On-line identification investigation

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Implementation of Digital Filters Using Fermat Number Transform On TMS320C30 Digital Signal Processor

Precise systems design, equipment standardization, and stability of performance characteristics are among the many advantages digital techniques can offer in signal processing. Earlier research in this field of study has contributed much to many of the modern day conveniences. Many of these contributions focus on improving computational efficiency of discrete Fourier transform (DFT) calculation. However, there are many shortcomings; therefore number theoretic transform (NTT) is proposed. This study implements three digital filters using one of the NTT, namely the Fermat number transform (FNT), and DFT. It compares the execution time, number of operation, and memory requirement for both implementations. Implementation of both types of filters employs the radix-2 fast Fourier transform (FFT) . This study proposes a modified diminished-one number system in implementing FNT. The number system was originally proposed by Leibowitz. I would like to take this opportunity to thank my major advisor, Dr. Lu, for the encouragement she has offered over the years. Her patience and constructive guidance has been very helpful. Also, I would like to thank Dr. Teague for his kindness in giving me access to his digital signal processing laboratory, where most of the work in this study was done. My appreciation also goes to my parents for their continuous supportComputer Scienc

In -cylinder combustion -based virtual emissions sensing

The development of a real-time, on-board measurement of exhaust emissions from heavy-duty engines would offer tremendous advantages in on-board diagnostics and engine control. In the absence of suitable measurement hardware, an alternative approach is the development of software-based predictive approaches. This study demonstrates the feasibility of using in-cylinder pressure-based variables as the inputs to predictive neural networks that are then used to predict engine-out exhaust gas emissions. Specifically, a large steady-state engine operation data matrix provides the necessary information for training a successful predictive network while at the same time eliminating errors produced by the dispersive and time-delay effects of the emissions measurement system which includes the exhaust system, the dilution tunnel, and the emissions analyzers. The steady-state training conditions allow for the correlation of time-averaged in-cylinder combustion variables to the engine-out gaseous emissions. A back-propagation neural network is then capable of learning the relationships between these variables and the measured gaseous emissions with the ability to interpolate between steady-state points in the matrix. The networks were then validated using the transient Federal Test Procedure cycle and in-cylinder combustion parameters gathered in real time through the use of an acquisition system based on a digital signal processor. The predictive networks for NOx and CO 2 proved highly successful while those for HC and CO were not as effective. Problems with the HC and CO networks included very low measured levels and validation data that fell beyond the training matrix boundary during transient engine operation

Switched-current filtering systems: design, synthesis and software development

Allpass filters are commonly employed in many applications to perform group delay equalisation in the passband. They are non-minimum phase by definition and are characterised by poles and zeros in mirror-image symmetry. SI allpass filters of both cascade biquad and bilinear-LDI ladder types have been in existence. These were implemented using Euler based integrators. Cascade biquads are known to have highly sensitive amplitude responses and Euler integrators suffer from excess phase. The equalisers that are proposed here are based on bilinear integrators instead of Euler ones. Derivation of these equalisers can proceed from either the s-domain, or directly from the z-domain, where a prototype is synthesised using the respective continued-fractions expansions, and simulated using standard matrix methods. The amplitude response of the bilinear allpass filter is shown to be completely insensitive to deviations in the reactive ladder section. Simulations of sensitivities and non-ideal responses reveal the advantages and disadvantages of the various structures. Existing DI multirate filters have to date been implemented as direct-form FIR and IIR polyphase structures, or as simple cascade biquad or ladder structures with non-optimum settling times. FIR structures require a large number of impulse coefficients to realise highly selective responses. Even in the case of linear phase response with symmetric impulse coefficients, when the number of coefficients can be halved, significant overheads can be incurred by additional multiplexing circuitry. Direct-form IIR structures are simple but are known to be sensitive to coefficient deviations and structures with non-optimum settling times operate entirely at the higher clock frequency. The novel SI decimators and interpolators proposed are based on low sensitivity ladder structures coupled with FIR polyphase networks. They operate entirely at the lower clock frequency which maximises the time available for the memory cells to settle. Two different coupling architectures with different advantages and disadvantages are studied

Digital Filters and Signal Processing

Digital filters, together with signal processing, are being employed in the new technologies and information systems, and are implemented in different areas and applications. Digital filters and signal processing are used with no costs and they can be adapted to different cases with great flexibility and reliability. This book presents advanced developments in digital filters and signal process methods covering different cases studies. They present the main essence of the subject, with the principal approaches to the most recent mathematical models that are being employed worldwide

VLSI Design

This book provides some recent advances in design nanometer VLSI chips. The selected topics try to present some open problems and challenges with important topics ranging from design tools, new post-silicon devices, GPU-based parallel computing, emerging 3D integration, and antenna design. The book consists of two parts, with chapters such as: VLSI design for multi-sensor smart systems on a chip, Three-dimensional integrated circuits design for thousand-core processors, Parallel symbolic analysis of large analog circuits on GPU platforms, Algorithms for CAD tools VLSI design, A multilevel memetic algorithm for large SAT-encoded problems, etc

Multimodal Noncontact Tracking of Surgical Instruments

For many procedures, open surgery is being replaced with minimally invasive surgical (MIS) techniques. The advantages of MIS include reduced operative trauma and fewer complications leading to faster patient recovery, better cosmetic results and shorter hospital stays. As the demand for MIS procedures increases, effective surgical training tools must be developed to improve procedure efficiency and patient safety. Motion tracking of laparoscopic instruments can provide objective skills assessment for novices and experienced users. The most common approaches to noncontact motion capture are optical and electromagnetic (EM) tracking systems, though each approach has operational limitations. Optical trackers are prone to occlusion and the performance of EM trackers degrades in the presence of magnetic and ferromagnetic material. The cost of these systems also limits their availability for surgical training and clinical environments. This thesis describes the development and validation of a novel, noncontact laparoscopic tracking system as an inexpensive alternative to current technology. This system is based on the fusion of inertial, magnetic and distance sensing to generate real-time, 6-DOF pose data. Orientation is estimated using a Kalman-filtered attitude-heading reference system (AHRS) and restricted motion at the trocar provides a datum from which position information can be recovered. The Inertial and Range-Enhanced Surgical (IRES) Tracker was prototyped, then validated using a MIS training box and by comparison to an EM tracking system. Results of IRES tracker testing showed similar performance to an EM tracker with position error as low as 1.25 mm RMS and orientation error \u3c0.58 degrees RMS along each axis. The IRES tracker also displayed greater precision and superior magnetic interference rejection capabilities. At a fraction of the cost of current laparoscopic tracking methods, the IRES tracking system would provide an excellent alternative for use in surgical training and skills assessment