A demultiplexer takes a single data stream and routes it to a selected output channel, a bit like one of those old A-B printer switches we used to physically select which printer we were sending data to. In this episode, we show how to design one.

International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada / The Space and Missile Systems Center at Vandenberg AFB has integrated ID-1 high bit rate helical scan digital recorders into the ground based and mobile telemetry receiving and processing facilities. The systems are used for recording higher bit rates than those available with the current IRIG standard longitudinal wideband and double density instrumentation magnetic tape recorder/reproducers. In addition to the 400 Mbps digital recorders, the systems consist of high-speed multiplexer/ demultiplexers and multi-channel bit synchronizers for recording numerous telemetry data links and sources on a single recorder. This paper describes the system configurations and compares recording capabilities with those of the previous generation instrumentation magnetic tape recorder/reproducers.

Photonic crystals (PCs), consisting of a periodic pattern of variations in the material properties, are one of the platforms proposed as synthetic optical materials to meet the need for optical materials with desired properties. Recently, applications based on dispersive properties of the PCs have been proposed in which PCs are envisioned as optical materials with controllable dispersive properties. Unlike the conventional use of PCs to achieve localization, in these new applications propagation inside the photonic crystal is studied, and their dispersive properties are utilized. Among these applications, the possibility of demultiplexing light using the superprism effect is of particular interest. Possibility of integration and compactness are two main advantages of PC-based wavelength demultiplexers compared to other demultiplexing techniques, for applications including compact spectrometers (for sensing applications), demultiplexers (for communications), and spectral analysis (for information processing systems). I develop the necessary simulation tools to study the dispersive properties of photonic crystals. In particular, I will focus on superprism-based demultiplexing in PCs, and define a phenomenological model to describe different effects in these structures and to study important parameters and trends. A systematic method for the optimization and design of these structures is presented. Implementation of these structures is experimentally demonstrated using the devices fabricated in a planar SOI platform based on designed parameters. In the next step, different approaches to improve the performance of these devices (for better resolution and lower insertion loss) are studied, and extension of the concepts to other material platforms is discussed.

[EN] The present PhD thesis deals on the model, design and experimental demonstration of Arrayed Waveguide Grating (AWG) with advanced features. Firstly, building upon existing AWG formulations, design equations are provided, libraries developed and all this is experimentally validated with devices in Indium Phosphide (InP) and Silicon-on-insulator (SOI) technologies. Next, a model and experimental validation is reported for an Interleave-Chirped Arrayed Waveguide Grating (IC-AWG), which is able to process optical signals as WDM demultiplexer, polarization splitter and phase diversity component all in a single device. This device was fabricated and tested in InP technology. The second innovative AWG demonstrated in this thesis, a Reflective type (R-AWG), whose layout allows for tailoring the pass-band shape and to change the spectral resolution. A demonstration of design and fabrication for this device is provided in SOI technology. The last AWG with innovative concepts is one driven by Surface Acoustic Waves (AWG-SAW), where the spectral channels can be tuned by means of acousto-optic effect. The device was fabricated in Aluminium Gallium Arsenide (AlGaAs) technology, and measurements are provided to validate the concept and design flow. In parallel this thesis has resulted in the development of different AWG layouts for a wide number of (generic) technologies and foundries, coded into design libraries, of use in a de-facto standard software employed for the design of photonic integrated circuits. These design libraries have been licensed to the UPV spin-off company VLC Photonics S.L. / [ES] La presente tesis se ha centrado en el modelado, diseño y demostración experimental del dispositivo Arrayed Waveguide Grating (AWG) con funcionalidades avanzadas. Primero, usando la formulación existente sobre AWGs se aportan ecuaciones y librerías de diseño, y se validan experimentalmente por medio de dispositivos fabricados en tecnologías de Indium Phosphide (InP) y Silicon-on-insulator (SOI). Después, se reporta un modelo y demostración experimental para un Interleave-Chirped Arrayed Waveguide Grating (IC-AWG), el cual es capaz de procesar señales ópticas como demultiplexor WDM, divisor de polarización y componente de diversidad de fase en un único dispositivo. Este dispositivo fue fabricado y probado en tecnología de InP. El segundo AWG innovador demostrado en esta tesis es de tipo Reflectante (R-AWG), cuyo diseño permite modificar la forma espectral del canal y cambiar su resolución espectral, incluyendo una demostración de diseño y fabricación de este dispositivo en tecnología de SOI. El último AWG que incluye conceptos innovadores es uno sintonizable por Acoustic Waves (AWGSAW), donde los canales espectrales pueden ser sintonizados por medio del efecto acusto-óptico. Dicho dispositivo fue fabricado en tecnología de Aluminium Gallium Arsenide (AlGaAs), y se han incluido medidas experimentales para validar el concepto y el flujo de diseño. En paralelo junto con esta tesis se han desarrollado diferentes diseños para el AWG en un amplio número de tecnologías (genéricas) y plataformas de fabricación, implementadas en unas librerías de diseño para uno de los softwares m¿as utilizados para el diseño de circuitos integrados ópticos, siendo actualmente el estándar de facto. Dichas librerías de diseño han sido licenciadas a la compañía VLC Photonics S.L., spin-off de la UPV. / [CAT] La present tesi ha estat centrada en el modelatge, disseny i demostració experimental del dispositiu Arrayed Waveguide Grating (AWG) amb funcionalitats avançades. Primer, usant la formulació existent sobre AWGs s'aporten equacions i llibreries de disseny, i es validen experimentalment per mitjà de dispositius fabricats en tecnologies de Indium Phosphide (InP) i Silicon-on-insulator (SOI). Després, es reporta un model i demostració experimental per a un Interleave-Chirped Arrayed Waveguide Grating (IC-AWG), el qual és capaç de processar senyals òptiques com demultiplexor WDM, divisor de polarització i component de diversitat de fase en un únic dispositiu. Aquest dispositiu va ser fabricat i provat en tecnologia de InP. El segon AWG innovador demostrat en aquesta tesi és de tipus Reflector (R-AWG), amb un disseny que permet modificar la forma espectral del canal i canviar la seua resolució espectral, incloent una demostració de disseny i fabricació d'aquest dispositiu en tecnologia de SOI. L'últim AWG que inclou conceptes innovadors és un sintonitzable per Acoustic Waves (AWG-SAW), on els canals espectrals poden ser sintonitzats per mitjà de l'efecte acusto-òptic. Aquest dispositiu va ser fabricat en tecnologia de Aluminium Gallium Arsenide (AlGaAs), i s'han inclòs mesures experimentals per validar el concepte i el flux de disseny. En paral.lel juntament amb aquesta tesi s'han desenvolupat diferents dissenys per al AWG en un ampli nombre de tecnologies (genèriques) i plataformes de fabricació, implementades en unes llibreries de disseny per a un dels programaris més utilitzats per al disseny de circuits integrats òptics, sent actualment l'estàndard de facto. Aquestes llibreries de disseny han estat llicenciades a la companyia VLC Photonics S.L., spin-off de la UPV. / Gargallo Jaquotot, BA. (2016). Advanced arrayed waveguide gratings: models, design strategies and experimental demonstration [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/74646 / TESIS