No description available.

Pulse responses are not suitable for evaluating H(z) frequency responses that include digital errors. Digital error effects, however, are conveniently included in H(z) frequency response calculations based on the step response. A non-real time algorithm for computing the frequency response of a real time digital filters based on the filter step response is developed and verified through an example.

The hardware available for digital signal processing is evaluated. The elements required for implementation of digital signal processing applications are identified. These elements--memories, ALUs and multipliers -- are analyzed. Then the operation of parts which make up a range of possible solutions are evaluated. Thus, the graduating engineer is aided in making a transition from the theoretical to the practical world.

The TMS320 single-chip digital signal processor, produced by Texas Instruments, shows promise for a long life-cycle not only because it fills a technical need in the digital signal processing field; but because it also represents an excellent early design. Furthermore, Texas Instruments has provided thorough software and development support. However, this chip was not designed to support digital signal processing applications which require multiple-precision operations. In this paper, algorithms were developed and expressed in macros that provide the capability of modeling systems requiring multiple-precision operations. Finally, a performance envelope showing the system complexity versus sampling bandwidth limitations is provided to show the capability of the TMS320 in digital signal processing applications requiring multiple-precision.

published_or_final_version / Electrical and Electronic Engineering / Doctoral / Doctor of Philosophy

This study proposes employing new filters in various configurations for use in digital communication systems. We believe that significant improvements in such performance areas as transmission rate and synchronization may be achieved by incorporating these filters into digital communications receivers. Recently reported in the literature, these filters may offer advantages over the matched filter which allow enhancements in data rates, ISI tolerance, and synchronization. To make full use of the benefits of these filters, we introduce the concept of parallel signal transmission over a single channel. We also examine the effects of signal set selection and noise on performance.

No description available.

An instrument with the ability to image neutral atomic hydrogen (HI) to cosmic redshift will allow the fundamental properties of the Universe to be more precisely determined; in particular the distribution, composition, and evolutionary history of its matter and energy. The Square Kilometre Array (SKA) is a radio survey telescope conceived with this aim. It will have the observational potential for much further fundamental science, including strong field tests of gravity and general relativity, revealing the origin and history of cosmological re-ionisation and magnetism, direct measures of gravitational radiation, and surveys of the unmapped Universe. And it is the advance of instrumentation that will enable it. This thesis makes three central contributions to radio instrumentation. Digital aperture arrays are a collector technology proposed for the key low- and mid- frequency ranges targeted by the SKA that have the potential to provide both the collecting area and field of view required for deep, efficient all-sky surveys of HI. The 2-Polarisations, All Digital (2-PAD) aperture array is an instrumental pathfinder for the SKA, novel in being a densely-spaced, wide-band aperture array that performs discrete signal filtering entirely digitally. The digital design of the 2-PAD radio receiver and the deployment of the aperture array and signal processing system at Jodrell Bank Radio Observatory is detailed in this thesis. The problem of element anisotropy in small arrays, the atomic unit of the SKA station array, ultimately affects beam quality. Addressing this issue, a metaheuristic digital beam-shape optimisation technique is applied to a small beamformed array, and is shown to outperform traditional analytic solutions. Digital processing for aperture arrays is challenging. A qualitative framework shows that energy, computational and communication requirements demand optimised processing architectures. A quantitative model reveals the physical limitations on architecture choice. An energy-optimised architecture, the IBM BIT integer array processor, is investigated in detail; a cycle-accurate architectural simulator and programming language are developed and used to build signal processing algorithms on the array architecture.

University of Macau / Faculty of Science and Technology. / Department of Electromechanical Engineering

To Kin Fai. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2000. / Includes bibliographical references (leaves 99-104). / Abstracts in English and Chinese. / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Multi-carrier Communication Systems --- p.1 / Chapter 1.2 --- Objective of the Thesis --- p.4 / Chapter 1.3 --- Thesis Outline --- p.5 / Chapter 2 --- Wavelet Packet Division Multiplexing (WPDM) --- p.7 / Chapter 2.1 --- "Wavelets, Wavelet Packets and Multiresolution Analysis (MRA)" --- p.8 / Chapter 2.2 --- Application of Wavelet Packets in Multiple Signal Transmission --- p.14 / Chapter 2.3 --- Summary --- p.20 / Chapter 3 --- Nonlinear System Theories --- p.22 / Chapter 3.1 --- Characteristics of Memoryless Nonlinearities --- p.23 / Chapter 3.1.1 --- Memoryless Baseband Nonlinearities --- p.23 / Chapter 3.1.2 --- Memoryless Bandpass Nonlinearities --- p.24 / Chapter 3.2 --- Volt err a Series for Nonlinearities with Memory --- p.26 / Chapter 3.2.1 --- Baseband Nonlinearities with Memory --- p.26 / Chapter 3.2.2 --- Bandpass Nonlinearities with Memory --- p.27 / Chapter 3.3 --- High Power Amplifier (HPA) Models --- p.28 / Chapter 3.3.1 --- Traveling Wave Tube Amplifier (TWTA) --- p.28 / Chapter 3.3.2 --- Solid State Power Amplifier (SSPA) --- p.28 / Chapter 3.3.3 --- Input and Output Backoff Ratios --- p.29 / Chapter 3.4 --- Summary --- p.29 / Chapter 4 --- WPDM in the Presence of Amplifier Nonlinearities --- p.30 / Chapter 4.1 --- System Model --- p.31 / Chapter 4.2 --- Derivation of Channel Models --- p.32 / Chapter 4.2.1 --- Single-carrier WPDM --- p.32 / Chapter 4.2.2 --- Multi-carrier WPDM --- p.34 / Chapter 4.3 --- Performance Analysis --- p.35 / Chapter 4.3.1 --- Conditional Mean --- p.36 / Chapter 4.3.2 --- Conditional Variance --- p.41 / Chapter 4.3.3 --- Power Spectral Density (PSD) --- p.44 / Chapter 4.4 --- Probability of Symbol Error --- p.48 / Chapter 4.5 --- Simulation Results --- p.52 / Chapter 4.6 --- Summary --- p.56 / Chapter 5 --- Nonlinear Compensation (The pth-Order Inverse) --- p.57 / Chapter 5.1 --- Data Predistortion --- p.58 / Chapter 5.2 --- Predistorter Structure --- p.62 / Chapter 5.3 --- Complexity --- p.63 / Chapter 5.4 --- Simulation Results --- p.66 / Chapter 5.5 --- Summary --- p.78 / Chapter 6 --- Conclusions and Suggestions for Future Research --- p.79 / Chapter 6.1 --- Conclusions --- p.79 / Chapter 6.2 --- Suggestions for Future Research --- p.82 / Appendices --- p.83 / Chapter A --- Derivation of (4.14) --- p.83 / Chapter B --- Derivation of (4.16) --- p.85 / Chapter C --- Evaluation of higher order expectations --- p.86 / Chapter D --- Derivation of φ ss(T) in (4.32) --- p.90 / Chapter E --- Derivation of φsi(T) in(4.32) --- p.93 / Chapter F --- Derivation of φ is(T) in (4.32) --- p.95 / Chapter G --- Derivation of φii(T) in (4.32) --- p.97 / Bibliography --- p.99