The objective of this thesis was to develop novel technologies for measuring the physical characteristics of high-speed pulse trains, for use in performance monitoring applications. This thesis describes the development of three separate techniques that perform measurements in either the time domain, frequency domain or the phase space of the optical signal. The first section investigates phase-sensitive pulse measurement techniques. A high- resolution SHG-FROG apparatus was custom-designed to measure 40GHz RZ pulse trains, from which an operational characterisation of a Mach-Zehnder modulator (MZM) was realised. A numerical model of a nonlinear pulse compressor was developed to compress 40GHz RZ pulses from 8.5ps down to 3.4ps. These pulses were time-division multiplexed to 80GHz, and phase-retrievals of the 80GHz pulse trains were measured. A comparison between the techniques of SHG-FROG and linear spectrogram has been undertaken for 10GHz pulse sources, exposing SHG-FROG's weaknesses at this particular repetition rate. The second section investigates a simple, time-averaged, nonlinear detection technique. Two-photon absorption in a GaAs/InGaAs quantum-well laser diode was used to measure the duty cycle (and by extension, the pulse duration) of a range of pulse sources. This technique was further developed to measure the extinction ratio of NRZ pulse trains. Additionally, the pulse duration of a mode-locked laser source was measured using the nonlinear absorption in a 1-m length of As2Se3 Chalcogenide glass fiber. This demonstrates that the nonlinear properties of this glass may well find application in future instrumentation. The third section investigates the development of an ultra-high resolution swept heterodyne spectrometer. This spectrometer was used to spectrally-distinguish repetitive 8-bit NRZ patterns at 2.5Gbit/s. It was also used to measure the chirp parameter of an X-cut LiNbO3 MZM, revealing a chirp parameter of απ/2 < 0.1 across a modulation band- width of 250-2500MHz. Additionally, the distinctive CW spectrum of a DFB laser diode was measured. Analysis of the measured CW spectrum yielded a linewidth enhancement factor of α≃ 1.8 and also the relative intensity noise of the DFB laser diode.

L'objectif de l'instrument hétérodyne MAMBO (Mars Atmosphere Microwave Brightness Observer) est d'étudier et de cartographier l'atmosphère et la surface de la planète Mars, à partir d'observations radiométriques dans le domaine submillimétrique, couvrant la bande de fréquence 320-350 GHz. Prévu initialement pour être embarqué sur la mission Mars Premier Orbiter du CNES en 2007, la définition de l'instrument ainsi que les caractéristiques de la tête de réception hétérodyne sont présentées en première partie.<br />Le thème principal de la thèse concerne l'étude et la réalisation d'un mélangeur subharmonique à diodes Schottky planaires, constitutif de la tête de réception hétérodyne de l'instrument. Un modèle numérique du mélangeur a été conçu en couplant des simulations électromagnétiques tridimensionnelles et des simulations de circuits non-linéaires. Cette méthode de simulation a permis d'optimiser les structures guidantes et le circuit du mélangeur pour élargir au maximum la bande de fréquence instantanée, et réduire la puissance d'Oscillateur Local (OL) nécessaire au fonctionnement optimal de la paire de diodes. Les performances mesurées du prototype réalisé sont en accord étroit avec les résultats de simulations, avec une sensibilité à l'état-de-l'art dans une bande de fonctionnement entre 300 et 360 GHz, et une puissance d'OL comprise entre 2,5 mW et 4 mW.<br />La dernière partie de la thèse est consacrée à l'étude des propriétés diélectriques de plusieurs échantillons de minéraux, roches et sables dans le domaine millimétrique (jusqu'à 170 GHz), dans le cadre scientifique de la cartographie de la surface de Mars par l'instrument MAMBO. Des mesures de la permittivité de ces matériaux par analyse vectorielle, et des mesures radiométriques faites en collaboration avec l'IAP (Institut de Physique Appliquée) de Berne (Suisse) sont présentées. L'objectif est de mettre en avant les différences d'émissivité des roches carbonatées par rapport à des roches riches en silicates.<br />Ce travail de thèse est également préparatoire aux futurs instruments radiométriques embarqués, pour l'observation de la terre aux longueurs d'onde submillimétriques. Dans cette perspective, le développement de récepteurs hétérodynes intégrant dans une même mécanique plusieurs éléments de mélange et de multiplication en fréquence permettra des avancées technologiques dans le domaine de l'imagerie Terahertz.

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No description available.

The clouds of gas and dust that constitute the Interstellar Medium (ISM) within the Milky Way and other galaxies can be studied through the spectral lines of the atoms and molecules. The ISM follows a lifecycle in which each of its phases can be traced through spectral lines in the Terahertz (THz) portion of the electromagnetic spectrum, loosely defined as 0.3 - 3 THz. Using the high spectral resolution afforded by heterodyne instruments, astronomers can potentially disentangle the large-scale structure and kinematics within these clouds. In order to study the ISM over large size scales, large format THz heterodyne arrays are needed. The research presented in this dissertation focuses on the development of two heterodyne array receiver systems for ISM studies, SuperCam and a Super-THz (>3 THz) receiver. SuperCam is a 64-pixel heterodyne imaging array designed for use on ground-based submillimeter telescopes to observe the astrophysically important CO J=3-2 emission line at 345 GHz. The SuperCam focal plane stacks eight, 1x8 mixer subarrays. Each pixel in the array has its own integrated superconductor-insulator-superconductor (SIS) mixer and Low Noise Amplifier (LNA). In spring 2012, SuperCam was installed on the University of Arizona Submillimeter Telescope (SMT) for its first engineering run with 32 active pixels. A second observing run in May 2013 had 52 active pixels. With the outliers removed, the median double sideband receiver temperature was 104 K. The Super-THz receiver is designed to observe the astrophysically important neutral atomic oxygen line at 4.7448 THz. The local oscillator is a third-order distributed feedback Quantum Cascade Laser operating in continuous wave mode at 4.741 THz. A quasi-optical hot electron bolometer is used as the mixer. We record a double sideband receiver noise temperature of 815 K, which is ~7 times the quantum noise limit and an Allan variance time of 15 seconds at an effective noise fluctuation bandwidth of 18 MHz. Heterodyne performance is confirmed by measuring a methanol line spectrum. By combining knowledge of large array formats from SuperCam and quasi-optical mixers, initial tests and designs are presented to expand the single pixel 4.7 THz receiver into a quasi-optical 16-pixel array.

The objective of this thesis was to develop novel technologies for measuring the physical characteristics of high-speed pulse trains, for use in performance monitoring applications. This thesis describes the development of three separate techniques that perform measurements in either the time domain, frequency domain or the phase space of the optical signal. The first section investigates phase-sensitive pulse measurement techniques. A high- resolution SHG-FROG apparatus was custom-designed to measure 40GHz RZ pulse trains, from which an operational characterisation of a Mach-Zehnder modulator (MZM) was realised. A numerical model of a nonlinear pulse compressor was developed to compress 40GHz RZ pulses from 8.5ps down to 3.4ps. These pulses were time-division multiplexed to 80GHz, and phase-retrievals of the 80GHz pulse trains were measured. A comparison between the techniques of SHG-FROG and linear spectrogram has been undertaken for 10GHz pulse sources, exposing SHG-FROG's weaknesses at this particular repetition rate. The second section investigates a simple, time-averaged, nonlinear detection technique. Two-photon absorption in a GaAs/InGaAs quantum-well laser diode was used to measure the duty cycle (and by extension, the pulse duration) of a range of pulse sources. This technique was further developed to measure the extinction ratio of NRZ pulse trains. Additionally, the pulse duration of a mode-locked laser source was measured using the nonlinear absorption in a 1-m length of As2Se3 Chalcogenide glass fiber. This demonstrates that the nonlinear properties of this glass may well find application in future instrumentation. The third section investigates the development of an ultra-high resolution swept heterodyne spectrometer. This spectrometer was used to spectrally-distinguish repetitive 8-bit NRZ patterns at 2.5Gbit/s. It was also used to measure the chirp parameter of an X-cut LiNbO3 MZM, revealing a chirp parameter of απ/2 < 0.1 across a modulation band- width of 250-2500MHz. Additionally, the distinctive CW spectrum of a DFB laser diode was measured. Analysis of the measured CW spectrum yielded a linewidth enhancement factor of α≃ 1.8 and also the relative intensity noise of the DFB laser diode.

The objective of this thesis was to develop novel technologies for measuring the physical characteristics of high-speed pulse trains, for use in performance monitoring applications. This thesis describes the development of three separate techniques that perform measurements in either the time domain, frequency domain or the phase space of the optical signal. The first section investigates phase-sensitive pulse measurement techniques. A high- resolution SHG-FROG apparatus was custom-designed to measure 40GHz RZ pulse trains, from which an operational characterisation of a Mach-Zehnder modulator (MZM) was realised. A numerical model of a nonlinear pulse compressor was developed to compress 40GHz RZ pulses from 8.5ps down to 3.4ps. These pulses were time-division multiplexed to 80GHz, and phase-retrievals of the 80GHz pulse trains were measured. A comparison between the techniques of SHG-FROG and linear spectrogram has been undertaken for 10GHz pulse sources, exposing SHG-FROG's weaknesses at this particular repetition rate. The second section investigates a simple, time-averaged, nonlinear detection technique. Two-photon absorption in a GaAs/InGaAs quantum-well laser diode was used to measure the duty cycle (and by extension, the pulse duration) of a range of pulse sources. This technique was further developed to measure the extinction ratio of NRZ pulse trains. Additionally, the pulse duration of a mode-locked laser source was measured using the nonlinear absorption in a 1-m length of As2Se3 Chalcogenide glass fiber. This demonstrates that the nonlinear properties of this glass may well find application in future instrumentation. The third section investigates the development of an ultra-high resolution swept heterodyne spectrometer. This spectrometer was used to spectrally-distinguish repetitive 8-bit NRZ patterns at 2.5Gbit/s. It was also used to measure the chirp parameter of an X-cut LiNbO3 MZM, revealing a chirp parameter of απ/2 < 0.1 across a modulation band- width of 250-2500MHz. Additionally, the distinctive CW spectrum of a DFB laser diode was measured. Analysis of the measured CW spectrum yielded a linewidth enhancement factor of α≃ 1.8 and also the relative intensity noise of the DFB laser diode.

The objective of this thesis was to develop novel technologies for measuring the physical characteristics of high-speed pulse trains, for use in performance monitoring applications. This thesis describes the development of three separate techniques that perform measurements in either the time domain, frequency domain or the phase space of the optical signal. The first section investigates phase-sensitive pulse measurement techniques. A high- resolution SHG-FROG apparatus was custom-designed to measure 40GHz RZ pulse trains, from which an operational characterisation of a Mach-Zehnder modulator (MZM) was realised. A numerical model of a nonlinear pulse compressor was developed to compress 40GHz RZ pulses from 8.5ps down to 3.4ps. These pulses were time-division multiplexed to 80GHz, and phase-retrievals of the 80GHz pulse trains were measured. A comparison between the techniques of SHG-FROG and linear spectrogram has been undertaken for 10GHz pulse sources, exposing SHG-FROG's weaknesses at this particular repetition rate. The second section investigates a simple, time-averaged, nonlinear detection technique. Two-photon absorption in a GaAs/InGaAs quantum-well laser diode was used to measure the duty cycle (and by extension, the pulse duration) of a range of pulse sources. This technique was further developed to measure the extinction ratio of NRZ pulse trains. Additionally, the pulse duration of a mode-locked laser source was measured using the nonlinear absorption in a 1-m length of As2Se3 Chalcogenide glass fiber. This demonstrates that the nonlinear properties of this glass may well find application in future instrumentation. The third section investigates the development of an ultra-high resolution swept heterodyne spectrometer. This spectrometer was used to spectrally-distinguish repetitive 8-bit NRZ patterns at 2.5Gbit/s. It was also used to measure the chirp parameter of an X-cut LiNbO3 MZM, revealing a chirp parameter of απ/2 < 0.1 across a modulation band- width of 250-2500MHz. Additionally, the distinctive CW spectrum of a DFB laser diode was measured. Analysis of the measured CW spectrum yielded a linewidth enhancement factor of α≃ 1.8 and also the relative intensity noise of the DFB laser diode.

The objective of this thesis was to develop novel technologies for measuring the physical characteristics of high-speed pulse trains, for use in performance monitoring applications. This thesis describes the development of three separate techniques that perform measurements in either the time domain, frequency domain or the phase space of the optical signal. The first section investigates phase-sensitive pulse measurement techniques. A high- resolution SHG-FROG apparatus was custom-designed to measure 40GHz RZ pulse trains, from which an operational characterisation of a Mach-Zehnder modulator (MZM) was realised. A numerical model of a nonlinear pulse compressor was developed to compress 40GHz RZ pulses from 8.5ps down to 3.4ps. These pulses were time-division multiplexed to 80GHz, and phase-retrievals of the 80GHz pulse trains were measured. A comparison between the techniques of SHG-FROG and linear spectrogram has been undertaken for 10GHz pulse sources, exposing SHG-FROG's weaknesses at this particular repetition rate. The second section investigates a simple, time-averaged, nonlinear detection technique. Two-photon absorption in a GaAs/InGaAs quantum-well laser diode was used to measure the duty cycle (and by extension, the pulse duration) of a range of pulse sources. This technique was further developed to measure the extinction ratio of NRZ pulse trains. Additionally, the pulse duration of a mode-locked laser source was measured using the nonlinear absorption in a 1-m length of As2Se3 Chalcogenide glass fiber. This demonstrates that the nonlinear properties of this glass may well find application in future instrumentation. The third section investigates the development of an ultra-high resolution swept heterodyne spectrometer. This spectrometer was used to spectrally-distinguish repetitive 8-bit NRZ patterns at 2.5Gbit/s. It was also used to measure the chirp parameter of an X-cut LiNbO3 MZM, revealing a chirp parameter of απ/2 < 0.1 across a modulation band- width of 250-2500MHz. Additionally, the distinctive CW spectrum of a DFB laser diode was measured. Analysis of the measured CW spectrum yielded a linewidth enhancement factor of α≃ 1.8 and also the relative intensity noise of the DFB laser diode.

The objective of this thesis was to develop novel technologies for measuring the physical characteristics of high-speed pulse trains, for use in performance monitoring applications. This thesis describes the development of three separate techniques that perform measurements in either the time domain, frequency domain or the phase space of the optical signal. The first section investigates phase-sensitive pulse measurement techniques. A high- resolution SHG-FROG apparatus was custom-designed to measure 40GHz RZ pulse trains, from which an operational characterisation of a Mach-Zehnder modulator (MZM) was realised. A numerical model of a nonlinear pulse compressor was developed to compress 40GHz RZ pulses from 8.5ps down to 3.4ps. These pulses were time-division multiplexed to 80GHz, and phase-retrievals of the 80GHz pulse trains were measured. A comparison between the techniques of SHG-FROG and linear spectrogram has been undertaken for 10GHz pulse sources, exposing SHG-FROG's weaknesses at this particular repetition rate. The second section investigates a simple, time-averaged, nonlinear detection technique. Two-photon absorption in a GaAs/InGaAs quantum-well laser diode was used to measure the duty cycle (and by extension, the pulse duration) of a range of pulse sources. This technique was further developed to measure the extinction ratio of NRZ pulse trains. Additionally, the pulse duration of a mode-locked laser source was measured using the nonlinear absorption in a 1-m length of As2Se3 Chalcogenide glass fiber. This demonstrates that the nonlinear properties of this glass may well find application in future instrumentation. The third section investigates the development of an ultra-high resolution swept heterodyne spectrometer. This spectrometer was used to spectrally-distinguish repetitive 8-bit NRZ patterns at 2.5Gbit/s. It was also used to measure the chirp parameter of an X-cut LiNbO3 MZM, revealing a chirp parameter of απ/2 < 0.1 across a modulation band- width of 250-2500MHz. Additionally, the distinctive CW spectrum of a DFB laser diode was measured. Analysis of the measured CW spectrum yielded a linewidth enhancement factor of α≃ 1.8 and also the relative intensity noise of the DFB laser diode.