Acknowledgements section and vita redacted from this digital version.

The objective of this research is to demonstrate the feasibility of the implementation of wideband RF CMOS PLLs with high spectral purity using deep sub-micron technologies. To achieve wide frequency coverage, this dissertation proposed a 45-nm SOI-CMOS RF PLL with a wide frequency range to support multiple standards. The PLL has small parasitic capacitance with the help of a SOI technology, increasing the frequency tuning range of a capacitor bank. A designed and fabricated chip demonstrates the PLL supporting almost all cellular standards with a single PLL. This dissertation also proposed a third order sample-hold loop filter with two MOS switches for high spectral purity. Sample-hold operation improves in-band and out-of-band phase noise performance simultaneously in RF PLLs. By controlling the size of the MOS switches and control time, the nonideal effects of the MOS switches are minimized. The sample-hold loop filter is implemented within a 45-nm RF PLL and the performance is evaluated. Thus, this research provides a solution for wideband CMOS frequency synthesizers for multi-band, multi-mode, and multiple-standard applications in deep sub-micron technologies.

No description available.

Hybrid Digital/RF Envelope Predistortion Linearization for High Power Amplifiers in Wireless Communication Systems Wangmyong Woo 151 Pages Directed by Dr. J. Stevenson Kenney The objective of this research is to implement a hybrid digital/RF envelope predistortion linearization system for high-power amplifiers used in wireless communication systems. It is well known that RF PAs have AM/AM (amplitude modulation) and AM/PM (phase modulation) nonlinear characteristics. Moreover, the distortion components generated by a PA are not constant, but vary as a function of many input conditions such as amplitude, signal bandwidth, self-heating, aging, etc. Memory effects in response to past inputs cause a hysteresis in the nonlinear transfer characteristics of a PA. This hysteresis, in turn, creates uncertainty in predictive linearization techniques. To cope with these nonlinear characteristics, distortion variability, and uncertainty in linearization, an adaptive digital predistortion technique, a hybrid digital/RF envelope predistortion technique, an analog-based RF envelope predistortion technique, and a combinational digital/analog predistortion technique have been developed. A digital adaptation technique based on the error vector minimization of received PA output waveforms was developed. Also, an adaptive baseband-to-baseband test system for the characterization of RF PAs and for the validation of linearization algorithms was implemented in conjunction with the adaptation technique. To overcome disadvantages such as limited correction bandwidth and the need for a baseband input signal in digital predistortion, an adaptive, wideband RF envelope predistortion system was developed that incorporates a memoryless predistortion algorithm. This system is digitally controlled by a look-up table (LUT). Compared with conventional baseband digital approaches, this predistortion architecture has a correction bandwidth that is from 20 percent to 33 percent wider at the same clock speeds for third to fifth order IMDs and does not need a digital baseband input signal. For more accurate predistortion linearization for PAs with memory effects, an RF envelope predistortion system has been developed that uses a combination of analog-based envelope predistortion (APD) working in conjunction with digital LUT-based adaptive envelope predistortion (DPD). The resulting combination considerably decreases the computational complexity of the digital system and significantly improves linearity and efficiency at high power levels.

Satellite-based communications networks can provide personal communications services to markets that are unable to be serviced by terrestrial wireless networks, such as maritime, aviation, military, developing countries and remote industry. Traditional Geostationary Earth Orbit (GEO) satellite communications suffer from high transmit power requirements and long delays. In comparison, Low Earth Orbit (LEO) satellite communications do not suffer these problems, and therefore promise to provide high-quality communications services to small handheld terminals. The convergence of traditional voice, data, fixed, and mobile communications networks, has prompted the extension of common terrestrial networking protocols into terrestrial wireless and satellite networks. The research presented in this thesis focuses on the Asynchronous Transfer Mode (ATM) extensions required to support the frequent satellite handovers that occur in LEO satellite networks. / During the late 1990s, the standards organisation known as the ATM Forum drafted a Wireless ATM (WATM) specification, which included the handover procedures for use in terrestrial WATM networks. It is advantageous to broaden the use of the terrestrial handover procedures to handover scenarios in a LEO satellite network, based on the Iridium constellation, and specifically focuses on the Quality of Service (QoS) provided during handover. / The first contribution of this thesis (Chapter 4) is the identification of a number of performance deficiencies within the ATM forum handover procedures when used in a typical LEO satellite network. The performance deficiencies were identified through analysis of the handover signalling and functionality used in the handover procedure, and were quantified through simulation of the handover procedure (Chapter 7) using the OPNET Modeler discrete event simulation tool. The performance deficiencies result in significant and unacceptable ATM cell loss and increases in ATM cell delays, which have the potential to cause a significant user perceived interruption in communications during handover. / The primary cause of poor performance in the ATM Forum handover procedure is the lack of ATM functionality to specifically control the handover of ATM cells from the existing ATM connection to the new ATM connection. The second contribution (Chapter 5) is the specification of novel ATM-attuned signalling and functionality to improve this aspect of the handover. The new functionality allows an incremental handover of ATM cells to be performed which, in combination with the new signalling messages to support this process, eliminates the potential for ATM cell loss and minimises the increases in ATM cell delay. / The third contribution of this thesis (Chapter 6) is the specification of two new handover procedures, which exploit the novel ATM signalling and functionality described above, to provide a lossless low-delay handover in a LEO satellite network. / The fourth and final contribution (Chapter 7) is the simulation and performance analysis of the ATM Forum handover procedure in a LEO satellite network based on the Iridium constellation. As far as I am aware, there are no other published attempts of its kind, thus making it a unique contribution amongst the literature. Iridium is currently the most sophisticated LEO satellite network in use today, and although it is a narrowband system, the constellation characteristics are suitable for use in a future broadband system. The OPNET Modeler discrete event simulation tool was used to create a satellite ATM simulation model, implementing the ATM Forum handover procedure, and the two new handover procedures specified in Chapter 6. Handover performance was methodically simulated using a comprehensive set of handover scenarios (i.e. handover geometries), ranging from single-user single-connection scenarios to scenarios involving hundreds of users and connections. The handover performance was analysed with respect to the ATM Cell Loss Ratio (CLR) and Cell Delay Variation (CDV) parameters, which are the primary indicators of handover performance, and with respect to the handover latency, which is a secondary indicator of performance. The performance of the ATM Forum handover procedure was shown to severely fail both the recommended ATM and WATM performance objectives in the majority of handover scenarios, rendering it unsuitable for use in a LEO satellite ATM network. Conversely, the new handover procedures suffer no ATM cell loss, and in the vast majority of handover scenarios minimise the increases in ATM cell delay. Hence, the new handover procedures are ideally suited for use in a future broadband LEO satellite ATM network. / Thesis (PhDTelecommunications)--University of South Australia, 2004.

Thesis (Ph.D.)--University of Waikato, 2007. / Title from PDF cover (viewed February 29, 2008) Includes bibliographical references (p. 149-160)

Thesis (M.App.Sc.) - Carleton University, 2005. / Includes bibliographical references (p. 104-106). Also available in electronic format on the Internet.

Thesis (Ph.D.)--Hong Kong University of Science and Technology, 2006. / Adviser: Yan Xu. Includes bibliographical references.

Thesis (Ph. D.)--Auburn University. / Abstract. Includes bibliographical references (p. 151-160).

Thesis (M.B.A.)--University of Hong Kong, 1999. / Includes bibliographical references (leaf viii).