCF appears to provide a lower limit in stability and influences it only if it is very good after the MP. The alignment of the HCF does also seem to influence the CEP stability and the best stability appears to coincide with maximum output energy. An acousto-optic modulator (Dazzler) has been used to manipulate the CEP change at the end of the system and can thereby compensate for long-term drifts, but the source of the CEP stability degradation at the end of the system should be further investigated.

42

Bejeryd, Johan. "GPS-based attitude determination". Thesis, Linköping University, Department of Electrical Engineering, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-11029.

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Inertial sensors and magnetometers are often used for attitude determination of moving platforms. This thesis treats an alternative method; GPS-based attitude determination. By using several GPS-antennas, and with carrier phase measurements determining the relative distance between them, the attitude can be calculated.

Algorithms have been implemented in Matlab and tested on real data. Two commercial GPS-based attitude determination systems have also been tested on a mobile platform and compared to a navigation grade Inertial Navigation System (INS). The results from the tests show that GPS-based attitude determination works well in open areas, but would require support from additional sensors in urban and forest environments.

43

Anderson, Alexandria [Verfasser]. "Methods of generating carrier-envelope-phase stabilized, intense, few-cycle laser pulses / Alexandria Anderson". Kassel : Universitätsbibliothek Kassel, 2015. http://d-nb.info/1067138145/34.

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44

Ray, Jayanta Kumar. "Mitigation of GPS code and carrier phase multipath effects using a multi-antenna system". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape3/PQDD_0022/NQ49532.pdf.

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45

Dongol, Amit. "Carrier Dynamics and Application of the Phase Coherent Photorefractive Effect in ZnSe Quantum Wells". University of Cincinnati / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1396453493.

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46

Raabe, Johannes Nils [Verfasser]. "Fundamental Carrier-Envelope Phase Noise Limitations during Pulse Formation and Detection / Johannes Nils Raabe". Berlin : Freie Universität Berlin, 2020. http://d-nb.info/1204926697/34.

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47

Rapp, Philipp [Verfasser]. "Model-based optoacoustic indoor localization using code modulation and carrier phase estimation / Philipp Rapp". Düren : Shaker, 2020. http://d-nb.info/121193098X/34.

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48

Pitarokoilis, Antonios. "On the performance of Massive MIMO systems with single carrier transmission and phase noise". Licentiate thesis, Linköpings universitet, Kommunikationssystem, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-97489.

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In the last decade we have experienced a rapid increase in the demand for high data rates over cellular networks. This increase has been partly satisfied by the introduction of multi-user multiple-input multiple-output (MU-MIMO). In such systems, the base station (BS) is equipped with multiple antennas and the users share the time-frequency resources. However, modern communication systems are highly power inefficient. Further, the increase in demand for higher data rates is expected to accelerate in the years to come due to the popularity of mobile devices like smartphones and tablets. Hence, next generation cellular systems arerequired to exhibit high energy efficiency as well as low power consumption. Recently, it has been shown that the deployment of a large excess of base station (BS) antennas in comparison to the served users can be a promising candidate to meet these contradictory requirements. These systems are termed as Massive MIMO. When the number of BS antennas grows large, the channels between different users become orthogonal and low complexity transceiver processing exhibits sum-rate performance that is close to optimal. In order to realize the promised gains of Massive MIMO systems, it is required that power efficient and inexpensive components are used. In contemporary cellular systems, multi-carrier transmission is used since it facilitates simple equalization at the receiver side. However, multi-carrier signals exhibit high peak-to-average-power-ratio (PAPR) and require expensive highly linear power amplifiers. Power amplifiers in this regime are also very power inefficient. On the other hand single carrier signals exhibit lower PAPR and are suitable for signal design that is more robust to non-linear power amplifiers. Further, single-carrier signals are less vulnerable to hardware impairments, such as phase noise. In this thesis we study the fundamental limits of Massive MIMO systems in terms of sum-rate performance with single-carrier transmission and phase noise and provide important insight on the design of Massive MIMO under these scenarios.

49

Kalyanaraman, Sai K. "High Accuracy GPS Phase Tracking Under Signal Distortion". Ohio University / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1251221460.

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50

Oguz, Pinar. "Implementation Of Northfinding Techniques". Master's thesis, METU, 2006. http://etd.lib.metu.edu.tr/upload/12607271/index.pdf.

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ABSTRACT IMPLEMENTATION OF NORTHFINDING TECHNIQUES Oguz, Pinar MS, Department of Electrical and Electronics Engineering Supervisor: Assoc. Prof. Dr. T.Engin Tuncer June 2006, 131 pages The fundamental problem of navigation is to find the initial north angle of the body with respect to the reference frame. Determination of the north angle of the body frame is required in spacecraft, aircraft, sea-craft, land-craft and missile control and guidance. This thesis discusses implementation and comparison of four northfinding techniques. These are GPS (Global Positioning System) based with integer search, GPS based with Kalman filter, accelerometer based and IMU (Inertial Measurement Unit) based techniques. The north angle is determined by the processing of difference measurements of the GPS carrier phase between two antennas at GPS based northfinding techniques. Carrier phase ambiguity resolution is the main problem in GPS based techniques. Since, GPS receiver measures only the fractional part of the carrier phase. Therefore, integer part remains unknown. Two distinct ideas are applied to solve carrier phase ambiguities in two techniques. One of them is integer search on single phase difference. Suitable integer sets are checked on the cost function which is constructed from the single phase difference between two antennas. The other technique uses integer estimator and attitude estimator with Kalman filter rely on double difference phase measurements which are obtained from carrier phase differences of two antennas and two satellites at one instant. To test the GPS based techniques, a realistic GPS emulator is implemented. GPS emulator provides typical GPS raw navigation data including satellite positions, pseudoranges and carrier phases. Accelerometer based northfinding technique is composed of a vertically placed linear accelerometer on a rotating platform. The north angle is found by Coriolis acceleration due to Earth and platform rotation. Implementation problems of this technique in practice are discussed. IMU based northfinding technique has inertial sensor components such as gyroscopes and accelerometers to sense the Earth rotation rate and gravitational force respectively. The north angle is found by the processing of these inertial sensors output. Real set-up is established to test the IMU based technique.

Tesi sul tema "Carrier phases"

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