CN102143059A - Uplink broadband allocation method, system and equipment for 10G Ethernet passive optical network (EPON) - Google Patents

Abstract

Embodiments of the present invention provide a 10G EPON bandwidth allocation method, system and device. The method includes: judging whether the uplink wavelengths of the first ONU and the second ONU with different uplink data rates overlap; if the uplink wavelengths do not overlap, assign the first ONU and the second ONU wavelength division multiplexing bandwidth so that the first optical network unit and the second optical network unit use wavelength division multiplexing to send uplink signals; if the uplink wavelengths overlap, the first optical network unit and the second optical network unit The second ONU allocates time-division multiplexing bandwidth, so that the uplink signal is sent between the first ONU and the second ONU in a time-division multiplexing manner. The embodiment of the present invention can make full use of the uplink bandwidth, increase the uplink transmission capacity of the system, and improve the utilization rate of the uplink bandwidth.

Description

10G EPON uplink bandwidth allocation method, system and device

technical field

The present invention relates to passive optical network technology, in particular to a 10G Ethernet Passive Optical Network (10G Ethernet Passive Optical Network, 10G EPON) uplink bandwidth allocation method, system and device.

Background technique

A passive optical network usually includes at least one optical line terminal (Optical Line Terminal, OLT) located at the central office, a plurality of optical network units (Optical Network Unit, ONU) located at the far end, and an optical network unit (ONU) arranged between the OLT and the ONU. Optical Distribution Network (ODN) for distributing/multiplexing data. Wherein the point-to-multipoint connection is implemented between the OLT and the ONU through the ODN, so that the multiple ONUs share an optical transmission channel, wherein the optical signal propagating from the OLT to the ONU direction is the downlink direction , using the broadcast method to transmit data; the optical signal propagating in the direction from ONU to OLT is the uplink direction.

10 Gigabit Ethernet Passive Optical Network (10G EPON) is a next-generation Ethernet-based high-speed (10G data rate) passive optical network system evolved from the traditional Ethernet Passive Optical Network (EPON) system. It can support the access of various types of optical network units, including compatibility with optical network units with a data rate of 1G in the traditional EPON system. Specifically, the OLT at the local end of the 10G EPON system can not only support the access of symmetrical 10G EPON ONUs with uplink and downlink data rates of 10G, but also support asymmetric 10G EPON ONUs with uplink and downlink data rates of 1G and 10G respectively. In addition, the central office OLT can also support the access of traditional EPON ONUs with both uplink and downlink data rates of 1G. For the convenience of description, the following ONUs with an upstream data rate of 1G (including asymmetric 10G EPON ONUs and traditional EPON ONUs) are recorded as 1G ONUs, and ONUs with an upstream data rate of 10G (ie, symmetrical 10G EPON ONUs) are recorded as 10G ONUs. Among them, the wavelength range of the upstream signal of 1G ONU is 1260nm-1360nm, and the center wavelength is 1310nm; the wavelength range of the upstream signal of 10G ONU is 1260nm-1280nm, and the center wavelength is 1270nm.

The existing 10G EPON system considers the compatibility of the traditional EPON ONU, so in the uplink direction, the 10G ONU and the 1G ONU use the time division multiplexing (TDM, Time Division Multiplexing) bandwidth allocated by the OLT at the central office. The TDM communication method sends uplink data, that is, only one ONU sends uplink data at the same time, which may be 10G or 1G. However, due to the time-division multiplexing communication method, the upstream channel bandwidth of the existing 10G EPON system will be severely restricted by the traditional EPON ONU and the asymmetric 10G EPON ONU, and it is impossible to truly achieve the high bandwidth of the upstream 10G. Some 10G EPON systems have low bandwidth utilization of the uplink channel.

Contents of the invention

Embodiments of the present invention provide a 10G EPON uplink bandwidth allocation method and a 10G EPON system and device with high bandwidth utilization in order to solve the problem of low bandwidth utilization of the uplink channel in the prior art 10G EPON system .

In order to achieve the above object, an embodiment of the present invention firstly provides a method for allocating uplink bandwidth of a 10G EPON system, the method comprising: judging whether the uplink wavelengths of the first ONU and the second ONU with different uplink data rates overlap ; allocate uplink bandwidth to the first ONU and the second ONU according to the judgment result; wherein, if the uplink wavelengths of the first ONU and the second ONU do not overlap, The first optical network unit and the second optical network unit allocate wavelength division multiplexing bandwidth, so that the first optical network unit and the second optical network unit use wavelength division multiplexing to send uplink signals; If the uplink wavelengths of the first optical network unit and the second optical network unit overlap, allocate time-division multiplexing bandwidth to the first optical network unit and the second optical network unit, so that the first optical network unit The uplink signal is sent between the network unit and the second optical network unit in a time division multiplexing manner.

An embodiment of the present invention also provides an optical line terminal, which includes: a wavelength judging unit, configured to judge whether the uplink wavelengths of the first optical network unit and the second optical network unit with different uplink rates overlap; a bandwidth allocation unit, configured according to The judgment result of the wavelength judging unit allocates uplink bandwidth to the first ONU and the second ONU; wherein, the bandwidth allocating unit judges that the first ONU and the second ONU are When the uplink wavelengths of the second optical network unit do not overlap, allocate wavelength division multiplexing bandwidth to the first optical network unit and the second optical network unit so that the first optical network unit and the second optical network unit Uplink signals are sent between network units in a wavelength division multiplexing manner; when the wavelength judging unit judges that the uplink wavelengths of the first optical network unit and the second optical network unit overlap, the first optical network unit The time-division multiplexing bandwidth is allocated between the unit and the second optical network unit, so that uplink signals are sent between the first optical network unit and the second optical network unit in a time-division multiplexing manner.

An embodiment of the present invention also provides an optical access system, which includes a central office device and multiple remote devices, wherein the central office device is coupled to the multiple remote devices in a point-to-multipoint manner; the The multiple remote devices include a first remote device and a second remote device with different uplink data rates, which are respectively used to send a first uplink signal and a second uplink signal to the central office device; To determine whether the uplink wavelengths of the first remote device and the second remote device overlap, and assign wavelength division multiplexing to the first remote device and the second remote device when the uplink wavelengths do not overlap. using a bandwidth to transmit the first uplink signal and the second uplink signal in a wavelength division multiplexing manner between the first remote device and the second remote device, and when the uplink wavelengths overlap The first remote device and the second remote device allocate time-division multiplexing bandwidth so that the first remote device and the second remote device transmit the first uplink signal in a time-division multiplexed manner and the second uplink signal.

In the embodiment of the present invention, bandwidth allocation is performed according to the judgment result of whether wavelength overlap occurs between the first optical network unit and the second optical network unit with different uplink data rates, and the wavelength division multiplexing bandwidth is allocated when the uplink wavelengths do not overlap so that the first The optical network unit and the second optical network unit transmit uplink signals in a wavelength-division multiplexing manner, and allocate time-division multiplexing bandwidth when the upstream wavelengths overlap so that the first optical network unit and the second optical network unit transmit uplink signals in a time-division multiplexing manner . Through the bandwidth allocation method described above, the embodiment of the present invention can make full use of the high bandwidth of the uplink by using the wavelength division multiplexing method, greatly improving the uplink transmission capacity of the system, thereby improving the utilization rate of the uplink bandwidth.

Description of drawings

The drawings described here are used to provide further understanding of the present invention, constitute a part of the application, and do not limit the present invention. In the attached picture:

Figure 1 is a schematic structural diagram of a 10G EPON system;

Fig. 2 is the flowchart of the uplink bandwidth allocation method of the 10G EPON system of the embodiment of the present invention;

Fig. 3 is a schematic flow chart of the steps of judging whether the wavelengths overlap in the method shown in Fig. 2;

4 is a schematic structural diagram of an optical module of an optical line terminal according to an embodiment of the present invention;

Fig. 5 is a schematic diagram of transmission of uplink signals when time division multiplexing and wavelength division multiplexing are adopted according to an embodiment of the present invention;

Fig. 6 is a schematic diagram of the transmission of uplink signals after adopting the identification according to the embodiment of the present invention;

FIG. 7 is a schematic structural diagram of an optical line terminal according to an embodiment of the present invention;

FIG. 8 is a schematic structural diagram of a wavelength judging unit of the optical line terminal shown in FIG. 7 .

Detailed ways

In order to make the object, technical solution and advantages of the present invention clearer, the embodiments of the present invention will be further described in detail below in conjunction with the accompanying drawings. Here, the exemplary embodiments and descriptions of the present invention are used to explain the present invention, but not to limit the present invention.

Please refer to Figure 1, which is a schematic diagram of the structure of a 10G EPON system. The 10G EPON system is a point-to-multipoint optical access system, and may have an architecture as defined in the IEEE 802.3av standard. The entire content of the IEEE 802.3av standard is incorporated in this application document by reference. Specifically, the 10G EPON system may include at least one optical line terminal (OLT) located at the central office, a plurality of optical network units (ONUs) located at the remote end, and an optical network unit (ONU) arranged between the optical line terminal and the optical network unit Optical distribution network (ODN) for distributing/multiplexing data among them. Wherein, the optical line terminal may be an optical line terminal defined by the 10G EPON standard, that is, a 10G EPON OLT, which is connected to the plurality of optical network units in a point-to-multipoint manner through the optical distribution network, and the optical The distribution network implements data distribution/multiplexing through passive optical devices (such as optical splitters). Wherein, the direction from the optical line terminal to the optical network unit is a downlink direction, and the direction from the optical network unit to the optical line terminal is an uplink direction, and the optical line terminal adopts a broadcast mode in the downlink direction transmit downlink data, and in the uplink direction, the ONU transmits uplink data to the OLT within the bandwidth allocated by the OLT.

The plurality of optical network units may include multiple different types of optical network units, for example, in a specific embodiment, it may include a traditional EPON optical network unit (that is, a traditional EPON ONU) whose uplink and downlink data rates are 1G 10G symmetric 10G EPON optical network unit (symmetrical 10G EPON ONU) with uplink and downlink data rates of 10G and asymmetric 10G EPON optical network unit (asymmetric 10G EPON ONU) with uplink and downlink data rates of 1G and 10G respectively ONU). For the convenience of description, the optical network unit with an uplink data rate of 1G (including asymmetric 10G EPON ONU and traditional EPON ONU) is collectively referred to as 1G ONU, and the uplink optical signal with a data rate of 1G sent by it is called It is a 1G uplink signal; and the optical network unit (symmetric 10G EPON ONU) whose uplink data is 10G is called a 10G ONU, and the uplink optical signal with a data rate of 10G sent by it is called a 10G uplink signal. Wherein, the 1G ONU may use a distributed Fabry-Perot (Fabry Perot, FP) laser to send the 1G uplink signal, and the wavelength range of the 1G uplink signal may be 1260nm～1360nm, and the center wavelength is 1310nm; The 10G ONU can use a distributed feedback (Distributed Feedback, DFB) laser to send the 10G uplink signal, and the wavelength range of the 10G uplink signal can be 1260nm～1280nm, and the center wavelength is 1270nm.

The embodiment of the present invention provides a method for allocating uplink bandwidth of a 10G EPON system, as shown in Figure 2, the method may include:

Step 101, the optical line terminal judges whether the upstream wavelengths of the 1G ONU and the 10G ONU overlap;

Step 102, if the upstream wavelengths do not overlap, the optical line terminal allocates wavelength division multiplexing bandwidth for the 1G ONU and the 10G ONU, so that the upstream signals are transmitted between the 1G ONU and the 10G ONU in a wavelength division multiplexing manner.

Step 103, if the upstream wavelengths overlap, the optical line terminal allocates time-division multiplexing bandwidth for the 1G ONU and the 10G ONU, so that the upstream signals are sent between the 1G ONU and the 10G ONU in a time-division multiplexing manner.

In a specific embodiment, before performing the above-mentioned uplink bandwidth allocation method, the optical line terminal at the central office can pre-identify the characteristics of all optical network units remotely connected to the optical line terminal in the 10G EPON system, such as Perform wavelength feature identification or rate feature identification to determine the type of the optical network unit remotely connected to the optical line terminal.

If it is judged through the above feature identification that the optical network unit connected to the optical line terminal at the remote end has only 1G ONU or only 10G ONU, in order to avoid wavelength conflicts between multiple 1G ONUs or between multiple 10G ONUs, the The optical line terminal at the central office may determine to only allocate time-division multiplexing bandwidth to the remote optical network unit, so that the multiple 1G ONUs or the multiple 10G ONUs respectively send 1G uplink signals or 10G uplink signal.

If it is judged through the above feature identification that the optical network unit connected to the optical line terminal at the remote end includes both 1G ONU and 10G ONU, then the optical line terminal at the central office can perform the above step 101, that is, determine that the 1G ONU Whether it overlaps with the upstream wavelength of the 10G ONU.

Specifically, the judgment about whether wavelength overlap occurs in the above step 101 may be that all 1G ONUs and 10G ONUs connected to the optical line terminal are judged one by one, and the results are recorded.

Please refer to Fig. 3, which is a schematic diagram of judging whether wavelength overlap occurs according to an embodiment of the present invention. G1-Gm in Fig. 3 represent m 10G ONUs of the 10G EPON system respectively, and T1-Tn represent the 10G EPON system respectively n 1G ONUs. Specifically, one of the 10G ONUs is first selected, and the wavelength overlap judgment between the 10G ONU and a 1G ONU is performed, and the judgment result is recorded; then, the wavelength overlap judgment is performed between the 10G ONU and the next 1G ONU, and the judgment is recorded As a result, by analogy, until the 10G ONU and all 1G ONUs perform wavelength overlap judgment one by one. Afterwards, reselect another 10G ONU and make wavelength overlap judgments with all 1G ONUs one by one and record the judgment results; finally, you can make wavelength overlap judgments between all 1G ONUs and all 10G ONUs Therefore, the optical line terminal at the central office also records the wavelength overlapping judgment information of all optical network units.

Optionally, please refer to Figure 3. In the above-mentioned judgment process about whether wavelength overlap occurs, the wavelength overlap judgment process between one 1G ONU and one 10G ONU can be as follows:

First, the optical line terminal at the central office allocates the same bandwidth for the 1G ONU and the 10G ONU, so that the 1G ONU and the 10G ONU simultaneously send uplink signals to the optical line terminal within the same time window, and the The 1G uplink signal and the 10G uplink signal sent by the 1G ONU and the 10G ONU are transmitted to the optical line terminal through the optical distribution network;

Secondly, the optical line terminal judges whether it can correctly receive the upstream signals from the 1G ONU and the 10G ONU within the time window, that is, the 1G upstream signal and the 10G upstream signal; if the optical line terminal Judging that the 1G uplink signal sent by the 1G ONU and the 10G uplink signal sent by the 10G ONU can be correctly received, it can confirm that the wavelengths between the uplink signals of the 1G ONU and the 10G ONU do not overlap; If it cannot be received correctly, the optical line terminal can confirm the wavelength overlap between the upstream signals of the 1G ONU and the 10G ONU.

The specific principle of the above judgment process is: assuming that the wavelengths of the 1G uplink signal and the 10G uplink signal from the remote optical network unit overlap within the same time window, then the 1G uplink signal and the 10G uplink signal within the time window overlap. The 10G uplink signals will interfere with each other, so that the optical line terminal cannot correctly identify and resolve the 1G uplink signal and the 10G uplink signal from the signals received within the time window. Therefore, the The optical line terminal can judge that the upstream wavelengths of the 1G ONU and the 10G ONU overlap at this time. Conversely, if the upstream wavelengths of the two do not overlap, the 1G upstream signal and the 10G upstream signal sent by the 1G ONU and the 10G ONU to the optical line terminal within the same time window will not interfere with each other, then The optical line terminal can correctly identify and analyze both the 1G uplink signal and the 10G uplink signal, so it can be judged that the uplink wavelengths of the two do not overlap.

Specifically, in order to realize the above-mentioned judgment about whether wavelength overlap occurs between the 1G ONU and the 10G ONU, the optical module of the optical line terminal can be configured with a 1G uplink receiving path and a 10G uplink receiving path, and the two are respectively used to receive 1G The uplink signal and the 10G uplink signal, and the preset allowable receiving wavelength ranges of the two correspond to the wavelength ranges of the above-mentioned 1G uplink signal and the 10G uplink signal respectively. In a specific embodiment, by separately configuring the allowable receiving wavelength ranges, the 1G uplink signal and the 10G uplink signal from the remote optical network unit can be respectively received by the The data received by the 1G uplink receiving path and the 10G uplink receiving path are sent to a data processing module, such as a Media Access Control (MAC) module for parsing and processing.

After judging whether wavelength overlap occurs between the 1G ONU and the 10G ONU through the above step 101 and recording the judging result, the optical line terminal can perform the bandwidth allocation in step 102 and step 103 according to the judging result, for the uplink For 1G ONUs and 10G ONUs with non-overlapping wavelengths, the optical line terminal can allocate wavelength division multiplexing bandwidth to them, so that they can send uplink signals in the way of wavelength division multiplexing, while for 1G ONUs and 10G ONUs whose uplink wavelengths overlap ONU, the optical line terminal can allocate time-division multiplexing bandwidth to it, so that it can send uplink signals in a time-division multiplexing manner. Through the bandwidth allocation method described above, the embodiment of the present invention can make full use of the high bandwidth of the 10G uplink by using the wavelength division multiplexing method, greatly improving the uplink transmission capacity of the 10G EPON system, thereby improving the utilization rate of the uplink bandwidth.

In this embodiment, after the optical line terminal allocates wavelength division multiplexing bandwidth or time division multiplexing bandwidth to the 1GONU and 10G ONU in the 10G EPON system according to the wavelength overlap judgment result, the remote 1G ONU and 10G ONU According to the bandwidth allocated by the optical line terminal, the 1G uplink signal and the 10G uplink signal can be respectively sent to the optical line terminal by using time division multiplexing or wavelength division multiplexing, so that the optical line terminal can receive all The uplink signals sent by the 1G ONU and the 10GONU are processed.

Please refer to FIG. 4 , which is a schematic structural diagram of an optical module of an optical line terminal provided by an embodiment of the present invention. The optical module may include: an optical splitter 201, a first uplink receiving path 202, and a second uplink receiving path 203; wherein, the first uplink receiving path 202 may include a photodiode 2021, a transimpedance amplifier 2022, and a low-pass filter connected in sequence. 2023 and limiting amplifier 2024; the second uplink receiving path 202 may include a filter 2031, a photodiode 2032, a transimpedance amplifier 2033 and a limiting amplifier 2034 connected in sequence.

In this embodiment, the first uplink receiving path 202 may be a 1G uplink signal receiving path, which is used to receive a 1G uplink signal sent from a remote 1G ONU, and the first uplink receiving path 202 is configured with a low The pass filter 2023 is used to filter out the 10G uplink signal sent from the far-end 10G ONU.

The second uplink receiving path 203 may be a 10G uplink signal receiving path, which is used to receive a 10G uplink signal sent from a remote 10GONU, and the filter 2031 configured in the first uplink receiving path 202 is used to make the wavelength range The uplink signal with a wavelength range of 1260 to 1280nm is passed, while the uplink signal with a wavelength range of 1280 to 1360nm is filtered out.

In this embodiment, on the one hand, when the wavelengths of the remote 1G ONU and the 10G ONU overlap, the 1G ONU and the 10G ONU pass the wavelength division multiplexing bandwidth allocated by the optical line terminal through the wavelength division multiplexing bandwidth. The 1G uplink signal and the 10G uplink signal are sent to the optical line terminal in a multiplexing manner, and the optical line terminal can receive the 1G uplink signal and the 10G uplink signal sent by the 1G ONU and the 10G ONU through the optical module.

Specifically, the optical splitter 201 can divide the uplink signal (including the 1G uplink signal sent by the 1G ONU and the 10G uplink signal sent by the 10G ONU) into two paths, namely the first uplink signal and the second uplink signal, and transmit them to The first uplink receiving path 202 and the second uplink receiving path 203 . Wherein, each uplink signal is a mixed wavelength signal, which includes two wavelengths respectively corresponding to the 1G uplink signal and the 10G uplink signal.

In the second uplink receiving path 203, since the wavelength of the 1G uplink signal sent by the 1G ONU does not overlap with the wavelength of the 10G uplink signal sent by the 10G ONU, when the second uplink signal passes through the filter 2031, the The 1G uplink signal sent by the 1G ONU will be filtered out by the filter 2031, so only the 10G uplink signal sent by the 10G ONU can pass through the filter 2031 and be correctly received by the second uplink receiving path 203.

In the first uplink receiving channel 202, the two kinds of uplink signals contained in the second uplink signal (i.e., 1G uplink signal and 10G uplink signal) can be photoelectrically converted through the photodiode 2021, and then through the transimpedance amplifier 2022. After the pre-amplification, the 10G uplink signal sent by the 10G ONU is filtered out by the low-pass filter 2023, and only the 1G uplink signal sent by the 1G ONU passes through, so that the first uplink receiving path 202 can realize all Correct reception of the 1G uplink signal sent by the above 1G ONU.

In this embodiment, on the other hand, when the wavelengths of the remote 1G ONU and the 10G ONU overlap, the 1G ONU and the 10G ONU use time-division multiplexing according to the time-division multiplexing bandwidth allocated by the optical line terminal. When sending the 1G uplink signal and the 10G uplink signal to the optical line terminal by means, the optical line terminal can also receive the 1G uplink signal and the 10G uplink signal sent by the 1G ONU and the 10G ONU through the optical module.

Specifically, when the uplink signal received by the optical line terminal in a certain time slot is the 10G uplink signal sent by the 10G ONU, the optical splitter 201 can divide the 10G uplink signal into two paths and send them to the first An uplink receiving path 202 and the second uplink receiving path 203 . Since the first uplink receiving path 202 is provided with the low-pass filter 2023, which can filter out the 10G uplink signal entering the first uplink receiving path 202, only the 10G uplink signal entering the second uplink receiving path The 10G uplink signal of 203 can be received by the optical module of the optical line terminal, and the optical module can further transmit the 10G uplink signal received by the second uplink receiving channel 203 to the MAC module for processing. In fact, since the optical line terminal allocates time-division multiplexing bandwidth to the 10G ONU, the MAC module of the optical line terminal itself also knows that the uplink signal received in this time slot is only a 10G uplink signal, so The MAC module will only extract the uplink signal received by the second uplink receiving channel 203 .

When the uplink signal received by the optical line terminal in a certain time slot is the 1G uplink signal sent by the 1G ONU, the optical splitter 201 will also divide the 1G uplink signal into two paths and send them to the first uplink signal respectively. receiving path 202 and the second uplink receiving path 203 . Since the optical line terminal allocates time-division multiplexing bandwidth for the 1G ONU, the MAC module of the optical line terminal itself knows that the uplink signal received in this time slot is only a 1G uplink signal, so the MAC module Only the uplink signal received by the first uplink receiving channel 202 will be extracted.

It can be seen that, through the optical module structure shown in Figure 4, regardless of whether the 1G uplink signal and the 10G uplink signal sent by the 1G ONU and the 10G ONU are transmitted to the optical line terminal by time division multiplexing, or by wave The optical line terminal can correctly receive the 1G uplink signal and the 10G uplink signal sent by the 1G ONU and the 10G ONU.

It should be understood that in the 10G EPON system, since the remote optical network unit includes multiple 1G ONUs and multiple 10G ONUs, the optical module may receive both the 1G uplink signal and the 10G uplink signal, it is also possible to receive 1G uplink signal and 10G uplink signal transmitted by wavelength division multiplexing. FIG. 5 is a schematic transmission diagram of an uplink signal transmitted in a time division multiplexing manner and a wavelength division multiplexing manner according to an embodiment of the present invention. As shown in Figure 5, at the same time, the optical line terminal may only receive 1G uplink signals or 10G uplink signals (that is, the 1G uplink signals and 10G uplink signals are transmitted in a time-division multiplexed manner), and may also receive 1G uplink signal and 10G uplink signal (that is, the 1G uplink signal and 10G uplink signal are transmitted by wavelength division multiplexing)

Further, in order to further improve the efficiency of transmission, in the embodiment of the present invention, after completing the wavelength overlap judgment about the 1G ONU and the 10GONU, the optical line terminal can identify the 1G ONU that does not overlap with the wavelength of the 10G ONU, For example, it can be tagged (TAG). And, when the optical line terminal allocates the upstream bandwidth for the marked 1G ONU, it can allocate the same bandwidth for the 10G ONU that does not overlap with the wavelength of the 1G ONU, so that the two can send upstream signals through wavelength division multiplexing.

For example, assuming that A is a 1G ONU and B is a 10G ONU, and the wavelengths of A and B do not overlap, the optical line terminal can identify A. According to the identification, the optical line terminal can preferentially allocate bandwidth to the 1G ONU, and if at time T, the optical line terminal allocates bandwidth to A, the optical line terminal can also allocate the same bandwidth to B, A and B transmit uplink signals in a wavelength division multiplexing manner.

Fig. 6 is a schematic diagram of transmission of uplink signals after identification is adopted. As shown in Figure 6, the transmission of the upstream signal of the 1G ONU can be guaranteed first, and the upstream signal of the identified 1G ONU (1G upstream ') can be wavelength division multiplexed with the upstream signal of the 10G ONU. Therefore, the embodiment of the present invention can further realize the priority scheduling of the optical line terminal at the central office to the optical network unit at the remote end, and improve transmission efficiency.

Based on the uplink wavelength allocation method of the 10G EPON system described in the above embodiments, the embodiment of the present invention also provides an optical line terminal, which can be applied to the 10G EPON system as an uplink bandwidth allocation device of the 10G EPON system, As shown in FIG. 7, the optical line terminal may include: a wavelength judgment unit 501 and a bandwidth allocation unit 502; wherein,

A wavelength judging unit 501, configured to judge whether the uplink wavelengths of the first optical network unit and the second optical network unit with different uplink rates overlap, wherein the first optical network unit and the second optical network unit can be the above-mentioned The 1G ONU and the 10G ONU described in the embodiment can send 1G uplink signals and 10G uplink signals respectively.

The bandwidth allocating unit 502 is configured to allocate uplink bandwidth to the first ONU and the second ONU according to the judgment result of the wavelength judging unit 501 .

In a specific embodiment, when the wavelength judging unit 501 judges that the uplink wavelengths of the first ONU and the second ONU do not overlap, the bandwidth allocation unit 502 may allocate The network unit and the second optical network unit allocate wavelength division multiplexing bandwidth so that the first optical network unit and the second optical network unit use wavelength division multiplexing to send uplink signals; When unit 501 determines that the uplink wavelengths of the first ONU and the second ONU overlap, allocate time-division multiplexing bandwidth to the first ONU and the second ONU so that the The first optical network unit and the second optical network unit transmit uplink signals in a time division multiplexing manner.

Specifically, as shown in FIG. 8, the wavelength judging unit 501 may include: a pre-allocation unit 601, a signal judging unit 602, and a determining unit 603; wherein,

The pre-allocation unit 601 is configured to allocate the same bandwidth to the first ONU and the second ONU, so as to authorize the first ONU and the second ONU to send respectively within the same time window a first uplink signal and a second uplink signal with different data rates;

The signal judging unit 602 is configured to judge that the first uplink signal sent by the first ONU and the second uplink signal sent by the second ONU can be correctly received within the time window;

The determination unit 603 is configured to determine that the uplink wavelengths of the first optical network unit and the second optical network unit do not overlap when the determination result of the signal determination unit 602 is that the signal can be received correctly. When the judgment result is that the reception cannot be performed correctly, it is determined that the uplink wavelengths of the first ONU and the second ONU overlap.

Please refer to FIG. 7 again. In one embodiment, the optical line terminal may further include a receiving optical module 504, which is used to receive the transmission from the first optical network transmitted by wavelength division multiplexing or time division multiplexing. The first uplink signal of the unit and the second uplink signal from the second ONU.

In a specific embodiment, the structure of the receiving light module 504 can be as shown in FIG. 4 , specifically, referring to FIG. 4 , the receiving light module 504 can include: and the second uplink receiving channel 203;

The optical splitter 201 is configured to perform optical splitting processing on the first uplink signal from the first optical network unit and the second uplink signal from the second optical network unit transmitted in a wavelength division multiplexing manner or a time division multiplexing manner, so as to generating a first uplink signal and a second uplink signal, and providing the first uplink signal and the second uplink signal to the first uplink receiving path 202 and the second uplink receiving path 203 respectively and, The first uplink receiving path 202 may correspond to the uplink data rate of the first ONU, and the second uplink receiving path 202 may correspond to the uplink data rate of the second ONU, The first uplink receiving path 202 is used to receive the first uplink signal sent by the first optical network unit and filter the second uplink signal sent by the second optical network unit, and the second uplink receiving path 203 It is used for receiving the second uplink signal sent by the second ONU and filtering the first uplink signal sent by the first ONU.

Wherein, the first uplink receiving channel 202 includes a photodiode 2021, a transimpedance amplifier 2022, a low-pass filter 2023 and a limiting amplifier 2024 connected in sequence, and the low-pass filter 2023 is used for The second uplink signal of the unit;

The first uplink receiving path 203 includes a filter 2031, a photodiode 2032, a transimpedance amplifier 2033 and a limiting amplifier 2034 connected in sequence; the filter 2031 is used to allow the upstream wavelength range of the second optical network unit The corresponding optical signals are passed, while the optical signals of other wavelength ranges are filtered out, for example, the optical signals with a wavelength range of 1260 to 1280 nm are passed, while the optical signals with a wavelength range of 1280 to 1360 nm are filtered out.

For the specific working process of the above-mentioned receiving light module 504, reference may be made to the description of the above-mentioned embodiments, which will not be described in detail below.

Moreover, in an embodiment, as shown in FIG. 7, the OLT may further include: an identification unit 505, configured to identify the first ONU whose uplink wavelength does not overlap with the second ONU identification; and, when the bandwidth allocation unit 502 allocates the upstream bandwidth to the identified first optical network unit, allocates the same bandwidth to the second optical network unit that does not overlap with the upstream wavelength of the first optical network unit, to authorize the first ONU and the second ONU to send uplink signals at the same time.

The components of the device in this embodiment are respectively used to implement the steps of the method in the preceding embodiments. Since each step has been described in detail in the method embodiment, details will not be repeated here.

Those of ordinary skill in the art can further appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented by electronic hardware, computer software, or a combination of the two. In order to clearly illustrate the hardware and Interchangeability of software. In the above description, the components and steps of each example have been generally described according to their functions. Whether these functions are executed by hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art may use different methods to implement the described functions for each specific application, but such implementation should not be regarded as exceeding the scope of the present invention.

The steps of the methods or algorithms described in connection with the embodiments disclosed herein may be implemented by hardware, software modules executed by a processor, or a combination of both. Software modules can be placed in random access memory (RAM), internal memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disk, removable disk, CD-ROM, or any other Any other known storage medium.

The specific embodiments described above have further described the purpose, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above descriptions are only specific embodiments of the present invention and are not intended to limit the scope of the present invention. Protection scope, within the spirit and principles of the present invention, any modification, equivalent replacement, improvement, etc., shall be included in the protection scope of the present invention.

Claims (14)

1. A method for uplink bandwidth allocation for a 10G EPON, the method comprising:

judging whether the uplink wavelengths of a first optical network unit and a second optical network unit with different uplink data rates are overlapped;

allocating uplink bandwidths for the first optical network unit and the second optical network unit according to the judgment result;

if the uplink wavelengths of the first optical network unit and the second optical network unit are not overlapped, allocating wavelength division multiplexing bandwidths to the first optical network unit and the second optical network unit so as to enable the first optical network unit and the second optical network unit to transmit uplink signals in a wavelength division multiplexing mode; if the uplink wavelengths of the first optical network unit and the second optical network unit are overlapped, allocating time division multiplexing bandwidths to the first optical network unit and the second optical network unit so as to enable the first optical network unit and the second optical network unit to transmit uplink signals in a time division multiplexing mode.

2. The method of claim 1, wherein the determining whether the uplink wavelengths of the first optical network unit and the second optical network unit with different uplink data rates overlap comprises:

allocating the same bandwidth to the first optical network unit and the second optical network unit to authorize the first optical network unit and the second optical network unit to respectively send a first uplink signal and a second uplink signal within the same time window, wherein the data rates of the first uplink signal and the second uplink signal are different;

judging whether a first uplink signal sent by the first optical network unit and a second uplink signal sent by the second optical network unit can be correctly received in the time window;

if the uplink wavelength of the first optical network unit is not overlapped with the uplink wavelength of the second optical network unit, judging that the uplink wavelengths of the first optical network unit and the second optical network unit are not overlapped; otherwise, judging that the uplink wavelengths of the first optical network unit and the second optical network unit are overlapped.

3. The method of claim 1, wherein after allocating wavelength division multiplexing bandwidth for the first optical network unit and the second optical network unit, the method further comprises:

performing optical splitting processing on a first uplink signal from the first optical network unit and a second uplink signal from the second optical network unit, which are transmitted in a wavelength division multiplexing manner, by using an optical splitter to generate a first path of uplink signal and a second path of uplink signal, wherein each path of uplink signal is a mixed wavelength signal including the first uplink signal and the second uplink signal;

receiving the first path of uplink signal by using a first uplink receiving path corresponding to the uplink data rate of the first optical network unit, filtering a second uplink signal in the first path of uplink signal to obtain a first uplink signal sent by the first optical network unit, and providing the obtained first uplink signal to a data processing module for data processing;

and receiving the second path of uplink signals by using a second uplink receiving path corresponding to the uplink data rate of the second optical network unit, filtering the first uplink signals to obtain second uplink signals sent by the second optical network unit, and providing the obtained second uplink signals to a data processing module for data processing.

4. The method of claim 1, wherein after allocating wavelength division multiplexing bandwidth for the first optical network unit and the second optical network unit, the method further comprises:

performing, by using an optical splitter, optical splitting processing on a first uplink signal from the first optical network unit and a second uplink signal from the second optical network unit, which are transmitted in a time division multiplexing manner, to generate a first uplink signal and a second uplink signal, where each uplink signal carries the first uplink signal and the second uplink signal in a first time slot and a second time slot, respectively;

receiving the first path of uplink signal by using a first uplink receiving path corresponding to the uplink data rate of the first optical network unit in the first time slot, and providing the first uplink signal carried by the first path of uplink signal to a data processing module for data processing;

and receiving the second path of uplink signals by using a second uplink receiving path corresponding to the uplink data rate of the second optical network unit in the second time slot, and providing the second uplink signals carried by the second path of uplink signals to the data processing module for data processing.

5. The method of claim 1, further comprising: identifying a first optical network unit which is not overlapped with the uplink wavelength of the second optical network unit;

and when the identified first optical network unit is allocated with the uplink bandwidth, allocating the same bandwidth for a second optical network unit which is not overlapped with the uplink wavelength of the first optical network unit so as to authorize the first optical network unit and the second optical network unit to send uplink signals at the same time.

6. An optical line terminal, comprising:

the wavelength judging unit is used for judging whether the uplink wavelengths of the first optical network unit and the second optical network unit with different uplink rates are overlapped;

a bandwidth allocation unit, configured to allocate uplink bandwidths to the first optical network unit and the second optical network unit according to a determination result of the wavelength determination unit;

when the wavelength judging unit judges that the uplink wavelengths of the first optical network unit and the second optical network unit are not overlapped, the bandwidth allocating unit allocates wavelength division multiplexing bandwidths to the first optical network unit and the second optical network unit so as to enable the first optical network unit and the second optical network unit to transmit uplink signals in a wavelength division multiplexing mode; when the wavelength judging unit judges that the uplink wavelengths of the first optical network unit and the second optical network unit are overlapped, allocating time division multiplexing bandwidths to the first optical network unit and the second optical network unit so as to enable the first optical network unit and the second optical network unit to transmit uplink signals in a time division multiplexing mode.

7. The olt of claim 6, wherein the wavelength determination unit comprises:

the pre-allocation unit is used for allocating the same bandwidth to the first optical network unit and the second optical network unit so as to authorize the first optical network unit and the second optical network unit to respectively send a first uplink signal and a second uplink signal with different data rates in the same time window;

a signal determining unit, configured to determine that a first uplink signal sent by the first optical network unit and a second uplink signal sent by the second optical network unit can be correctly received within the time window;

a determining unit, configured to determine that the uplink wavelengths of the first optical network unit and the second optical network unit do not overlap when the determination result of the signal determining unit is that correct reception is possible, and determine that the uplink wavelengths of the first optical network unit and the second optical network unit overlap when the determination result of the signal determining unit is that correct reception is not possible.

8. The olt of claim 6, further comprising: a receiving optical module, configured to receive a first uplink signal from the first optical network unit and a second uplink signal from a second optical network unit, which are transmitted in a wavelength division multiplexing manner or a time division multiplexing manner;

the receiving optical module includes a first uplink receiving path corresponding to an uplink data rate of the first optical network unit and a second uplink receiving path corresponding to an uplink data rate of the second optical network unit, where the first uplink receiving path is used to receive a first uplink signal sent by the first optical network unit and filter a second uplink signal sent by the second optical network unit, and the second uplink receiving path is used to receive a second uplink signal sent by the second optical network unit and filter a first uplink signal sent by the first optical network unit.

9. The olt of claim 8, wherein the optical receiving module further includes an optical splitter, and is configured to perform optical splitting on a first uplink signal from the first onu and a second uplink signal from the second onu that are transmitted in a wavelength division multiplexing manner or a time division multiplexing manner to generate a first uplink signal and a second uplink signal, and provide the first uplink signal and the second uplink signal to the first uplink receiving path and the second uplink receiving path, respectively.

10. The olt of claim 9, wherein the first upstream receiving path comprises a photodiode, a transimpedance amplifier, a low-pass filter, and a limiting amplifier, which are connected in sequence, wherein the low-pass filter is configured to filter a second upstream signal from the second onu;

the second uplink receiving path comprises a filter, a photodiode, a transimpedance amplifier and a limiting amplifier which are connected in sequence; the filter is used for allowing the optical signals consistent with the upstream wavelength range of the second optical network unit to pass through, and filtering the optical signals in other wavelength ranges.

11. The olt of claim 6, further comprising:

the identification unit is used for identifying the first optical network unit which is not overlapped with the uplink wavelength of the second optical network unit;

and when the bandwidth allocation unit allocates the uplink bandwidth for the first optical network unit after identification, the same bandwidth is allocated for a second optical network unit which is not overlapped with the uplink wavelength of the first optical network unit, so as to authorize the first optical network unit and the second optical network unit to send uplink signals at the same time.

12. An optical access system, comprising a central office device and a plurality of remote devices, wherein the central office device is coupled to the plurality of remote devices in a point-to-multipoint manner;

the plurality of remote devices include a first remote device and a second remote device with different uplink data rates, and the first remote device and the second remote device are respectively used for sending a first uplink signal and a second uplink signal to the central office device;

the local device is configured to determine whether uplink wavelengths of the first remote device and the second remote device overlap, allocate a wavelength division multiplexing bandwidth to the first remote device and the second remote device when the uplink wavelengths do not overlap, so that the first uplink signal and the second uplink signal are sent between the first remote device and the second remote device in a wavelength division multiplexing manner, and allocate a time division multiplexing bandwidth to the first remote device and the second remote device when the uplink wavelengths overlap, so that the first uplink signal and the second uplink signal are sent between the first remote device and the second remote device in a time division multiplexing manner.

13. The optical access system of claim 12, wherein the remote device is an optical network unit, the first remote device includes an EPON optical network unit having uplink and downlink data rates of 1G and an asymmetric 10G EPON optical network unit having uplink and downlink data rates of 1G and 10G, respectively, and the second remote device includes a symmetric 10G EPON optical network unit having uplink and downlink data rates of 10G.

14. The optical access system according to claim 12, wherein the local-side device is an optical line terminal according to any one of claims 6 to 11.

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