TECHNICAL FIELD

Embodiments of this application relate to the communications field and, in particular, to an optical communications apparatus, an optical line termination, and an optical communication processing method.

BACKGROUND

In a passive optical network (PON) communications system, a plurality of optical network units (ONU) are connected to a single service port of an optical line termination (OLT) by using a feeder optical fiber, an optical splitter, and a distribution optical fiber to form a service channel.

Currently, devices in the PON communications system have evolved from a gigabit-capable passive optical network (GPON) to a 10 gigabit-capable passive optical network (XG-PON) and then to a 10 gigabit-capable symmetric passive optical network (XGS-PON). Because devices in different generations of PON communications systems have different transmission rates, a matching OLT and ONU need to be used for each generation.

A current OLT is used as an example, an optical transmitter and an optical receiver that are of the service port of the OLT are separated and assembled into a single integrated optical transceiver module (hereinafter referred to as an optical module), to facilitate overall maintenance and replacement. Each generation of OLT must match a corresponding optical module. For example, the first generation of GPON OLT matches a GPON OLT optical module that supports a downstream wavelength of 1490 nanometers (nm) and a rate of 2.48832 Gbps (1000 bytes per second, Gbps), and that supports an upstream wavelength of 1310 nm and a rate of 1.24416 Gbps. The second generation of XG-PON OLT matches an XG-PON OLT optical module that supports a downstream wavelength of 1577 nm and a rate of 9.95328 Gbps, and that supports an upstream wavelength of 1270 nm and a rate of 2.48832 Gbps. The third generation of XGS-PON OLT matches an XGS-PON OLT optical module that supports a downstream wavelength of 1577 nm and a rate of 9.95328 Gbps, and that supports an upstream wavelength of 1270 nm and a rate of 9.95328 Gbps.

In the prior art, devices in different generations of PON communications systems have different transmission rates, and a matching OLT, optical module, and ONU need to be used for each generation of PON communications system. Different generations of optical modules have different upstream and downstream rates or different signal level types. Therefore, the different generations of optical modules cannot be used as substitutes. In the prior art, each generation of OLT can adapt only to an optical module and an ONU of a same generation as the OLT. When an operator needs to upgrade an old generation of OLT to a new generation of OLT, the operator also needs to, according to the prior art, upgrade an old generation of optical module to a new generation of optical module, and upgrade an old generation of ONU to a new generation of ONU. Among all optical modules and ONUs connected to the OLT, some users need to upgrade the optical modules and the ONUs while some users do not need to upgrade the optical modules and the ONUs. However, according to the prior art, the OLT, the optical module, and the ONU can only be upgraded at the same time, but different users have different urgency degrees of upgrading the optical modules and the ONUs. Therefore, upgrading all the optical modules and the ONUs causes unnecessary replacement costs of the optical modules and the ONUs, and causes serious resource waste.

SUMMARY

Embodiments of this application provide an optical communications apparatus, an optical line termination, and an optical communication processing method so that a same optical communications apparatus can be compatible with different generations of optical modules. When a user does not need to upgrade an optical module and an ONU, the optical module and the ONU do not need to be upgraded or replaced. This reduces costs.

To resolve the foregoing problem, the embodiments of this application provide the following technical solutions.

According to a first aspect, an embodiment of this application provides an optical communications apparatus. The optical communications apparatus includes a control apparatus and an optical module matching apparatus, where the control apparatus is connected to a control end of the optical module matching apparatus. The control apparatus is configured to output a first control signal to the control end so that the optical module matching apparatus is in a first working mode, where an input end of the optical module matching apparatus is configured to connect to a first optical module, and receive a first electrical signal output by the first optical module, and an output end of the optical module matching apparatus outputs a first serial signal. The control apparatus is further configured to output a second control signal to the control end so that the optical module matching apparatus is in a second working mode, where the input end of the optical module matching apparatus is further configured to connect to a second optical module, and receive a second electrical signal output by the second optical module, and the output end of the optical module matching apparatus outputs a second serial signal. The first electrical signal and the second electrical signal have different level types.

In this embodiment of this application, the optical communications apparatus includes the control apparatus and the optical module matching apparatus. The control apparatus is connected to the control end of the optical module matching apparatus. The control apparatus is configured to output the first control signal to the control end so that the optical module matching apparatus is in the first working mode. The input end of the optical module matching apparatus is configured to connect to the first optical module and receive the first electrical signal output by the first optical module. Then, the output end of the optical module matching apparatus outputs the first serial signal. The control apparatus is further configured to output the second control signal to the control end so that the optical module matching apparatus is in the second working mode. The input end of the optical module matching apparatus is further configured to connect to the second optical module, and receive the second electrical signal output by the second optical module. Then, the output end of the optical module matching apparatus outputs the second serial signal. The first electrical signal and the second electrical signal have different level types. When the input end of the optical communications apparatus provided in this embodiment of this application inputs different electrical signals, the output end of the optical communications apparatus may output different serial signals. Therefore, the optical module matching apparatus in this embodiment of this application may be configured to connect to different optical modules, and a same optical communications apparatus can be compatible with different generations of optical modules. When a user does not need to upgrade an optical module and an ONU, the optical module and the ONU do not need to be upgraded or replaced. This reduces costs. In addition, when the user needs to upgrade the optical module and the ONU, the optical module matching apparatus compatible with the different optical modules is used in the optical communications apparatus, and the entire optical communications apparatus does not need to be upgraded. This reduces costs.

In a possible implementation of the first aspect, the first electrical signal and the second electrical signal have different serial data rates. The first optical module and the second optical module separately output electrical signals at different serial data rates. In an actual application, a serial data rate of an output electrical signal may be determined based on a type of the optical module.

In a possible implementation of the first aspect, the optical communications apparatus further includes at least one of the following modules: the first optical module and the second optical module.

In a possible implementation of the first aspect, the optical communications apparatus further includes a media access control MAC chip. The control apparatus is connected to the MAC chip, the MAC chip supports a first optical communication protocol and a second optical communication protocol, and the output end of the optical module matching apparatus is connected to the MAC chip. When the first serial signal is output to the MAC chip, the MAC chip parses the signal according to the first optical communication protocol. When the second serial signal is output to the MAC chip, the MAC chip parses the signal according to the second optical communication protocol. The output end of the optical module matching apparatus may be connected to the MAC chip. The optical module matching apparatus described herein may be directly connected to the MAC chip or indirectly connected to the MAC chip. For example, the MAC chip has an input end, and the input end of the MAC chip is directly connected to the output end of the optical module matching apparatus. For another example, a serial-to-parallel conversion apparatus is connected between the MAC chip and the optical module matching apparatus. The serial-to-parallel conversion apparatus may be specifically a serdes apparatus. A serial signal output by the optical module matching apparatus is converted into a parallel signal by the serial-to-parallel conversion apparatus, and then the parallel signal may be input to the MAC chip.

In a possible implementation of the first aspect, optical signals respectively generated by using the first optical communication protocol and the second optical communication protocol have different serial data rates.

In a possible implementation of the first aspect, the optical module matching apparatus includes a first resistor, a second resistor, a first switch, a first capacitor, and two transmission lines. The first switch includes the control end. The input end and the output end are separately connected to two ends of the transmission line. The first resistor and the second resistor are connected in series and then bridged between the two transmission lines. An intermediate point between the first resistor and the second resistor that are connected in series is connected to a ground point by using the first capacitor. The first switch is bridged between the intermediate point and the ground point. The first control signal controls the first switch to be opened so that the optical module matching apparatus is in the first working mode, and the second control signal controls the first switch to be closed so that the optical module matching apparatus is in the second working mode. Alternatively, the first control signal controls the first switch to be closed so that the optical module matching apparatus is in the first working mode, and the second control signal controls the first switch to be opened so that the optical module matching apparatus is in the second working mode. The first switch includes the control end. A processor of an OLT board is connected to the control end. The two ends of the transmission line are respectively connected to the input end and the output end of the optical module matching apparatus. The input end of the optical module matching apparatus is connected to an output end of the optical module, and the output end of the optical module matching apparatus is connected to the serial-to-parallel conversion apparatus. The first resistor and the second resistor are connected in series and then bridged between the two transmission lines. The processor of the OLT board may control the first switch to be opened or closed through the control end.

In a possible implementation of the first aspect, the optical module matching apparatus includes a buffer and two transmission lines. The buffer includes the control end. The input end and the output end are separately connected to two ends of the transmission line. An output end of the buffer is connected in series to the two transmission lines in an alternating-current coupling manner. To resolve a prior-art problem that a common-mode voltage of a signal input by the serial-to-parallel conversion apparatus is relatively high, the output end of the buffer is connected in series to the two transmission lines in the alternating-current coupling manner. After outputting a signal, the buffer can be used to connect to a serdes input port in the alternating-current coupling manner to solve the problem that the common-mode voltage is too high after a direct-current coupling of the electrical signal output by the optical module.

In a possible implementation of the first aspect, the buffer includes a third resistor, a fourth resistor, a fifth resistor, a second switch, and a second capacitor. The second switch includes the control end. The third resistor and the fourth resistor are connected in series and then bridged between the two transmission lines. An intermediate point between the third resistor and the fourth resistor that are connected in series is connected to a ground point by using the second capacitor. The fifth resistor and the second switch are connected in series and then bridged between the intermediate point and the ground point. The first control signal controls the second switch to be opened so that the optical module matching apparatus is in the first working mode, and the second control signal controls the second switch to be closed so that the optical module matching apparatus is in the second working mode. Alternatively, the first control signal controls the second switch to be closed so that the optical module matching apparatus is in the first working mode, and the second control signal controls the second switch to be opened so that the optical module matching apparatus is in the second working mode. Therefore, the processor may control, by using the control end, the second switch to be opened or closed. In this embodiment of this application, the buffer includes an input end and the output end that have a level compatibility matching function. Direct-current coupling terminal matching circuits of the LVPECL level and the CML level may be used as output ports of the buffer, and after outputting a signal, the buffer is connected to a serdes input port in an alternating-current coupling manner. The buffer provided in this embodiment of this application can buffer a signal. Because the serdes uses a technology such as 16 nm, a problem that an input common-mode voltage cannot be very wide is caused. The function of the buffer is simple and can be implemented by using a process that has a good tolerance capability for a common-mode level of a signal to isolate damage caused by the common-mode level to a subsequent serdes input port. The buffer provided in this embodiment of this application can resolve the problem that the common-mode voltage is excessively high after a direct-current coupling of the electrical signal output by the optical module.

In a possible implementation of the first aspect, the optical module matching apparatus includes a third switch, a first level matching circuit, and a second level matching circuit. The third switch includes the control end. The first control signal controls the third switch to switch to the first level matching circuit so that the optical module matching apparatus is in the first working mode. The input end and the output end are separately connected to two ends of the first level matching circuit. The second control signal controls the third switch to switch to the second level matching circuit so that the optical module matching apparatus is in the second working mode. The input end and the output end are separately connected to two ends of the second level matching circuit. The first level matching circuit is configured to output the first serial signal, and the second level matching circuit is configured to output the second serial signal.

In this embodiment of this application, the optical module matching apparatus may switch, by using the third switch, a signal output by the optical module to a different level matching circuit so that a device bandwidth performance of the third switch meets a high-frequency switching requirement. When a level type of the signal output by the optical module is the CML level, the first level matching circuit is in the CML alternating-current coupling manner. When the level type of the signal output by the optical module is the LVPECL level, the second level matching circuit is in the LVPECL coupling manner. Different serial-to-parallel conversion apparatuses may be separately connected to a PON MAC module so that the PON MAC module uses different serdes input ports when the optical module outputs signals of different levels.

In a possible implementation of the first aspect, the first level matching circuit includes two transmission lines. The first control signal controls the third switch to switch to the first level matching circuit, and the input end and the output end are separately connected to two ends of the transmission line.

In a possible implementation of the first aspect, the second level matching circuit includes a sixth resistor, a seventh resistor, and two transmission lines. The first control signal controls the third switch to switch to the second level matching circuit. The input end and the output end are separately connected to two ends of the transmission line. An intermediate point between the sixth resistor and the seventh resistor that are connected in series is connected to a ground point.

In a possible implementation of the first aspect, an eighth resistor and a third capacitor are connected in series on the transmission line respectively, where the eighth resistor is configured to attenuate a swing of the first serial signal or a swing of the second serial signal, and the third capacitor is configured to isolate a direct current signal. To reduce signal reflection caused by the optical module matching apparatus, the eighth resistor can be connected in serial to the transmission line to optimize signal reflection close to the output side. In addition, the swing in LVPECL mode may be reduced, to adapt to a swing requirement of the serdes input port. In addition, in this embodiment of this application, the third capacitor is connected in series to the transmission line to isolate the direct current signal so that the alternating-current signal can be transmitted to the serial-to-parallel conversion apparatus.

In a possible implementation of the first aspect, the control apparatus is further configured to: read an optical module identification code from an optical module, output the first control signal when the optical module identification code indicates the first optical module, and output the second control signal when the optical module identification code indicates the second optical module. In this embodiment of this application, each optical module in the optical communications apparatus has a corresponding optical module identifier, where the optical module identifier may be a type identifier of the optical module. For example, the processor is connected to a register of the optical module through an optical module management interface, and the processor reads optical module information through the optical module management interface (for example, an I2C interface) to automatically identify the optical module identifier. If the optical module identification code indicates the first optical module, the processor may output the first control signal, where the first control signal is sent to the optical module matching apparatus by using the control end. If the optical module identification code indicates the second optical module, the processor may output the second control signal, where the second control signal is sent to the optical module matching apparatus by using the control end.

In a possible implementation of the first aspect, the control apparatus is further configured to: receive configuration information input by a management port of the optical communications apparatus, output the first control signal when the configuration information indicates the first optical module, and output the second control signal when the configuration information indicates the second optical module. In this embodiment of this application, an operator of the PON communications system may further deliver the configuration information of the optical module in a manner of a network management system, a command line, or the like based on a type of the optical module actually inserted into the optical communications apparatus so that the processor can automatically identify the optical module identifier. If the configuration information indicates the first optical module, the processor may output the first control signal, where the first control signal is sent to the optical module matching apparatus by using the control end. If the configuration information indicates the second optical module, the processor may output the second control signal, where the second control signal is sent to the optical module matching apparatus by using the control end.

In a possible implementation of the first aspect, a level type of the first electrical signal is a low-voltage positive emitter-coupled logic LVPECL level, and a level type of the second electrical signal is a current mode logic CML level. Alternatively, a level type of the first electrical signal may be a CML level, and a level type of the second electrical signal may be an LVPECL level. The CML level and the LVPECL level have different common-mode levels and swings. Therefore, it may be considered that the CML level and the LVPECL level have different level types. In addition, in this embodiment of this application, the LVPECL level can only be normally output based on an external pull-down resistor, and the CML level can be output not based on the pull-down resistor. In another embodiment, the first electrical signal or the second electrical signal may also be another type of level signal other than the LVPECL level and the CML level. This is not limited herein.

In a possible implementation of the first aspect, the first optical communication protocol and the second optical communication protocol are respectively one of the following plurality of optical communication protocols: a gigabit-capable passive optical network GPON protocol, a 10 gigabit-capable passive optical network XG-PON protocol, 10 gigabit-capable symmetric passive optical network XGS-PON protocol. The first optical communication protocol and the second optical communication protocol are two different protocols.

In a possible implementation of the first aspect, the control apparatus is a processor or a control circuit. In this embodiment of this application, the control apparatus included in the optical communications apparatus may be specifically the processor or the control circuit, provided that different control signals can be output to the control end.

In a possible implementation of the first aspect, the optical communications apparatus is a single board or a printed circuit board PCB. The single board may also be referred to as a board or a line card. For example, in subsequent embodiments, the optical communications apparatus may be referred to as an OLT board or an OLT line card for short. In an actual application, a specific shape of the optical communications apparatus may be set based on a specific scenario of the optical communications apparatus. This is not limited herein.

According to a second aspect, an embodiment of this application provides an optical line termination OLT. The OLT includes the optical communications apparatus according to any one of the first aspect or the possible implementations of the first aspect.

In the second aspect of this application, composition modules of the OLT may be alternatively the architecture described in the first aspect and the possible implementations. For details, refer to the descriptions in the first aspect and the possible implementations.

According to a third aspect, an embodiment of this application provides an optical communication processing method. The method includes. When an optical module matching apparatus receives a first control signal output by a control apparatus, the optical module matching apparatus enters a first working mode, the optical module matching apparatus receives a first electrical signal output by a first optical module, and the optical module matching apparatus outputs a first serial signal; or when the optical module matching apparatus receives a second control signal output by the control apparatus, the optical module matching apparatus enters a second working mode, the optical module matching apparatus receives a second electrical signal output by a second optical module, and the optical module matching apparatus outputs a second serial signal. The first electrical signal and the second electrical signal have different level types.

In the embodiment provided in the third aspect of this application, the control apparatus outputs the first control signal to the control end so that the optical module matching apparatus is in the first working mode. The optical module matching apparatus receives the first electrical signal output by the first optical module, and the optical module matching apparatus outputs the first serial signal. The control apparatus outputs the second control signal to the control end so that the optical module matching apparatus is in the second working mode. The optical module matching apparatus receives the second electrical signal output by the second optical module, and the optical module matching apparatus outputs the second serial signal. When the optical module matching apparatus provided in this embodiment of this application inputs different electrical signals, the optical module matching apparatus may output different serial signals. Therefore, the optical module matching apparatus in this embodiment of this application may be configured to connect to different optical modules so that a same optical module matching apparatus can be compatible with different generations of optical modules. When a user does not need to upgrade an optical module or an ONU, the user does not need to upgrade or replace the optical module or the ONU. This reduces costs. In addition, when the user needs to upgrade the optical module and the ONU, the optical module matching apparatus compatible with the different optical modules is used in the optical communications apparatus, and the entire optical communications apparatus does not need to be upgraded. This reduces costs.

In a possible implementation of the third aspect, the optical module matching apparatus is plugged with an optical module; and the method further includes: The control apparatus reads an optical module identification code from the optical module; and when the optical module identification code indicates the first optical module, the control apparatus outputs the first control signal; or when the optical module identification code indicates the second optical module, the control apparatus outputs the second control signal. In this embodiment of this application, each optical module has a corresponding optical module identification code, and the optical module identification code may be a type identifier of the optical module. For example, the control apparatus is connected to a register of the optical module through an optical module management interface, and the control apparatus reads optical module information through the optical module management interface (for example, an I2C interface), to automatically identify the optical module identifier. If the optical module identification code indicates the first optical module, the control apparatus may output the first control signal, and the first control signal is sent to the optical module matching apparatus by using the control end. If the optical module identification code indicates the second optical module, the control apparatus may output the second control signal, and the second control signal is sent to the optical module matching apparatus by using the control end.

In a possible implementation of the third aspect, the optical module matching apparatus is plugged with an optical module: and the method further includes: The control apparatus reads an optical module identification code from the optical module; when the optical module identification code indicates the first optical module, the control apparatus outputs the first control signal; and when the optical module identification code indicates the second optical module, the control apparatus outputs the second control signal. In this embodiment of this application, an operator of the PON communications system may further deliver the configuration information of the optical module in a manner of a network management system, a command line, or the like based on a type of the optical module actually inserted into the optical communications apparatus so that the control apparatus can automatically identify the optical module identifier. If the configuration information indicates the first optical module, the control apparatus may output the first control signal, where the first control signal is sent to the optical module matching apparatus by using the control end. If the configuration information indicates the second optical module, the control apparatus may output the second control signal, where the second control signal is sent to the optical module matching apparatus by using the control end.

According to a fourth aspect, an embodiment of this application provides a computer-readable storage medium. The computer-readable storage medium stores an instruction. When the instruction is run on a computer, the computer is enabled to perform the method according to the third aspect.

According to a fifth aspect, an embodiment of this application provides a computer program product including an instruction. When the computer program product runs on a computer, the computer is enabled to perform the method according to the third aspect.

According to a sixth aspect, an embodiment of this application provides an optical communications apparatus. The optical communications apparatus may include an entity such as an optical line termination or a chip, and the optical communications apparatus includes a control apparatus and a memory. The memory is configured to store an instruction, and the control apparatus is configured to execute the instruction in the memory so that the communications apparatus performs the method according to any one of the first aspect or the second aspect.

According to a seventh aspect, this application provides a chip system. The chip system includes a control apparatus, configured to support an optical communications apparatus in implementing functions in the foregoing aspects, for example, sending or processing data and/or information in the foregoing methods. In a possible design, the chip system further includes a memory, and the memory is configured to store a program instruction and data that are necessary for the optical communications apparatus. The chip system may include a chip, or may include a chip and another discrete component.

