Optical time domain reflectometer tests remote fibre test systems
Just released by Yokogawa Europe, the AQ7277B is a high-performance optical time-domain reflectometer (OTDR) module for use with remote fibre-test systems (RFTS).
An RFTS is designed to improve the efficiency of operation and maintenance management of optical fibre lines installed at a fibre optic cable termination station by constantly monitoring individual fibres in the cable using OTDR technology for continuous measurements. The system indicates the failure location on an electronic map and notifies maintenance staff via email or telephone.
The AQ7277B speeds up the identification and location of failures (such as increased loss, fibre breaks and water ingress) and facilitates restorative maintenance. It also enables the maintenance centre to test the installed equipment as a remote manual test during cable installation.
The ability to perform automatic testing of multiple fibres at once saves installation, time and costs, says the company.
Telecomms carriers can monitor and maintain fibre networks to avoid penalties specified in service level agreements and QoS commitments, as well as invest in maintaining fibre networks by detecting fibre degradation before failure and reduce mean time to repair.
The hardware of the AQ7277B OTDR module is based on the company’s AQ7280 OTDR, with optical performance including short dead zone (0.6 m typical) and high dynamic range (up to 50dB). Its size is reduced by 60 per cent compared to its predecessor, which improves its integration into the RFTS. Dimensions are 230 x 50 x 140mm, and it weighs approximately 1 kg.
There are two models in the AQ7277B family, both equipped with an Ethernet (10BASE-T/100BASE-TX) interface as standard. The AQ7277B-B01 takes measurements at 1650nm. This wavelength does not affect the communication wavelengths of 1310/1490/1550 nm. It is equipped with a built-in cut-off filter to isolate it from wavelengths lower than 1650nm, and so can perform accurate measurements on live lines (where active communication signals are travelling). The model is also optimised for testing passive optical networks (PON), and can measure through the high-port-count splitters used in modern PON systems.
The AQ7277B-B02 is designed for monitoring long-distance optical fibres, over 200km in real-life environmental conditions and is capable of a 50dB dynamic range. It operates at a wavelength of 1550nm.