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  • Essay / Otdr (Optical Time Domain Reflectometer)

    Table of ContentsArchitecture of OTDROWorking of OTDRTypes of OTDRFunctions of an OTDROWorking of an OTDRApplication of OTDROTDR stands for Optical Time Domain Reflectometer. An OTDR needs light scattered through the fibers to locate faults. Traditionally, maintenance and troubleshooting of FTTH PON is performed via external OTDR equipment. This approach requires connecting new fibers to the optical distribution network. This shows that the OTDR is recording the light reflected from the fiber and testing over time. The OTDR operates on one end and produces a “photo” of the cable. The bonded fiber is known as a launch cable. We can operate with a single launch cable and get information with the receive cable. Say no to plagiarism. Get a tailor-made essay on “Why violent video games should not be banned”?Get an original essayThe Architecture of OTDOTDR is the most important examination tool for optical fibers, which is applicable for measuring fiber loss, connector loss and for determining the exact location and value of cable discontinuities. By means of very short pulses, it is also possible to measure the modal dispersion of multimodal fibers. The structure of typical OTDR equipment is shown below: Working of OTDR The principle of OTDR analyzer is that a short light pulse is transmitted in the fiber under test and the incidence time and amplitude reflected pulses are measured. The commonly used pulse width is from nanosecs to microsecs, the pulse power can exceed 10mW. The repetition frequency depends on the length of the fiber, it is generally between 1 and 20 kHz, it is naturally smaller for longer fibers. Dividing by 2 at the oscilloscope inputs is necessary since the vertical (loss) and horizontal (length) scales correspond to the unidirectional length. Types of OTDR There are currently three forms of OTDR on the market. 1-Laboratory OTDR: Laboratory OTDRs are generally used in testing laboratories. They have a particularly long range with many options.2-Mini OTDR: Mini OTDRs are portable and designed for fluid testing.3-Computer-based OTDR: PC connects to a personal computer and operates with software based on Windows.OTDRFast Self-Test Functions: The self-test function provides quick results without knowing much information about the equipment. Connect the fiber first, then press the "Test" button, it will automatically set an optimal test and display accurate test results, such as test curves and event lists. Quick curve analysis: It can find the failure point in the test curve and also find the location information. in the same curve test. Maintain an event list of all events that occurred during testing. Powerful document management: It provides the function of store view, delete and save using PCL language based software. Practical VFL function: With this function we can easily find the disconnection points in short distance optical fiber links. Manual test mode: There are two modes, real time or average time. Rapid testing in real-time mode compared to dynamic testing. Average test mode: Average test mode is used to maximally tolerate noise in the test curves, so as to obtain more accurate test results. The operation of an OTDROTDR uses Rayleigh and Fresnel scattering reflections on the fiber characteristics of the portions. There.