A necessidade da medicina por equipamentos eletrônicos portáteis, menores, confiáveis e baratos favorece o desenvolvimento de técnicas biotelemétricas passivas de monitoração nas aplicações biomédicas invasivas. Nesse trabalho são apresentados o desenvolvimento e o teste de um dispositivo sensor biotelemétrico passivo, que utiliza a tecnologia de identificação por radio freqüência - RFID (Radio Frequency Identification). O dispositivo desenvolvido, comumente chamado como tag, é comporto basicamente por três partes: a arquitetura RFID utilizada para baixa freqüência, a unidade de controle responsável pelo processamento dos dados e a unidade sensora responsável pela monitoração da pressão arterial. Como o tag e passivo, ou seja, não contém baterias, para que seja ativado é necessário um aparelho que faça sua energização e também decodifique os dados por ele transmitidos. Este aparelho que faz a leitura e envia um sinal para ativar o transponder é comumente chamado de leitora. A leitora utilizada neste projeto terá seu firmware adaptado de forma a processar o valor da pressão enviada pelo tag. São abordados neste trabalho tanto a modelagem teórica do sistema quanto a especificação prática dos componentes para os testes de validação. Na modelagem teórica são apresentados os modelos matemáticos comportamentais do sistema. Os resultados obtidos validam a metodologia utilizada para o desenvolvimento de um sensor RFID passivo que tem como finalidade mensurar a pressão arterial. / The need of medicine for portable electronic equipments smallers [sic], reliables [sic] and inexpensive supports the development of biotelemetry techniques passive monitoring in invasive biomedical applications. In this work are presents [sic] the development and testing of a passive biotelemetry sensor device, which uses the technology of Radio Frequency Identification - RFID. The developed device, commonly referred to as the tag, is basically composed of three parts: the RFID architecture used for low frequency, the control unit responsible for data processing and sensor unit responsible for monitoring blood pressure. As the tag is passive i.e. does not contain batteries to activate it, It [sic] is necessary a device that makes its energizing and also decode the data transmitted by it. This device that reads and sends a signal to activate the transponder is commonly called a reader. The reader used in this project will have its firmware adapted to handle the pressure value sent by the tag. This work also presents theoretical modeling of the system and the specification of components for practicing the validation tests. In theoretical modeling are presented mathematical models of system behavior. The results validate the methodology used for the development of passive RFID sensor that aims to measure blood pressure.

Orientador: Carlos Alberto dos Reis Filho / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação / Made available in DSpace on 2018-08-12T22:43:50Z (GMT). No. of bitstreams: 1 Thiebaut_MatthieuJacquesAndre_M.pdf: 11116037 bytes, checksum: 353c725fb0cc60a33445209f0ec29a81 (MD5) Previous issue date: 2006 / Resumo: O objetivo deste trabalho é propor uma topologia de receptor adequada para atender as exigências de uma rede de sensores sem fio, onde baixo consumo e baixo custo de fabricação são fundamentais.A topologia escolhida foi a do receptor super-regenerativo realizado em tecnologia CMOS 0,35Km e operando em 900 MHz. O chip foi montado e testado numa placa de alumina junto com alguns componentes passivos externos (circuito tanque e adaptação de impedância) necessários para seu funcionamento. Uma sensibilidade de -82 dBm para uma taxa de erro binário (BER) inferior a 0,1% foi obtida com um sinal modulado tudo-ou-nada (On-Off keying, OOK) de 64 kbits/s. O consumo deste receptor foi de 2,5 mW para uma tensão de alimentação de 2V. / Abstract: The purpose of this work is to develop a radio receiver, which is suitable for application in wireless sensor networks. Among the essential requirements for one such radio are included low power, low cost and high sensitivity. The topology of a super-regenerative receiver to operate in 900MHz was chosen, since it complies with all these requirements in addition to being appropriate for integration. Samples of the developed radio receiver were fabricated in 0,35Km CMOS technology. Prototypes were assembled on alumina plate using a few additional external components as an alternative to evaluate the performance of the radio without being affected by the low quality of the passives L and C used in the tuning block (tank and matching circuit). Test results have shown that the developed receiver features sensitivity of -82 dBm for a bit error rate (BER) lower than 0,1% with an On-Off Keying modulated signal of 64 kbit/s. Measure power consumption has been 2,5 mW for a supply voltage of 2 V. / Mestrado / Eletrônica, Microeletrônica e Optoeletrônica / Mestre em Engenharia Elétrica

The development of radio frequency integrated circuits (RFICs), especially the dream of integrating analog, digital and radio frequency (RF) components on the same chip that is commonly known as System-on-a-Chip (SoC), is crucial to mobile communications of the future. Such SoC approach offers enhanced performance, greater reliability, and substantially less power consumption of integrated circuits while reducing overall physical size and thus manufacturing cost. However, the progress has been stalled by the lack of miniaturized inductor elements. Rise of unwanted parasitic effects limits down-scaling of the inductor structures and leaves the use of magnetic coating as a viable and attractive option to enhance the inductance and thus inductance density. It is also essential to shift from perm alloy and other amorphous alloys to ferrites and hex ferrites as the core material because of their very high electrical resistivity so as to keep losses in check, a criterion that cannot be compromised on in GHz frequency applications. This is viable, however, only if the integration of the magnetic core (film), particularly a ferrite film, is fully compatible with the CMOS fabrication process. Various approaches have been taken to meet this requirement, including investigations of employing layers of ferrite materials to envelop the inductor loop. However, the deposition of thin films of ferrites, whether by PVD or CVD, usually calls for the deposited ferrite layer to be annealed at an elevated temperature to crystallize the layer so that its magnetic characteristics are appropriate for the optimum performance of the circuit element. Such annealing is incompatible with CMOS process flow required for aggressive device geometries, as the inductor element is added after the active semiconductor circuit is processed, and any exposure of the processed circuit to elevated temperatures risks disturbing precise doping profiles employed and the integrity of the inter-layer dielectrics. What is called for is a low-temperature process for the deposition of a ferrite layer on top of the patterned inductor element – a layer of thickness such that most of the fringe field is encapsulated – while ensuring that the layer comprises crystallites of uniform size that leads to uniform magnetic behaviour. Recognizing the difficulty of meeting the various stringent requirements, it has recently been remarked that such a goal is a formidable challenge. In an attempt to address this challenge, in this work, we have adopted a counter-intuitive approach - the deposition of the desired ferrite composition on a processed die (that contains the inductor structures along with active semiconductor circuits) by immersing it into a chemical (reactant) solution, followed by a brief irradiation of microwave frequency. However, to identify the desired ferrite composition and the appropriate recipe to deposit them, a systematic effort had to be made first, to understand the inter-relationship between synthesis process, structure of resulting material, and its physical and chemical properties. Therefore, at the beginning, a general introduction in which key concepts related to the magnetic-core inductors, the microwave-irradiation-assisted synthesis of nanostructures, the ‗state of the art‘ in the field of integration of appropriate magnetic material to the RFICs, are all outlined. As a proof of concept, microwave-irradiation-assisted solution-based deposition of zinc ferrite thin films on the technologically important Si (100) substrate is demonstrated. The highlight of the process is the use of only non-toxic metal organic precursors and aqua-alcoholic solvents for the synthesis, which is complete in 10 minutes @< 100 °C, without any poisonous by-products. Effects of various process parameters such as solute concentrations, surfactant types, and their concentrations are investigated. A wide range of deposition rates (10 - 2000 nm/min) has been achieved by tweaking the process parameters. The simultaneous formation of zinc ferrite nanocrystallites (ZFNC) along with deposition of thin film is the hallmark of this synthesis technique. Unlike its bulk counterpart, both film and powder are found upon investigation to be rich in magnetic behavior– owing to plausible cationic distribution in the crystal lattice, induced by the inherently quick and far-from-equilibrium nature of the process. The accurate estimation of magnetic characteristics in film is, however, found to be difficult due to the high substrate-to-film mass ratio. The simultaneously prepared ZFNC is examined to arrive at the optimized process recipe that imparts the desired magnetic properties to the zinc ferrite system. The crystallographic cationic distribution in zinc ferrite powder is, however, difficult to study due to the nanoscale dimension of the as prepared material. To enable crystal growth, slow and rapid annealing in air at two different temperatures are employed. The effects of these annealing schemes on various attributes (magnetic properties in particular) are studied. Rapid annealing turns out to be an interesting pathway to promote rapid grain-growth without disturbing the crystallographic site occupancies. The presence of inversion, i.e., the amount of Fe3+ in the ‗A‘-sites in the spinel structure that ideally is zero in normal spinel structure of zinc ferrite, is evident in all annealed ZFNC, as determined by Riveted analysis. Such partially inverted ZFNC exhibits soft magnetic behavior with high saturation magnetization, which can easily be ―tuned‖ by choosing appropriate annealing conditions. However, a few unique strategic modifications to the same microwave-irradiation-assisted solution-based synthesis technique are tried for the formation of nanocrystalline powder with desired sizes and properties without the necessity of anneal. The approach eventually appears to pave a way for the formation of oriented structures of zinc ferrite. The effects of anneal, nevertheless, are studied with the help of neutron powder diffractometry and magnetic measurements. The magnetic ordering at various temperatures is analyzed and connected to the magnetic measurements. The study shows that long-range magnetic ordering, present even at room temperate, originates from the distribution of cations in the partially inverted spinel structures, induced by the rapid and kinetically driven microwave synthesis. Keeping the mild nature (<200 °C) of the processing in mind, a large degree of inversion (~0.5) is a surprise and results in a very high saturation magnetization, as much as 30 emu/g at room temperature (paramagnetic in bulk), in the ZFNC system. Based on the knowledge of process-structure-property interrelationship, a recipe for the deposition of ferrite thin films by the microwave-assisted deposition technique is optimized. Successful deposition of smooth and uniform zinc ferrite thin films on various substrates is, then, demonstrated. The mystery behind the strong adherence of the film to the substrate - an unexpected outcome of a low-temperature process - is probed by XPS and the formation of silicates at the interface is identified as the probable reason. The uniformity and consistency of film composition is also examined in this chapter. Another salient feature of the process is its capability to coat any complex geometry conformally, allowing the possibility of depositing the material in a way to ―wrap around‖ the three-dimensional inductor structures of RF-CMOS. Integration of nanostructure zinc ferrite thin films onto on-chip spiral inductor structures has been demonstrated successfully. The magnetic-core inductors so obtained exhibit the highest inductance density (700 nH/mm2) and the highest Q factor (~20), reported to date, operate at 5 GHz and above, by far the highest reported to date. An increase in inductance density of as much as 20% was achieved with the use of just 1 µm thick film of zinc ferrite covering only the ―top‖ of the spiral structure, i.e., up to 20% of chip real estate can potentially be freed to provide additional functionality. The microwave-assisted solution-based deposition process described in this thesis is meant for ‗post-CMOS‘ processing, wherein the film deposited on some specific electronic components can add desired functionality to or improve the performance of a component (circuit) underneath. However, the effect of such ‗post-CMOS‘ processing on the active MOS devices, interconnects, and even inter-layer-dielectrics fabricated prior to the deposition has to be mild enough to leave the performance of delicate MOS characteristics intact. Such CMOS-compatibility of the present deposition process has been tested with a satisfactorily positive result.

Continuing advances in laser and photonic technology has seen the development of lasers with increasing power and increasingly short pulsewidths, which have become available over an increasing range of wavelengths. As the availability of laser sources grow, so do their applications. To make better use of this improving technology, understanding and controlling laser propagation in free space is critical, as is understanding the interaction between laser light and matter. The need to better control the light obtained from increasingly advanced laser sources leads to the emergence of beam engineering, the systematic understanding and control of light through refractive media and free space. Beam engineering enables control over the beam shape, energy and spectral composition during propagation, which can be achieved through a variety of means. In this dissertation, several methods of beam engineering are investigated. These methods enable improved control over the shape and propagation of laser light. Laser-matter interaction is also investigated, as it provides both a means to control the propagation of pulsed laser light through the atmosphere, and provides a means to generation remote sources of radiation.

M. Tech. (Department of Process Control and Computer Systems, Faculty of Engineering and Technology), Vaal University of Technology. / Radio Frequency Identification Technology (RFID) technology is increasingly being used in multiple applications due to its low cost and ability to provide a high quality of identification. The cost benefit of RFID system is seen in the reduction in labor required to perform routine tasks such as inventory. With RFID, inventory-related tasks can be done in substantially less time compared to other commonly used auto-identification systems. Recent research has illustrated the application of RFID in multiple application scenarios. RFID can be used for real-time patient identification and monitoring in hospitals, but also for product expiration-date management in retail industries. Some enterprises in South Africa uses a combination of RFID technology and Internet of Things (IoT) to detect misplaced products and to detect low stock levels. Furthermore, RFID is also used for inventory management in libraries as discussed in this dissertation. In this dissertation, a combination of RFID and ZigBee technologies was used to reduce the time spent to perform inventory in libraries. An inventory management system was designed, simulated and built in order to count and locate books inside a library hence improving inventory process time in libraries. The overall results were satisfactory which lead to the achieving of the objectives set in this study.

Due to the demand for low-cost, small-form factor and large-scale integration of system-on-chip wireless transceivers, the image-reject, zero-IF and low-IF receiver architectures have become the main topologies used in mainstream wireless communication systems. Consequently, signal sources with quadrature phase outputs [quadrature oscillators (QOs)] are therefore essential, and their phase noise, driving capability, tuning range, oscillation frequency, and power consumption have a major impact on the overall receiver performance. Additionally, it is required that the QO synthesize precise I/Q waveforms across the signal bandwidth over process, voltage, and temperature variations for adequate image-rejection and signal modulation/demodulation. While the use of symmetrical layout and large inter-digitated devices minimize both systematic and random mismatches, this solution alone may not succeed in achieving the stringent performance requirements dictated by modern wireless standards particularly as the technology scales into the sub-100nm regime, necessitating both phase and gain calibration of the mismatched I/Q channels post-fabrication. Given the necessity for precise RF quadrature signal synthesis, the goal of this work is to investigate low-power low-phase-noise quadrature oscillator (QVCO) topologies with an integrated phase calibration feature. The first part of this work focuses on the analysis and modeling of cross-coupled LC QVCOs. The analysis focuses on understanding the oscillator basic performance characteristics, design trade-offs, phase-noise performance, effect of including phase shift in the coupling paths, and on examining the quadrature accuracy in presence of process variations. New design parameters and circuit insight are developed and a generalized first order linear model and a one-port model are proposed. Particularly, we introduce the concept of an effective core and coupling transconductances to explain various oscillator properties. Additionally, a new incremental circuit element — the quadrature resistance — is introduced to evaluate the effect of coupling on the open-loop quality factor and hence on the oscillator phase noise performance. Mechanisms affecting the mode selectivity are identified and modeled. A qualitative and quantitative study of the effect of mismatch on the phase imbalance and amplitude error is presented. Particularly, closed-form intuitive expressions of the phase imbalance and amplitude error are derived and verified via circuit simulation. Based on our understanding of the various mechanisms affecting the quadrature accuracy, the second part of this work introduces a very efficient quadrature phase calibration technique based on the disconnected-source parallel-coupled LC QVCO topology. The phase-tunable LC QVCO (PT-QVCO) achieves an ultra-wide I/Q phase tuning range without affecting the relative amplitude error or consuming additional power or chip area. Additionally, in restoring the phase balance, it is observed that the proposed method restores the phase noise performance to its optimal value which presents a potential advantage over classical calibration techniques. Time domain measurements performed on a 5 GHz prototype show that I/Q signals with phase error up to ~±30°, beyond which the VCO cores are unlocked, can be driven to perfect quadrature phase. The PT-QVCO can be tuned from 3.87-4.45 GHz at the negative mode and 4.4-5.4 GHz at the positive mode, a total of ~1.5 GHz. The fabricated circuit including pad structures occupies an area of 1.1x0.7 mm² and drains 18mW (excluding buffer circuits) from a 1.8 V supply voltage. The third part of this work introduces a new low-power, low-phase-noise super harmonic injection-coupled LC QVCO (IC-QVCO) topology. Analysis of the waveform accuracy reveals an inverse dependence of the quadrature error on the tank quality factor thus allowing circuit optimization for both low phase noise and precise quadrature synthesis. Additionally, a tunable tail filter (TTF) is incorporated to calibrate the residual quadrature imbalance in presence of a 3-σ variation in the device parameters. An X-band IC-QVCO prototype with a TTF implemented in a 0.18μm RF CMOS process, achieves a measured phase noise figure-of-merit ranging from 177.3 to 182.6 dBc/Hz along the 9.0 to 9.6 GHz frequency tuning range while dissipating only 9mW from the 1.8V supply. The TTF reduces both the 1/f² and 1/f³ phase noise and calibrates the residual phase error within ±11° post-fabrication without affecting the relative amplitude error or the phase noise performance. The circuit performance compares favorably with recently published work. In the fourth part of this work, we explore the implementation of LC QVCOs as potential I/Q sources at millimeter-wave (MMW) frequencies. Among the several design challenges that emerge as the oscillator frequency is scaled into the MMW band, precise quadrature synthesis and adequate frequency tuning range are among the hardest to achieve. After describing the limitation of using an MOS varactor and a digitally controlled switch capacitor array for frequency tuning, we propose an alternative frequency tuning technique based on the fundamental operation of LC QVCOs. The off-resonance operation, which is defined by the coupling network, suggests varying the coupling current to achieve frequency tuning. In essence, by modifying the bias current of the coupling transistors (G_Mc-tuning), a wide and linear frequency tuning range can be achieved. Extensive simulation results of a 60 GHz prototype, implemented in a 90 nm commercial RF CMOS process, demonstrates a 5 GHz of frequency tuning range (57.5 GHz → 62.5 GHz), a tuning sensitivity of 1GHz/mA, and a 4dB improvement in the phase noise compared to a varactor solution. Finally, the Appendix includes recent research work on the analysis and design of g<sbu>m</sub>-boosted common-gate low-noise amplifiers (CG-LNAs). While this topic seems to diverge from the main theme of the dissertation, we believe that the comprehensive analysis and the originality of the circuit design introduced in this work are worth acknowledging. / Ph.D. / While resting in bed due to illness, the Dutch scientist Christiaan Huygens keenly observed that the pendulums of two clocks hanging on the wall moved synchronously when the clocks were hung close to each other. He concluded that these two oscillatory systems were forced to move in unison by virtue of mechanical coupling through the wall. In essence, each pendulum injected mechanical vibrations into the wall that was strong enough to lock the adjacent pendulum into synchronous motion. Injection locking of oscillatory systems plays a critical role in communication systems ranging from frequency division, to generating clocks (oscillators) with finer phase separation, to the synthesis of orthogonal (quadrature) clocks. All communication systems have the same basic form. Firstly, there will some type of an information or data source which can be a keyboard or a microphone in a smartphone. The source is connected to a receiver by some sort of a channel. In wireless systems, the channel is the air medium. Moreover, to comply with the FCC and 3GPP requirements, data can only be transmitted wirelessly within a predefined set of frequencies and with stringent emission requirements to avoid interference with other wireless systems. These frequencies are generated by high fidelity clock sources, also known as oscillators. Consider a group of people sharing the same room and hence the same channel want to share information. Without regulating the “loudness” of each communicating ensemble, the quality of communication can be severely impaired. Moreover, it is to be expected that information can be shared more efficiently if each pair is allocated non-overlapping timeslots – speak when others are quiet. Called time orthogonality, all wireless systems require precise orthogonal (quadrature) clock sources to improve the communication efficiency. The precision of quadrature clocks is determined by the amplitude and phase accuracy. This dissertation takes a deep dive into the analysis and implementation of high accuracy quadrature (I/Q) clock sources using the concept of injection locking. These I/Q clocks or oscillators, also known as quadrature voltage controlled oscillators (QVCOs), have gained enormous popularity in the last decade. The first part of this work focuses on the analysis and modeling of QVCOs. The analysis focuses on understanding the oscillator basic performance characteristics, and on examining the quadrature accuracy in presence of process variations. New design parameters and circuit insight are developed and a generalized first order linear model and a one-port model are proposed. A qualitative and quantitative study of the effect of mismatch on the phase imbalance and amplitude error is presented. Particularly, closed-form intuitive expressions of the phase imbalance and amplitude error are derived and verified via circuit simulation. Based on our understanding of the various mechanisms affecting the quadrature accuracy, the second part of this work introduces a very efficient quadrature phase calibration technique based The phase-tunable QVCO (PT-QVCO) achieves an ultra-wide I/Q phase tuning range without affecting the oscillator other performance metrics. The proposed topology was successfully verified in silicon using a 5GHz prototype. The third part of this work introduces a new low-power, low-phase-noise injection coupled QVCO (IC-QVCO) topology. An X-band IC-QVCO prototype was successfully verified in a 0.18m RF CMOS process. In the fourth part of this work, we explore the implementation of QVCOs as potential I/Q sources at millimeter-wave (MMW) frequencies. Among the several design challenges that emerge as the oscillator frequency is scaled into the MMW band, precise quadrature synthesis and adequate frequency tuning range are among the hardest to achieve. After describing the limitation of using an conventional frequency tuning techniques, we propose an alternative approach based on the fundamental operation of QVCOs that outperforms existing solutions.

Thesis (D. Tech. (Electrical Engineering)) - Central University of technology, Free State, 2012 / Radio frequency identification technology (RFID) has emerged as a key technology for automatic identification and promises to revolutionize business processes. While RFID technology adoption is improving rapidly, reliable and widespread deployment of this technology still faces many significant challenges. The key deployment challenges include how to use the simple, unreliable raw data generated by RFID deployments to make business decisions; and how to manage a large number of deployed RFID devices. In this thesis, a multi-agent based RFID middleware which addresses some of the RFID data and device management challenges was developed. The middleware developed abstracts the auto-identification applications from physical RFID device specific details and provides necessary services such as device management, data cleaning, event generation, query capabilities and event persistence. The use of software agent technology offers a more scalable and distributed system architecture for the proposed middleware. As part of a multi-agent system, application-independent domain ontology for RFID devices was developed. This ontology can be used or extended in any application interested with RFID domain ontology. In order to address the event processing tasks within the proposed middleware system, a temporal-based RFID data model which considers both applications’ temporal and spatial granules in the data model itself for efficient event processing was developed. The developed data model extends the conventional Entity-Relationship constructs by adding a time attribute to the model. By maintaining the history of events and state changes, the data model captures the fundamental RFID application logic within the data model. Hence, this new data model supports efficient generation of application level events, updating, querying and analysis of both recent and historical events. As part of the RFID middleware, an adaptive sliding-window based data cleaning scheme for reducing missed readings from RFID data streams (called WSTD) was also developed. The WSTD scheme models the unreliability of the RFID readings by viewing RFID streams as a statistical sample of tags in the physical world, and exploits techniques grounded in sampling theory to drive its cleaning processes. The WSTD scheme is capable of efficiently coping with both environmental variations and tag dynamics by automatically and continuously adapting its cleaning window size, based on observed readings.

In the thesis the design of process tolerant, use-aware radio-frequency front-ends were explored. First, the design of fuzzy logic and equation based controllers, which can adapt to multi-dimensional channel conditions, are proposed. Secondly, the thesis proves that adaptive systems can have multiple modes of operation depending upon the throughput requirements of the system. Two such modes were demonstrated: one optimizing the energy-per-bit (energy priority mode) and another achieving the lowest power consumption at the highest throughput (data priority mode). Finally, to achieve process tolerant channel adaptive operation a self-learning methodology is proposed which learns the optimal re-configuration setting for the system on-the-fly. Implications of the research are discussed and future avenues of further research are proposed.

Thesis (MScEng)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: A methodology is developed to manage the large number of RFI Culprits on a new Radio Telescope location such as the South African site being developed in the Karoo, both during construction and ongoing operations. The requirement for RFI control is presented, with brief reference to the more traditional methods used by other Radio Telescope observatories. The new approach is then presented, based on methods used in the engineering field of Logistic Engineering. Three case studies are used to illustrate how the approach can be applied. Finally, recommendations are made on how the approach can be implemented for new Radio Telescope projects. / AFRIKAANSE OPSOMMING: ‘n Metodolgie word ontwikkel vir die beheer van die groot aantal Radiofrekwensiesteurings oortreders by ‘n nuwe Radio Teleskoop terrein, soos die Suid Afrikaanse terrein wat huidiglik in die Karoo ontwikkel word. Die metodolgie geld beide gedurende konstruksie en gedurende bedryf. Die behoefte vir RFS beheer word aangebied, met kortlikse melding van die meer tradisionele metodes wat ander Radio Teleskoop Sterrewagte gebruik. ‘n Nuwe aanslag, gebaseer op die metodolgieë van Logistieke Ingenieurswese, word dan aangebied. Drie gevallestudies wys hoe hierdie nuwe aanslag toegepas kan word. Laastens word aanbevelings gemaak om hierdie nuwe aanslag met nuwe Radio Teleskoop projekte te implimenteer.

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