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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

New techniques for measurement and tracking of phase and frequency.

Hill, Martin T. January 1997 (has links)
This thesis presents and analyses new techniques to measure and track the phase and frequency of high frequency narrow bandwidth signals. In particular, these techniques are all digital in nature or can be implemented in digital integrated circuit technology.Presented first is a frequency measurement technique which involves sampling at regular intervals a binary quantized narrow band signal. The binary quantized samples are digitally processed to obtain the instantaneous frequency of the signal.It is shown that small phase movements in the signal can be detected even though the sampling occurs at a rate much lower than the signal frequency; that there are no frequency offsets in the frequency measurement technique; that the phase error in the technique is small and bounded provided the signal frequency is maintained within derived limits. Other properties of the technique are also derived.The frequency measurement technique is experimentally demonstrated in a number of typical applications.Secondly, a new phase tracking system is presented, which has similarities to conventional phase locked loops. However, unlike phase locked loops, the new system incorporates a local reference source which effectively stabilizes the phase estimate of the signal input being tracked.It is shown that the new system has the following advantages: Precise centre frequency, controllable lock range, and elimination or reduction of the effects of imperfections like voltage controlled oscillator phase noise. General behaviour in noise of the new phase tracking system is derived.An implementation of the new system is presented which employs the frequency measurement technique described above. This implementation is characterized by very precise centre frequency, high phase noise suppression, and can be built almost entirely in digital integrated circuit technology. The new system is ++ / experimentally demonstrated in some typical applications.The techniques presented in this thesis provide improvements of several orders of magnitude in the ability of systems implemented in digital integrated circuit technology to: Measure and control phase and frequency of narrow band signals; Implement high performance phase tracking systems.
2

Simple low cost techniques for frequency synthesis

Shekar, Krishna Chandra January 2010 (has links)
Typescript (photocopy). / Digitized by Kansas Correctional Industries
3

Design of compact frequency synthesizer for self-calibration in RF circuits

Park, Sanghoon 01 November 2005 (has links)
A compact frequency synthesizer based on a phase locked loop (PLL) is designed for the self-calibration in RF circuits. The main advantage of the presented frequency synthesizer is that it can be built in a small silicon area using MOSFET interface trap charge pump (ITCP) current generators. The ITCP current generator makes it possible to use small currents at nano-ampere levels so that small capacitances can be used in the loop filter. A large resistance, which is required to compensate for the reduced capacitances, is implemented using an operational transconductance amplifier (OTA). An ITCP current generator is used as a tail current source for the OTA in order to realize a small transconductance. The presented frequency synthesizer has the output frequency range from 570 MHz to 600 MHz with a 100 KHz frequency step. Total silicon area is about 0.3 mm2 using AMIS 0.5 ??m CMOS technology, and the power consumption is 26.7 mW with 3 V single power supply.
4

Regenerative frequency divider

Matthews, Robert Clarence, 1938- January 1962 (has links)
No description available.
5

Some examples of Gram-Charlier frequency curves

Riley, Fred Earl, 1918- January 1941 (has links)
No description available.
6

Frequency domain system identification of fixed-wing unmanned aerial vehicles

Xu, Kaiwen Jr 02 September 2014 (has links)
The goal of this thesis is to identify airplanes’ reduced order transfer functions, and aerodynamic derivatives in the longitudinal channel. The outcome of the research will benefit aircraft systems’ controller design, modeling and simulation. To identify the system transfer functions and aerodynamic derivatives, direct and indirect frequency domain identification methods are applied. For the direct method, the Equation Error (EE) method is adopted to process the Cropcam’s input-output data pairs and identify the aerodynamic derivatives from the flight data directly. The indirect approach is called the Transfer Function (TF) method. The derivatives identified by the EE method and transfer function method are compared with the ones computed from a Vortex Lattice based program called AVL. The identification results are further verified by comparing computer simulation outputs with flight test responses.
7

Estimation of frequency control performance index

Zahid, Zubaer 13 January 2015 (has links)
This thesis proposes two methods to estimate transfer function models using System Identification technique that can be used to estimate Control Performance Standard 1 (CPS1) index. The first method is applicable when a load-frequency time domain simulation system of an interconnected power system for estimation of CPS1 is available. This method models an accurate approximate equivalent power system external to a system under consideration. The second method is applicable when a time domain simulation model for estimation of CPS1 is not available. This method uses System Identification technique to model two transfer functions to produce necessary data for the estimation of CPS1. The necessary up-to-date data for System Identification can be obtained from a practical power system dynamic simulation model. The developed models are used to estimate CPS1. The research described in this thesis also shows the applicability of a previously developed method of estimating CPS1 in a practical power system. The techniques, methodology and results presented in this research should provide useful information for operating and planning of power systems.
8

Integrated RF CMOS frequency synthesizers and oscillators for wireless applications /

Aktas, Adem January 2004 (has links)
Thesis (Ph. D.)--Ohio State University, 2004. / Title from first page of PDF file. Document formatted into pages; contains xix, 217 p.; also includes graphics (some col.). Includes bibliographical references (p. 211-217). Available online via OhioLINK's ETD Center
9

Analysis of monolithic, fractional-n frequency synthesizers.

Madsen, John (John David), Carleton University. Dissertation. Engineering, Electrical. January 1992 (has links)
Thesis (M. Eng.)--Carleton University, 1992. / Also available in electronic format on the Internet.
10

Frequentiecurven

Holwerda, Allard Othmar. January 1913 (has links)
Thesis--Utrecht.

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