To solve these issues, in this thesis the consistent effort in developing a quick tools assisted IC design platform is presented. First, a reconfigurable solution is proposed for some analog/mixed-signal (AMS) system which requires flexibility to a certain extent, such as a reconfigurable RFID solution for different communicating distances. Second, for further demand of increasing the flexibility, a novel approach for ADA is presented, which provides a highly automatic design flow for analog circuits to realize the "SPEC (Specification) in, GDS out" goal. Considering all kinds of higher order effects and uncertainties under deep submicron or even more advanced technologies, reliable design and fastness in processing are the two major concerns instead of the traditional pure optimization for best performance. To get a good balance among performance, reliability and turnaround time, an Application-Specific design flow with in-built knowledge-based algorithms is applied to deal with ADA issues under advanced technologies, which can quickly provide a reliable design with performance good enough to meet the SPECs for common use. / Unlike the highly automatic flow for digital circuits design, analog design automation (ADA) is still far from mature. For mixed-signal applications, analog circuit occupies only a small part on the layout, but the design requires a considerable amount of time and effort, making ADA extremely attractive. However, there are a lot more considerations to cover in analog design flow than its digital counterparts. In addition, the ever downscaling IC means analog circuits have to face more and more small-size effects, insufficient modelings, and the inaccuracy of classic formulas, which are quite difficult to handle. To solve the problem, various tools and methods have been proposed, but all in a digital-like flow, which are trying to develop general algorithms to realize circuit and layout synthesis. Up to now there is still a lot of problems. / Hong, Yang. / Adviser: C.S. Choy. / Source: Dissertation Abstracts International, Volume: 73-04, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2011. / Includes bibliographical references (leaves 140-150). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.

However, the proposed receiver and channel selection scheme still suffer from the mismatches picked up during RF-to-IF conversion. Therefore, a system called phase and amplitude mismatch cancellers is adopted to deal with the problem. Existing implementations neglected several critical behaviors of the cancellers, and provide image rejection ratios (IRR) ranging from 50dB to 65dB only. These behaviors include (i) arithmetic underflow, (ii) angular obscurity and (iii) spurious intermodulation products (IMD) produced by cancellers. We analyzed them and established several design rules, by which a far better IRR of at least 82.5dB was achieved. The system makes the proposed receiver and channel selection method feasible. / In traditional receivers involving intermediate frequency (IF), two different RF channels, Signal and Image, are converted to the same IF and overlap with each other. The Signal is always wanted with the Image eliminated, so each RF LO frequency can only select one RF channel. By digital low-IF, the IF-to-baseband conversion can be configured so that either channel can be selected, then each RF LO frequency can select two RF channels. This enhanced channel selection scheme can effectively reduce the number of LO frequency locations by half as well as the requirements of RF PLL frequency synthesizer. An existing approach makes use of configurable sampling scheme to achieve the same aim, but its use of analog sampling circuits results in phase and amplitude mismatches, from which the performance of image rejection suffers. Digital low-IF does not have this problem, since no mismatches are introduced to the signals after digitization. / The proposed digital low-IF Weaver receiver, together with the enhanced channel selection scheme and the phase and amplitude mismatch cancellers, are demonstrated to be feasible by a multi-band multi-mode receiver prototype supporting GSM900 and WCDMA. / The receiver architecture proposed in this thesis makes use of Weaver architecture with digital low-IF. Its flexibility allows for any operations to be performed on the digitized signals, as well as the enhanced channel selection scheme proposed in this thesis. / Chan Pak Kee. / "September 2007." / Adviser: Chiu Sing Choy. / Source: Dissertation Abstracts International, Volume: 69-08, Section: B, page: 4924. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (p. 152-162). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.

Au-Yeung Chung-Fai. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2003. / Includes bibliographical references (leaves 85-91). / Abstracts in English and Chinese. / Abstract --- p.i / Acknowledgments --- p.iii / Contents --- p.iv / Chapter Chapter 1 --- Introduction --- p.1 / Chapter Chapter 2 --- Basic Theory of Mixer --- p.6 / Chapter 2.1 --- Definition of mixer's electrical parameters --- p.8 / Chapter 2.2.1 --- Conversion gain --- p.8 / Chapter 2.2.2 --- Port-to-port isolation --- p.8 / Chapter 2.2.3 --- Noise figure --- p.9 / Chapter 2.2.4 --- 1-dB compression point (P1dB) --- p.11 / Chapter 2.2.5 --- 2nd order intercept point (IP2) --- p.11 / Chapter 2.2.6 --- 3rd order intercept point (IP3) --- p.12 / Chapter 2.2.7 --- Blocking dynamic range (BDR) --- p.12 / Chapter 2.2.8 --- Spurious free dynamic range (SFDR) --- p.12 / Chapter 2.2 --- Review of mixer architectures --- p.13 / Chapter 2.2.1 --- Diode mixer --- p.13 / Chapter 2.2.2 --- Dual-gate mxer --- p.14 / Chapter 2.2.3 --- Singly balanced mixer --- p.15 / Chapter 2.2.4 --- Doubly balanced dual-gate mixer --- p.16 / Chapter 2.2.5 --- Gilbert cell mixer --- p.18 / Chapter Chapter 3 --- CMOS Doubly Balanced Dual-Gate Mixer Design --- p.20 / Chapter 3.1 --- Design and Analysis --- p.20 / Chapter 3.1.1 --- Principle of operation --- p.20 / Chapter 3.1.2 --- Doubly balanced dual-gate mixer --- p.23 / Chapter 3.1.3 --- Common source output buffer --- p.25 / Chapter 3.1.4 --- Design example and simulation results --- p.26 / Chapter 3.2 --- IC Layout --- p.29 / Chapter 3.2.1 --- Multi-fingers transistor --- p.29 / Chapter 3.2.2 --- Matched transistor --- p.31 / Chapter 3.2.3 --- Match resistor --- p.32 / Chapter 3.2.4 --- Layout of CMOS doubly balanced dual-gate mixer --- p.33 / Chapter Chapter 4 --- Review of Mixer Linearization Techniques --- p.34 / Chapter 4.1 --- Source degeneration --- p.34 / Chapter 4.2 --- Feed-forward system --- p.36 / Chapter 4.3 --- Predistortion --- p.38 / Chapter 4.4 --- Difference-frequency (low-frequency) injection technique --- p.41 / Chapter Chapter 5 --- Mixer Linearization 一 Low Frequency Signal Injection --- p.44 / Chapter 5.1 --- Mixer's linearity --- p.44 / Chapter 5.2 --- Low-frequency signal injection method --- p.46 / Chapter 5.2.1 --- Single-injection scheme --- p.49 / Chapter 5.2.2 --- Dual-injection scheme --- p.50 / Chapter 5.2.3 --- Effect of gain error --- p.51 / Chapter 5.2.4 --- Bandwidth lim itation --- p.52 / Chapter Chapter 6 --- Experiments and Results --- p.55 / Chapter 6.1 --- CMOS doubly balanced dual-gate mixer --- p.55 / Chapter 6.1.1 --- Conversion gain --- p.56 / Chapter 6.1.2 --- Port-to-port isolation --- p.57 / Chapter 6.1.3 --- No ise figure --- p.60 / Chapter 6.1.4 --- 1-dB compression point --- p.61 / Chapter 6.1.5 --- 3rd order intercept point --- p.62 / Chapter 6.2 --- Low-frequency signal injection method --- p.63 / Chapter 6.2.1 --- Measurement result: single-injection scheme --- p.64 / Chapter 6.2.2 --- Measurement result: dual-injection scheme --- p.66 / Chapter Chapter 7 --- Conclusions and Recommendations for Future Work --- p.68 / Chapter 7.1 --- Conclusions --- p.68 / Chapter 7.2 --- Recommendations for future work --- p.69 / Appendix --- p.70 / Chapter A1 --- CMOS technology --- p.70 / Chapter A1.1 --- MOSFET structure --- p.70 / Chapter A1.2 --- CMOS n-well process --- p.71 / Chapter A1.3 --- MOSFET device modeling --- p.74 / Chapter A1.4 --- Channel length modulation --- p.78 / Chapter A1.5 --- Body effect --- p.78 / Chapter A2 --- Mixer's nonlinearity analysis --- p.79 / Chapter A2.1 --- First-order effect --- p.79 / Chapter A2.2 --- Second-order effect --- p.80 / Chapter A2.3 --- Third-order effect --- p.81 / Chapter A2.4 --- Nonlinear IF spectrum --- p.82 / Chapter A3 --- Artificial IMD3 produced by low-frequency signal injection --- p.83 / Author's Publication List --- p.85 / References --- p.86

Orientador: Jorge Muniz Junior / Coorientador: José Arnaldo Barra Montevechi / Banca: Valério Pamplona Salomon / Banca: Luis Alberto Ducan Rangel / Resumo: A tecnologia de Radio Frequency Identification (RFID) tornou-se um tema importante desde 2006, quando vários autores começaram a avaliá-la. A aplicação de RFID para processos industriais tem uma abordagem estratégica, objetivando a melhoria da satisfação dos clientes e criar novas oportunidades de negócios, bem como uma abordagem operacional com foco na eficiência operacional e na flexibilidade dos processos. A tecnologia é aplicada na logística e nos demais processos da cadeia de suprimentos com o objetivo do rastreamento dos materiais, aumento de visibilidade, aumento da eficiência operacional, redução dos desvios do processo e aumento da acessibilidade do inventário. Neste cenário, a presente dissertação tem como objetivo a avaliação de projetos logísticos aplicados à indústria aeronáutica brasileira com o uso do AHP - Analytic Hierarchy Process com ratings - passando pela identificação e avaliação das características que motivam e restringem a utilização da tecnologia através de uma revisão da literatura e pesquisa de campo / Abstract: Research on Radio Frequency Identification technology (RFID) has become an important issue since 2006 and several authors have begun to assess this technology. The application of RFID to industrial processes has a strategic approach, seeking to improve customer satisfaction and new business opportunities, and has an operational approach focusing on operational efficiency and flexibility of the processes. There is a great application of RFID in logistics, warehouse and supply chain processes seeking tracking materials, increase supply chain visibility, labor savings, shrinkage reduction and inventory visibility. In this scenario, this paper aims to evaluate logistics projects applied to the brazilian aircraft industry using the AHP - Analytic Hierarchy Process with ratings, in addition to the identification and evaluation of the characteristics that motivate and restrict the use of technology through a literature review and a survey / Mestre

Sze, Wai Kit. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references (leaves 77-83). / Abstracts in English and Chinese. / Abstract --- p.i / Acknowledgement --- p.vi / Chapter 1 --- Introduction --- p.1 / Chapter 2 --- Background and Related Work --- p.8 / Chapter 3 --- RFID Tag-set Cardinality estimation based on a Two-parameter implicit Channel Model --- p.13 / Chapter 3.1 --- System Model --- p.14 / Chapter 3.2 --- Number of Empty Slots Observed by the Reader --- p.16 / Chapter 3.3 --- Estimator Accuracy and Performance Analysis --- p.25 / Chapter 3.4 --- Results and Discussions --- p.32 / Chapter 3.5 --- Chapter Summary --- p.41 / Chapter 4 --- RFID Tag-set Cardinality estimation over Unknown Channel --- p.42 / Chapter 4.1 --- System Model --- p.43 / Chapter 4.2 --- Baseline: The Union-based approach --- p.45 / Chapter 4.2.1 --- Motivation --- p.46 / Chapter 4.2.2 --- Union Algorithm --- p.46 / Chapter 4.2.3 --- Analysis of the Union algorithm --- p.47 / Chapter 4.3 --- "Probabilistic Tag-counting over Lossy, Unknown channels via the Mh model" --- p.52 / Chapter 4.3.1 --- "Novel Interpretation of Mh for RFID Counting over Lossy, Unknown Channels" --- p.52 / Chapter 4.3.2 --- The Moment Estimator --- p.55 / Chapter 4.3.3 --- Sample Coverage Estimator --- p.57 / Chapter 4.3.4 --- Estimating the overall Tag population t --- p.59 / Chapter 4.4 --- Performance Validation and Comparison --- p.62 / Chapter 4.5 --- Chapter Summary --- p.65 / Chapter 5 --- Conclusions and Future Work --- p.73 / Chapter A --- Proof of Equation (3.6) in Chapter 3 --- p.75 / Bibliography --- p.77

Two-dimensional spatially selective radiofrequency (2DRF) pulse is a type of excitation radiofrequency (RF) pulse in magnetic resonance imaging (MRI) which selects and excites spins in two dimensions simultaneously. Due to its extra selectivity on the second dimension compared with conventional one-dimensional RF pulse, 2DRF pulse could realize reduced field of view (rFOV) imaging. 2DRF-enabled rFOV imaging can accelerate imaging speed, and improve image quality significantly. Advances of 2DRF pulse have been achieved in recent years. However, its wide application in routine clinical practice is hindered by rigid design of 2DRF pulse, the long pulse duration, the inflexibility in excitation pattern, and the user-unfriendliness for non-specialists. The objective of this thesis work is to develop a high-efficient and user-friendly 2DRF pulse to improve its usability and efficiency in routine clinical practice, especially for non-specialists. Finally, the feasibility and applicability of the developed 2DRF pulse was verified in human spine T₁ₚ MR imaging and chemical exchange saturation transfer (CEST) imaging. / A high-low echo planar (EP) 2DRF pulse was first developed to realize rFOV imaging. Developed 2DRF pulse was evaluated in both phantom and human brain. The advantages of being robust to moderate gradient system delay and higher image signal to noise ratio (SNR) of the proposed 2DRF pulse were characterized by the better excitation profiles compared with conventional EP 2DRF pulse sequence. Additionally, the flexibility of the developed 2DRF pulse was verified by the constant image qualities and excitation profiles at different on-line setups. These results demonstrated the feasibility and user-friendliness of the high-low EP 2DRF pulse and revealed its potential application in routine clinical practice. / The high-low EP 2DRF pulse was then incorporated into T₁ₚ sequence to realize rFOV spine T₁ₚ imaging. Quantitative T₁ₚ imaging is time consuming in particular for high spatial resolution images obtained with high spin-lock frequency (FSL) though fast acquisition techniques could be employed. In addition, spine T₁ₚ imaging is vulnerable to the artifact induced by respiration and fat-water chemical shift. Reduced field of view in phase encoding (PE) direction helps to shorten the acquisition time, while preserving the SNR and resolution. The respiration artifact can be eliminated as no spin in chest or abdomen is excited. The 2DRF-enabled rFOV T₁ₚ imaging shortened scan time to the half and minimized respiration artifacts. rFOV CEST imaging was realized by the high-low EP 2DRF pulse. The feasibility of 2DRF pulse enabled rFOV CEST imaging was demonstrated. / 二維空間選擇射頻脈衝（2DRF）是一種磁共振成像中的激發脈衝。它能夠在兩個維度上同時地選擇性激發自旋。和傳統的一維選擇射頻脈衝相比，2DRF 在另一維度上額外的選擇能力使之能夠實現小視域成像。2DRF小視域成像能夠大幅加快成像速度以及提高圖像質量。近年來，2DRF的理論和實驗成果日益豐碩，但2DRF的廣泛臨床應用受到了其相對複雜的設計，較長的激發時間，不夠靈活的激發模式，對組織磁敏感性的過於靈敏以及對於非專業人士的難以操控性等諸多因素的阻礙。這篇碩士論文所述工作的目的是開發一種高效以及易操控的2DRF,以提高它在臨床應用中的實用性和易用性。而後，在人體脊柱T1ₚ磁共振成像和化學轉移飽和交換（CEST）成像技術中，驗證了所提出的2DRF的可行性和適用性。 / 一種高-低回波平面2DRF被首次提出并用於實現小視域成像。這種2DRF在水模和人體腦部成像中得以檢驗。相較於一般的平面回波2DRF，其具有對梯度線圈系統延遲的魯棒性，以及較高的信噪比。這些優勢體現于較好的激發圖樣中。此外，此種2DRF的靈活性在多種設定中取得的穩定的圖像質量和激發圖樣中得到體現。 / 所提出的高-低回波平面2DRF隨後與T1ₚ磁共振成像序列相結合實現了小視域脊柱T1ₚ成像。量化T1ₚ成像比較費時，特別是在使用較高自旋鎖定頻率或者較高的成像分辨率時。此外，脊柱T1ₚ成像容易受到呼吸運動以及水脂化學位移導致的偽影的影像。小視域成像在相位編碼方向上減少了成像範圍，從而在保證圖像信噪比和分辨率的同時減少了圖像採集時間。由於沒有腹部的自選電子被激發，呼吸運動偽影也得以消除。小視域脊柱T1ₚ成像大幅減少成像時間至常規時間的一半以下且最大程度地消除了呼吸運動偽影。通過應用這種2DRF,小視域化學轉移飽和交換轉移成像隨後也得以實現。在研究中，這種成像技術的可行性得到了證明。 / Zhang, Qinwei. / Thesis M.Phil. Chinese University of Hong Kong 2014. / Includes bibliographical references (leaves 69-79). / Abstracts also in Chinese. / Title from PDF title page (viewed on 11, October, 2016). / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only.

Submitted in fulfilment of the academic requirements for the degree of Doctor of Philosophy (Ph.D.) in Engineering, in the School of Electrical and Information Engineering, Faculty of Engineering and the Built Environment, at the University of the Witwatersrand, Johannesburg, South Africa, 2017 / The continuous evolution of wireless communications technologies has increasingly imposed a burden on the use of radio spectrum. Due to the proliferation of new wireless networks applications and services, the radio spectrum is getting saturated and becoming a limited resource. To a large extent, spectrum scarcity may be a result of deficient spectrum allocation and management policies, rather than of the physical shortage of radio frequencies. The conventional static spectrum allocation has been found to be ineffective, leading to overcrowding and inefficient use. Cognitive radio (CR) has therefore emerged as an enabling technology that facilitates dynamic spectrum access (DSA), with a great potential to address the issue of spectrum scarcity and inefficient use. However, provisioning of reliable and robust communication with seamless operation in cognitive radio networks (CRNs) is a challenging task. The underlying challenges include development of non-intrusive dynamic resource allocation (DRA) and optimization techniques. The main focus of this thesis is development of adaptive channel assembling (ChA) and DRA schemes, with the aim to maximize performance of secondary user (SU) nodes in CRNs, without degrading performance of primary user (PU) nodes in a primary network (PN). The key objectives are therefore four-fold. Firstly, to optimize ChA and DRA schemes in overlay CRNs. Secondly, to develop analytical models for quantifying performance of ChA schemes over fading channels in overlay CRNs. Thirdly, to extend the overlay ChA schemes into hybrid overlay and underlay architectures, subject to power control and interference mitigation; and finally, to extend the adaptive ChA and DRA schemes for multiuser multichannel access CRNs. Performance analysis and evaluation of the developed ChA and DRA is presented, mainly through extensive simulations and analytical models. Further, the cross validation has been performed between simulations and analytical results to confirm the accuracy and preciseness of the novel analytical models developed in this thesis. In general, the presented results demonstrate improved performance of SU nodes in terms of capacity, collision probability, outage probability and forced termination probability when employing the adaptive ChA and DRA in CRNs. / CK2018

The Technical Testing and Analysis Center (TTAC) Group at Oak Ridge National Laboratory performs electromagnetic compatibility testing on various radiation detection units. These tests require remote viewing of the equipment’s display to monitor its compliance with national and international standards. The Commercial-Off-the-Shelf (COTS) camera equipment that is used to monitor the displays exhibits radio frequency susceptibilities causing issues when determining the actual susceptibilities of the device under test. In order to mitigate this issue, a COTS camera was placed in two common test positions and cycled through three angled orientations with various radio frequency shielding methods applied. The development of these shielding methods was investigated in this thesis. The goal was to reduce the number of susceptible frequencies. The reduction of susceptibilities would greatly increase the viewing capacity of the cameras during testing. The techniques discovered have allowed for other COTS camera equipment to be modified and used effectively during electromagnetic compatibility testing.

A dusty plasma is a mixture of electrons, ions, neutral gas atoms, and small particles of solid matter (dust). In a dusty plasma produced in the laboratory, dust particles gain a large electric charge from the other charged species, so that their interparticle interactions can be very strong. Frequently, the average interparticle potential energy is higher than the thermal kinetic energy of the dust particles, and in this case, they constitute a strongly coupled plasma. As with all strongly coupled plasmas, the dust particles can behave like typical solids or liquids. In this thesis, I report the results of dusty plasma experiments that are focused on the behavior of liquids. I use a so-called two-dimensional (2D) dusty plasma that consists of only a single horizontal layer of dust particles. Tracking each particle with video microscopy and image analysis methods allows the calculation of important liquid properties, like the viscosity coefficient. In Chapter 2, I describe an improved laser heating method for producing liquid-like conditions in a 2D dusty plasma. Two laser beams are scanned across the dust layer in a new pattern to increase the kinetic energy of the particles and melt the ground state crystalline lattice. The new scanning pattern improves the randomness of the resulting particle motion so that it more closely resembles that of a liquid in a thermal equilibrium. In Chapter 3, I report a viscosity measurement in a dusty plasma that is unaffected by the complicating effects of temperature nonuniformities and shear thinning. This measurement is enabled by an addition to my experimental apparatus that I also detail here. I find the viscosity to be significantly higher than in previous measurements, which I attribute to the avoidance of shear thinning. In Chapter 4, I present measurements of viscosity using the Green-Kubo method, and compare the results to those of my previous measurement. I find that the two methods yield viscosity values that differ by about 60%, over the entire temperature range attained in the experiment. Possible sources of this difference are evaluated. Finally, in Chapter 5, I report the first experimental confirmation of a theoretical expression describing the decay of time autocorrelation functions. This theoretical expression fits experimentally calculated autocorrelation functions within error bars, especially at short times when a simple exponential decay fails. I also propose an intuitive description wherein an observed transition in the autocorrelation function is due to the onset of collisional scattering.

A novel method is shown for fitting and/or validating electro-thermal models using pulsed I(V) measurements and pulsed I(V) simulations demonstrated using modifications of an available non-linear model for an LDMOS (Laterally Diffused Metal Oxide Semiconductor) device. After extracting the thermal time constant, good agreement is achieved between measured and simulated pulsed I(V) results under a wide range of different pulse conditions including DC, very short (<0.1%) duty cycles, and varied pulse widths between these extremes. A pulsed RF load-pull test bench was also assembled and demonstrated for a VDMOS (Vertically Diffused Metal Oxide Semiconductor) and an LDMOS power transistor. The basic technique should also be useful for GaAs and GaN transistors with suitable consideration for the complexity added by trapping mechanisms present in those types of transistors.