Today's wireless transceivers require reference signals to translate received and transmitted signals to their desired frequencies. Therefore, they need frequency synthesizers which are typically based on phase-locked-loops (PLLs). Communication standards like GSM or Bluetooth necessiate that the PLLs put out oscillations with high spectral purity and accuracy. Additionally, the oscillation frequency must be adjustable very accurately at low transient time to account for occasional carrier frequency changes. So called Sigma-Delta-fractional-N frequency synthesizers are often employed to fulfil these requirements. However, the number and the locations of the poles of the control loop and hence the loop filter must be chosen properly. Unity gain frequency and phase margin have to be considered as well as the stringent frequency accuracy and the detailed origin of the spurious emissions. The design methodology proposed in this work is based on numerical optimization techniques, a high number of control loop poles and the use of Gm-C-biquads as loop filter building blocks.
| Identifer | oai:union.ndltd.org:DUETT/oai:DUETT:duett-12162004-201909 |
| Date | 17 December 2004 |
| Creators | Christoffers, Niels |
| Contributors | Prof. Dr.-Ing. Stefan Heinen, Prof. Bedrich J. Hosticka, Ph. D. |
| Publisher | Gerhard-Mercator-Universitaet Duisburg |
| Source Sets | Dissertations and other Documents of the Gerhard-Mercator-University Duisburg |
| Language | German |
| Detected Language | English |
| Type | text |
| Format | application/octet-stream, application/pdf, text/html |
| Source | http://www.ub.uni-duisburg.de/ETD-db/theses/available/duett-12162004-201909/ |
| Rights | unrestricted, I hereby certify that, if appropriate, I have obtained and attached hereto a written permission statement from the owner(s) of each third party copyrighted matter to be included in my thesis, dissertation, or project report, allowing distribution as specified below. I certify that the version I submitted is the same as that approved by my advisory committee. Hiermit erteile ich der Universitaet Duisburg das nicht-ausschliessliche Recht unter den unten angegebenen Bedingungen, meine Dissertation, Staatsexamens- oder Diplomarbeit, meinen Forschungs- oder Projektbericht zu veroeffentlichen und zu archivieren. Ich behalte das Urheberrecht und das Recht das Dokument zu veroeffentlichen und in anderen Arbeiten weiterzuverwenden. |
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