<p>In this thesis work, a design of RF down-conversion mixer for WLAN standard, such as Wi-Fi or Bluetooth is presented. The target technology is 0.35um CMOS process. Several mixer topologies are analyzed and simulated at the schematic level using the Cadence Spectre-RF software. The active double balanced mixer is chosen for the ultimate implementation. For this mixer simulation results from schematic level to layout level are presented and discussed in detail. </p><p>To build an RF front-end, the complete mixer is integrated with an available LNA block. The performance of the front-end is evaluated as well. The obtained simulation results satisfy the specification for Wi-Fi standard. </p><p>Since the RF front-end is designed for testability, the fault simulation is incorporated as well. So the performance of the front end is also evaluated for so called “spot defects”, typical of CMOS technology. They are modeled using resistive shorts or opens in the circuit.</p>

The IEEE 802.11a has become the mainstream protocol used in modern wireless communication system due to its high propagation rate of data (54 Mb/s). To meet high propagation rates, the communication devices used in IEEE 802.11a protocol usually present a high conversion gain and a high linearity (denoted as third order intercept point, IIP3). The IIP3 of conventional up- and down-conversion mixers are only about 0 dBm and -5 dBm, which fail to achieve a high propagation rate of data. This thesis utilizes the TSMC 0.18 &#x00B5;m CMOS technology to design and fabrication up- and down-conversion mixers with very high linearity for IEEE 802.11a application. The proposed high-linearity up-conversion mixer with 1.01 mm ¡Ñ 0.85 mm chip size and its wide bandwidth (5~6 GHz) is well suited for IEEE 802.11a application. To enhance the linearity and bandwidth, a transconductor stage with gm-boosted structure, a switch stgae with LO-body grounded structure and a load stage with shunt peaking structure are adopted in this research. Under 5.2/5.4/5.8 GHz operating frequencies, the implemented up-conversion mixer demonstrates a high conversion gain of 6.8/7.1/6.3 dB and a high linearity of 8.9/9/13.2 dBm, respectivly. In addition, a moderate consuming power (6.86 mW) of such mixer can be achieved at 1.2 V supply voltage. On the other hand, this thesis also designed and fabricated a high-linearity down-conversion mixer with chip size of 1.02 mm ¡Ñ 0.86 mm and 5.2 GHz center frequency. To improve the linearity and isolation and reduce the high-order noise, a transconductor stage with dual-gate structure and a load stage with RC-tank structure are adopted in this research. According to the EM-simulation resutls, the proposed down-conversion mixer presents a moderate conversion gain of 6 dB and a high linearity of 0.8 dBm. Additionly, a moderate consuming power (6.75 mW) of such mixer can be achieved at 1.8 V supply voltage.

In this thesis work, a design of RF down-conversion mixer for WLAN standard, such as Wi-Fi or Bluetooth is presented. The target technology is 0.35um CMOS process. Several mixer topologies are analyzed and simulated at the schematic level using the Cadence Spectre-RF software. The active double balanced mixer is chosen for the ultimate implementation. For this mixer simulation results from schematic level to layout level are presented and discussed in detail. To build an RF front-end, the complete mixer is integrated with an available LNA block. The performance of the front-end is evaluated as well. The obtained simulation results satisfy the specification for Wi-Fi standard. Since the RF front-end is designed for testability, the fault simulation is incorporated as well. So the performance of the front end is also evaluated for so called “spot defects”, typical of CMOS technology. They are modeled using resistive shorts or opens in the circuit.

The IEEE 802.11a has become the mainstream protocol used in modern wireless communication system due to its high propagation rate of data (54 Mb/s). To meet high propagation rates, the communication devices used in IEEE 802.11a protocol usually present a high conversion gain and a high linearity (denoted as third order intercept point, IIP3). The IIP3 of conventional up- and down-conversion mixers are only about 0 dBm and -5 dBm, which fail to achieve a high propagation rate of data. This thesis utilizes the TSMC 0.18 £gm CMOS technology to design and fabrication up- and down-conversion mixers with very high linearity for IEEE 802.11a application. The proposed high-linearity up-conversion mixer with 1.01 mm ¡Ñ 0.85 mm chip size and its wide bandwidth (5~6 GHz) is well suited for IEEE 802.11a application. To enhance the linearity and bandwidth, a transconductor stage with gm-boosted structure, a switch stgae with LO-body grounded structure and a load stage with shunt peaking structure are adopted in this research. Under 5.2/5.4/5.8 GHz operating frequencies, the implemented up-conversion mixer demonstrates a high conversion gain of 6.8/7.1/6.3 dB and a high linearity of 8.9/9/13.2 dBm, respectivly. In addition, a moderate consuming power (6.86 mW) of such mixer can be achieved at 1.2 V supply voltage. On the other hand, this thesis also designed and fabricated a high-linearity down-conversion mixer with chip size of 1.02 mm ¡Ñ 0.86 mm and 5.2 GHz center frequency. To improve the linearity and isolation and reduce the high-order noise, a transconductor stage with dual-gate structure and a load stage with RC-tank structure are adopted in this research. According to the EM-simulation resutls, the proposed down-conversion mixer presents a moderate conversion gain of 6 dB and a high linearity of 0.8 dBm. Additionly, a moderate consuming power (6.75 mW) of such mixer can be achieved at 1.8 V supply voltage.

In this thesis, simulations of two novel features of a serially cascaded micro-ring resonator are presented. The thesis firstly describes the simulation of a novel, silicon on insulator (SOI) method to determine the refractive index change of a covering analyte by the extraction of the refractive index change information in the time domain. Secondly a novel arrangement of the serially cascaded micro-rings has the effect of producing a null instead of a peak in the Vernier enhanced resonant spectrum. The null feature, as well as the enhanced sensitivity of the sensor, allows the sensor to be used as an intensity interrogating device. The development of these applications using ring resonator physics is achievable, out-of-lab, by the application of photonic software. Finite difference time domain (FDTD), beam propagation method (BPM), finite element(FE) and eigenmode expansion (EME) methods were all used in the simulated development of the sensor. As a result of the dual ring resonator arrangement, the temporal output undergoes a wavelength (or frequency) shift from the micrometre (or TeraHertz) to the centimeter (or GigaHertz) range of frequencies. This allows the refractive index information to become available for transmission in the cm wavelength range over a standard wireless network. The latter could be realized by integration of a photo-detector and antenna into the final design. The sensor output is invariant to any structural or temperature changes applied to both rings. Two sensors based on the same design, but having different fabrication methods, are simulated. Models of the rib and ridge structures are realized by using optical simulation software. The data obtained from these simulations are then used to plot the ring resonator outputs in MATLAB. The design can be applied for either bulk (homogeneous) or surface sensing. Only homogeneous sensing, in the form of a uniform refractive index cover change, is simulated in this thesis. The spectral sensitivity of the rib based design, without Vernier enhancement, is 87.65nmRIU-1, while the spectral sensitivity of the ridge waveguide, without Vernier enhancement, is 422nmRIU-1. The Vernier enhanced spectral sensitivity of the rib design is 6415nmRIU-1 and the limit of detection is 12.47x10-6 RIU. The temporal sensitivity of the ridge is 1.9418μsec RIU-1. The rib temporal sensitivity was not calculated but it is expected to be ~ five times less sensitive than the non Vernier enhanced ridge design. Titanium Nitride (TiN) heaters were also included over the coupling regions of the dual ring resonators. The effect of the heaters on the dual ring resonant wavelength and on the single ring spectral shift were also simulated using a multi-physics utility of the applied FEM and BPM software. With the heater at 1.28μm above the resonator coupling waveguides, a single ring spectral shift of 717pm was exhibited by this simulation. For the heater positioned at 250nm above the coupling waveguides, a single ring spectral shift of 2.89nm was exhibited. Finally the fabricated designs, which are based on the models of the simulation data, were characterized and the results compared to the predicted outputs generated by the models of the Temperature Invariant Modulated Output Sensor (TIMOS).

Spontaneous parametric down-conversion (SPDC) is a nonlinear optical process in which an incident field known as the pump interacts with a nonlinear crystal to produce two output fields known as signal and idler. Due to the conservation of energy and momentum, these output fields are entangled in the temporal and spatial degrees of freedom. The gain, which represents the strength of the interaction, increases in direct proportion to the strength of the pump field. In the low-gain regime, the generated field is an entangled two-photon state. This regime continues to be routinely employed in fundamental quantum optics experiments and quantum technologies. In the high-gain regime, the generated field is a multiphoton entangled state known as a bright squeezed vacuum. The goal of this thesis is to theoretically and experimentally characterize the spatial correlations present in high-gain SPDC. In order to characterize the spatial correlations between the generated fields, we utilize the Schmidt decomposition formalism. In this study, we examine the evolution of the Schmidt modes and spectrum with increasing pump amplitude. Our work shows that the Schmidt modes expand marginally in size, and the Schmidt spectrum narrows with respect to increasing gain. The narrowing of the Schmidt spectrum, as quantified by a decrease in the Schmidt number, indicates a gradual decrease in spatial entanglement.

Les propriétés structurales et de luminescence de couches minces de TiO2 et Y2O3 dopées terres rares (thulium, terbium et ytterbium) ont été étudiées en vue de les intégrer dans une cellule photovoltaïque comme couche de conversion spectrale du proche UV vers l’infrarouge afin d’en améliorer l’efficacité. Ces couches minces ont été synthétisées par dépôt chimique en phase vapeur à pression atmosphérique à l’aide de précurseurs organo-métalliques et assisté par aérosol (aerosol assisted MOCVD). Les couches minces sont partiellement cristallisées dès la synthèse (400°C pour le TiO2 en phase anatase, 540°C pour Y2O3 en phase cubique). Après traitement thermique la cristallisation est largement améliorée et la luminescence des ions dopant terres rares est obtenue dans les deux matrices oxydes. Le thulium émet dans une large bande située vers 800 nm et l’ytterbium vers 980 nm. Le terbium quand à lui émet dans une gamme située principalement dans le visible. Les spectres d’excitation ont montré que l’absorption des photons se fait via la matrice. En matrice TiO2 une efficacité de transfert d’énergie du Tm3+ vers l’Yb3+ de l’ordre de 20 % a été déterminée pour des teneurs de 0,8 % des deux dopants, ce qui correspond à la limite d’auto-extinction. Le rendement global mesuré est faible, nous avons montré que les causes probables de cette faible valeur sont le manque d’absorption des couches minces pour obtenir l’excitation de l’ion sensibilisateur ainsi que des processus de luminescence et de down conversion pas assez efficaces. / Structural and luminescence properties of rare-earth-doped (thulium, terbium and ytterbium) thin films of yttrium oxide and titanium oxide were studied as a down-converting layer from near-UV to infrared for integration in solar cells to improve their yield. These thin films were synthesized by chemical vapor deposition at atmospheric pressure with organo-metallic precursors and assisted by aerosol (aerosol assisted MOCVD). The thin films were partially crystallized as deposited (400°C in the anatase phase for TiO2 , 540°C in the cubic phase for Y2O3). After annealing the crystallization is greatly improved and the rare-earth ion luminescence is obtained in both oxide matrices. The thulium emits in a large band centered around 800 nm and the ytterbium at 980 nm. The terbium emits mainly in the visible range. Excitation spectra showed that the photon absorption occurs in the matrix. In the TiO2 matrix a transfer rate from Tm to Yb of 20 % was measured for doping of 0,8 % for both rare-earth, which corresponds to the quenching limit. The overall measured yield is low, we showed that the probable reasons were the thin films’ lack of absorption to obtain the excitation of the sensitizer ion and a low efficiency of luminescence and down-conversion processes.

International Telemetering Conference Proceedings / October 28-31, 1996 / Town and Country Hotel and Convention Center, San Diego, California / Aerospace Report No. TOR-0059(6110-01)-3, section 1.3.3 outlines the design and performance requirements of SGLS (Space Ground Link Subsystem) services. GDP Space Systems has developed a single card slot FSK (Frequency Shift Keying)/AM (Amplitude Modulation) demodulator. An application of this service is the US Air Force Satellite Command and Ranging System. The SGLS signal is tri-tone-FSK, amplitude modulated by a modified triangle wave at half the data rate. First generation FSK/AM demodulators had poor noise performance because the signal tones were filtered and processed at IF frequencies (65, 76 and 95 kHz). Second generation demodulators suffer from "threshold" due to non-linear devices in the signal path before the primary noise filtering. The GDP Space Systems demodulator uses a 0-Hz- IF topology and avoids both of these shortcomings. In this approach, the signal is first noncoherently down converted to baseband by linear devices, then it is filtered and processed. This paper will discuss the GDP 0-Hz-IF FSK/AM (SGLS) demodulator.

This thesis describes various methods for producing photon pairs from waveguides. It covers relevant topics such as waveguide coupling and phase matching, along with the relevant measurement techniques used to infer photon pair production. A new proposal to solve the phase matching problem is described along with two conceptual methods for generating entangled photon pairs. Photon pairs are also experimentally demonstrated from a third novel structure called a Bragg Reflection Waveguide (BRW). The new proposal to solve the phase matching problem is called Directional Quasi-Phase Matching (DQPM). It is a technique that exploits the directional dependence of the non-linear susceptiblity ($\chi^{(2)}$) tensor. It is aimed at those materials that do not allow birefringent phase-matching or periodic poling. In particular, it focuses on waveguides in which the interplay between the propagation direction, electric field polarizations and the nonlinearity can change the strength and sign of the nonlinear interaction periodically to achieve quasi-phasematching. One of the new conceptual methods for generating entangled photon pairs involves a new technique that sandwiches two waveguides from two differently oriented but similar crystals together. The idea stems from the design of a Michelson interferometer which interferes the paths over which two unique photon pair processes can occur, thereby creating entanglement in any pair of photons created in the interferometer. By forcing or sandwiching the two waveguides together, the physical space that exists in the standard Micheleson type interferometer is made non-existent, and the interferometer is effectively squashed. The result is that the two unique photon pair processes actually occupy the same physical path. This benefits the stability of the interferometer in addition to miniaturizing it. The technical challenges involved in sandwiching the two waveguides are briefly discussed. The main result of this thesis is the observation of photon pairs from the BRW. By analyzing the time correlation between two single photon detection events, spontaneous parametric down conversion (SPDC) of a picosecond pulsed ti:sapph laser is demonstrated. The process is mediated by a ridge BRW. The results show evidence for type-0, type-I and type-II phase matching of pump light at 783nm, 786nm and 789nm to down converted light that is strongly degenerate at 1566nm, 1572nm, and 1578nm respectively. The inferred efficiency of the BRW was 9.8$\cdot$10$^{-9}$ photon pairs per pump photon. This contrasts with the predicted type-0 efficiency of 2.65$\cdot$10$^{-11}$. This data is presented for the first time in such waveguides, and represents significant advances towards the integration of sources of quantum information into the existing telecommunications infrastructure.

This thesis presents a Hamiltonian formulation of the electromagnetic fields in structured (inhomogeneous) media of arbitrary dimensionality, with arbitrary material dispersion and absorption consistent with causality. The method is based on an identification of the photonic component of the polariton modes of the system. Although the medium degrees of freedom are introduced in an oscillator model, only the macroscopic response of the medium appears in the derived eigenvalue equation for the polaritons. For both the discrete transparent-regime spectrum and the continuous absorptive-regime spectrum, standard codes for photonic modes in nonabsorptive systems can easily be leveraged to calculate polariton modes. Two applications of the theory are presented: pulse propagation and spontaneous parametric down-conversion (SPDC). In the propagation study, the dynamics of the nonfluctuating part of a classical-like pulse are expressed in terms of a Schr\"{o}dinger equation for a polariton effective field. The complex propagation parameters of that equation can be obtained from the same generalized dispersion surfaces typically used while neglecting absorption, without incurring additional computational complexity. As an example I characterize optical pulse propagation in an Au/MgF$_2$ metallodielectric stack, using the empirical response function, and elucidate the various roles of Bragg scattering, interband absorption and field expulsion. Further, I derive the Beer coefficient in causal structured media. The SPDC calculation is rigorous, captures the full 3D physics, and properly incorporates linear dispersion. I obtain an expression for the down-converted state, quantify pair-production properties, and characterize the scaling behavior of the SPDC energy. Dispersion affects the normalization of the polariton modes, and calculations of the down-conversion efficiency that neglect this can be off by 100$\%$ or more for common media regardless of geometry if the pump is near the band edge. Furthermore, I derive a 3D three-wave group velocity walkoff factor; due to the interplay of a topological property with a symmetry property, I show that even if down-conversion is into a narrow forward cone, neglect of the transverse walkoff can lead to an overestimate of the SPDC energy by orders of magnitude.