SYSTEM FOR THE CERTIFICATION OF A PASSIVE OPTICAL NETWORK AND FOR THE DETECTION OF PROBLEMS AND FAULTS IN THE LAST FIBRE LEGS

摘要

The invention relates to a system for the certification of a passive optical network and for the detection of problems and faults in the last fibre legs, which is suitable for use in passive optical networks which, between the OLT device housed in a telephone central office and the user device of ONT, includes optical dividers or splitters which, in the downward direction, distribute the optical signal to all of the users within a tree-and-branch architecture, and in the upward direction, combine the optical signals from all of the ONTs. The system is based on the incorporation of a group of devices known as an OLT emulator and a remote testing unit which are joined to the corresponding wall socket of the telephone central office and user, such that the remote testing unit is positioned facing an OLT in operation, allowing the certification of the last leg of the optical network and the detection of problems and faults in a PON network in operation.

主权项

1. System for the certification of a passive optical network and for the detection of problems and faults in the last fibre legs, which is suitable for use in passive optical networks which, between the OLT device housed in a telephone central office and the user device of ONT, connected to the corresponding wall socket, and including optical dividers or splitters which, in the downward direction, distribute the optical signal to all of the users within a tree-and-branch architecture, and in the upward direction, combine the optical signals from all of the ONTs, using two supplementary transmission and reception windows with the use of a monofibre plant for the FTTH deployments, characterized in that the system comprises:
a portable and autonomous OLT emulator device connected to the wall socket to access the plant infrastructure; and a remote testing unit (RTU) connected to the subscriber wall socketsuch that the OLT emulator comprises:
an ASIC or FPGA (36) implementing the GPON protocol on at least one electro-optical module (45) connectable to different PON networks with the capacity to measure optical power and flash memory (43) and RAM (44) peripherals; a packet processor (40), connected to the FPGA (36) to generate the service traffic to be tested, and a second microprocessor (42) dedicated to the control of the provision and testing functions; at least one external USB external data port (39) and an Ethernet port (37) to connect to an external PC (38) to update firmware,while the remote testing unit (RTU) comprises:
a GPON chipset or an FPGA (15) with an embedded microprocessor with flash memory (17) and RAM (34) peripherals; an ONT electro-optical module (20), joined to the chipset or FPGA (15), to measure the optical power received; an optical circuit (47) capable of separating reflected light (28) and sending it to an OLT electro-optical module (21) with the capacity to measure power; a first optical filter (22) that communicates with the ONT electro-optical module (20) capable of separating the downward wavelength (25) from the upward wavelength (27); an optical circulator (24) with a first port (P1) connected at the 1310 nm output of the first optical filter (22), as well as with a second port (P2) connected to a second optical filter (23) to recover the monofibre signal along with the descending wavelength (26) coming from the first filter (22); a PIN (31) that can be activated to detect the reflections of the connections emitted in the OLT electro-optical module (21) and which PIN (31) is connected to a digital logic block (16) that communicates with the activation of the burst transmission of the ONT electro-optical module (20); an optical fibre coil (25) connected to an optical connector (32) with an APC-type polish; a USB-type external connector (19) and an Ethernet-type external connector (18) for the connection to an external PC (33); and a Lithium-Polymer battery block (49) that ensures the autonomy and portability of a field system that does not require electricity to operate.