WO2013097183A1

WO2013097183A1 - Method, device and system for initialising wavelength of adjustable laser

Info

Publication number: WO2013097183A1
Application number: PCT/CN2011/085041
Authority: WO
Inventors: 钱银博; 刘爽; 黄晶; 付生猛; 周小平; 彭桂开
Original assignee: 华为技术有限公司
Priority date: 2011-12-30
Filing date: 2011-12-30
Publication date: 2013-07-04
Also published as: CN102725669A; CN102725669B

Abstract

Disclosed are a method, a device and a system for initialising the wavelength of an adjustable laser. The system comprises: a process (12), a memory (13) and a bidirectional optical sub-assembly according to the present invention. The process (12) is connected respectively to an adjustable laser (14) and an adjustable receiver (17) in the bidirectional optical sub-assembly, for receiving the signal power of an uplink signal obtained by the adjustable receiver (17), which uplink signal is the uplink signal within a first wavelength range of the adjustable laser; for obtaining a maximal signal power, the uplink signal corresponding thereto being the uplink signal corresponding to the target initialising wavelength for the adjustable laser (14); for obtaining parameters for the adjustable laser corresponding to the maximal signal power; and for controlling the adjustable laser (14) to transmit the uplink signal corresponding to the target initialising wavelength according to the parameters for the adjustable laser. The present invention simplifies the initialising process and reduces costs for initialisation.

Description

Tunable laser wavelength initialization method, device and system

Technical field

The present invention relates to optical network technologies, and more particularly to a tunable laser wavelength initialization method, apparatus and system. Background technique

A Passive Optical Network (PON) system is a point-to-multipoint optical network in which an Optical Line Terminal (OLT) passes through an optical splitter and multiple client terminals. The Network Unit (Optical Network Unit, ONU) is connected. With the development of optical communication technology, the OLT and ONU gradually adopt the method of wavelength division transmission to transmit data. For example, different ONUs use different wavelengths of optical signals to transmit data. In a specific implementation, a transmitter for transmitting an optical signal may be loaded on each ONU, and wavelengths emitted by transmitters of different ONUs are different, and optical signals of different wavelengths are collectively transmitted to the OLT to implement wavelength division. Reuse. However, this situation requires device manufacturers to make a large number of transmitters of different wavelengths and load them separately to different ONUs at a higher cost. In order to reduce the cost, there is a tunable transmitter that can adjust different wavelengths in a certain wavelength range, so that the tunable transmitter can be loaded on different ONUs, and each ONU only needs to be adjustable. The transmitter can be adjusted to its own wavelength, so that the ONU can be mass-produced and the cost can be reduced.

However, to achieve the above application of the tunable transmitter to the ONU, the following problems exist: The tunable transmitter includes a tunable laser for transmitting an optical signal, and the ONU needs to perform before using the tunable transmitter to transmit an uplink signal. The wavelength is initialized, that is, the laser is adjusted to the wavelength corresponding to the ONU. The prior art is to complete ONU wavelength initialization by an Array Waveguide Grating (AWG) filter and an OLT; the AWG is a filter with multiple wavelength channels, only when the tunable laser emits an optical signal. When the wavelength is consistent with the wavelength of a certain channel, the optical signal can pass; and, the PON system sets a different signal sequence for each ONU at the protocol layer, so that the OLT recognizes different ONUs; only when the OLT is in the correct channel of the AWG The correct signal sequence is received, thereby confirming that the current wavelength is the correct ONU corresponding wavelength, and sending an acknowledgment signal to the ONU to complete the initialization of the ONU wavelength. However, the above wavelength initialization method requires In addition to the ONU, the cooperation between the AWG and the OLT is increased, and the protocol layer needs to be modified, the modification is large, the initialization method is complicated, and the cost is high. SUMMARY OF THE INVENTION A first aspect of the present invention provides a wavelength division multiplexer for the purpose of changing an optical path of an uplink signal transmitted by a tunable laser by the wavelength division multiplexer such that a portion of the uplink signal enters the tunable receiver.

Another aspect of the present invention provides a fiber optic bidirectional assembly for acquiring a partial uplink signal transmitted by a tunable laser in a fiber bidirectional component into a tunable receiver, and capable of performing the obtained partial uplink signal Filtering.

Yet another aspect of the present invention is to provide a tunable laser wavelength initialization system for the purpose of simplifying the wavelength initialization process and reducing the initialization cost.

Still another aspect of the present invention is to provide an optical network device for the purpose of simplifying the wavelength initialization process and reducing the initialization cost.

It is still another aspect of the present invention to provide a tunable laser wavelength initialization method for the purpose of simplifying the wavelength initialization process and reducing the initialization cost.

The wavelength division multiplexer provided by the present invention comprises: a sidewall and an inner cavity surrounded by the sidewall; a first reflective layer disposed in a cavity of the wavelength division multiplexer for transmitting an uplink signal The tunable laser is oppositely disposed at an angle of 45 degrees with the emission direction of the uplink signal, and is used for reflecting part of the uplink signal;

a second reflective layer disposed on a sidewall of the wavelength division multiplexer opposite to the first reflective layer and disposed perpendicular to an emission direction of the uplink signal reflected by the first reflective layer for use in reflecting The subsequent uplink signal is again reflected at a reflectivity of 100%, such that the upstream signal passes through the first reflective layer and enters the tunable receiver from the wavelength division multiplexer for the wavelength of the tunable laser initialization.

The optical fiber bidirectional component provided by the present invention includes: a wavelength division multiplexer; the optical fiber bidirectional component further includes: a tunable transmitter and a tunable receiver, wherein the tunable transmitter includes an audible transmitter Tuning a laser, the tunable receiver comprising a tunable filter and a receiver;

The tunable laser is configured to transmit an uplink signal to the wavelength division multiplexer; the wavelength range of the uplink signal emitted by the tunable laser is a first wavelength range;

The wavelength division multiplexer is configured to reflect a part of the uplink signal emitted by the tunable laser into the The tunable filter;

The tunable filter is configured to receive the uplink signal reflected by the wavelength division multiplexer, and transmit the uplink signal to the receiver; The tunable laser initializes the target wavelength such that an uplink signal corresponding to the initialization target wavelength passes at a maximum signal power in the first wavelength range; the tunable wavelength range of the tunable filter is a second wavelength range The second wavelength range includes the first wavelength range;

The receiver is configured to acquire signal power of an uplink signal received by the tunable filter. The tunable laser wavelength initialization system provided by the present invention comprises: a processor, a memory, and the optical fiber bidirectional component of the present invention;

The processor is respectively connected to the tunable laser and the tunable receiver in the optical fiber bidirectional component, and is configured to receive signal power of an uplink signal obtained by the tunable receiver, where the uplink signal is the adjustable An uplink signal in a first wavelength range of the laser; and, configured to obtain a maximum signal power, where the uplink signal corresponding to the maximum signal power is an uplink signal corresponding to an initializing target wavelength of the tunable laser, and acquiring the maximum signal a tunable laser parameter corresponding to the power; and, configured to, according to the tunable laser parameter, control the tunable laser to transmit an uplink signal corresponding to the initialization target wavelength.

The optical network device provided by the present invention comprises the tunable laser wavelength initialization system of the present invention. The method for initializing a wavelength of an optical network device provided by the present invention, the optical network device includes: a tunable laser, a wavelength division multiplexer, a tunable receiver, and a processor, wherein the wavelength division multiplexer and the adjustable The laser is coupled to the tunable receiver, the tunable receiver includes a tunable filter and a receiver, the processor being respectively coupled to the receiver and the tunable laser; the wavelength initialization method includes: setting an adjustable filter The receiving wavelength of the device is the initializing target wavelength of the tunable laser;

The processor controls the tunable laser to emit an uplink signal in a first wavelength range;

The wavelength division multiplexer reflects the uplink signal transmitted by the tunable laser, so that part of the uplink signal enters the tunable receiver;

The tunable receiver acquires signal power of the uplink signal and transmits the signal power to the processor;

The processor detects the signal power of the uplink signal in the first wavelength range, and obtains the maximum signal power, where the uplink signal corresponding to the maximum signal power is an uplink signal corresponding to the initializing target wavelength of the tunable laser, and acquires The tunable laser parameter corresponding to the maximum signal power, Controlling, by the tunable laser parameter, the uplink signal corresponding to the initialization target wavelength according to the tunable laser parameter.

The technical effect of the wavelength division multiplexer of the present invention is: by providing a first reflective layer and a second reflective layer in the wavelength division multiplexer, the uplink signals transmitted by the initial tunable laser can be performed through the two reflective layers. Continuous reflection, which ultimately changes the optical path of the upstream signal. The structure of the wavelength division multiplexer enables it to reflect part of the upstream signal into the tunable receiver for wavelength initialization of the tunable laser when applied to wavelength initialization. The initialization scheme plays a role in assisting to change the optical path. Compared with the prior art, since the wavelength division multiplexer reflects the uplink signal into the tunable receiver for wavelength initialization of the tunable laser, it is no longer necessary to add additional The combination of the AWG and the OLT simplifies the wavelength initialization process and reduces the initialization cost.

The technical effect of the optical fiber bidirectional component of the present invention is: by using the wavelength division multiplexer of the present invention in the optical fiber bidirectional component, the wavelength division multiplexer can reflect a part of the uplink signal transmitted by the tunable laser into the tunable filter. And; by setting the tunable filter, and setting the receiving wavelength of the tunable filter to the initializing target wavelength of the tunable laser, it can play an auxiliary filtering role in the initialization scheme, only the same uplink as the initializing target wavelength The signal can enter the receiver through the tunable filter with a larger power; compared to the prior art, since the fiber bidirectional component acquires a partially reflected signal into the tunable receiver for wavelength initialization of the tunable laser, there is no need to increase The combination of additional AWG and OLT simplifies the wavelength initialization process and reduces initialization costs.

The technical effect of the tunable laser wavelength initialization system of the present invention is: detecting, by the processor, the signal power of the uplink signal received by the tunable receiver, wherein the uplink signal is an uplink signal in a first wavelength range of the tunable laser, Obtaining an uplink signal corresponding to the maximum signal power in the first wavelength range is an uplink signal corresponding to the initialization target wavelength, and the processor can control the tunable laser to transmit an uplink signal having the initialization target wavelength, thereby achieving The wavelength of the laser is initialized. Compared with the prior art, the method is completed by a functional unit in the access network device itself, such as a tunable laser and a tunable receiver. It is no longer necessary to add additional AWG and OLT cooperation. The wavelength initialization process is simplified and the initialization cost is reduced.

The technical effect of the optical network device of the present invention is: detecting, by a processor, a signal power of an uplink signal received by the tunable receiver, wherein the uplink signal is an uplink signal in a first wavelength range of the tunable laser, and obtaining the The upstream signal corresponding to the maximum signal power in a wavelength range is the initial The upstream signal corresponding to the target wavelength is controlled, and the processor can control the tunable laser to emit the uplink signal having the initializing target wavelength, thereby realizing the wavelength initialization of the tunable laser, which is compared with the prior art. The functional units in the access network equipment such as the tuned laser and the tunable receiver are cooperatively completed, and no additional AWG and OLT cooperation is needed, which simplifies the wavelength initialization process and reduces the initialization cost.

The technical effect of the tunable laser wavelength initialization method of the present invention is: detecting, by the processor, the signal power of the uplink signal received by the tunable receiver, wherein the uplink signal is an uplink signal in a first wavelength range of the tunable laser, Obtaining an uplink signal corresponding to the maximum signal power in the first wavelength range is an uplink signal corresponding to the initialization target wavelength, and the processor can control the tunable laser to transmit an uplink signal having the initialization target wavelength, thereby achieving The wavelength of the laser is initialized. Compared with the prior art, the method is completed by a functional unit in the access network device itself, such as a tunable laser and a tunable receiver. It is no longer necessary to add additional AWG and OLT cooperation. The wavelength initialization process is simplified and the initialization cost is reduced. DRAWINGS

1 is a schematic structural view of an embodiment of a tunable laser wavelength initializing system according to the present invention; FIG. 2 is a schematic structural view of the wavelength division multiplexer of FIG.

3 is a schematic structural view of another embodiment of a tunable laser wavelength initialization system according to the present invention; FIG. 4 is a circuit schematic diagram of another embodiment of a tunable laser wavelength initialization system according to the present invention; Schematic diagram of the process of the method embodiment. detailed description

Embodiment 1

1 is a schematic structural diagram of an embodiment of a tunable laser wavelength initialization system according to the present invention. As shown in FIG. 1, the tunable laser wavelength initialization system includes: a bidirectional optical subassembly (abbreviation: BOSA) 11. Processor 12 And memory 13.

The optical fiber bidirectional component 11 includes: a tunable transmitter, the tunable transmitter includes a tunable laser 14 for transmitting an uplink signal, and the uplink signal refers to a signal sent from the tunable laser 14, such as an ONU. The optical signal transmitted to the OLT; further includes a splitter 15, a Wavelength Division Multiplexing (WDM) 16 and a tunable receiver 17. The tunable receiver 17 includes a tunable filter 18 and a receiver 19. The processor 12 is coupled to a tunable laser 14 and a tunable receiver 17 in the fiber optic bi-directional component 11, respectively, and the memory 13 is coupled to the processor 12.

In this embodiment, with respect to the prior art, on the one hand, the structure of the wavelength division multiplexer 16 is improved, so that the wavelength division multiplexer 16 can change the optical path of the uplink signal transmitted by the tunable laser 14, and part of The upstream signal is reflected into the tunable receiver 17; on the other hand, a tunable filter 18 is provided in the tunable receiver 17, and the receiving wavelength of the tunable filter 18 can be set to the initializing target of the tunable laser 14. Wavelength, the effect of this is that the upstream signal of the same wavelength as the initialization target wavelength can pass through the tunable filter 18 with a larger power, so that the uplink signal of the initialization target wavelength can be obtained by power detection; 12: detecting the received signal power, obtaining an uplink signal corresponding to the maximum signal power, the wavelength corresponding to the signal is an initialization target wavelength, and acquiring a laser parameter corresponding to the wavelength, and completing initialization.

The structure and principle of each of the above aspects are specifically described below:

Specifically, FIG. 2 is a schematic structural diagram of the wavelength division multiplexer in FIG. 1. In order to change the optical path of the uplink signal, a part of the uplink signal may enter the tunable receiver, and the embodiment is set in the wavelength division multiplexer. Two reflective layers through which a portion of the upstream signal is reflected to effect optical path changes.

As shown in Fig. 2, the wavelength division multiplexer includes a side wall 21 and a cavity 22 surrounded by the side wall. A first reflective layer 23 is disposed in the inner cavity 22, and the first reflective layer 23 may be a 45-degree glass mirror disposed in the inner cavity 22. As shown in FIG. 1 , the first reflective layer 23 is opposite to the tunable laser 14 and is disposed at an angle of 45 degrees to the emission direction of the uplink signal. The first reflective layer 23 can reflect a portion of the uplink signal, that is, have a certain reflectivity. .

A second reflective layer 24 is disposed on the sidewall 21, and the second reflective layer 24 is disposed perpendicular to the emission direction of the upstream signal reflected by the first reflective layer 23, and the upstream signal can be reflected again. The re-reflected upstream signal will be transmitted vertically downwards and may pass through the first reflective layer 23 and enter the tunable receiver 17 from the wavelength division multiplexer. There is also a small portion of the signal loss as it passes through the first reflective layer 23, but most of the signal will pass down into the tunable receiver 17.

Optionally, in the specific implementation, the first reflective layer 23 and the second reflective layer 24 may be formed in various manners, for example, one or more layers of optical materials of different materials may be plated, or the thickness of the reflective film may be adjusted. The material has a reflective layer with different reflectivity. Optionally, the reflectivity of the first reflective layer 23 of the embodiment may be 5%-15%; the advantage of setting the range is that the sensitivity of different receivers can be satisfied. Specifically, for a typical receiver, the sensitivity is generally lower than -20 dBm. If the sensitivity of 5%--15% is used, the signal power reaching the receiver is generally guaranteed to be higher than -20 dBm, so that The receiver can detect the uplink signal and perform subsequent processing. Moreover, suitable selections can be made within the above range of reflectivity according to different application scenarios. Generally, the higher the reflectivity, the higher the received signal power of the receiver, and the higher the accuracy of the corresponding subsequent detection.

For example, as shown in FIG. 2, the analysis is performed with the reflectance of the first reflective layer 23 being 10%. The upstream signal a1 emitted by the tunable laser reaches the first reflective layer 23 of the WDM filter for the first time. Since the reflectivity is 10%, 90% of the uplink signal a1 is output according to the original emission direction, and 10% of the signal is reflected. To the second reflective layer 24. After the reflection of the second reflective layer 24, the 10% signal is totally reflected and reaches the first reflective layer 23 again. Part of the signal loss will occur, 1% of the signal will return in the opposite direction to the original emission direction, filtered by the splitter located in front of the laser, and finally 9% of the upstream signal will enter the adjustable under the WDM filter. Receiver. In summary, the upstream signal transmitted by the laser passes through the WDM filter, 90% of the output, and 9% enters the tunable receiver for subsequent initialization, and the remaining 1% is lost. Taking the power of the original signal emitted by the laser as +3dBm as an example, the final output power is 2.5dBm, and the power entering the tunable receiver is

-7.44dBm, the final loss of power is -17dBm; for normal receivers, the sensitivity is generally lower than -20dBm, so -7.44dBm is enough to meet the requirements of the receiver, and can be used for subsequent optical power detection, etc. deal with.

The reflectance of the second reflective layer may be 100%. In the specific implementation, it may be 99.99% or the like due to an error or the like.

Specifically, the principle of the tunable filter 18 is to adjust the passable wavelength (which may be referred to as the pass wavelength) so that the optical power received by the receiver is maximized only for optical signals that are identical to the pass wavelength. The filter characteristics of the tunable filter are fixed under the same conditions. For each batch of the same tunable filter, the filter parameters corresponding to each wavelength in the tunable wavelength range are also consistent, that is, according to these parameters. The filters can be set to corresponding set wavelengths, which are stored in the memory 13 shown in Figure 1; the processor 12 can set the receive wavelength (i.e., the pass wavelength) of the tunable filter 18 based on these parameters.

In this embodiment, since the wavelength of the tunable filter 18 needs to be set during the initialization process The initialization target wavelength of the tunable laser 14 is obtained, and the initialization target wavelength is finally obtained by power detection from the first wavelength range of the tunable laser 14, so that the tunable wavelength range of the tunable filter 18 (second The wavelength range) needs to include the first wavelength range of the tunable laser 14. For example, the first wavelength range is from 1530 nm to 1539 nm, and the second wavelength range is from 1528 nm to 1550 nm, which satisfies the above requirements.

Specifically, the receiver 19 in the tunable receiver 17 can convert an uplink signal (the uplink signal is an optical signal sent by the ONU to the OLT) into an electrical signal, and process the electrical signal to obtain a signal power; The signal power is sent to the processor 12; for example, the power signal can be amplified by an amplifier and converted to a digital signal for transmission to the processor 12.

After receiving the signal power of the uplink signal from the tunable receiver 17, the processor 12 may compare the signal power of the uplink signal in the first wavelength range, and obtain the maximum signal power from which the maximum signal power corresponds. The uplink signal is an uplink signal that coincides with the pass wavelength of the tunable filter 18, that is, an uplink signal having an initialization target wavelength. At this time, the processor 12 may also acquire the tunable laser parameter corresponding to the uplink signal corresponding to the initialization target wavelength, and store the tunable laser parameter to the memory 13 to complete the wavelength initialization of the tunable laser; the subsequent processor 12 The tunable laser 14 can be controlled to emit an up signal having an initialization target wavelength based on the tunable laser parameters.

In this embodiment, the processor 12 processes a digital signal, and the control signal used to control the tunable laser 14 is an analog signal, and the uplink signal power obtained by the tunable receiver is also an analog signal. Therefore, in a specific implementation, the processor The amount of 12 transmitted to the tunable laser 14 and the tunable filter 18 requires digital to analog conversion, and the amount of feedback from the tunable laser 14, the tunable filter 18, etc. to the processor 12 requires analog to digital conversion.

The working principle of the tunable laser wavelength initializing system of the present embodiment will be described below. First, the pass wavelength of the tunable filter 18 is adjusted to the initializing target wavelength of the tunable laser 14; then, the tunable laser 14 is adjusted to make the tunable The laser 14 emits an uplink signal in a first wavelength range, and the wavelength division multiplexer 16 reflects the uplink signal such that a portion of the uplink signal enters the tunable receiver 17, wherein the first wavelength range coincides with the initialization target wavelength ( That is, the signal that is strictly aligned can pass the maximum signal power; then, the processor 12 detects the signal power of the uplink signal in the first wavelength range received by the tunable receiver 17, and obtains the uplink signal corresponding to the maximum signal power. The upstream signal corresponding to the maximum signal power is the initializing target wavelength of the tunable laser Corresponding uplink signal, the processor 12 obtains the tunable laser parameter corresponding to the signal, and stores it in the memory 13, so that the wavelength initialization of the tunable laser 14 can be completed. If there are multiple initialization target wavelengths of the tunable laser 14, the multiple wavelengths need to be initialized separately according to the above method. After the initialization is completed, the pass wavelength of the tunable receiver 17 can be adjusted to the band of the downlink signal, and the uplink signal can be filtered out without affecting the reception of the downlink signal.

In the tunable laser wavelength initialization system of the embodiment, the processor detects the signal power of the uplink signal received by the tunable receiver, and the uplink signal is an uplink signal in the first wavelength range of the tunable laser, and obtains the The uplink signal corresponding to the maximum signal power in the first wavelength range is an uplink signal corresponding to the initialization target wavelength, and the processor can control the tunable laser to transmit the uplink signal having the initialization target wavelength, thereby implementing the tunable laser Compared with the prior art, the method is completed by a functional unit in the access network device itself, such as a tunable laser and a tunable receiver. It is no longer necessary to add additional AWG and OLT cooperation, which simplifies. The wavelength initialization process reduces the initialization cost.

Embodiment 2

3 is a schematic structural view of another embodiment of a tunable laser wavelength initialization system according to the present invention;

4 is a circuit schematic diagram of another embodiment of a tunable laser wavelength initialization system of the present invention. This embodiment is a distributed feedback (Distributed Feed Back, DFB) laser for laser wavelength adjustment using a semiconductor refrigerator (Thermoelectric Cooler, TEC for short) and Fabry-perot based on electrothermal adjustment. The tunable receiver of the FP filter is taken as an example, and the scheme of the first embodiment is described, but the present invention is not limited to the two devices. For example, the tunable laser is a distributed Bragg reflector (DBR) tunable laser or an external cavity tunable laser; the tunable filter is a tunable grating filter; It can be the operating current of the laser.

As shown in FIG. 3 and FIG. 4, in the system of the present embodiment, the tunable laser 14 uses a DFB laser using a TEC for laser wavelength adjustment, and the inside of the DFB laser is reflected by a Bragg grating to determine the output wavelength of the laser. Due to the temperature sensitivity of the Bragg grating, the temperature change causes the wavelength of the laser to drift, usually the temperature change rc, and the laser wavelength drifts by 0.09 nm. Based on this characteristic, different output wavelengths can be obtained by controlling the temperature to form the tunable laser 14. For example, by changing the temperature from 15 °C to 60 °C, the wavelength of the DFB laser changes from 1535 nm to 1539 nm, and the variation range is about 4 nm, which can be satisfied. System requirements for 100GHz*4Channel or 50GHz*8Channel.

The tunable filter 18 is based on an electrically adjustable FP filter. There are also many implementations of tunable filters. The most common one is to change the cavity length of the FP filter by changing the constraints, resulting in changes in the filter characteristics. The constraint can be temperature-induced deformation or can be implemented using a Micro-Electro-Mechanical Systems (MEMS). The electrothermally adjustable FP filter can achieve full coverage of the uplink and downlink wavelengths.

The processor 12 is the core controller of the entire circuit and can be a microcontroller or other microprocessor. The memory 13 is used to store the filter parameter values corresponding to the respective pass wavelengths (up and down) of the tunable filter 18, and the parameter values corresponding to the respective initialization target wavelengths of the up-tuning laser 14 obtained after the initialization process. The digital to analog converter is used to convert the digital command from the processor 12 that controls the wavelength of the laser into an analog quantity in the circuit for controlling the wavelength. An analog to digital converter is used to convert the temperature of the tunable laser 14 and the optical power received by the receiver 19 into a digital quantity that the processor 12 can recognize. The TEC is a temperature controller that regulates the temperature of the DFB laser. The thermistor is used to acquire the current actual operating temperature of the tunable laser 14. The receiver 19 can be a PIN junction photodiode (P-I-N, PIN for short) or an avalanche photodiode (APD).

Assuming that the tunable laser of the present embodiment has four initialization target wavelengths, it is necessary to determine laser parameters of four wavelengths. The following describes the working process of the tunable laser wavelength initialization system of the present embodiment: after the uplink signal transmitted by the tunable laser 14 passes through the WDM filter, most of the output is output according to the original transmission direction, and a small portion of the signal enters the tunable reception under the WDM filter. Machine 17. During the initialization process, the pass wavelength of the tunable filter 18 in the tunable receiver 17 is set to the initializing target wavelength of the tunable laser 14, and the tunable laser 14 is adjusted. When the tunable laser 14 emits the wavelength of the upstream signal, When the pass wavelength of the modulation filter 18 is fully aligned, the signal power received by the receiver 19 is maximized, and the processor 12 can obtain the uplink signal corresponding to the maximum signal power by power comparison. The processor 12 can obtain the tunable laser parameter corresponding to the maximum signal power signal, and store the parameter in the memory 13. The tunable laser parameter of the embodiment is the laser temperature. The pass wavelength of the device 18 is sequentially set to the four initialization target wavelengths, and the tunable laser parameters corresponding to the wavelength are obtained. After the initialization of all the wavelengths is completed, the pass wavelength of the tunable filter 18 is set at the receiving wavelength of the downlink signal, and the portion of the uplink signal used for the wavelength initialization is available. The filter 18 is filtered out and does not affect the reception of the downstream signal.

Embodiment 3

Embodiments of the present invention provide an optical network device including a tunable laser wavelength initialization system according to any embodiment of the present invention.

For example, the optical network device may be an optical network unit ONU, and the initialization target wavelength is an uplink working wavelength of the ONU. Alternatively, the optical network device can also be a tunable transceiver in an optical transport network.

Embodiment 4 The optical network device includes: a tunable laser, a wavelength division multiplexer, a tunable receiver, and a processor, wherein the wavelength division multiplexer is respectively connected to the tunable laser and the tunable receiver, The tuned receiver includes a tunable filter and a receiver, and the processor is respectively coupled to the receiver and the tunable laser; the method can be performed by the tunable laser wavelength initialization system of any embodiment of the present invention, this embodiment only The method is briefly described, and the specific process can be combined with other embodiments as described. As shown in FIG. 5, the method in this embodiment may include:

501, setting a receiving wavelength of the tunable filter to be an initializing target wavelength of the tunable laser;

502. The processor controls the tunable laser to transmit an uplink signal in a first wavelength range.

503. The wavelength division multiplexer reflects the uplink signal sent by the tunable laser, so that part of the uplink signal enters the tunable receiver, and the tunable receiver transmits the signal power of the uplink signal to the processor.

504. The processor detects a signal power of an uplink signal in the first wavelength range, and obtains a maximum signal power, where an uplink signal corresponding to the maximum signal power is an uplink signal corresponding to an initializing target wavelength of the tunable laser. And acquiring an uplink signal pair corresponding to the initialization target wavelength The tunable laser parameter is adapted to control the tunable laser to transmit an uplink signal corresponding to the initialization target wavelength according to the tunable laser parameter.

For example, the tunable laser parameter can be stored for the processor to control the tunable laser to transmit an uplink signal corresponding to the initialization target wavelength according to the tunable laser parameter.

In the tunable laser wavelength initialization method of the embodiment, the processor detects the signal power of the uplink signal received by the tunable receiver, and the uplink signal is an uplink signal in the first wavelength range of the tunable laser, and obtains the The uplink signal corresponding to the maximum signal power in the first wavelength range is an uplink signal corresponding to the initialization target wavelength, and the processor can control the tunable laser to transmit the uplink signal having the initialization target wavelength, thereby implementing the tunable laser Compared with the prior art, the method is completed by a functional unit in the access network device itself, such as a tunable laser and a tunable receiver. It is no longer necessary to add additional AWG and OLT cooperation, which simplifies. The wavelength initialization process reduces the initialization cost.

A person skilled in the art can understand that all or part of the steps of implementing the foregoing method embodiments may be implemented by hardware related to program instructions, and the foregoing program may be stored in a computer readable storage medium, and when executed, the program includes The foregoing steps of the method embodiment; and the foregoing storage medium includes: a medium that can store program codes, such as a ROM, a RAM, a magnetic disk, or an optical disk.

Finally, it should be noted that the above embodiments are only for explaining the technical solutions of the present invention, and are not intended to be limiting thereof; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art will understand that The technical solutions described in the foregoing embodiments may be modified, or some or all of the technical features may be equivalently replaced; and the modifications or substitutions do not deviate from the technical solutions of the embodiments of the present invention. range.

Claims

Claim

A wavelength division multiplexer, comprising: a sidewall and an inner cavity surrounded by the sidewall; and further comprising:

a first reflective layer disposed in the inner cavity of the wavelength division multiplexer for opposing the tunable laser that emits the uplink signal, and disposed at an angle of 45 degrees to the emission direction of the uplink signal, for the reflective portion The uplink signal;

a second reflective layer disposed on a sidewall of the wavelength division multiplexer opposite to the first reflective layer and disposed perpendicular to an emission direction of the uplink signal reflected by the first reflective layer for use in reflecting The subsequent uplink signal is again reflected, such that the upstream signal passes through the first reflective layer and enters the tunable receiver from the wavelength division multiplexer for wavelength initialization of the tunable laser.

2. The wavelength division multiplexer according to claim 1, wherein a reflectance of the first reflective layer to an uplink signal transmitted by the tunable laser is 5% to -15%; The reflectance of the reflective layer is 100%.

3. A fiber optic bidirectional component, comprising: a wavelength division multiplexer; the fiber optic bidirectional component further comprising: a tunable transmitter and a tunable receiver, the tunable transmitter comprising a tunable laser for an uplink signal, the tunable receiver comprising a tunable filter and a receiver;

The wavelength division multiplexer is configured to reflect a portion of the uplink signal transmitted by the tunable laser into the tunable filter;

The receiver is configured to acquire signal power of an uplink signal received by the tunable filter.

The optical fiber bidirectional component according to claim 3, wherein the wavelength division multiplexer comprises: a sidewall and a cavity surrounded by the sidewall; and further comprising:

a first reflective layer disposed in the inner cavity of the wavelength division multiplexer for opposing the tunable laser that emits the uplink signal, and disposed at an angle of 45 degrees to the emission direction of the uplink signal, for the reflection portion Dividing the uplink signal;

The optical fiber bidirectional component according to claim 4, wherein a reflectance of the first reflective layer to an uplink signal emitted by the tunable laser is 5%-15%; the second reflective layer The reflectivity is 100%.

A tunable laser wavelength initialization system, comprising: a processor, a memory, and the optical fiber bidirectional component according to any one of claims 3-5;

7. The tunable laser wavelength initialization system according to claim 6, wherein the tunable laser is a distributed feedback DFB laser; and the tunable filter is based on an electrically adjustable Fabry-Perot FP. Filter; Correspondingly, the tunable laser parameter is a laser temperature.

8. An optical network device, comprising: the tunable laser wavelength initialization system of claim 6 or 7.

The optical network device according to claim 8, wherein the optical network device is an optical network unit ONU, and the initialization target wavelength is an uplink working wavelength of the ONU.

10. The optical network device according to claim 8, wherein the optical network device is a tunable transceiver.

A wavelength initialization method for an optical network device, wherein the optical network device comprises: a tunable laser, a wavelength division multiplexer, a tunable receiver, and a processor, wherein the wavelength division multiplexer and the The tunable laser is coupled to a tunable receiver, the tunable receiver including a tunable filter and a receiver, the processor being coupled to the receiver and the tunable laser, respectively; Methods include:

Setting the receiving wavelength of the tunable filter to be the initializing target wavelength of the tunable laser;

The processor detects the signal power of the uplink signal in the first wavelength range, and obtains the maximum signal power, where the uplink signal corresponding to the maximum signal power is an uplink signal corresponding to the initializing target wavelength of the tunable laser, and acquires The tunable laser parameter corresponding to the maximum signal power is used to control the tunable laser to transmit an uplink signal corresponding to the initialization target wavelength according to the tunable laser parameter.