International Telemetering Conference Proceedings / October 25-28, 1993 / Riviera Hotel and Convention Center, Las Vegas, Nevada / With the advent of high-speed parallel-to-serial conversion interface standards reaching the 1.6 gigabit per second region, it is now possible to remote entire telemetry tracking systems over long distances without the need to maintain receivers, combiners, computers and antenna control units at the pedestal. In addition, it will soon be possible to digitize the RF signal(s) with high-speed flash-video analog-to-digital converters and transfer the data over these same links. This coupled with the improvements in fiber-optic L.E.D. and laser transmitters/ receivers and the constantly decreasing cost of fiber-optic cable, will allow for the eventual elimination of copper cabling for these interfaces. This will net a cost savings for the end user, provide for easier installations and increase the reliability of the overall system. This paper gives a brief history of the development of high-speed fiber-optic interface links, then expands into current interface standards and their utilization (such as MIL-STD-1553B, fiber data distributed interface (FDDI), HIPPI, etc.). Finally, a glimpse into the future of telemetry systems and the possibilities to soon be realized as major manufacturers of fiber-optic interfaces push well into the gigabit region. Topics include: • Replacement of existing copper cables between controller and pedestal using fiber-optic cable with interfaces that are not software-based intensive (black boxes); • Multiplexing pedestal control and status lines, RF feed commands, scan reference signals, and boresite video camera control; • Connecting and controlling multiple controllers and/or pedestals through one common interface cable; • Operating multiple tracking stations through one remote antenna controller; • Digitized RF telemetry signals sent along with pedestal, feed, video commands and status.

International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada / Due to Cost and Safety considerations the Range Division of the 412th Test Wing is upgrading remote telemetry (TM) antenna sites to be operated and monitored remotely. This is possible, in part, due to the installation of fiber optic cable, and the use of ATM communications protocol. Both of these applications significantly reduce signal latency from the remote control station located at Ridley Mission Control Center (RMCC) and the Antenna site. This paper discusses the challenges associated with controlling these sophisticated systems remotely. We will also describe the decisions and how they were made, the concerns over system performance, and the impact to other systems. This paper also addresses the technologies chosen to support the requirements and overcome the challenges. The benefits of remote range sensors are also discussed. We will provide top-level block diagrams of the system architecture.

International Telemetering Conference Proceedings / November 04-07, 1991 / Riviera Hotel and Convention Center, Las Vegas, Nevada / Various high performance fiber optic networks have been in existence and available now for over 10 years. Virtually all of them, until recently, have been designed around the “better idea” of some single company or engineer, and therefore were or became expensive, proprietary systems, with limited support, and limited or no growth potential. Many benefits were still realized by the users in spite of that; primarily in the areas of increased bandwidth, improved security, and the capability to have data transmission over long distances. However, after 5 years of continued development and refinement, the American National Standards Institute (ANSI) X3T9.5 committee has nearly completed acceptance and final approval of the Fiber Data Distributed Interface (FDDI) specifications. The new FDDI standards have already evidenced a tremendous and eager acceptance by the end user community, and are clearly destined to replace Ethernet as the most prevalent network media. FDDI also offers additional benefits specifically of interest to the telemetry market, and therefore represents an ideal Local Area Network (LAN) technology towards which any TM installation should migrate.

International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada / The Guided Weapons Evaluation Facility (GWEF) at Eglin Air Force Base is the Air Force’s premiere munitions hardware-in-the-loop (HITL) simulation facility. HITL simulation testing is a ground based tool used to evaluate the performance of a weapon system at a fraction of the cost of free flight testing. The weapon system is stimulated in a laboratory setting with the electromagnetic environment and physical motion it would experience in an operational setting. The system’s responses to that environment are measured to provide various measures of performance including target tracking ability and miss distance. Electrical interfaces are required in order to control the weapon’s guidance system and to receive and inject signals from the HITL simulation computer system to the weapon under test. These interfaces are usually developed using external control circuits and copper cabling to the guidance unit. The GWEF had a requirement to develop a missile interface with no external copper wires or antennas to support a unique test configuration. The requirement led to the development of a Fiber Optic Telemetry (FOTM) package which would be contained completely within the missile body cavity. The constraints on the FOTM design were considerable. Lack of a suitable commercial off-the-shelf fiber optic telemetry package led to the eventual in house design and fabrication of the FOTM. This paper describes the requirements, design constraints and results achieved in the FOTM design. Although not classical telemetry it does share similarities with conventional telemetry units used for open air weapons testing including size constraints, data rates and thermal considerations.

The two-photon absorption (TPA) coefficient is measured in indium phosphide (InP) using femtosecond pulses to be 45cm/GW at 1.32μm. Nanosecond pulses are subsequently used to find the free-carrier refractive index cross-section, σ_r, and the free-carrier absorption coefficient, σ_fca. The quantity βσ_r is measured to be -113x10⁻²ºcm⁴/GW at 1.064μm and -84x10⁻²ºcm⁴/GW at 1.534μm. At 1.064μm, with β assumed to be 22cm/GW, the value suggested by theory, σ_r is -5.1x10⁻²ºcm³. Similarly, at 1.534μm, assuming β to be 20cm/GW gives a σ_r value of -4.1x10⁻²ºcm³. Due to refraction affecting the measurements of σ_fca, only an upper limit of 1x10⁻¹⁵cm² can be put on its value. The free-carrier experiments are repeated on two samples of cadmium mercury telluride (CMT) having bandgaps of 0.89eV and 0.82eV. For the first sample, β_σr is measured to be -148x10⁻²ºcm⁴/GW. Assuming β to be 89cm/GW gives a σ_r value of -1.7x10⁻²ºcm³ whilst σ_fca is found to be at most 3x10⁻¹⁵cm². Significant linear absorption occurs in the second sample which generates a large free-carrier population. It is shown that this significantly enhances the nonlinearities. Finally, the results of the work are tested by modelling a nonlinear transmission experiment, and the results found in this work give a closer fit to experimental results than the result of theory. Four-wave mixing (FWM) in a photonic crystal fibre is exploited to create a high output power optical parametric amplifier (OPA). To optimise the OPA conversion efficiency, the fibre length has to be increased to 150m, well beyond the walk-off distance between the pump and signal/idler. In this regime, the Raman process can take over from the FWM process and lead to supercontinuum generation. The OPA exhibits up to 40% conversion efficiency, with the idler (0.9μm) and the signal (1.3μm) having a combined output power of over 1.5W.

La dissertation explore différentes applications des fibres optiques en ingénierie quantique. Deux thématiques sont développées : d'une part l'utilisation des fibres optiques monomodales en silice pour l'implémentation d'algorithmes et de protocoles de communication quantiques et d'autre part l'utilisation de la non-linéarité de ces fibres pour réaliser des sources de paires de photons corrélés. L'étude est à la fois théorique et expérimentale./ The dissertation explores various uses of optical fibers for quantum engineering. Two topics are developed : first the use of single-mode silica fibers for implementing quantum algorithms and communication protocols, second the use of these fibers for generating correlated photon-pairs.

No description available.

In state-of-the-art fiber-optics communication systems the fixed forward error correction (FEC) and constellation size are employed. While it is important to closely approach the Shannon limit by using turbo product codes (TPC) and low-density parity-check (LDPC) codes with soft-decision decoding (SDD) algorithm; rate-adaptive techniques, which enable increased information rates over short links and reliable transmission over long links, are likely to become more important with ever-increasing network traffic demands. In this invited paper, we describe a rate adaptive non-binary LDPC coding technique, and demonstrate its flexibility and good performance exhibiting no error floor at BER down to 10(-15) in entire code rate range, by FPGA-based emulation, making it a viable solution in the next-generation high-speed intelligent aggregation networks.

Forward error correction (FEC) is as one of the key technologies enabling the next-generation high-speed fiber optical communications. In this paper, we propose a rate-adaptive scheme using a class of generalized low-density parity-check (GLDPC) codes with a Hamming code as local code. We show that with the proposed unified GLDPC decoder architecture, a variable net coding gains (NCGs) can be achieved with no error floor at BER down to 10(-15), making it a viable solution in the next-generation high-speed fiber optical communications.

Approved for public release; distribution is unlimited / The need for broadband network access is experiencing rapid growth, but what is currently available is not sufficient. Copper-based technologies cannot address the requirements of today's bandwidth-intensive Internet applications. End-users in the "last mile" demand access speeds equivalent to those supported by fiber optics backbone networks, although, the cost and time associated with its installation are prohibitive factors for bringing fiber to every home and business. This results in the well-known "last mile access problem," which prevents the Internet from reaching its full potential, and has paved the way for the development of many innovative technologies. Driven by demands for more bandwidth, wireless broadband technologies have been proposed. This thesis provides an investigation of two candidates to address the lack of adequate bandwidth in the "last mile," Free Space Optics (FSO), and the IEEE 802.11 Wireless Local Area Networking (WLAN) standard. FSO uses optical signals to deliver information at extremely high data rates, more quickly and cost-effectively than fiber systems. The IEEE 802.11 standard uses radio technology to transfer data. They both use license-free frequency bands for transmission through the atmosphere. They both are quickly deployable, easily scalable, and cheaper than wired solutions, characteristics able to support applications requiring high bandwidth and a high degree of mobility. / Lieutenant Commander, Hellenic Navy