Method, device and system for coexistence of 50G PON and FP ONU

Abstract

A 50G PON and FP ONU coexistence method, device and system relate to the technical field of optical access network multi-generation PON coexistence, and the method comprises the following steps: for all optical signal intensities sent by an FP ONU, calculating a ratio [beta] fponun of the optical signal intensity leaked to a 50G PON detector due to wavelength overlapping to the optical signal intensity detected by an EPON detector, and calculating the [beta] fponun through optical power or signal amplitude; setting a reverse amplification proportion according to the beta fponun, and amplifying the electric signal detected by the EPON detector according to the reverse proportion to obtain an amplification result SFP2; and performing interference offset on the electric signal S1 and the SFP2 detected by the 50G PON detector. According to the invention, the influence of the FP ONU on the 50G PON detector is eliminated, the purpose of interference cancellation is achieved, and the coexistence of the 50G PON ONU and the FP ONU is realized.

Description

Technical Field

[0001] This application relates to the technical field of multi-generation PON coexistence in optical access networks, and particularly relates to a method, device, and system for coexistence of 50G PON and FP ONU. Background Art

[0002] Due to the continuous enrichment of telecommunication services, users' demand for access network bandwidth is also increasing day by day. Fiber access has become the primary choice for Fiber to the Home (FTTH) because it is suitable for long-distance transmission and has rich bandwidth resources. In broadband access networks, Passive Optical Network (PON) technology is widely used. The PON technology is a point-to-multipoint fiber access technology, which consists of an Optical Line Terminal (OLT) on the central office side, an Optical Network Unit (ONU) on the user side, and an Optical Distribution Network (ODN).

[0003] With the continuous development of PON technology, 50-Gigabit-Capable PON has become the top choice for the next generation of PON technology after Ethernet PON (EPON), Gigabit-Capable PON (GPON), 10-Gigabit-Capable PON (XG PON), and 10-Gigabit-Capable Symmetric PON (XGS PON). It is of great significance to handle the transition between the old and new PON technologies.

[0004] The PON system uses broadcast technology for the downstream data stream and TDMA (Time Division Multiple Access) technology for the upstream data stream to solve the multiplexing problem of signals in each direction for multiple users. As Figure 1As shown, the uplink wavelength range of GPON DFB ONU is 1310±20nm, the uplink wavelength range of EPON DFB ONU is 1310±20nm, the uplink wavelength range of EPON FP ONU is 1310±50nm, and the uplink wavelength range of 10G EPON FP ONU is 1310±50nm. Due to historical deployment reasons, there are still a large number of FP (Fabry-Perot) laser ONUs (hereinafter referred to as FP ONUs) in the operator's existing network. Due to the limitations of the optical chip implementation principle, FP lasers have the characteristic of multiple longitudinal modes and occupy a relatively wide uplink wavelength band (1310±50nm), which conflicts with the uplink wavelength (1286±2nm) and downlink wavelength (1342±2nm) of the DFB (Distributed Feedback Laser) laser ONU (hereinafter referred to as DFB ONU) used by 50G PON, thus affecting the 50G PON signal. Summary of the Invention

[0005] This application provides a method, device and system for coexistence of 50G PON and FP ONU, which can solve the technical problem that FP ONU affects the 50G PON signal in the prior art and realize the coexistence of 50G PON ONU and FP ONU.

[0006] In the first aspect, an embodiment of this application provides a method for coexistence of 50G PON and FP ONU, and the method includes: The OLT discovers the FP ONU, and for all optical signal intensities sent by the FP ONU, calculates the ratio β of the optical signal intensity leaking into the 50G PON detector due to wavelength overlap of the FP ONU and the optical signal intensity detected by the EPON detector. fponu_n , the β fponu_n is calculated by optical power or signal amplitude; According to β fponu_n Set the reverse amplification ratio, and amplify the electrical signal detected by the EPON detector in reverse proportion to obtain the amplification result SFP2; Perform interference cancellation on the electrical signals S1 and SFP2 detected by the 50G PON detector.

[0007] Combined with the first aspect, in an implementation, the OLT receives the uplink optical signals from different ONUs. A part of the optical signals with a wavelength range of 1286±2nm enter the 50G PON detector, and the split optical signals of the other part are filtered to remove the part with a wavelength range of 1342±2nm and then enter the EPON detector.

[0008] In combination with the first aspect, in one embodiment, the OLT discovers the FP ONU, including: When the 10G / 1G EPON MAC of the OLT opens the silent window to complete the discovery and ranging of a new ONU, if the optical signal intensity detected by the 50G PON detector changes, the newly added ONU is the FP ONU, and the change amount of the optical signal intensity is the optical signal intensity leaked to the 50G PON detector due to the wavelength overlap of the FP ONU.

[0009] In combination with the first aspect, in one embodiment, the OLT discovers the FP ONU, including: When the 50G PON MAC of the OLT opens the silent window and no new 50G PON ONU joins, if the optical signal intensity received by the 50G PON detector is not close to 0, it is found that the online ONU is the FP ONU, and the change amount of the optical signal intensity is the optical signal intensity leaked to the 50G PON detector due to the wavelength overlap of the FP ONU.

[0010] In combination with the first aspect, in one embodiment, when the 50G PON MAC of the OLT opens the silent window, if a relevant message indicating the joining of a new 50G PON ONU is received, it is determined that a new 50G PON ONU has joined; if the relevant message is not received, it is determined that no new 50G PON ONU has joined.

[0011] In combination with the first aspect, in one embodiment, the OLT discovers the FP ONU, including: The EPON detector and the 50G PON detector at the OLT continuously monitor the signal intensity of the upstream optical signal from the ONU. When the EPON detector detects that the optical signal intensity suddenly rises from close to 0 and then gradually decreases to close to 0; at the same time, when the 50G PON detector detects that the optical signal intensity also rises and then decreases synchronously, the ONU is the FP ONU.

[0012] In combination with the first aspect, in one embodiment, create a table that contains all ONU IDs of the FP ONU type at the ONU side and the corresponding β one by one fponu_n ; After the OLT discovers the FP ONU, obtain the ONU ID of the FP ONU, and calculate the corresponding β by looking up the table fponu_n .

[0013] In combination with the first aspect, in one embodiment, when the 50G PON MAC of the OLT opens the silent window and no new 50G PON ONU joins, the change amount of the optical signal intensity is detected by the 50G PON detector, and β is continuously corrected in combination with the optical signal intensity detected by the EPON detector. fponu_n The corresponding ONU ID and its β are recorded. fponu_n The table is formed.

[0014] In combination with the first aspect, in one embodiment, the optical signal intensity is reflected by the optical power detected by the detector; Or it is reflected by the signal amplitude after the optical signal detected by the detector is amplified.

[0015] In combination with the first aspect, in one embodiment, the process of obtaining the amplification result S FP2 and the process of canceling the interference between the electrical signal S 1 detected by the 50G PON detector and S FP2 are implemented by an analog circuit or by a digital algorithm inside the DSP.

[0016] In a second aspect, an embodiment of the present application provides a device based on the method for coexistence of 50G PON and FP ONU according to any one of the above, and the device includes: A signal control unit, which is used to calculate the ratio β of the optical signal intensity leaking into the 50G PON detector due to wavelength overlap and the optical signal intensity detected by the EPON detector for all the optical signal intensities sent by the FP ONU when the OLT discovers the FP ONU. fponu_n ; A reverse ratio amplification unit, which is used to set a reverse amplification ratio according to β fponu_n and amplify the electrical signal detected by the EPON detector in reverse proportion to obtain an amplification result S FP2 ; An interference cancellation unit, which is used to cancel the interference between the electrical signal S 1 detected by the 50G PON detector and S FP2 ;

[0017] In a third aspect, an embodiment of the present application provides a system for coexistence of 50G PON and FP ONU, including: An EPON detector, which is used to detect the optical power of the FP optical signal; A 50G PON detector, which is used to detect the optical power of the FP optical signal leaking due to wavelength overlap and the optical power of the 50GPON optical signal; It further includes the above-mentioned device for calculating the ratio β of the optical signal intensity leaking into the 50G PON detector due to wavelength overlap to the optical signal intensity detected by the EPON detector. fponu_n ; Set the reverse amplification ratio according to β fponu_n to reversely amplify the electrical signal detected by the EPON detector in proportion to obtain the amplified result SFP2; perform interference cancellation on the electrical signals S1 and SFP2 detected by the 50G PON detector.

[0018] The beneficial effects brought by the technical solution provided in the embodiment of the present application include: Calculate the ratio β of the optical signal intensity leaking into the 50G PON detector due to wavelength overlap to the optical signal intensity detected by the EPON detector fponu_n , based on β fponu_n , by analyzing and processing the optical signal intensities detected by the EPON detector and the 50G PON detector at the OLT side, removing the influence of the FP ONU on the 50G PON detector, achieving the purpose of interference cancellation, and realizing the coexistence of the 50G PON ONU and the FP ONU. Description of the Drawings

[0019] Figure 1 is a wavelength schematic diagram of a passive optical network in the prior art; Figure 2 is a schematic diagram for judging the ONU type in the embodiment of the present application; Figure 3 is a schematic flow diagram of the method for coexistence of 50G PON and FP ONU in the embodiment of the present application; Figure 4 is a schematic diagram for realizing reverse proportional amplification and interference cancellation through the silent window mechanism in the embodiment of the present application; Figure 5 is a schematic diagram of another embodiment for realizing reverse proportional amplification and interference cancellation in the present application; Figure 6 is a schematic diagram for realizing reverse proportional amplification and interference cancellation through the signal amplitude of the electrical signal in the present application. Detailed Embodiments

[0020] In order to enable those skilled in the art to better understand the solution of the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without making creative efforts shall fall within the protection scope of the present application.

[0021] To make the objectives, technical solutions, and advantages of this application clearer, the following will further describe the embodiments of this application in detail with reference to the accompanying drawings.

[0022] As Figure 1 and Figure 2 shown, in the existing network deployment, there will be a coexistence situation of FP ONU, 50G PON ONU, EPON DFB ONU, etc. The OLT receives the upstream optical signals sent from different types of ONUs and enters different detectors through the filter. Among them, a part of the optical signals with a wavelength range of 1286 ± 2 nm enter the 50G PON detector; another part of the optical signals are filtered by the next filter to remove the part with a wavelength range of 1342 ± 2 nm to avoid the influence of downstream reflected light, and then enter the EPON detector. In this way, the wavelength range that can be detected by the EPON detector removes the optical signals with a wavelength range of 1342 ± 2 nm and 1286 ± 2 nm.

[0023] Under normal circumstances, the central wavelength of the FP ONU is near 1310 nm, and the energy loss of the longitudinal modes in the wavelength bands near 1342 nm and 1286 nm is small, which has little impact on the reception of the FP signal; in the extreme case, the sensitivity of the receiver needs to be increased by about 4 dB.

[0024] When the upstream signal is the optical signal sent by the 50G PON ONU, its upstream wavelength range is 1286 ± 2 nm, which can be detected by the 50G PON detector. Due to the filter, the EPON detector cannot detect the optical signals within the range of 1286 ± 2 nm. Therefore, the EPON detector does not detect the corresponding optical signals. If the upstream signal is sent by the EPON DFB ONU (such as 10G EPON upstream narrowing, EPON upstream narrowing), its upstream wavelength range is 1310 ± 20 nm, which has no impact on the 50G PON detector. However, if the upstream signal is the optical signal sent by the FP ONU, since its upstream wavelength range is 1310 ± 50 nm, when its longitudinal mode range crosses 1286 nm, in addition to part of the signal entering the EPON detector, a small part also enters the 50G PON detector, thus interfering with the 50G PON upstream signal in communication. To solve this problem, since the interference signal of 50G PON comes from the FP ONU, its correlation can be used to eliminate the interference of 50G PON by certain software and hardware means.

[0025] In this embodiment, different detectors are distinguished according to the detected wavelength range. The EPON detector can be used to detect the upstream optical signals of EPON DFB ONU and FP ONU; the 50G PON detector can be used to detect the upstream optical signals of 50G PON ONU, and can also detect a small part of the upstream optical signals leaked due to the wavelength overlap of FP ONU.

[0026] In a first aspect, an embodiment of the present application provides a method for coexistence of 50G PON and FP ONU.

[0027] In one embodiment, as Figure 3 shown, it is a schematic flowchart of an embodiment of the method for coexistence of 50G PON and FP ONU in the present application; the method includes: S1. The OLT discovers the FP ONU, and for all the optical signal intensities sent by the FP ONU, calculates the ratio β of the optical signal intensity leaked to the 50G PON detector due to the wavelength overlap of the FP ONU and the optical signal intensity detected by the EPON detector. fponu_n β fponu_n is calculated through the optical power or signal amplitude. The optical signal intensity can be reflected by the optical power detected by the detector, and can also be reflected by the signal amplitude after the optical signal detected by the detector is amplified.

[0028] In this embodiment, β fponu_n can be regarded as a parameter. When using the optical power to reflect the optical signal intensity, the calculation formula of β fponu_n is as follows: β fponu_n = (1) where ∆RSSI_50G PON is the optical power leaked to the 50G PON detector due to the wavelength overlap of the FP ONU, and RSSI_FP is the optical power detected by the EPON detector.

[0029] S2. According to β fponu_n set the reverse amplification ratio, and amplify the electrical signal detected by the EPON detector in reverse proportion to obtain the amplified result S FP2 .

[0030] S FP2 = -(β fponu_n ×S FP ) = -S FP_noise (2) where S FP is the electrical signal received and amplified by the EPON detector, and the amplified result S FP2 can be used to eliminate the interference caused by the FP ONU to the 50G PON. S FP_noiseFor example, Figure 4 As shown, in this embodiment, the amplification factor for amplifying the electrical signal detected by the EPON detector is the same as that for amplifying the electrical signal detected by the 50G PON detector. In other embodiments, the parameters can also be corrected using different amplification factors to obtain S FP2 = -S FP_noise . During the communication process, when the upstream optical signals sent by the FP ONU and the 50G PON ONU are transmitted to the OLT, the optical signal entering the 50G PON detector is composed of the 50G PON optical signal and the optical signal leaked from the FP. Let the signal obtained after amplification be represented by S 1 , as shown in Equation (3): S 1 = S 50G + S FP_noise (3) Where S 50G represents the electrical signal after the optoelectronic conversion of the 50G PON optical signal, and S FP_noise represents the electrical signal corresponding to the interference caused by the leakage of the FP optical signal. At the EPON detector, the optical power RSSI_FP can be obtained. After being amplified and processed by Equation (2), the influence part S FP2 of the FP ONU on the 50G PON is obtained.

[0031] S3. Perform interference cancellation on the electrical signals S 1 and S FP2 detected by the 50G PON detector. After the interference cancellation process, the part of the FP ONU upstream signal light leaked into the 50G PON detector is removed to obtain the 50G PON electrical signal, as shown in Equation (4): S 0 = S 1 +S FP2 = S 50G (4) In this way, the influence of the FP ONU on the 50G PON detection is removed, thus achieving the coexistence of the FP ONU and the 50G PON ONU.

[0032] For example, Figure 4 As shown, it is a schematic diagram of the present application achieving reverse proportional amplification and interference cancellation through the silent window mechanism. When the TDM PON is working, the silent window will be opened regularly to complete the discovery and ranging of new ONUs. If no new ONUs are added, the optical power received by the OLT during the silent period is close to 0. In this embodiment, the OLT can discover the FP ONU in two ways.

[0033] The first way is: When the 10G / 1G EPON MAC of the OLT opens the silent window to complete the discovery and ranging of a new ONU, if the optical signal intensity detected by the 50G PON detector changes, the newly added ONU is an FP ONU, and the change amount of the optical signal intensity is the optical signal intensity leaked to the 50G PON detector due to wavelength overlap.

[0034] In this embodiment, when the silent window opened by the 10G / 1G EPON MAC of the OLT, if the newly added ONU is an FP ONU, it will cause the received optical power RSSI_50G PON of the 50G PON detector to change, indicating that the longitudinal mode of the wavelength of this ONU leaks to the 50G PON detector. Record the ONU ID and MAC address or serial number SN at this time, and it is also found that the newly added ONU is an FP ONU. The change amount of the optical power is the above-mentioned ∆RSSI_50G PON, that is, S FP_noise 。

[0035] The second method is: When the 50G PON MAC of the OLT opens the silent window and no new 50G PON ONUs are added, if the optical signal intensity received by the 50G PON detector is not close to 0, it is found that the online ONU is an FP ONU, and the change amount of the optical signal intensity is the optical signal intensity leaked to the 50G PON detector due to wavelength overlap. Among them, the online ONU is an ONU that has been added and is transmitting data. During the silent window stage of 50G PON, if a new 50G PON ONU is added, the OLT will receive relevant messages; therefore, the OLT can judge whether a new 50G PON ONU is added by receiving relevant messages.

[0036] In this embodiment, when the 50G PON MAC of the OLT opens the silent window and no new 50G PON ONUs are added, RSSI_50G PON should be close to 0. If it is not close to 0, the change amount is ∆RSSI_50G PON, then the wavelength of the corresponding FP ONU overlaps with the wavelength of the 50G PON ONU. Record the ONU ID at this time, and it is found that the online ONU is an FP ONU. At the same time, the received optical power of the EPON optical signal detector is RSSI_FP.

[0037] Both methods in this embodiment can identify FP ONUs. In actual operation, these two methods can be used to detect FP ONUs in the existing network and replace them, which can also avoid FP ONUs interfering with 50G PON. In addition, both of the above methods can calculate ∆RSSI_50G PON based on the optical power change of the 50G PON detector. However, in the second method, since it starts changing from close to 0, calculating ∆RSSI_50G PON in the second method is more straightforward than the first method.

[0038] As Figure 4 shown, in this embodiment, when the 10G / 1G EPON MAC opens the silent window to determine whether the newly added ONU is an FP ONU, the basis for judgment is whether the signal strength detected by the 50G PON detector at the OLT end has changed. If the RSSI_50G PON detected by the 50G PON detector remains unchanged, then the newly added ONU is not an FP ONU; if the RSSI_50G PON detected by the 50G PON detector changes, then the newly added ONU is an FP ONU. The signal control unit can calculate ∆RSSI_50G PON based on the above RSSI_50G PON. Combining with RSSI_FP, the signal control unit outputs β fponu_n . Then, the optical signal received by the EPON detector is amplified by the EPON amplification unit to obtain S FP , and is inversely proportionally amplified through the inverse proportional amplification unit and β fponu_n output by the signal control unit to obtain the output result S FP2 of the inverse proportional unit.

[0039] Since the optical signal entering the 50G PON detector is composed of the 50G PON optical signal and the optical signal leaked by the FP, the signal obtained after being amplified by the 50G PON amplification unit is S 1 . Finally, by performing interference cancellation processing on S FP2 and S 1 , the part of the optical leakage from the FP ONU upstream to the 50G PON detector is removed, eliminating the influence of the FP ONU on the 50G PON detection, thus achieving the coexistence of the FP ONU and the 50G PON ONU. Among them, the amplification factors of the EPON amplification unit and the 50G PON amplification unit are the same.

[0040] Furthermore, in one embodiment, a table can be created in advance, which contains the ONU IDs of all types of FP ONUs at the ONU end and the corresponding β fponu_nAfter the OLT discovers the FP ONU, it obtains the ONU ID of the FP ONU and finds the corresponding β fponu_n .

[0041] In this embodiment, when the 50G PON MAC of the OLT opens the silent window and no new 50G PON ONU is added, the FP ONU is continuously discovered. According to the results detected by the EPON detector and the 50G PON detector, β is continuously corrected by the above formula (1). fponu_n ; Record the corresponding ONU ID and its β fponu_n , forming a β fponu_n Parameter table, which contains the IDs of all FP ONUs on the ONU side and their corresponding β fponu_n Specifically, the change in optical power received by the 50G PON detector is ∆RSSI_50G PON, which is continuously corrected by combining RSSI_FP. fponu_n .

[0042] like Figure 4 As shown in the figure, during the interference cancellation process, the 10G / 1G EPON MAC receives the upstream light from the ONU and uses the previous β fponu_n β formed by the parameter acquisition process fponu_n Parameter table, find the β corresponding to the ONU ID fponu_n , through the signal control unit to fponu_n The parameters are output to the reverse proportional amplifier unit to set the corresponding amplification ratio. The reverse proportional amplifier converts the electrical signal S detected and processed by the EPON detector into FP Reverse proportional amplification to obtain S FP2 The signal entering the 50G PON detector is the 50G PON optical signal doped with the FP optical signal. According to formula (3), the processed signal is S 1 . 1 and S FP2 Interference cancellation is performed to obtain a 50G PON electrical signal, as shown in formula (4), thus completing the entire interference cancellation process.

[0043] Furthermore, in the above-mentioned embodiments, the process of obtaining the amplification result SFP2 and the electrical signal S 1 and S FP2 The process of interference cancellation can be implemented by using analog circuits or digital algorithms inside DSP.

[0044] like Figure 5 As shown, a method is provided to obtain β without using a silent window mechanism.fponu_n In the method embodiment, loose coupling between the optical module and the PON MAC can be achieved. The EPON detector and the 50G PON detector continuously monitor the signal intensity of the upstream optical signal from the ONU. When the EPON detector detects that the optical signal intensity suddenly rises from close to 0 and then gradually decreases to close to 0; at the same time, when the 50G PON detector detects that the optical signal intensity also rises and then decreases synchronously, then the ONU is an FP ONU.

[0045] In this embodiment, the EPON detector and the 50G PON detector at the OLT continuously monitor the optical power of the upstream optical signal from the ONU, denoted as RSSI_FP and RSSI_50GPON respectively. When a data block is suddenly transmitted by a certain FP ONU, when the burst data starts to be transmitted, the online RSSI_FP monitored by the EPON detector will suddenly rise from close to 0. When the burst data transmission ends, it will be found that the online RSSI_FP monitored by the EPON detector gradually decreases to close to 0; if at the same time, the RSSI_50G PON monitored by the 50GPON detector also rises and then decreases synchronously, it means that the ONU at this time is an FP ONU. Record the change amount of the signal intensity monitored by the 50G PON detector at this time as ΔRSSI_50G PON, then β fponu_n can be obtained by using the above formula (1). Record β fponu_n and the corresponding ONU ID to form a look-up table. The subsequent reverse proportional amplification and interference cancellation processes are the same as the methods used in the above embodiments.

[0046] As Figure 6 shown, an embodiment of realizing reverse proportional amplification and interference cancellation through the signal amplitude of an electrical signal is provided. In this embodiment, the optical signal intensity is reflected by the signal amplitude. The method of calculating β fponu_n is different from that of the above embodiment, and specifically includes: after the optical signal RSSI_FP detected by the EPON detector is photoelectrically converted, it is amplified to obtain the signal amplitude AM_FP of the corresponding electrical signal; after the optical signal RSSI_50GPON detected by the 50G PON detector is photoelectrically converted, it is amplified to obtain the signal amplitude AM_50G PON of the corresponding electrical signal. According to the 50G PON detector, the signal amplitude ∆AM_50G PON leaked to the 50GPON detector due to wavelength overlap is obtained. Through ∆AM_50G PON and AM_FP, β is obtained according to the following formula fponu_n : β fponu_n = .

[0047] In this embodiment, the process of determining that an ONU is an FP ONU is similar to the above embodiment. When the silent window of the 10G / 1G EPON MAC of the OLT is open, if the newly added ONU is an FP ONU, it will cause a change in the signal amplitude AM_50G PON obtained after amplification by the 50G PON detector, indicating that the longitudinal mode of the wavelength of this ONU leaks into the 50G PON detector. Record the ONU ID and MAC address or serial number SN at this time, and it is also found that the newly added ONU is an FP ONU. The change amount of the signal amplitude is the above-mentioned ∆AM_50G PON.

[0048] Alternatively, when the silent window of the 50G PON MAC of the OLT is open and no new 50G PON ONUs are added, if the signal amplitude AM_50G PON received and amplified by the 50G PON detector is not close to 0, it is found that the online ONU is an FP ONU, and the change amount of the signal amplitude is the above-mentioned ∆AM_50G PON. In this embodiment, through ∆AM_50G PON, β is continuously corrected in combination with the above-mentioned AM_FP fponu_n , record the corresponding ONU ID and its β fponu_n , form a table, and then the β corresponding to the ONU ID can be found by looking up the table fponu_n .

[0049] In addition, after the EPON detector and 50G PON detector at the OLT continuously monitor the upstream optical signal from the ONU for photoelectric conversion and then amplify it to obtain the signal amplitude of the corresponding electrical signal, when the signal amplitude obtained by the EPON detector suddenly rises from being close to 0 and then gradually decreases to being close to 0; at the same time, the signal amplitude obtained by the 50G PON detector also rises and then decreases synchronously, then it can also be determined that this ONU is an FP ONU.

[0050] In a second aspect, based on the above method embodiment, a device embodiment for coexistence of 50G PON and FP ONU is provided. The device includes a signal control unit, a reverse proportional amplification unit, and an interference cancellation unit.

[0051] The signal control unit is used to calculate the ratio β of the optical signal intensity leaking into the 50G PON detector due to wavelength overlap of the FP ONU and the optical signal intensity detected by the EPON detector for all optical signal intensities sent by the FP ONU when the OLT discovers the FP ONU fponu_n .

[0052] The reverse proportional amplification unit is used to set a reverse amplification ratio according to β fponu_n and reverse proportionally amplify the electrical signal detected by the EPON detector to obtain an amplification result S FP2 .

[0053] An interference cancellation unit for canceling interference of the electrical signals S 1 and S FP2 detected by a 50G PON detector.

[0054] Wherein, the function implementation of each module in the above device corresponds to each step in the above method embodiment, and its function and implementation process will not be elaborated here one by one.

[0055] In a third aspect, a system for coexistence of 50G PON and FP ONU is provided, the system includes an EPON detector, a 50G PON detector and the device in the above embodiment.

[0056] The EPON detector is used to detect the optical power of the FP optical signal.

[0057] The 50G PON detector is used to detect the optical power of the FP optical signal leaked due to wavelength overlap of the FP ONU and the optical power of the 50G PON optical signal.

[0058] The device in the above embodiment is used to calculate the ratio β of the optical signal intensity leaked to the 50G PON detector due to wavelength overlap and the optical signal intensity detected by the EPON detector fponu_n ; set the reverse amplification ratio according to β fponu_n to reversely amplify the electrical signal detected by the EPON detector by a proportionality to obtain the amplified result S FP2 ; cancel the interference of the electrical signals S 1 and S FP2 detected by the 50G PON detector.

[0059] The system in this embodiment calculates β fponu_n , removes the influence of the FP ONU on the 50G PON detector by analyzing and processing the optical signal intensities detected by the EPON detector and the 50G PON detector at the OLT end, and achieves the purpose of interference cancellation. Compared with the conventional method, it makes full use of the existing PON software and hardware architecture, effectively utilizes a large number of FP ONUs of operators, and significantly reduces the cost and power consumption.

[0060] It should be noted that the serial numbers of the above embodiments of the present application are only for description and do not represent the advantages and disadvantages of the embodiments.

[0061] In the description of the specification, claims and the above drawings of this application, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but may optionally further include steps or units not listed, or may optionally further include other steps or units inherent to these processes, methods, products or devices. The descriptions such as "first", "second" and "third" are used to distinguish different objects, etc., and do not represent a sequence, nor do they limit that "first", "second" and "third" are different types.

[0062] In the description of the embodiments of this application, words such as "exemplary", "for example" or "for instance" are used to indicate examples, illustrations or explanations. Any embodiment or design solution described as "exemplary", "for example" or "for instance" in the embodiments of this application should not be construed as being more preferred or having more advantages than other embodiments or design solutions. Rather, the use of words such as "exemplary", "for example" or "for instance" is intended to present relevant concepts in a specific manner.

[0063] In the description of the embodiments of this application, unless otherwise specified, " / " means "or". For example, A / B may mean A or B; "and / or" in the text is merely a description of the association relationship between associated objects, indicating that there can be three relationships. For example, A and / or B may mean: A exists alone, A and B exist simultaneously, and B exists alone. In addition, in the description of the embodiments of this application, "a plurality of" means two or more than two.

[0064] In some processes described in the embodiments of this application, a plurality of operations or steps appear in a specific order. However, it should be understood that these operations or steps may not be executed in the order in which they appear in the embodiments of this application or may be executed in parallel. The serial numbers of the operations are only used to distinguish different operations, and the serial numbers themselves do not represent any order of execution. In addition, these processes may include more or fewer operations, and these operations or steps may be executed in order or in parallel, and these operations or steps may be combined.

[0065] Through the description of the above embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus a necessary general hardware platform. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation. Based on such an understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium as described above (such as ROM / RAM, magnetic disk, optical disc), and includes several instructions to enable a terminal device to execute the methods described in the various embodiments of this application.

[0066] The above are only the preferred embodiments of the present application, and do not limit the patent scope of the present application accordingly. Any equivalent structure or equivalent process transformation made by using the content of the specification and drawings of the present application, or directly or indirectly applied in other related technical fields, shall similarly be included within the patent protection scope of the present application.

Claims

1. A method for coexistence of 50G PON and FP ONU, characterized in that: The method comprises: The OLT discovers the FP ONU and calculates the ratio of the optical signal strength leaked to the 50G PON detector due to the wavelength overlap of the FP ONU to the optical signal strength detected by the EPON detector. fponu_n , the β fponu_n Calculated by optical power or signal amplitude; According to β fponu_n Set the reverse amplification ratio to reversely amplify the electrical signal detected by the EPON detector to obtain the amplification result S FP2 ; The electrical signals S1 and S detected by the 50G PON detector are FP2 Perform interference cancellation.

2. The method for coexistence of 50G PON and FP ONU according to claim 1, characterized in that: The OLT receives upstream optical signals from different ONUs. A portion of the optical signal with a wavelength range of 1286±2nm enters the 50GPON detector, and the other portion of the split optical signal is filtered out by a filter to remove the portion with a wavelength range of 1342±2nm, and then enters the EPON detector.

3. The method for coexistence of 50G PON and FP ONU according to claim 1, characterized in that: The OLT discovers the FPONU, including: When the 10G / 1G EPON MAC of the OLT opens the silent window to complete the discovery and ranging of the new ONU, if the optical signal strength detected by the 50G PON detector changes, the newly added ONU is an FP ONU, and the change in the optical signal strength is the optical signal strength leaked to the 50G PON detector due to the wavelength overlap of the FP ONU.

4. The method for coexistence of 50G PON and FP ONU according to claim 1, characterized in that: The OLT discovers the FPONU, including: When the 50G PON MAC of the OLT opens the silent window and no new 50G PON ONU is added, if the optical signal strength received by the 50G PON detector is not close to 0, it is found that the online ONU is an FP ONU. The change in the optical signal strength is the optical signal strength leaked to the 50G PON detector due to the wavelength overlap of the FP ONU.

5. The method for coexistence of 50G PON and FP ONU as claimed in claim 1, characterized in that : When the 50G PON MAC of the OLT opens the silent window, if a related message about the addition of a new 50G PON ONU is received, it is determined that a new 50G PON ONU has been added; if the related message is not received, it is determined that no new 50G PON ONU has been added.

6. The method for coexistence of 50G PON and FP ONU according to claim 1, characterized in that: The OLT discovers the FPONU, including: The EPON detector and 50G PON detector at the OLT continuously monitor the signal strength of the upstream light from the ONU. When the EPON detector detects that the optical signal strength suddenly increases from close to 0 and then gradually decreases to close to 0; at the same time, the 50G PON detector detects that the optical signal strength also increases and then decreases synchronously, then the ONU is an FP ONU.

7. The method for coexistence of 50G PON and FP ONU according to claim 1, characterized in that: Create a table that contains the ONU IDs of all FP ONUs on the ONU side and the corresponding β fponu_n ; After the OLT discovers the FP ONU, it obtains the ONU ID of the FP ONU and calculates the corresponding β by searching the table. fponu_n .

8. The method for coexistence of 50G PON and FP ONU according to claim 7, characterized in that: When the 50G PON MAC of the OLT opens the silent window and no new 50G PON ONU is added, the 50G PON detector detects the change in the optical signal strength and continuously corrects the β value based on the optical signal strength detected by the EPON detector. fponu_n , record the corresponding ONU ID and its β fponu_n , forming the table.

9. The method for coexistence of 50G PON and FP ONU according to claim 1, characterized in that: The intensity of the optical signal is reflected by the optical power detected by the detector; Alternatively, it is reflected by the signal amplitude after the light detected by the detector is amplified.

10. The method for coexistence of 50G PON and FP ONU according to claim 1, characterized in that: The obtained amplification result S FP2 The process of detecting the electrical signals S1 and S FP2 The interference cancellation process is implemented using analog circuits or digital algorithms within the DSP.

11. A device based on the method for coexistence of 50G PON and FP ONU according to any one of claims 1 to 10, characterized in that: The device comprises: The signal control unit is used to calculate the ratio β of the optical signal strength leaked to the 50G PON detector due to wavelength overlap and the optical signal strength detected by the EPON detector for all optical signal strengths sent by the FP ONU when the OLT discovers the FP ONU. fponu_n ; The inverse proportional amplification unit is used to fponu_n Set the reverse amplification ratio to reversely amplify the electrical signal detected by the EPON detector to obtain the amplification result S FP2 ; The interference cancellation unit is used to convert the electrical signals S1 and S FP2 Perform interference cancellation.

12. A system in which 50G PON and FP ONU coexist, characterized in that: include: EPON detector, which is used to detect the optical power of the FP optical signal; 50G PON detector, which is used to detect the optical power of the FP optical signal leaked due to wavelength overlap and the optical power of the 50G PON optical signal; The device according to claim 11 is used to calculate the ratio β of the optical signal strength leaked to the 50G PON detector due to wavelength overlap and the optical signal strength detected by the EPON detector. fponu_n According to β fponu_n Set the reverse amplification ratio to reversely amplify the electrical signal detected by the EPON detector to obtain the amplification result S FP2 ; The electrical signals S1 and S detected by the 50G PON detector FP2 Perform interference cancellation.

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