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A.4.5 Test, Measurement, and Diagnostic Equipment (TMDE) The use of Test, Measurement, and Diagnostic Equipment OXIDE) with Intelligent Transportation Systems (ITS) Animal installation, acceptance testing, and long term operational maintenance should not deter jurisdictions from deploying private networks. Modem system designs and state-of-the-art hardware allow He use of software diagnostic tools to provide communicators link status and error reporting to Be network manager at a dedicated workstation terminal. Network management software is capable of identifying real-time communications errors, the malfunctioning communications unit, the geographic location, and shelf location of the failed unit. Deployment of Metropolitan Area Network (MAN), broadband communications backbones win network manageable elements, allows Me reduction of ~iDE by performing communications unit and module-level communications error reporting. Modern communications equipment design typically provides front panel indicators in addition to the network management reporting to facilitate Mean-Time-to-Repa~r ~), and vendor equipment service agreements provide replacement and depot-level repair of failed units, Printed Circuit Boards (PCBs), and modules. A minimum compliment of TMDE is therefore required for jurisdictional maintenance operations to provide the installation and test, and the long term maintenance to operate advanced systems within scheduled downtime parameters. Junsdictional maintenance should be involved with system and subsystem testing to the following levels: Functional unit, and Board module. Equipment testing to the component level is not regarded as necessary for jurisdictional maintenance activities when modern system architectures are used. Selection of TMDE should be based on the junsdiction's maintenance activity level of repair. Typically, TMDE used in laboratory/electronic repair shops should provide a level of accuracy or readout resolution of four (4) times greater Man the Unit Under Test (OUT). Laboratory and electronic shop TMDE equipment should be manufactured in accordance with Belicore reliability specifications and be directly traceable to meteorological standards provided by Be National Institute of Standards and Technology (LIST) to ensure quality measurements, testing reliability, and repeatability. TMDE bench standards require periodic calibration services to check the L;\NCHRPPhase2.:p~\ NCHRP 3-51 Phase 2 Fmal Report A4-26

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amount of elTor for each operational function and range of the equipment and to realign/repair equipment which fails to meet operating parametric levels defined by the manufacturer. Product selection should consider environmental conditions under which MADE is to be operated (shop or field equipments, this will ensure quality measurements without errors induced by ambient operating conditions. The following discussions pertain to specific commun~cations-related TILDE common to advanced system deployment. HE required for modern communications system installation and long tenn maintenance pertains to the following major categories: Fiber optic cable, Modem communications over twisted wire pair CrwP), Local area networks, Microwave communications, Direct sequence, digital spread spectrum radio, Synchronous optical network (SONNET, American digital hierarchy (ADH), and Video communications. For each category, a description of a minimum compliment of test equipment is provided. The equipment described should provide adequate system installation and long tenn maintenance support for the application area described, but is not considered to be a comprehensive list to provide testing functionality at all repair echelons. Equipment lists have been provided which support jurisdictional maintenance activity levels in addition to network management and equipment depot repair services. A.4.5.1 Fiber Optic Cables In general, optical fiber cables and optical fiber cable systems are extremely reliable with very little maintenance required. Many systems can and have been used in the field for more Man 20 years win little or no maintenance. System maintenance falls into two categones: L;wCHR~Phase2rprs NCHRP3-51 Phase2FmalReport A4-27

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Basic Cable Maintenance Some key elements for basic system maintenance are as-built system documents, spare connectors, jumpers, and test equipment such as Optical Time Domain Reflectometers (OTDR's) and power meters. In addition, the draftsperson should have the capability for element troubleshooting. Applicable test equipment includes: Optical time domain reflectometer (OTDR), and Optical source and power meter. Emergency Restoration The more urgent category of maintenance is emergency restoration. Fiber optic cables can carry an extremely large number of circuits on each fiber. In the event of a partial or catastrophic outage, it is essential to: I) Achieve rapid temporary restoration; and 2) Transition to a final permanent repair without disturbing any fibers over Han the ones being repaired. Some key elements for emergency restoration are a restoration lcit, test equipment, mechanical splices, as-built system documents, and access to expert consultation via phone. Commercially available kits include spare cable, two splice closures, two tool kits, and aR items required for bypassing a damaged section. In most cases, these restoration kits are field-ready for instant response. Equipment which should be on site include OTDRs, power meters, and two-way communication devices. Finally, housed with Be restoration equipment should be Me as-built documents of the systems. These documents are vital in isolating problems, and should be accurate and readily available for restoration crews. Personnel should be trained on emergency restoration prior to this type of maintenance. Tidal training should include safety, use of cable system-designated splice methods and hardware, proper use of the OTDR to test and document Be system, operation of an optical power meter, handing and installation of fiber optic cables and connectors, knowledge of system documentation, troubleshooting, and restoration mesons. Personnel should have practiced these skins completely and expeditiously prior to Be advent of an emergency. :\NCHR~Phase2~p~\ NCHRP3-51 Phase2FinalReport A4-28

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Applicable test eaninment includes -~r Op~cal dme domain reflectometer (OTDR), Optical source and power meter, and Two-way communication devices. For emergency restoration or long term cable maintenance, equnpment should include: . Mechanical stripping tool, Fining compound remover, Tissues, Hook blade knife, Sheath npper, Cable cutters, Scissors, Cleaver, Buffer tube shippers (fiber access tools), Closurefs), Mechanucal splices (for temporary restoration) or fusion splicer (for permanent restoration), Isopropyl alcohol, and Safety equipment. Private Modem and [eased Line Service Over Twisted Wire Pairs (TWP) Opera fing al Subrafe Communications Levels Copper u ire communications, provided by Public Switched Telephone Networks (PSTNs) or by dedicated point-to-point private communications link services, are the most commonly used medium of providing field traffic controller connectivity with Traffic Operations Centers (TOCs). The use of copper as a communications medium presents specific deployment considerations and requires awareness of test procedures involved with installation and operational maintenance. Maintenance personnel should understand basic and advanced troubleshooting techniques and should understand cause-and-effect relationships pertinent to Me effects of Electro-magnedc Interference (E~)lRadio Frequency Interference (1~), impulse L:`NCHRPPhase2rp~s NCHRP3-51 Phase2F~nalReport A4-29

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noise, and distortion with respect to the transmitted signal's power, Frequency, and phase characteristics. Knowledge of analog and digital troubleshooting techniques is required. The experienced field technician should be able to accurately monitor and diagnose warplane communications failures with a minimum complement of TMDE. Applicable test equipment includes: Built-in test for Channel Service UnitsIData Service Units (CSU/DSU) including: Loop-back testing, Data Term~nabon Equipment (DTE), DTE with test pattern DTE/LOOP, and test pattern; Portable digital meter with the following built-in functions: . Oscilloscope, volt-ohm-milliammeter (VOM), frequency counter, and power meter (in dBm); Bit Error Rate Tester (BERT) with built-in signal polling, and answer back functions; Modem, compatible with manufacturer and model deployed in field; Handset (2 way communications); Senal communications exerciser/analyzer, providing bit trap and generator functions; and Breakout box with light emitting diodes (LEDs) providing communication pin activation. The serial communications exerciser/analyzer is typically not required for most problems experienced wig TWP communications, but is listed as a requirement for applications where protocol examination may provide indications as to possible link failures. tonal Area Network (LAND Communications Local Area Network ~AN) communications are becoming prevalent in modern system architecture design and deployment. Communications mediums provided for access to shared r:\NCHRP\Phase2.rp`x NCHRP3-51 Phase2FmalReport A4-30

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resources vary wad deployment schemes. LANs are evolving from the predominant market of copper-based infrastructures to both wireless and fiber optic communications. Specifications for LAN communications are defined by standards developed by the Institute of Electncal and Electronics Engineers (EKE) and American National Standards Institute (ANSO committees on networking technologies. Specifications pertaining to the maximum operating distances and number of terminals need to be observed to maintain proper operational performance of the LAN. LANs currently offer network management software which provide, but are not limited to, the following diagnostic capabilities: Monitonng of network traffic for individual network elements, or composite network analysis, , Setting of network alarms - typically implies that some action is performed upon alarm activation such as providing a log of conditions which precipitated He alarm, i.e., network saturation; Setting of workstation options; Enabling/Disabling of logging of maintained information; Generation of reports; and Compilation of run-time statistics such as frame counts, frame size distribution, network utilization, bytes per second, and frames per second. IbIDE associated win copper based LANs includes: Protocol Analyzer; Hand held digital meter wad oscilloscope, VOM, and power meter; and L:W=~h~2~\ NC~3-51 P~e2F~Re~n A4-31

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Time Domain Reflectometer CADRE. TMDE associated with fiber optic communications requires equipment similar to Mat for backbone plant ~nstaRation and maintenance, with the following addidons: Visible light fiber fault finder; and Protocol analyzer. Wireless LAN communications are a relatively new technology. It is recommended Hat wireless communications elements be serviced under a depot repair agreement. The technology deployed is typically direct sequence, digital spread spectrum communications. Most maintenance operations for aR types of LANs do not require the use of protocol analyzers, except In extreme circumstances. These devices may be procured under lease agreements for "short-tenn" maintenance activities. They are typically very costly and deployment should be provided as a single unit for an organization. Analog and Digifal Microwave Communications Microwave communications links typically have very exact testing requirements to provide compliance win Federal Communications Commission (FCC) certification regulations. Microwave installation acceptance and certification testing requires highly specialized diagnostic troubleshooting skins and the operation of sophisticated TMDE. It is recommended Mat contractual agreements be made to support jurisdictions win this process unless the capability already exists within Be jurisdictional maintenance support personnel. Modem systems are providing more built-in communications maintenance functionality Mat includes software diagnostic tools. The system software provides the capability to run preliminary diagnostics, checking system alignment, and proper operation of interconnected system devices. Test equipment required in support of preliminary microwave systems includes: Digital muldmeter; ~;\NCHRP~Phase:.rp ~NCHRP 3-51 Phase 2 Final Report A4-32

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Power meter; and Frequency counter. The following tools are required: SMA wrench; Small (1J4") slotted screwdriver; Small Phillips screwdriver; and Static-free workstation. A more complete list of TMDE for the long term operational maintenance should include: Spectrum analyzer; Test antenna kit (antennae, antenna correction factors, cables, cable adapters, and tripod); Frequency counter, Signal generator; dB meter; BERT; Voltage Standing Wave Reflectometer (VSWR) meter; Signal-to-noise and distortion (STEAD) measuring device; and Dummy loads. Functionality from several of the above listed TMDE have been consolidated to one piece of specialized microwave test equipment, and are available from a variety of manufacturers. Direef Sequence Digifa/ Spread Speefrum Radio Communications Direct sequence spread spectrum radios providing digital packet network communications have been recently introduced to the Intelligent Transportation System ~S) marketplace. The radios provide communications resiliency by establishing alternate communications routing in the event Me primary channel fails. These radios have been constructed so that sensitive electronics are contained in a positive pressurized environmental housing to protect against ambient env~ronrnental conditions associated with traffic control instaNadon sites. Manufacturers L;\NCHRP\Phase2.rph N~3-51 P~2F~Re~n A4-33

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l recommend a depot-level maintenance service agreement be provided to jurisdictional users at the functional unit level. The following TIDE should be considered for initial deployment and Tong term maintenance: BERT; Spectrum analyzer, and Antennae (directional and omnidirectional), cable adapters, cables, antenna correction factors, and tnpod. Synchronous Optical Network (SONET) Synchronous Optical Network (SONET) communications equipment provides communications as described by Bellcore standards for fiber optic and ANSI standards for electrical interfaces. SONET uses Graphical User interface (GUM network management, providing extensive perfo~ance mon~tonng to include network alarm summaries, fault isolation, alarm history logs, provisioning, adm~nisundon, protection switch ac~vadon, configurations, etc. Network management is typically supported via laptop computer or dedicated workstation terminals. Network management allows local and remote fault isolation doom to He module level to provide maintenance personnel web advance ~ndicabon of He spare modules required to perform repairs. The following TMDE is required: Digital multimeter; Optical power meter; Fiber optic test set; Fiber optic attenuator; and Transmission analyzer. American Digifa/ Hierarchy (ADH) DS-O, DS-', and DS-3 Communications The Amencan Digital Hierarchy (ADH), comprised of digital data communications transfer rates at DS-0 (56/64 Kbps), DS-1 (~.544 Mbps), and DS-3 (44.736 Mbps), is defined by Bellcore and ~:WCHRP`Phasc~rpr\ NCHRP 3-51 Phase 2 final Report A4-34

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ANST specifications. Communications testing of these circuit interfaces is similar in nature to some of He subrate copper-based communications. Bit Error Rate Tests (BERT) to detemune He amount of errored communications seconds is still applicable, as well as He use of frequency counters. Special test equipment has evolved capable of testing broadband communications protocols per DS-! and DS-3. The analyzers are typically expensive, but provide a number of functional tests to determine He health of ADH communications links. Maintenance personnel performing tests on such circuits are required to have strong troubleshooting skins which include advanced test equipment operation and knowledge of He operational protocols used. HE used in testing and evaluating ADH circuits includes: BERT; Frequency counter, and Protocol analyzer. E/A 770A Video Communications Testing Video communications networks deployed In modem systems typically can consist of bow analog and digit distribution systems. End-to~nd video communications quality is required to conform with Electronics Industries Association (ELA) specification ElA 250C, medium haul, when measured as fiercest remote source to He point of termination (display). Medium haul, when tested as an isolated component, should conform to ETA 250C short haul specifications. The ELA 170 signal is encoded with color burst information as defined by the National Television Standards Committee (NTSC). Typically, a test pattern generator with multiburst and color bars should be rack mounted at the nearest add/drop location to the source and at He point of termination (TOC for example). A vectorscope or waveform monitor should be used. This signal analysis and generation equipment should be provided with the ability to be remotely operated upon command at the TOC. Perhaps the easiest way to test to satisfy EIA 250C, is Trough the use of an automatic test signal generator. Hand-held test pattern generators are also resell for testing video systems. Video compressors/decompressors (CODECs) are used to optimize bandwidth over digital communications links. Once in digital format, video is typically tested at He electrical output L:\NCHRP\Phase;~.rptY NCHRP3-51 P~2F~Re~n A4-35