CN112636839A - EPON repeater device for establishing double-ring self-healing network - Google Patents

Abstract

The invention relates to an EPON repeater device for establishing a double-ring self-healing network, which solves the problems in the prior art and has the technical scheme that the EPON repeater device comprises an OEO signal amplification shaper for amplifying and shaping two paths of uplink and downlink signals and an uplink inter-frame reset signal processing chip, wherein each OEO signal amplification shaper comprises an OLT interface, an OLT side light module, an ONU side light module and an ONU interface which are sequentially connected; the ONU side optical module generates an additional light receiving indication signal among the optical burst pulses, the light receiving indication signal is led to the uplink interframe reset signal processing chip, and after being processed by the uplink interframe reset signal processing chip, a signal which accords with the uplink interframe reset is generated and used for resetting the limiting amplifier in the ONU side optical module, so that the limiting amplifier is adjusted to be suitable for the signal intensity working state of the next optical pulse.

Description

EPON repeater device for establishing double-ring self-healing network

Technical Field

The invention belongs to an EPON repeater device, and relates to an EPON repeater device for establishing a double-ring self-healing network.

Background

An EPON repeater is a device for amplifying and shaping an EPON signal in an OEO mode; the OEO is an optical-electrical light, an input optical signal is converted into an electrical signal, amplified and shaped, and then converted into an enhanced optical signal to be output; the EPON adopts a single-fiber bidirectional working mode, two wave band WDM of 1490 nm and 1310 nm are integrated inside the EPON, and optical signals in the downlink direction and the uplink direction can be coupled to the same optical fiber, so that the optical fiber and an optical splitter are saved; in an EPON repeater, uplink and downlink optical signals need to be separated, amplified and shaped respectively, and then the optical signals in the downlink direction and the uplink direction are coupled to the same optical fiber through WDM wave combination; EPONs have been widely used in the field of industrial control, and are a preferred communication technology, especially in the smart grid networking application of national grids, which has a high requirement on communication reliability, and generally adopts a dual-ring self-healing network structure, in this network, a large number of splitters are used, and the splitters distribute optical power unevenly, so that optical power is lost rapidly, and the number of ONUs to which a loop can be connected is reduced, generally 6 to 8, and the communication distance is also short, and is inconvenient to use within 20 km; the device can be used for shaping and amplifying EPON optical signals in the middle position of a ring network, greatly enhances optical power, extends communication distance, overcomes the limitations of communication distance and optical power, improves construction convenience, and can save the number of PON ports occupied by optical fibers and OLT.

Disclosure of Invention

The invention solves the problems that in the prior art, a large number of movable optical connectors and flanges are used, so that the optical power loss is fast, the number of ONU (optical network units) which can be accessed by a loop is reduced, generally 6 to 8 ONU, the communication distance is short, and the use is inconvenient within 20 kilometers, and provides an EPON repeater device for establishing a double-loop self-healing network.

The technical scheme adopted by the invention for solving the technical problems is as follows: an EPON repeater device for establishing a double-ring self-healing network comprises a processing circuit, a power supply, a protection circuit, an indicator light and a network management interface, and is characterized in that: the OEO signal amplification and shaping device comprises an OEO signal amplification and shaping device and an uplink interframe reset signal processing chip, wherein two paths of uplink and downlink signals are subjected to amplification and shaping, and each path of OEO signal amplification and shaping device comprises an OLT interface, an OLT side light module, an ONU side light module and an ONU interface which are sequentially connected; in the downlink direction, the OLT side optical module receives downlink light from the OLT interface, performs amplification and shaping to obtain a PECL differential signal, sends the PECL differential signal to the ONU side optical module, receives the downlink differential PECL signal, is enhanced by the drive of the driver, drives the laser to emit light, enhances the output optical signal, and sends the enhanced optical signal to the ONU connected with the repeater through the ONU interface; in the uplink direction, the ONU side optical module receives uplink laser from the ONU through the ONU interface for amplification and shaping, amplifies an uplink laser signal to a PECL level and sends the level to the OLT side optical module, and the OLT side optical module is driven by a driver to enhance and drive an uplink laser to emit light so that the uplink light is enhanced and sent to an OLT connected with the repeater through the OLT interface; the ONU side optical module generates an additional light receiving indication signal among the optical burst pulses, the light receiving indication signal is led to the uplink interframe reset signal processing chip, and after being processed by the uplink interframe reset signal processing chip, a signal which accords with the uplink interframe reset is generated and used for resetting the limiting amplifier in the ONU side optical module, so that the limiting amplifier is adjusted to be suitable for the signal intensity working state of the next optical pulse. The optical network unit internally comprises two OEO amplifying and shaping circuits, can amplify and shape downlink and uplink optical signals of two EPON signals at the same time, enhances the power of the optical signals, prolongs the communication distance and improves the number of the ONU which can be accessed by a loop.

Preferably, the downlink light-emitting power of the EPON repeater device for establishing the double-ring self-healing network reaches +6dBm, and the light-emitting power of the OLT side light module reaches +1 dBm.

Preferably, the downstream OLT side optical module receives a weak optical signal greater than-28 dBm, and the upstream ONU side optical module receives a weak optical signal greater than-31 dBm.

Preferably, the processing circuit is an ARM CPU circuit, and the ARM CPU circuit reads and transmits a temperature value, a bias current value, a transmitting optical power value and a receiving optical power value of the optical module through I2C buses of the four optical modules. In order to improve the network management and maintainability of the repeater, the repeater of the invention provides the network management function, the ARM CPU and the network management program provide the network management function, and the temperature value, the bias current value, the transmitting luminous power and the receiving luminous power value of the optical module are read out through the I2C buses of the four optical modules and are sent to the WEB interface and the SNMP program module.

Preferably, the uplink interframe reset signal processing chip is a programmable chip FPGA. The programmable chip FPGA has the characteristics of small volume, high integration level and network management maintainability.

The double-ring self-healing network built by the EPON repeater device for building the double-ring self-healing network comprises a double-PON port ONU with a C-type or D-type protection function, when the EPON repeater device for building the double-ring self-healing network cannot receive downlink optical signals from an OLT, the optical signals output to the ONU direction are controlled to be closed, the double-PON port ONU connected with the EPON repeater device for building the double-ring self-healing network switches by judging whether optical signals exist at two PON ports, if one PON port signal is lost, the ONU switches the service to the other PON port, and if the optical signals of the two PON ports are normal, one of the PON ports is selected as a main optical port, and the other PON port is selected as a standby optical port.

The substantial effects of the invention are as follows: the optical network unit internally comprises two OEO amplifying and shaping circuits, can amplify and shape downlink and uplink optical signals of two EPON signals at the same time, enhances the power of the optical signals, prolongs the communication distance and improves the number of the ONU which can be accessed by a loop.

Drawings

FIG. 1 is a block diagram of the internal components of the repeater device of the present invention;

FIG. 2 is a schematic diagram of the first OEO path;

fig. 3 is a schematic diagram of ONU switching of a TYPE C dual PON port single MAC;

fig. 4 is a schematic diagram of ONU switching of dual-PON port and dual-MAC of TYPE D.

Detailed Description

The technical solution of the present invention will be further specifically described below by way of specific examples.

Example 1:

an EPON repeater device for building a double-ring self-healing network, referring to the attached figure 1, comprises a processing circuit, a power supply and protection circuit, an indicator light and a network management interface, wherein an ARM CPU is the processing circuit, and comprises two paths of OEO signal amplification shapers for amplifying and shaping uplink and downlink signals and an uplink interframe reset signal processing chip, wherein each path of OEO signal amplification shapers comprises an OLT interface, an OLT side light module, an ONU side light module and an ONU interface which are connected in sequence; the OLT interface refers TO an optical fiber interface TO OLT A connected with the OLT direction or an optical fiber interface TO OLT B connected with the OLT direction in the graph according TO different connections, the OLT side optical module refers TO a (first path) OPEN OEO OLT side optical module or a (second path) OPEN OEO OLT side optical module in the graph according TO different connections, the ONU side optical module refers TO a (first path) OPEN OEO ONU side optical module or a (second path) OPEN OEO ONU side optical module in the graph according TO different connections, and the ONU interface refers TO an optical fiber interface TO ONU A connected with the ONU direction or an optical fiber interface TO ONU B connected with the ONU direction in the graph according TO different connections. In the downlink direction, the OLT side optical module receives downlink light from the OLT interface, performs amplification and shaping to obtain a PECL differential signal, sends the PECL differential signal to the ONU side optical module, receives the downlink differential PECL signal, is enhanced by the drive of the driver, drives the laser to emit light, enhances the output optical signal, and sends the enhanced optical signal to the ONU connected with the repeater through the ONU interface; in the uplink direction, the ONU side optical module receives uplink laser from the ONU through the ONU interface for amplification and shaping, amplifies an uplink laser signal to a PECL level and sends the level to the OLT side optical module, and the OLT side optical module is driven by a driver to enhance and drive an uplink laser to emit light so that the uplink light is enhanced and sent to an OLT connected with the repeater through the OLT interface; the ONU side optical module generates an additional light receiving indication signal among the optical burst pulses, the light receiving indication signal is led to the uplink interframe reset signal processing chip, and after being processed by the uplink interframe reset signal processing chip, a signal which accords with the uplink interframe reset is generated and used for resetting the limiting amplifier in the ONU side optical module, so that the limiting amplifier is adjusted to be suitable for the signal intensity working state of the next optical pulse. The downlink luminous power of the EPON repeater device for establishing the double-ring self-healing network reaches +6dBm, and the luminous power of the OLT side light module reaches +1 dBm. And the OLT side optical module in the downlink direction receives weak optical signals larger than-28 dBm, and the ONU side optical module in the uplink direction receives weak optical signals larger than-31 dBm. The processing circuit is an ARM CPU circuit, and the ARM CPU circuit reads out the temperature value, the bias current value, the transmitting optical power and the receiving optical power value of the optical module through I2C buses of the four optical modules and transmits the values. The uplink interframe reset signal processing chip is a programmable chip FPGA. The double-ring self-healing network built by the EPON repeater device for building the double-ring self-healing network comprises a double-PON port ONU with a C-type or D-type protection function, when the EPON repeater device for building the double-ring self-healing network cannot receive downlink optical signals from an OLT, the optical signals output to the ONU direction are controlled to be closed, the double-PON port ONU connected with the EPON repeater device for building the double-ring self-healing network switches by judging whether optical signals exist at two PON ports, if one PON port signal is lost, the ONU switches the service to the other PON port, and if the optical signals of the two PON ports are normal, one of the PON ports is selected as a main optical port, and the other PON port is selected as a standby optical port.

More specifically: as shown in fig. 2, a first route of OEO is used to explain the structural principle, in the downlink direction, downlink laser emitted from an OLT is connected to an "OLT side optical module" of an EPON repeater through an optical fiber, a BOSA device inside the OLT side optical module contains a WDM element, and separates the downlink light to emit the downlink light to the PIN device, the PIN device converts the laser into current, and then the current is pre-amplified by a transimpedance amplifier and further amplified by a limiting amplifier to convert the current into a high-speed differential PECL signal, which is output to an ONU side optical module, the ONU side optical module receives the downlink differential signal and then is connected to a downlink laser driver to enhance the emission power, drives the laser to emit light, and the laser is emitted to an ONU connected to the repeater through the optical fiber connected to an optical interface "optical network in the ONU direction of the ONU; in an EPON system, downlink light is continuous light, and the required functions can be realized by adopting a general optical communication technology; in the uplink direction, a burst optical signal sent by the ONU passes through an optical interface-TO ONU in the ONU direction and is coupled into an APD device of an optical module at the ONU side TO be converted into an electric signal; the APD is an avalanche diode, the sensitivity of the avalanche diode is far higher than that of a PIN, the avalanche diode needs higher working voltage, the ONU side light module provides high voltage needed by the APD through an internal booster circuit, the APD can realize multiplication and amplification of photocurrent, and even if a weak light signal smaller than-31 dBm is received, the APD can amplify the current to be large enough to recover a signal with high signal-to-noise ratio. The electrical signal output by the avalanche diode is amplified by the preamplifier and then is amplified by the limiting amplifier to become a high-speed differential PECL signal, such as an uplink high-speed differential signal shown in fig. 2, which is led to an OLT side optical module; in the OLT side optical module, an uplink high-speed differential signal is driven and amplified by a laser driver TO drive an uplink laser TO emit light, and then the uplink high-speed differential signal is combined with downlink laser emitted by the OLT through WDM and is emitted TO OLT equipment through an OLT direction optical interface-TO OLT; the ONU side optical module receives the uplink burst light from the ONU, the working mode is burst receiving and burst amplifying, which is different from a general continuous optical mode, the burst optical signals from each ONU are different in optical fiber path, some optical pulses are strong and some optical pulses are weak, the optical module needs to adjust the amplification factor in a very short time, improve the amplification factor for the weak light and reduce the amplification factor for the strong light so as to ensure that the final output signal amplitude is equal, the ONU side optical module needs to provide an uplink inter-frame reset signal between the optical burst pulses, reset the limiting amplifier and adjust the working state so as to adapt to the intensity of the next optical pulse signal; therefore, the ONU side optical module is specially designed to generate an additional light receiving indication signal which is led to the FPGA and processed by the FPGA to generate an uplink interframe reset signal meeting the requirement of the ONU side optical module. The optical module at the side of the ONU can turn on the downlink laser emission function when receiving the optical signal from the OLT, and the downlink signal from the OLT is amplified and then emitted to the ONU connected behind the repeater; if the optical fiber connected with the optical interface in the OLT direction is broken, the repeater cannot receive downlink laser, the EPON repeater must shut off laser emission towards the ONU direction, the dim light of the laser must be shut off at the same time, and the ONU cannot receive the downlink laser, the switching function is triggered, the service connection of the PON MAC connected with the optical fiber is disconnected, and the service connection of the PON MAC connected with the other optical fiber is started. The downlink light-emitting control signal is a key signal for triggering network protection switching, and when light emitted from the OLT cannot be received, the light-emitting towards the ONU is turned off. The repeater device of the invention needs to cooperate with a double-PON port ONU with C-type or D-type protection function to establish a double-ring self-healing network, when the repeater can not receive downlink optical signals from an OLT, the optical signals output to the ONU direction can be controlled to be closed, the double-PON port ONU connected with the repeater switches by judging whether optical signals exist in two PON ports, if one PON port signal is lost, the ONU switches the service to the other PON port, and if the optical signals of the two PON ports are normal, the ONU selects one PON port as a main optical port and the other PON port as a standby optical port; as shown in fig. 3, it is illustrated that a TYPE C ONU switches, where there are two PON ports inside the TYPE C ONU, but there is only one PON MAC, and such ONU switches by switching a PON port connected to the PON MAC, and after a switching action occurs, the PON MAC needs to re-register to another different PON port of the OLT, so that extra registration time is needed, and thus the switching time of such ONU is slow; as shown in fig. 4, it is a switching indication of a TYPE D ONU, where the TYPE D ONU has two PON ports inside, and the two PON MACs work simultaneously, and register online on different PON ports of the OLT at the same time, and the ONU is switched at a service port of the ONU, and does not need to re-initiate registration with the OLT during switching, and the switching speed is fast; the method is characterized in that an EPON network with a double-ring protection function is constructed, an OLT with at least two PON ports is needed, the point is easy to meet, the OLT in the market basically has more than two PON ports, a large OLT has hundreds of PON ports, only a double-ring self-healing network of a minimum system is constructed here as an example, a PON port A of the OLT is connected with an outer ring optical fiber in the anticlockwise direction, the outer ring optical fiber is firstly connected with a one-to-two optical splitter 1, the optical splitter generally adopts a splitting ratio of 20% to 80%, wherein 80% of the optical splitter is connected with a next-stage trunk optical fiber, and 20% of the optical splitter is connected with a PON MAC 1 of a local ONU 1; the optical splitter 2 is characterized in that 20% of branch optical fibers of the optical splitter 2 are connected with PON MAC2 of the ONU1, the ONU for constructing the double-ring self-healing network is required to be TYPE C or TYPE D TYPE ONU, the TYPE D TYPE ONU is most ideal, the PON ONU1 corresponds to a first group of PON MAC, the PON ONU 2 corresponds to a second group of PON MAC, the TYPE D TYPE ONU and the two PON MACs work simultaneously, the external equipment is connected with one of the two groups of PON MACs through a change-over switch, the change-over switch can adopt a high-speed MOS analog switch chip, a 1+1 protection mode is adopted, the change-over speed is very high, and as long as one group of PON MACs works normally, the service of the external equipment cannot be interrupted.

The EPON repeater device provided by the invention has two OEOs, can simultaneously amplify two EPON optical signals, and can prolong the perimeter of the whole loop by one time or increase the number of ONU connected with the loop by one time only by adding the EPON repeater to the middle position of the loop; the TO OLT A port and the TO ONU A port of the repeater correspond TO the first path of OEO; the TO OLT port B and the TO ONU port B correspond TO a second path of OEO, the TO OLT A is connected with optical fibers of an inner ring along the clock direction and finally connected TO the PON port B of the OLT through the inner ring optical fibers, downlink 1490 nanometer laser emitted by the PON port B of the OLT in the downlink direction reaches the TO OLT port A of the repeater through a plurality of inner ring optical splitters and the optical fibers, and is emitted TO the PON ports 2 of the ONU1 and the ONU 2 connected behind the repeater through the TO ONU A after being regenerated and amplified by the repeater; in the direction of an outer ring, a TO OLT B port of another group of OEOs of the repeater is connected with a PON port A of the OLT through an optical splitter 3 and an optical splitter 1; in the downlink direction, a downlink 1490 nm laser emitted from the PON port A of the OLT is sent TO a TO OLT port B of the repeater through 80% branches of the optical splitter 1 and the optical splitter 3 of the outer ring, is subjected TO regeneration amplification, is sent TO 20% branches of the optical splitter 6 and the optical splitter 8 through a TO ONU port B, and is sent TO the MAC PON 1 of the ONU 3 and the ONU 4; the transmission direction of the uplink light is opposite to that of the downlink light, and the wavelength of the EPON uplink light is 1310 nanometers. According TO the principle of loop switching, if two optical fibers of a loop are disconnected, an ONU1 and an ONU 2 are connected with a PON port A of an OLT through an optical splitter 1 and an optical splitter 3, and because the optical splitter 2 and an optical splitter 4 are disconnected with TO ONU A ports of two EPON repeaters, optical signals connected with a PON MAC2 port of the ONU1 are lost, optical signals connected with a PON MAC2 of the ONU 2 are also lost, and the ONU1 and the ONU 2 sense that the two optical signals are lost, so that services are switched TO the PON MAC 1; similarly, the PON ports 2 of the ONUs 3 and 4 are normally connected TO the PON port B of the OLT, the TO OLT B of the two EPONs cannot receive the optical signal from the OLT a port due TO the broken optical fiber, the two EPON repeaters can control TO cut off the optical signal of the TO ONU B port, so that the optical splitters 6 and 8 of the outer ring do not have the optical signal, the PON MAC 1 optical signals of the ONUs 3 and 4 are lost, and the ONUs 3 and 4 can start the switching control function TO switch the service TO the PON MAC 2.

The above-described embodiments are only preferred embodiments of the present invention, and are not intended to limit the present invention in any way, and other variations and modifications may be made without departing from the spirit of the invention as set forth in the claims.

Claims (6)

1. An EPON repeater device for establishing a double-ring self-healing network comprises a processing circuit, a power supply, a protection circuit, an indicator light and a network management interface, and is characterized in that: the OEO signal amplification and shaping device comprises an OEO signal amplification and shaping device and an uplink interframe reset signal processing chip, wherein two paths of uplink and downlink signals are subjected to amplification and shaping, and each path of OEO signal amplification and shaping device comprises an OLT interface, an OLT side light module, an ONU side light module and an ONU interface which are sequentially connected; in the downlink direction, the OLT side optical module receives downlink light from the OLT interface, performs amplification and shaping to obtain a PECL differential signal, sends the PECL differential signal to the ONU side optical module, receives the downlink differential PECL signal, is enhanced by the drive of the driver, drives the laser to emit light, enhances the output optical signal, and sends the enhanced optical signal to the ONU connected with the repeater through the ONU interface; in the uplink direction, the ONU side optical module receives uplink laser from the ONU through the ONU interface for amplification and shaping, amplifies an uplink laser signal to a PECL level and sends the level to the OLT side optical module, and the OLT side optical module is driven by a driver to enhance and drive an uplink laser to emit light so that the uplink light is enhanced and sent to an OLT connected with the repeater through the OLT interface; the ONU side optical module generates an additional light receiving indication signal among the optical burst pulses, the light receiving indication signal is led to the uplink interframe reset signal processing chip, and after being processed by the uplink interframe reset signal processing chip, a signal which accords with the uplink interframe reset is generated and used for resetting the limiting amplifier in the ONU side optical module, so that the limiting amplifier is adjusted to be suitable for the signal intensity working state of the next optical pulse.

2. An EPON repeater apparatus for assembling a dual-ring self-healing network according to claim 1, wherein: the downlink luminous power of the EPON repeater device for establishing the double-ring self-healing network reaches +6dBm, and the luminous power of the OLT side light module reaches +1 dBm.

3. An EPON repeater apparatus for assembling a dual-ring self-healing network according to claim 1, wherein: and the OLT side optical module in the downlink direction receives weak optical signals larger than-28 dBm, and the ONU side optical module in the uplink direction receives weak optical signals larger than-31 dBm.

4. An EPON repeater apparatus for assembling a dual-ring self-healing network according to claim 1, wherein: the processing circuit is an ARM CPU circuit, and the ARM CPU circuit reads out the temperature value, the bias current value, the transmitting optical power and the receiving optical power value of the optical module through I2C buses of the four optical modules and transmits the values.

5. An EPON repeater apparatus for assembling a dual-ring self-healing network according to claim 1, wherein: the uplink interframe reset signal processing chip is a programmable chip FPGA.

6. An EPON repeater apparatus for assembling a dual-ring self-healing network according to claim 1, wherein: the double-ring self-healing network built by the EPON repeater device for building the double-ring self-healing network comprises a double-PON port ONU with a C-type or D-type protection function, when the EPON repeater device for building the double-ring self-healing network cannot receive downlink optical signals from an OLT, the optical signals output to the ONU direction are controlled to be closed, the double-PON port ONU connected with the EPON repeater device for building the double-ring self-healing network switches by judging whether optical signals exist at two PON ports, if one PON port signal is lost, the ONU switches the service to the other PON port, and if the optical signals of the two PON ports are normal, one of the PON ports is selected as a main optical port, and the other PON port is selected as a standby optical port.

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