Huawei Technologies Co Ltd. says it has developed an embedded optical time-domain reflectometer (eOTDR) prototype with what the company claims is an industry leading split ratio of up to 1:64. Using emulation tests on live networks, the company has demonstrated that this prototype can accurately locate faults to within 5 m, meaning that eOTDR technology is ready for commercial use on fiber-to-the-home (FTTH) passive optical networks (PONs).
An OTDR uses scattered light in fibers to locate faults. Traditionally, FTTH PON maintenance and troubleshooting is performed through external OTDR equipment. This approach requires new fibers to be connected to the optical distribution network (ODN), and is costly and operationally complex. With the rapid expansion of fiber-to-the-x (FTTx) and the exponential growth of fibers, the need for reduced fiber maintenance costs is increasing all the time.
Huawei says its new eOTDR prototype offers cost-effective fiber maintenance by embedding OTDR functionality into an optical transceiver inside the PON optical line terminal (OLT), which operates at the same wavelength as user data. OTDR-embedded optical modules are the same size as common optical modules and can be easily deployed on FTTx for troubleshooting, Huawei asserts. This approach does not require engineering works such as fiber connection changes or adaptation of optical network terminals (ONTs), nor does it interrupt services during troubleshooting, according to Huawei. This approach improves fiber troubleshooting efficiency and reduces costs, the company adds.
Huawei is the second PON systems vendor to announce an embedded OTDR capability, following Alcatel-Lucent (see “Alcatel-Lucent adds integrated OTDR capabilities to PON offering”). NeoPhotonics has announced that it is selling necessary modules (see “NeoPhotonics offers PON OLT optical transceivers with embedded OTDR functions”), and likely is Alcatel-Lucent’s supplier.
For more information on FTTx/access systems and suppliers, visit the Lightwave Buyer’s Guide.