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Microwave Photonics(MWP) has been defined as the study of photonic devices which operate at microwave frequencies and also their applications to microwave and optical systems. One or more electrical signals at microwave frequencies are transported over the optic link ,with electrical to optical and optical to electrical conversion on the transmission and receiving side respectively. The key advantages of microwave photonic links over conventional electrical transmission systems such as coaxial cables or waveguides ,includes reduced size, weight and cost, immunity to electromagnetic interference ,low dispersion and high data transfer capacity. Integrated Optics is the name given to a new generation of opto-electronic systems in which the familiar wires and cables are replaced by light-waveguiding optical fibers, and conventional integrated circuits are replaced by optical integrated circuits (OICs).Microwave Photonics with photonic integration can add the benefits of reduction in system size, losses, short path lengths leading to more efficient cost effective systems. In this thesis, a new approach for using 1-D linear arrays of curved waveguides as delay lines is presented. We propose a design for a passive phase shifter obtained by curved waveguide delay lines. The modulated RF signal obtains the phase shift in the optical domain which is transferred to the RF signal by heterodyning techniques .This phase shift is independent of the RF frequency and hence the Beam squinting which occurs in the conventional RF phase shifter systems is avoided in the proposed system. Switching between different lengths of the bent/curved waveguides can produce variable phase shifts ranging from 0 to 2 radians. The use of curved waveguides for delay generation and optimization of various parameters are the main topics of the research problem. The need for delay line is large and most of these were implemented previously using long optical fiber cables. More precise delays could be obtained by using waveguide delay lines as compared to fiber delay lines. Waveguides paves way for design in smaller dimensions ranging from m to nm in integrated optics. The differential phase shift for a signal propagating in a waveguide from waveguide theory is given as which clearly indicates that the differential phase shifts could be obtained in accordance with differential path lengths Δl with β as the propagation constant. S-bend waveguide sections of different lengths along with straight waveguide as reference for each section are employed. The phase delay is passively obtained by a differential path length change, where various phase shift values can be obtained by switching between different differential path lengths. Since the optical phase delay generated is in- dependent of the input RF frequency. A shift in the RF frequency, at the input will not change the phase or beam pointing angle when the phase shifter is employed for beam pointing in case of Phased Array Antenna applications. A 1-bit phase shifter is the firrst step in the design which could be further extended to n-bit phase shifter. Here 1-bit or n-bit ,is one where n can take any integer value. Each bit is composed of a reference phase signal pathway and a delayed phase signal pathway. When the optical signal goes every single bit through the reference phase the phase shift is ‘0’ radians ,the other is through the delayed path which is . For every n-bit, 2n delays can be obtained. For the 1-bit,2 delays are obtained. Switching between the path lengths is done using the directional coupler switches. Th optimization of different parameters of the S-bend waveguide delay line has been realized and studied. The design and optimisation of a 1-bit optical RF phase shifter is discussed which could be extended to n-bit phase shifters. These S-bends are studied analytically. Beam Propagation Method (BPM)is employed for modeling and simulation of the proposed device. An interferometric configuration is considered for practical measurement of optical phase. In this configuration the phase change is translated into amplitude or intensity measurement. One of the arms of the Maczehdner Interferometer has no path length change while the other arm has an S-bend structure which provides the path length difference as compared to the reference path, and hence produces the necessary phase shift at the output of the interferometer as required. By changing the path length difference between the two arms of the interferometer ,a change in intensity is produced at the output of the interferometer. In this study, integrated optic curved waveguide delay line phase shifters are designed and analyzed, considering the Titanium Di used Lithium Niobate Technology. This is because it has good electro-optic properties necessary for designing switches used for switching between delay segments. Practical parameters that can be fabricated are employed in the design and simulation studies reported here. Fabrication is also done using the Lithium Niobate Technology. However the fabrication studies are excluded from the main stream, as further fabrication studies are necessary to realise the actual devices de- signed. The fabrication aspects are left as scope for further development. The fabricated devices are shown as appendix to the thesis. Organisation of the thesis Chapter 1 gives the introduction to the fields of Microwave Photonics and Integrated optics and its applications. Chapter 2discusses the curved waveguide theory and design with coverage of materials and methods employed in the proposed system. Chapter 3 discusses the different types of delay lines and the design of the 1-bit phase shifter which can be extended to the design of a n-bit phase shifter with both analytical and simulation results. Chapter 4 discusses the method of phase measurement for the n-bit phase shifter and the possible applications where the phase shifter could be employed. Chapter 5 discusses conclusions and future work in the proposed area of work. Appendix A discusses the loss calculations for the Cosine S-bend waveguide. Appendix B gives the fabrication details. The references form the end part of the thesis.

Microwave signal processing in the optical domain is investigated in this thesis. Two signal processors including an all-optical fractional Hilbert transformer and an all-optical microwave differentiator are investigated and experimentally demonstrated. Specifically, the photonic-assisted fractional Hilbert transformer with tunable fractional order is implemented based on a temporal pulse shaping system incorporating a phase modulator. By applying a step function to the phase modulator to introduce a phase jump, a real-time fractional Hilbert transformer with a tunable fractional order is achieved. The microwave bandpass differentiator is implemented based on a finite impulse response (FIR) photonic microwave delay-line filter with nonuniformly-spaced taps. A microwave bandpass differentiator based on a six-tap nonuniformly-spaced photonic microwave delay-line filter with all- positive coefficients is designed, simulated, and experimentally demonstrated. The reconfigurability of the microwave bandpass differentiator is experimentally investigated. The employment of the differentiator to perform differentiation of a bandpass microwave signal is also experimentally demonstrated.

Microwave signal processing in the optical domain is investigated in this thesis. Two signal processors including an all-optical fractional Hilbert transformer and an all-optical microwave differentiator are investigated and experimentally demonstrated. Specifically, the photonic-assisted fractional Hilbert transformer with tunable fractional order is implemented based on a temporal pulse shaping system incorporating a phase modulator. By applying a step function to the phase modulator to introduce a phase jump, a real-time fractional Hilbert transformer with a tunable fractional order is achieved. The microwave bandpass differentiator is implemented based on a finite impulse response (FIR) photonic microwave delay-line filter with nonuniformly-spaced taps. A microwave bandpass differentiator based on a six-tap nonuniformly-spaced photonic microwave delay-line filter with all- positive coefficients is designed, simulated, and experimentally demonstrated. The reconfigurability of the microwave bandpass differentiator is experimentally investigated. The employment of the differentiator to perform differentiation of a bandpass microwave signal is also experimentally demonstrated.

Advancement in cryptography over the past few decades has enabled a spectrum of security mechanisms and protocols for many applications. Despite the algorithmic security of classic cryptography, there are limitations in application and implementation of standard security methods in ultra-low energy and resource constrained systems. In addition, implementations of standard cryptographic methods can be prone to physical attacks that involve hardware level invasive or non-invasive attacks. Physical unclonable functions (PUFs) provide a complimentary security paradigm for a number of application spaces where classic cryptography has shown to be inefficient or inadequate for the above reasons. PUFs rely on intrinsic device-dependent physical variation at the microscopic scale. Physical variation results from imperfection and random fluctuations during the manufacturing process which impact each device’s characteristics in a unique way. PUFs at the circuit level amplify and capture variation in electrical characteristics to derive and establish a unique device-dependent challenge-response mapping. Prior to this work, PUF implementations were unsuitable for low power applications and vulnerable to wide range of security attacks. This doctoral thesis presents a coherent framework to derive formal requirements to design architectures and protocols for PUFs. To the best of our knowledge, this is the first comprehensive work that introduces and integrates these pieces together. The contributions include an introduction of structural requirements and metrics to classify and evaluate PUFs, design of novel architectures to fulfill these requirements, implementation and evaluation of the proposed architectures, and integration into real-world security protocols. First, I formally define and derive a new set of fundamental requirements and properties for PUFs. This work is the first attempt to provide structural requirements and guideline for design of PUF architectures. Moreover, a suite of statistical properties of PUF responses and metrics are introduced to evaluate PUFs. Second, using the proposed requirements, new and efficient PUF architectures are designed and implemented on both analog and digital platforms. In this work, the most power efficient and smallest PUF known to date is designed and implemented on ASICs that exploits analog variation in sub-threshold leakage currents of MOS devices. On the digital platform, the first successful implementation of Arbiter-PUF on FPGA was accomplished in this work after years of unsuccessful attempts by the research community. I introduced a programmable delay tuning mechanism with pico-second resolution which serves as a key component in implementation of the Arbiter-PUF on FPGA. Full performance analysis and comparison is carried out through comprehensive device simulations as well as measurements performed on a population of FPGA devices. Finally, I present the design of low-overhead and secure protocols using PUFs for integration in lightweight identification and authentication applications. The new protocols are designed with elegant simplicity to avoid the use of heavy hash operations or any error correction. The first protocol uses a time bound on the authentication process while second uses a pattern-matching index-based method to thwart reverseengineering and machine learning attacks. Using machine learning methods during the commissioning phase, a compact representation of PUF is derived and stored in a database for authentication.

This thesis describes the architecture and implementation of a novel 10-bit hybrid Analog to Digital Converter using Flash and Delay Line concepts. Flash ADCs employ power hungry comparators which increase the overall power consumption of a high resolution ADC. High resolution flash also requires precision analog circuit design. Delay line ADCs are based on digital circuits and operate at low power. Both Flash based ADCs and delay line based ADCs can be used to get a fast analog to digital conversion, but with limited resolution. These two approaches are combined to achieve a 10-bit resolution (4 bits using Flash and 6 bits using delay line) without compromising on speed and maintaining low power operation. Low resolution of Flash also helps in reducing the analog circuit design complexity of the voltage comparators. The ADC was capable of running at 100M samples/s, with an ENOB of 8.82 bits, consuming 8.59mW at 1.8V. / text

Microwave signal processing in the optical domain is investigated in this thesis. Two signal processors including an all-optical fractional Hilbert transformer and an all-optical microwave differentiator are investigated and experimentally demonstrated. Specifically, the photonic-assisted fractional Hilbert transformer with tunable fractional order is implemented based on a temporal pulse shaping system incorporating a phase modulator. By applying a step function to the phase modulator to introduce a phase jump, a real-time fractional Hilbert transformer with a tunable fractional order is achieved. The microwave bandpass differentiator is implemented based on a finite impulse response (FIR) photonic microwave delay-line filter with nonuniformly-spaced taps. A microwave bandpass differentiator based on a six-tap nonuniformly-spaced photonic microwave delay-line filter with all- positive coefficients is designed, simulated, and experimentally demonstrated. The reconfigurability of the microwave bandpass differentiator is experimentally investigated. The employment of the differentiator to perform differentiation of a bandpass microwave signal is also experimentally demonstrated.

Microwave signal processing in the optical domain is investigated in this thesis. Two signal processors including an all-optical fractional Hilbert transformer and an all-optical microwave differentiator are investigated and experimentally demonstrated. Specifically, the photonic-assisted fractional Hilbert transformer with tunable fractional order is implemented based on a temporal pulse shaping system incorporating a phase modulator. By applying a step function to the phase modulator to introduce a phase jump, a real-time fractional Hilbert transformer with a tunable fractional order is achieved. The microwave bandpass differentiator is implemented based on a finite impulse response (FIR) photonic microwave delay-line filter with nonuniformly-spaced taps. A microwave bandpass differentiator based on a six-tap nonuniformly-spaced photonic microwave delay-line filter with all- positive coefficients is designed, simulated, and experimentally demonstrated. The reconfigurability of the microwave bandpass differentiator is experimentally investigated. The employment of the differentiator to perform differentiation of a bandpass microwave signal is also experimentally demonstrated.

En combinant des techniques de microscopie et de spectroscopie, il est possible de réaliser des images résolues spectralement. Ces images apportent des réponses à de nombreux problèmes en chimie, biologie, et médecine. La diffusion Raman cohérente (CRS) s'est révélée capable de surpasser la diffusion Raman spontanée dans l'analyse chimique d'échantillons, en offrant une meilleure résolution spatiale et un temps d'acquisition plus faible. La vitesse d'acquisition de l'information spectrale demeure toutefois un facteur limitant en imagerie CRS, et de nombreuses recherches se concentrent sur le développement de nouvelles méthodes d'acquisition. Le présent travail s'inscrit dans cette démarche. En combinant la diffusion Raman stimulée (une branche de la CRS), la focalisation spectrale d'impulsions optiques, ainsi qu'une ligne à délai acousto-optique, nous réalisons les premières mesures à de telles vitesses d'acquisition. Le cadre théorique, technologique, ainsi que l’ingénierie nécessaire pour parvenir à ce résultat sont détaillés. Cette technique d'acquisition rapide est illustrée par le suivi de réaction chimique, le contrôle qualité pharmaceutique, en biologie, et en histologie / Combining microscopy and spectroscopy, one can achieve spectrally resolved imaging, and provide a solution to various chemical, biological, or medical challenges. Coherent Raman scattering (CRS) has proven extremely valuable in providing chemical information, with a higher resolution and shorter acquisition time than spontaneous Raman scattering. The acquisition rate of the spectral information from a sample remains the limiting factor of CRS imaging, and several experimental schemes are being investigated to push the technology toward higher imaging frame rates. This work develops one such scheme. Combining stimulated Raman scattering (a CRS technique), spectral focusing with chirped pulses, and a fast acousto-optic delay line, we achieved unprecedented spectral acquisition rates. The theoretical, technological, and engineering frameworks enabling such acquisition are described in details. The application to pharmaceutical quality control, time resolved chemical transformations, biology, and histology are demonstrated

<p>Position sensitive detectors represent a class of particle detectors widely used in high-energy physics, astrophysics, biophysics and medicine for imaging the spatial distribution of various radioactive sources. In recent years, a new class of gas based detectors, so-called micropattern gas detectors (MPGDs), has emerged. While modern MPGDs rival solid state detectors in terms of spatial and temporal resolution, their cost of production is significantly lower. A Thick Gaseous Electron Multiplier (THGEM) imaging detector, with a two-dimensional delay line readout, has been constructed as a concept for a large area imaging detector with reasonable spatial resolution. The delay line based THGEM imaging detector is robust, easy to manufacture and cost effective alternative to direct readout techniques which frequently employ a large number of channels. Featuring an active area of 40 x 40 mm<strong>2</strong>, the prototype has been constructed using two 0.4 mm THGEMs and successfully operated in a low pressure, propane based, gas mixture. Two sets of orthogonal electrodes, connected to individual delay lines, serve as a two-dimensional anode readout. Adjacent electrodes are separated by approximately 3.4 ns of time delay and allow the interaction position to be calculated by measuring the time difference between delay line output signals corresponding to a common axis. Using modern field programmable gate arrays (FPGAs), a time-to-digital (TDC) data acquisition (DAQ) system has been developed. The TDC DAQ performs the position reconstruction algorithm and is capable of continuous event rates up to 1.8 MHz. The imaging capabilities of the detector have been assessed using a collimated alpha source and a wide X-ray beam. Under these aforementioned conditions, the detector was able to successfully resolve 1 mm diameter holes spaced 3 mm apart. With higher operating pressures, and using Xenon based gas mixture, it is expected the imaging detector should achieve sub-mm spatial resolution. The investigations presented in this thesis serve as a framework for the development of future THGEM imaging detectors.</p> / Doctor of Philosophy (PhD)