This dissertation is concerned with the development and performance analysis of non-linear receivers for detection of weak narrow-band signals in multivariate non-Gaussian clutter. The novelty of the detection scheme lies in the utilization of both the complex measurement and the multivariate non-Gaussian character of the clutter. Two clutter models are developed based on the available partial information. Model (I) is based on the a priori knowledge of the first-order density, correlation structure of the amplitude, and the circular symmetric assumption of the in-phase and quadrature phase components. Model (II) is based on the first-order in-phase and quadrature phase densities and the complex correlation structure. These models completely specify a multivariate complex nonGaussian density and can be used for clutter generation. A class of optimum non-linear receiver structures based on weak signal level, canonically known as Locally Optimum Detectors (LOD) are derived under clutter Model (I). This can be considered to be a generalization of the LOD for the independent and identically distributed (i.i.d) clutter. The detectors utilize complex measurements and their structures depend on whether the underlying hypothesis testing model is real or complex. The performance of each of the proposed detector structures, based on the concept of Efficacy, is formulated. Then, the performance of the detectors are evaluated with respect to a reference detector using Asymptotic Relative Efficiency (ARE) criterion. Numerical evaluation of the performance expression is carried out for constant signal in Weibull distribution for various density parameters. Simulation results indicate that the performance of the developed detectors, based on ARE, is superior to (i.i.d) LOD detector and matched filter. Finally, the sensitivity of the detector performance to parameter variation of the structural non-linearities is investigated. / Ph. D.

D. Tech. (Engineering, Department Electronic Engineering, Faculty of Engineering and Technology), Vaal University of Technolog / Ore, from a mining operation, goes through a process that separates the valuable minerals from the gangue (waste material). This process usually involves crushing, milling, separation and extraction where the gangue is usually discarded in tailings piles. Current physical methods used for crushing of rocks in the mineral processing industry result in erratic breakages that do not efficiently liberate the economically valuable minerals. Research studies have found that the rock comminution and mineral liberation can be enhanced through various electrical treatment techniques, including pulsed power, ultrasound and microwave. These electrical treatment techniques each have their own advantages and disadvantages which are discussed in this dissertation. However, this research proposes a new technique in an attempt to improve the rock comminution process. The main purpose of this research is to evaluate the effect that RF power exerts on rock samples, with particular focus on textural changes. Four valuable scientific contributions to the fields of metallurgical and electrical engineering were made in this regard. Firstly, a new technique for the treatment of rock samples using RF heating is substantiated. The effect of RF power on textural changes of the rocks is evident in their surface temperature rise, where the RF heating of dole-rite (JSA) and marble (JSB, JS 1 and JS2) resulted in surface temperatures of approximately 100 °C within two minutes of treatment. A particle screening analysis of particles obtained form a swing-pot mill of both the untreated (not exposed to RF power) and treated (exposed to RF power) rock samples were performed to ascertain if the treated samples' size had changed. Two samples (JSA and JSD) revealed a notable change in their particle size distribution. The fact that the percentage of larger sized particles increased (from 38 J..Lm to 90 J..Lffi as seen in Chapter 6) suggests that the rock was strengthened rather than weakened. Secondly, an innovative coupling technique (using a parallel-plate capacitor with dimensions of 28 x 47 mm) to connect rock samples to high powered RF electronic equipment is described. The feasibility of this technique is confirmed by repeated correlated measurements taken on a vector voltmeter and network analyser. Low SWR readings obtained from an inline RF Wattmeter in a practical setup also proves the viability of the matching network used in the coupling technique. Thirdly, anoriginal coupling coefficient (81.58 x 10-3) for the parallel-plate capacitor is presented. This value may be used in similar sized capacitors to determine the specific heat capacity of dielectric materials. However, the value of the coupling coefficient was only verified for seven (relatively dark in surface colour) out of the ten rock samples. Therefore, this coupling coefficient may hold true for all dark coloured rock samples, as it represents the coupling of energy between the parallel-plate capacitor and the rock sample. Finally,this research defines the mathematical models for 10 rock samples for the VHF range of frequencies (30 - 300 MHz), providing unique phase angle to resonance equations for each sample. These equations can be used with each specific rock to determine the resonating frequency where the maximum current flows and the minimum resistance is present. Evaluating the effects of RF power treatment on rocks has brought to light that mineral grain boundaries within specified rock samples are not significantly weakened by RF treatment. This was firstly confirmed by the similar electrical properties of the untreated and treated samples, where consistent values for the resonating frequency were obtained from the network analyser. Secondly, the SEM analysis of the untreated and treated rock samples revealed no significant changes in the form of fractures or breakages along the mineral grain boundaries. Photomicrographs of the thin sections of all ten rock samples were used in this analysis. The particle size distribution of both samples further revealed no weakening or softening of the rock, as the percentage of smaller sized particles did not increase in the treated samples. It may therefore be stated that treating rock samples with RF power within the VHF range will not significantly improve rock comminution and mineral liberation.

Este trabalho tem como objetivo apresentar uma Metodologia pra implantar um Modelo de Processo Informado de Supply Chain usando tecnologia RFID (Radio Frequency Identification) aplicado ao Agronegócio. Para criação deste Modelo desenvolveu-se uma Metodologia própria utilizando-se de Ferramentas Computacionais Livres que conduziram a criação de um programa especializado para o Supply Chain da Semente de Milho, que foi o caso escolhido para o estudo. Os procedimentos adotados para criação deste Modelo podem facilmente ser remodelados para outras Cadeias do Agronegócio, tais como a Carne, as Frutas, Grãos Comerciais, gerando assim vantagens competitivas aos produtos até então vistos como puras commodities. As aplicações tradicionais do RFID têm sido limitadas ao posicionamento de produtos em armazéns, deixando abertas muitas possibilidades de estudo, como é o caso do Modelo Informado, permitindo ao consumidor final do produto ter todas as informações necessárias para garantia da qualidade junto ao item. A integração de conhecimentos originados no Supply Chain, Processo Informado, RFID e Agronegócio é feita com base em uma estrutura que distribui a informação entre os equipamentos e bancos de dados associados aos leitores de RFID. Neste trabalho a questão da segurança contra leitura não autorizada não foi incluída. / This paper aims to present a methodology to deploy a Process Model Informed \"Supply Chain\" using RFID (Radio Frequency Identification) applied to Agribusiness and Precision Agriculture. The intent of this proposal is to allow tend users of precision agriculture product to handle all the data need to ensure the quality of a target product. Traditional applications of RFID have been limited to product placement in stores, leaving a wide possibility of innovations in Supply Chain management. This case is strongly observed in agribusiness, a very important issue in Brazilian economy, where commodities are susceptible to failure or block orders. The coalescing of knowledge from Supply Chain, Process Informed, RFID and Agribusiness Study is made by a fair distribution of information among tags and databases, generally connected to RFID readers. Finally, a case study was included related to the supply of corn seeds to a culture inserted in the paradigm of precision agriculture.

Compressed sensing (CS) is a new signal processing approach that has disrupted the Shannon-Nyquist limit based design methodology and has opened promising avenues for building energy-efficient radio frequency integrated circuits (RFICs) for detecting and estimating particular classes (i.e. sparse) of signals. Whether in application domains where naturally occurring signals are sparse or where representations of signals subject to the fidelity limits or configuration settings of the radio equipment are often found to be sparse, the emergence of CS has forced us to re-imagine the radio receiver. While realizing some of the potential benefits promised by theory, CS-RFIC architectures proposed in earlier research were not particularly suitable for mass-market applications. This thesis demonstrates how to take a new signal processing technique all the way to the hardware level. So far, the main focus in literature has been how CS offers a significant advantage for signal processing. This work will show how CS techniques drive novel architectures down to the integrated circuit level. This requires close collaboration between communication system developers, integrated circuit designers and signal processing experts. The trans-disciplinary approach presented here has led to the unification of CS-inspired architectures for wideband signal detection with robust, legacy architectures for high-sensitivity signal reception. The result is a functionally flexible and rapidly reconfigurable CMOS RFIC compactly implemented on silicon with the potential to achieve the cost, size and power targets in mass-market applications. While the focus of this thesis is RF signal finding and reception in frequency, the CS-based RFIC design approach presented here is applicable to a wide range of other applications like direction-of-arrival and range finding. We begin by developing a signal-model driven approach for optimizing the performance of CS RF frontends (RFFEs). We consider sparse multiband signals with supports contained within a frequency span extending from fMIN to fMAX. The resulting quadrature analog-to-information converter (QAIC) is a flexible-bandwidth, blind sub-Nyquist sampling architecture optimized for energy consumption and sensitivity performance. The QAIC addresses key drawbacks of earlier CS RFFE architectures like the modulated wideband converter (MWC) that implement frequency spans extending from 0 to fMAX. While these earlier architectures, a direct implementation of CS signal processing theory, have several beneficial properties, the true cost of their proposed analog frontend significantly diminishes the sensitivity performance and energy savings that CS methods have the potential to deliver. They use periodic pseudo-random bit sequence (PRBS) generators where the clock frequency fPRBS scales up with the maximum signal frequency fMAX. In contrast, fPRBS in the QAIC RFFE scales up with the instantaneous bandwidth IBW, where IBW = ( fMAX − fMIN ). This results in significant performance advantages in terms of energy consumption and sensitivity performance. The QAIC uncouples fPRBS from fMAX by performing wideband quadrature downconversion ahead of analog mixing with PRBSs at an intermediate frequency (IF). However, the dual heterodyne architecture of the QAIC suffers from spurious responses at IF caused by gain and phase imbalance in its wideband downconverter. We then show how the direct RF-to-information converter (DRF2IC) compactly adds CS wideband detection to a direct conversion frequency-translational noise-cancelling (FTNC) receiver by introducing pseudo-random modulation of the local oscillator (LO) signals and by consolidating multiple CS measurements into one hardware branch. The DRF2IC inherits benefits of the FTNC receiver in signal reception mode. In CS wideband detection mode, the DRF2IC inherits key advantages from both the earlier lowpass CS architectures and the QAIC while avoiding the drawbacks of both. It uncouples fPRBS from fMAX in contrast with the MWC. In contrast with the QAIC, the DRF2IC employs a direct conversion RF chain with narrow bandwidth analog components at baseband thereby avoiding frequency-dependent gain and phase imbalance. The DRF2IC chip occupies 0.56mm2 area in 65nm CMOS. In reception mode, it consumes 46.5mW from 1.15V and delivers 40MHz RF bandwidth, 41.5dB conversion gain, 3.6dB noise figure (NF) and -2dBm blocker 1dB compression point (B1dB). In CS wideband detection mode, 66dB operational dynamic range, 40dB instantaneous dynamic range and 1.43GHz instantaneous bandwidth are demonstrated and 6 interferers each 10MHz wide scattered over a 1.27GHz span are detected in 1.2us consuming 58.5mW.

No description available.

This thesis proposes a multifaceted production test and post-silicon yield enhancement framework for RF systems. The three main components of the proposed framework are the design, production test, and post-test phase of the overall integrated circuit (IC) development cycle. First, a circuit-sizing method is presented for incorporating test considerations into algorithms for automatic circuit synthesis/device resizing. The sizing problem is solved by using a cost metric that can be incorporated at minimal computational cost into existing optimization tools for manufacturing yield enhancement. Along with the circuit-sizing method introduced in the design phase, a low-cost test and diagnosis method is presented for multi-parametric faults in wireless systems. This test and diagnosis method allows accurate prediction of the end-to-end specifications as well as for the specifications of all the embedded modules. The procedure is based on application of optimized test stimulus and the use of a simple diode-based envelope detector to extract the transient test response envelope at RF signal nodes. This eliminates the need to make RF measurements using expensive standard testers. To further improve the parametric yield of RF circuits, a performance drift-aware adaptation scheme is proposed that automatically compensates for the loss of circuit performance in the presence of process variations. This work includes a diagnosis algorithm to identify faulty circuits within the system and a compensation process that adjusts tunable components to reduce the effects of performance variations. As a result, all the mentioned components contribute to producing a low-cost production test and to enhancing post-silicon parametric yield.

This thesis has sought to provide another look at RF interference at the fundamental level. While previous interference control and regulation methods have existed in the literature, they were more focused on preventing the interference from happening. On the contrary, we have taken a different approach of correcting the interference once it has happened. This allows the transmitters to be more nonlinear, passive filter design to be eased, and receivers to be aware of interference problems. Under this unifying theme of building intelligent radios where receivers are more cognizant of the transmission environment, we have presented a number of architectures.

Thesis (M.App.Sc.) - Carleton University, 2006. / Includes bibliographical references (p. 124-128). Also available in electronic format on the Internet.

Este trabalho tem como objetivo apresentar uma Metodologia pra implantar um Modelo de Processo Informado de Supply Chain usando tecnologia RFID (Radio Frequency Identification) aplicado ao Agronegócio. Para criação deste Modelo desenvolveu-se uma Metodologia própria utilizando-se de Ferramentas Computacionais Livres que conduziram a criação de um programa especializado para o Supply Chain da Semente de Milho, que foi o caso escolhido para o estudo. Os procedimentos adotados para criação deste Modelo podem facilmente ser remodelados para outras Cadeias do Agronegócio, tais como a Carne, as Frutas, Grãos Comerciais, gerando assim vantagens competitivas aos produtos até então vistos como puras commodities. As aplicações tradicionais do RFID têm sido limitadas ao posicionamento de produtos em armazéns, deixando abertas muitas possibilidades de estudo, como é o caso do Modelo Informado, permitindo ao consumidor final do produto ter todas as informações necessárias para garantia da qualidade junto ao item. A integração de conhecimentos originados no Supply Chain, Processo Informado, RFID e Agronegócio é feita com base em uma estrutura que distribui a informação entre os equipamentos e bancos de dados associados aos leitores de RFID. Neste trabalho a questão da segurança contra leitura não autorizada não foi incluída. / This paper aims to present a methodology to deploy a Process Model Informed \"Supply Chain\" using RFID (Radio Frequency Identification) applied to Agribusiness and Precision Agriculture. The intent of this proposal is to allow tend users of precision agriculture product to handle all the data need to ensure the quality of a target product. Traditional applications of RFID have been limited to product placement in stores, leaving a wide possibility of innovations in Supply Chain management. This case is strongly observed in agribusiness, a very important issue in Brazilian economy, where commodities are susceptible to failure or block orders. The coalescing of knowledge from Supply Chain, Process Informed, RFID and Agribusiness Study is made by a fair distribution of information among tags and databases, generally connected to RFID readers. Finally, a case study was included related to the supply of corn seeds to a culture inserted in the paradigm of precision agriculture.

No description available.