Device, equipment and method for adjusting output power of coherent burst receiving local oscillator laser

Abstract

The invention discloses a device, equipment and a method for adjusting the output power of a coherent burst receiving local oscillator laser, and relates to the technical field of coherent optical communication. The device comprises a burst coherent receiving assembly which is used for completing photoelectric conversion and amplifying an electric signal; a power high-low threshold value and a power and LO bias current relation table are arranged in the burst processing control unit, and the burst processing control unit is used for correcting the deviation, comparing the corrected signal light and the optical power after frequency mixing of the local oscillation light with the power high-low threshold value, and outputting a power control signal according to a comparison result in combination with the power and LO bias current relation table; and the local oscillator laser and the control unit thereof adjust the output light power according to the power control signal. By dynamically adjusting the laser power of the LO, the OLT can dynamically adjust the light receiving power within the threshold range according to the intensity of the light receiving signal, so that the signals of all ONUs can be completely recovered, and the requirement of applying the coherent technology to the field of optical access networks is met.

Description

Technical Field

[0001] The present invention relates to the technical field of coherent optical communication, and in particular to a device, equipment and method for adjusting the output power of a coherent burst receiving local oscillator laser. Background Art

[0002] Coherence has been widely used in point-to-point transmission and data centers. At the coherent receiving end, the signal light and the local oscillator (hereinafter referred to as LO, Local Oscillator) are mixed and then output to the diode for photoelectric conversion. Since the coherence used in transmission and data centers is a point-to-point system, the signal light power received by the receiving end remains basically unchanged. Therefore, the LO output light power can remain unchanged to ensure the normal reception of the signal. Figure 1 shown.

[0003] In the field of optical access network, when 50G TDM-PON evolves to 100G and above PON, the coherent technology route is the preferred choice. When coherent technology is applied to the TDM-PON system, the OLT (Optical Line Terminal) receiving side will receive different ONU (Optical Network Unit) signal light at different times in a time division multiple access mode (i.e., TDMA). Due to the different distances between each ONU and the differences in branch links, the power of the signal light received by the OLT will be different. If the receiving end on the OLT side does not have the ability to quickly process sudden changes in optical power, when the optical signal of the ONU with a longer or shorter distance and a larger or smaller optical power attenuation reaches the OLT, the optical signal will be restored to an erroneous signal because the optical power level is less than or higher than the threshold (it is considered valid only within the threshold range, and cannot be correctly restored if it is lower or higher than the threshold).

[0004] Therefore, if coherent technology is to be applied to the field of optical access networks, it is urgent to solve the problem of adjusting the output optical power of the local oscillator laser LO under coherent burst reception on the OLT side to ensure that the signals of all ONUs can be fully restored. Summary of the invention

[0005] The purpose of the present invention is to overcome the shortcomings of the above-mentioned background technology and provide a coherent burst receiving local oscillator laser output power adjustment device, equipment and method, which can dynamically adjust the laser power of LO so that the OLT can dynamically adjust the received light power within the threshold range according to the intensity of the received light signal to ensure that the signals of all ONUs can be completely restored, meeting the needs of applying coherent technology to the field of optical access networks.

[0006] To achieve the above objectives, in a first aspect, an embodiment of the present invention provides a coherent burst receiving local oscillator laser output power adjustment device, comprising:

[0007] A burst coherent receiving component is used to: complete the photoelectric conversion and amplify the electrical signal, and output the signal data to the burst processing control unit;

[0008] A burst processing control unit, which is internally provided with power high and low threshold values ​​and a power and LO bias current relationship table, is used to: correct the frequency offset of the local oscillator laser; and compare the optical power of the corrected signal light and the local oscillator light after mixing with the power high and low threshold values, and output a corresponding power control signal to the local oscillator laser and its control unit according to the comparison result and in combination with the power and LO bias current relationship table;

[0009] A local oscillator laser and a control unit thereof are used to adjust the output optical power according to a received power control signal.

[0010] In combination with the first aspect, in one implementation, the burst processing control unit corrects the frequency offset of the local oscillator laser, including:

[0011] The burst processing control unit detects the initial frequency f of the local oscillator laser Lo The signal frequency f of the ONU burst signal light s The frequency deviation Δf, Δf = f s -f Lo ;

[0012] If the positive bias Δf>+Δf0, Δf0 is the normal frequency range agreed by the system, then the positive bias frequency adjustment control signal is output to the local oscillator laser control unit, so that it adjusts the local oscillator laser frequency toward the high frequency direction until Δf is within Δf0;

[0013] If the negative bias Δf is less than -Δf0, a negative bias frequency adjustment control signal is output to the local oscillator laser control unit to adjust the local oscillator laser frequency toward a low frequency until Δf is within Δf0.

[0014] In combination with the first aspect, in one implementation, the burst processing control unit compares the optical power of the signal light after deflection correction and the local oscillator light after mixing with the power high and low threshold values, and outputs a corresponding power control signal to the local oscillator laser and its control unit according to the comparison result and in combination with the power and LO bias current relationship table, including:

[0015] The burst processing control unit detects the optical power of the corrected signal light and the local oscillator light after mixing, and compares it with the high and low power thresholds;

[0016] If it is greater than the power high threshold value, a power adjustment control signal for reducing the power is output to the local oscillator laser control unit according to the power and LO bias current mapping table;

[0017] If it is less than the low power threshold, a power adjustment control signal for increasing the power is output to the local oscillator laser control unit according to the power and LO bias current mapping table.

[0018] In combination with the first aspect, in one embodiment, the burst processing control unit is also used to: determine whether the adjusted optical power is within the power high and low threshold values; if so, control the local oscillator laser to output the adjusted power and end the current adjustment; otherwise, repeat the adjustment until the adjusted optical power is within the power high and low threshold values.

[0019] In combination with the first aspect, in one implementation, the burst coherent receiving component includes:

[0020] The first device is used to: complete polarization splitting of the signal light and the local oscillator laser light signal;

[0021] The second device is used to: complete the mixing output of the optical signal;

[0022] The third device is used to: complete photoelectric conversion and output current;

[0023] The fourth device is used to convert the current into a voltage signal and amplify the voltage signal and output it to the burst processing control unit.

[0024] In combination with the first aspect, in one embodiment, the first device includes a polarization beam splitter; the second device includes a 90° mixer or a 2×2 coupler; the third device includes a balanced diode or a single diode; and the fourth device includes a transimpedance amplifier.

[0025] In combination with the first aspect, in one implementation, if the receiving end is a dual-polarization receiving mode, the first device of the burst coherent receiving component is a polarization beam splitter, the second device is a 90° mixer, the third device is a balanced diode, and the fourth device is a transimpedance amplifier.

[0026] In combination with the first aspect, in one implementation, if the receiving end is a single polarization receiving mode, the burst coherent receiving component omits the first device, and the second device is a 2×2 coupler, the third device is a balanced diode, and the fourth device is a transimpedance amplifier.

[0027] In combination with the first aspect, in one implementation, if the receiving end is a single-polarization minimalist receiving mode, the burst coherent receiving component omits the first device, and the second device is a 2×2 coupler, the third device is a single diode, and the fourth device is a transimpedance amplifier.

[0028] In a second aspect, an embodiment of the present invention further provides an OLT device, in which the coherent burst receiving local oscillator laser output power adjustment device of the embodiment of the first aspect is provided.

[0029] In a third aspect, an embodiment of the present invention further provides a method for adjusting the output power of a coherent burst receiving local oscillator laser based on the device in the embodiment of the first aspect, the method comprising the following steps:

[0030] The burst coherent receiving component receives the burst signal light from different ONUs and the light output by the local oscillator laser, completes the photoelectric conversion and outputs the amplified electrical signal to the burst processing control unit;

[0031] The burst processing control unit corrects the frequency deviation of the local oscillator laser; and compares the optical power of the corrected signal light and the local oscillator light after mixing with the built-in power high and low threshold values, and outputs the corresponding power control signal to the local oscillator laser and its control unit based on the comparison result and the built-in power and LO bias current relationship table;

[0032] The local oscillator laser and its control unit adjust the output optical power according to the received power control signal.

[0033] The beneficial effects brought by the technical solution provided by the embodiments of the present application include:

[0034] The embodiments of the present application achieve the ability to adjust the output optical power of the local oscillator laser during coherent burst reception, thereby increasing the dynamic range of coherent burst reception, thereby solving the problem of bit errors caused by different received signal light sizes when OLT burst reception and the output optical power of the OLT local oscillator laser is fixed in the prior art, and meeting the needs of applying coherent technology to the field of optical access networks. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 The block diagram of the existing point-to-point coherent receiving system is as follows;

[0036] Figure 2 The following is a block diagram of an existing burst coherent receiving system;

[0037] Figure 3 This is a functional module diagram of the first embodiment of the coherent burst receiving local oscillator laser output power adjustment device of the present application;

[0038] Figure 4 Schematic diagram of the relationship between LO frequency and optical power after mixing;

[0039] Figure 5 A schematic diagram of the relationship between the received power and the bit error rate of a burst coherent receiving component;

[0040] Figure 6This is a schematic diagram of the functional modules of the burst coherent receiving component in the embodiment of the present application;

[0041] Figure 7 This is a flow chart of a first embodiment of a method for adjusting the output power of a local oscillator laser for coherent burst reception according to the present application;

[0042] Figure 8 It is a schematic diagram of a coherent burst receiving local oscillator laser output power adjustment device based on dual polarization reception in an example;

[0043] Fig. 9 The figure is a flow chart of a method for adjusting the output power of a local oscillator laser for coherent burst reception based on dual-polarization reception in an example. DETAILED DESCRIPTION

[0044] First, the design idea of ​​the present invention is further explained: the present invention is intended to solve the problem that the output power of the local oscillator laser LO needs to be adjusted under coherent burst reception on the OLT side, so as to ensure that the signals of all ONUs can be completely restored.

[0045] Specifically, when coherent technology is applied to the field of optical access networks, especially to point-to-multipoint coherent PON systems, the optical power of the ONUs received by the OLT will be different because the OLT receiving side will receive optical signals from different ONUs, and the distances between the ONUs and the OLT are different, and the link conditions are different. Figure 2 As shown in the figure, the ICR (Integrated Coherent Receiver) with a built-in TIA (Trans-Impedance Amplifier) ​​will receive burst signal light from different ONUs with different optical powers. If the LO output optical power on the OLT side is a fixed value, after coherence with the ONU that receives lower optical power, the output signal will be smaller, lower than the lower threshold of the judgment, resulting in line errors (i.e., recovering the wrong signal); conversely, if it is coherent with the ONU that receives higher optical power, the output signal will be too large, higher than the upper threshold of the judgment, resulting in line errors (i.e., recovering the wrong signal). The above situations will affect the normal communication of the equipment, and thus fail to meet the needs of applying coherent technology to the field of optical access networks.

[0046] In order to solve the above problems, the solution proposed by the present invention is: a coherent burst receiving local oscillator laser output power adjustment device is designed on the OLT side, the burst coherent receiving component in the device receives the burst signal light from different ONUs and the light output by the local oscillator laser, completes the photoelectric conversion and outputs the amplified electrical signal to the burst processing control unit; the burst processing control unit is then used to correct the frequency offset of the local oscillator laser; and the optical power of the corrected signal light and the local oscillator light after mixing is compared with the built-in power high and low threshold values, and according to the comparison result and in combination with the built-in power and LO bias current relationship table, a corresponding power control signal is output to the local oscillator laser and its control unit; finally, the local oscillator laser and its control unit can adjust the output optical power according to the received power control signal.

[0047] In this solution, the laser power of the LO in the OLT can be dynamically adjusted so that the OLT can dynamically adjust the received light power within the threshold range according to the intensity of the received light signal to ensure that the signals of all ONUs can be fully restored, meeting the needs of applying coherent technology to the field of optical access networks.

[0048] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0049] In order to make the objectives, technical solutions and advantages of the present application clearer, the implementation methods of the present application will be further described in detail below in conjunction with the accompanying drawings.

[0050] In a first aspect, an embodiment of the present application provides a coherent burst receiving local oscillator laser output power adjustment device.

[0051] In one embodiment, referring to Figure 3 As shown, Figure 3 This is a functional module diagram of the first embodiment of the coherent burst receiving local oscillator laser output power adjustment device of the present application. Figure 3 As shown, a coherent burst receiving local oscillator laser output power adjustment device is provided in a burst coherent receiving end (such as an OLT device), comprising:

[0052] The burst coherent receiving component is used to complete the photoelectric conversion and amplify the electrical signal, and output the signal data to the burst processing control unit.

[0053] The burst processing control unit is internally provided with power high and low threshold values ​​and a power and LO bias current relationship table, which is used to: correct the frequency deviation of the local oscillator laser; and compare the optical power of the corrected signal light and the local oscillator light after mixing with the power high and low threshold values, and output the corresponding power control signal to the local oscillator laser and its control unit according to the comparison result and the power and LO bias current relationship table, so as to complete the adjustment and control of the output optical power of the local oscillator laser. It can be understood that, if Figure 3 As shown, the burst processing control unit, while completing the adjustment and control of the output optical power of the local oscillator laser, will also send the processed signal data to the subsequent PON MAC protocol unit for data transmission. In practical applications, the power high and low threshold values ​​and the power and LO bias current relationship table can be pre-built into the burst processing control unit, but later according to the specific usage, they can still be adjusted and set accordingly through the device's external chip communication interface (such as SPI, MDIO, etc.). Among them, the power high and low threshold values ​​include a high power threshold value and a low power threshold value; within the high power threshold value and the low power threshold value, the signal is normal, the signal has no bit error or the signal bit error rate can be corrected to no bit error through the forward error correction method of the PONMAC protocol unit; if it exceeds the high power threshold value or is lower than the low power threshold value, the signal is abnormal, which will cause the system bit error rate BER1, which cannot be corrected to no bit error through the subsequent error correction method, and the system cannot work normally.

[0054] A local oscillator laser and a control unit thereof are used to adjust the output optical power according to a received power control signal.

[0055] It is understandable that since the local oscillator laser needs to lock the frequency to the signal frequency, any deviation will affect the output optical power after mixing, such as Figure 4 As shown, in this embodiment, a frequency difference processing function is designed in the burst processing control unit, that is, the burst processing control unit will first determine the frequency offset of the local oscillator laser, and correct the frequency offset, so as to control the frequency offset (frequency difference) within the system requirement range. In addition, the power high and low thresholds are set because the transimpedance amplifier in the burst coherent receiving component has a linear amplification region. If it is within the threshold, it is in the linear region and the system can work normally. If the received electrical signal is too high or too low, it will exceed the linear region, resulting in system errors and failure to work normally. Figure 5As shown. Therefore, in order to prevent the signal from entering the nonlinear region, the burst processing control unit in this embodiment will compare the optical power of the signal light after deviation correction and the local oscillator light after mixing with the high and low power threshold values, and output the corresponding power control signal according to the comparison result and in combination with the power and LO bias current relationship table, so as to control and adjust the output power of the local oscillator laser. It is also based on the above functional design that the device of this embodiment can use the burst processing control unit to dynamically adjust the laser power of the LO so that the OLT dynamically adjusts the received light power within the threshold value (threshold value) according to the intensity of the received light signal, so as to ensure that the signals of all ONUs can be completely restored without bit errors, thereby meeting the needs of applying coherent technology to the field of optical access networks.

[0056] Further, as an optional implementation manner, in this embodiment, the burst processing control unit corrects the frequency offset of the local oscillator laser, specifically including:

[0057] 1. The burst processing control unit detects the initial frequency f of the local oscillator laser Lo The signal frequency f of the ONU burst signal light s The frequency deviation Δf, Δf = f s -f Lo ; Among them, the initial frequency f of the local oscillator laser Lo It is pre-built into the local oscillator laser and its control unit, and the burst processing control unit can obtain and save the corresponding information from it; generally speaking, the initial frequency f Lo There is no need to adjust it later, but in specific applications, you can still make corresponding adjustments and settings through the device's external chip communication interface (such as SPI, MDIO, etc.) according to actual needs;

[0058] 2. If the positive deviation Δf>+Δf0, Δf0 is the normal frequency range agreed by the system, the burst processing control unit outputs a positive frequency adjustment control signal to the local oscillator laser control unit, so that it adjusts the local oscillator laser frequency toward high frequency until the frequency deviation Δf is within the normal frequency range Δf0 agreed by the system; currently, the normal frequency range Δf0 agreed by the system is usually 100Mhz;

[0059] 3. If the negative bias Δf is less than -Δf0, the burst processing control unit outputs a negative bias frequency adjustment control signal to the local oscillator laser control unit, so that it adjusts the local oscillator laser frequency toward the low frequency direction until the frequency deviation Δf is within the normal frequency range Δf0 agreed by the system.

[0060] Further, as an optional implementation, in this embodiment, the burst processing control unit compares the optical power of the signal light after deflection correction and the local oscillator light after mixing with the high and low power thresholds, and outputs a corresponding power control signal to the local oscillator laser and its control unit according to the comparison result and in combination with the power and LO bias current relationship table, specifically including:

[0061] 1. The burst processing control unit detects the optical power of the corrected signal light and the local oscillator light after mixing, and compares it with the high and low power thresholds;

[0062] 2. If it is greater than the high power threshold, the power adjustment control signal is output to the local oscillator laser control unit according to the power and LO bias current mapping table, so that it reduces the output optical power of the local oscillator laser. The step size of the reduction is determined according to the actual system;

[0063] 3. If it is less than the low power threshold, the power adjustment control signal is output to the local oscillator laser control unit according to the power and LO bias current mapping table, so that it increases the output optical power of the local oscillator laser. The step size of the increase is determined according to the actual system.

[0064] It is understandable that, since the step size of each adjustment is determined according to the actual system, there may be a situation where one adjustment cannot adjust the output optical power of the local oscillator laser to within the power threshold. Therefore, in order to ensure the effectiveness of the adjustment, in actual applications, the burst processing control unit is also used to: determine whether the adjusted optical power is within the high and low power thresholds; if so, control the local oscillator laser to output the adjusted power and end this adjustment; otherwise, repeat the adjustment (i.e. repeat steps 1 to 3 above) until the adjusted optical power is within the high and low power thresholds.

[0065] Further, refer to Figure 6 As shown, as an optional implementation manner, in this embodiment, the burst coherent receiving component includes:

[0066] The first device is used to: complete polarization splitting of the signal light and the local oscillator laser light signal;

[0067] The second device is used to: complete the mixing output of the optical signal;

[0068] The third device is used to: complete photoelectric conversion and output current;

[0069] The fourth device is used to convert the current into a voltage signal and amplify the voltage signal and output it to the burst processing control unit.

[0070] Among them, the first device may be a polarization beam splitter; the second device may be a 90° mixer or a 2×2 coupler; the third device may be a balanced diode or a single diode; the fourth device may be a transimpedance amplifier. It is understandable that in specific practical applications, since the receiving mode of the coherent system receiving end may be different (such as a single polarization receiving mode, a dual polarization receiving mode or a simplified coherent receiving mode, etc.), the specific composition of the burst coherent receiving component may be different.

[0071] Exemplarily, if the receiving end is a dual-polarization receiving mode, the first device is a polarization beam splitter, the second device is a 90° mixer, the third device is a balanced diode, and the fourth device is a transimpedance amplifier. If the receiving end is a single-polarization receiving mode, the first device can be omitted from the burst coherent receiving component, and the second device is a 2×2 coupler, the third device is a balanced diode, and the fourth device is a transimpedance amplifier. If the receiving end is a single-polarization minimalist receiving mode, the first device can be omitted from the burst coherent receiving component, and the second device is a 2×2 coupler, the third device is a single diode, and the fourth device is a transimpedance amplifier.

[0072] It can be seen that the device of this embodiment can be used to apply different receiving schemes according to the requirements of the system, has a wide range of applications and is flexible to use, and meets actual application needs.

[0073] In the second aspect, the embodiment of the present application provides an OLT device, in which the coherent burst receiving local oscillator laser output power adjustment device of the embodiment of the first aspect is provided. The OLT device can dynamically adjust the laser power of the LO by using the internal adjustment device so that the OLT dynamically adjusts the received light power within the threshold range according to the intensity of the received light signal, so as to ensure that the signals of all ONUs can be completely restored, and meet the requirements of the application of coherent technology in the field of optical access networks.

[0074] In a third aspect, an embodiment of the present application provides a method for adjusting the output power of a coherent burst receiving local oscillator laser based on the device in the embodiment of the first aspect.

[0075] In one embodiment, referring to Figure 7 As shown, Figure 7 This is a flow chart of the first embodiment of the method for adjusting the output power of the local oscillator laser for coherent burst reception of the present application. Figure 7 As shown, a method for adjusting the output power of a coherent burst receiving local oscillator laser includes:

[0076] Step A, the burst coherent receiving component receives the burst signal light from different ONUs and the light output by the local oscillator laser, completes the photoelectric conversion and outputs the amplified electrical signal to the burst processing control unit;

[0077] Step B, the burst processing control unit corrects the frequency offset of the local oscillator laser; and compares the optical power of the corrected signal light and the local oscillator light after mixing with the built-in power high and low threshold values, and outputs a corresponding power control signal to the local oscillator laser and its control unit according to the comparison result and in combination with the built-in power and LO bias current relationship table;

[0078] Step C: The local oscillator laser and its control unit adjust the output optical power according to the received power control signal.

[0079] It should be noted that the various variations and specific examples in the above-mentioned device embodiment are also applicable to the method of this embodiment. Through the detailed description of the above-mentioned device, those skilled in the art can clearly know the various implementation methods of the method in this embodiment, so for the sake of brevity of the specification, they will not be repeated here.

[0080] In order to better understand the coherent burst receiving local oscillator laser output power adjustment device and method of the present application, the device and method of the present application will be described in detail below with reference to the accompanying drawings, taking the application scenario of the dual-polarization receiving mode as an example.

[0081] Reference Figure 8 As shown, Figure 8 Schematic diagram of a coherent burst receiving local oscillator laser output power adjustment device based on dual polarization reception. Figure 8 As shown, a coherent burst receiving local oscillator laser output power adjustment device includes: a local oscillator laser and its control unit, a burst coherent receiving component and a burst processing control unit. Among them, the burst coherent receiving component is mainly composed of a polarization beam splitter, a 90° mixer, a balanced diode and a transimpedance amplifier; the burst processing control unit is pre-set with power high and low threshold values ​​and a power and LO bias current relationship table, the power high threshold value is recorded as Ph, and the power low threshold value is recorded as Pl; the local oscillator laser and its control unit are pre-set with the local oscillator laser's initial frequency f Lo The control unit can adjust the output optical power accordingly according to the control signal of the burst processing control unit.

[0082] Reference Fig. 9 As shown, Fig. 9 FIG. 1 is a flow chart of a method for adjusting the output power of a local oscillator laser for coherent burst reception based on dual polarization reception. Fig. 9 As shown, a method for adjusting the output power of a coherent burst receiving local oscillator laser comprises the following steps:

[0083] S901, the burst coherent receiving component receives the burst signal light from different ONUs and the light output by the local oscillator laser, completes the photoelectric conversion and outputs the amplified electrical signal to the burst processing control unit;

[0084] S902, the burst processing control unit detects the initial frequency f of the local oscillator laser Lo The signal frequency f of the ONU burst signal light s The frequency deviation Δf, Δf = f s -f Lo ; If it is a positive bias Δf>+Δf0, the burst processing control unit outputs a positive bias frequency adjustment control signal to the local oscillator laser control unit, so that it adjusts the local oscillator laser frequency toward the high frequency direction until the frequency deviation Δf is within the normal frequency range Δf0 agreed by the system; if it is a negative bias Δf<-Δf0, the burst processing control unit outputs a negative bias frequency adjustment control signal to the local oscillator laser control unit, so that it adjusts the local oscillator laser frequency toward the low frequency direction until the frequency deviation Δf is within the normal frequency range Δf0 agreed by the system;

[0085] S903, the burst processing control unit detects the output optical power after the signal light after the correction and the local oscillator light are mixed, which is recorded as Po.

[0086] S904, determine whether the current Po is within the power high and low threshold values ​​[Pl, Ph], if so, proceed to step S905; otherwise, proceed to step S906;

[0087] S905, controlling the local oscillator laser to output the adjusted power, and ending this adjustment;

[0088] S906, determine whether the current Po is higher than the high power threshold value Ph or lower than the low power threshold value Pl, if higher than Ph, proceed to step S907; if lower than Pl, proceed to step S908;

[0089] S907, according to the power and LO bias current mapping table, output a power adjustment control signal to the local oscillator laser control unit to reduce the local oscillator laser output optical power, the reduction step is determined according to the actual system, and Po is updated to return to step S904;

[0090] S908. According to the power and LO bias current mapping table, output a power adjustment control signal to the local oscillator laser control unit to increase the output optical power of the local oscillator laser. The step size of the increase is determined according to the actual system, and Po is updated to return to step S904.

[0091] From the above content, it can be seen that the device and method of the present application realize the ability to adjust the output optical power of the local oscillator laser during coherent burst reception, thereby increasing the dynamic range of coherent burst reception, thereby solving the bit error problem caused by different received signal light sizes when OLT burst reception and the output optical power of the OLT local oscillator laser is fixed.

[0092] Note: The above-mentioned specific embodiments are only examples rather than limitations, and those skilled in the art can, based on the concept of the present invention, merge and combine some steps and devices from the various embodiments described separately above to achieve the effects of the present invention. Such merged and combined embodiments are also included in the present invention, and such merges and combinations are not described one by one here.

[0093] The advantages, strengths, effects, etc. mentioned in the embodiments of the present invention are only examples, not limitations, and it cannot be considered that these advantages, strengths, effects, etc. must be possessed by each embodiment of the present invention. In addition, the above specific details disclosed in the embodiments of the present invention are only for the purpose of illustration and facilitating understanding, not limitation, and the above details do not limit the embodiments of the present invention to be implemented by adopting the above specific details.

[0094] The block diagrams of the devices, apparatuses, equipment, and systems involved in the embodiments of the present invention are only illustrative examples, and are not intended to require or imply that they must be connected, arranged, and configured in the manner shown in the block diagrams. As will be appreciated by those skilled in the art, these devices, apparatuses, equipment, and systems may be connected, arranged, and configured in any manner. Words such as "including," "comprising," "having," and the like are open words, meaning "including but not limited to," and may be used interchangeably therewith. The words "or" and "and" used in the embodiments of the present invention refer to the words "and / or," and may be used interchangeably therewith, unless the context clearly indicates otherwise. The words "such as" used in the embodiments of the present invention refer to the phrase "such as but not limited to," and may be used interchangeably therewith.

[0095] The step flow charts and the above method descriptions in the embodiments of the present invention are only illustrative examples, and are not intended to require or imply that the steps of each embodiment must be performed in the order given. As will be appreciated by those skilled in the art, the order of the steps in the above embodiments can be performed in any order. Words such as "thereafter", "then", "next", etc. are not intended to limit the order of the steps; these words are only used to guide the reader through the description of these methods. In addition, any reference to a singular element, such as using the article "a", "an", or "the", is not to be construed as limiting the element to the singular.

[0096] In addition, the steps and devices in each embodiment of the present invention are not limited to be implemented in a certain embodiment. In fact, according to the concept of the present invention, relevant partial steps and partial devices in each embodiment of this document can be combined to conceive new embodiments, and these new embodiments are also included in the scope of the present invention.

[0097] Each operation in the embodiment of the present invention may be performed by any appropriate means capable of performing the corresponding functions, which may include various hardware and / or software components and / or modules, including but not limited to hardware circuits or processors.

[0098] The method of the embodiment of the present invention includes one or more actions for implementing the above-mentioned method. The method and / or action can be interchangeable with each other without departing from the scope of the claims. In other words, unless a specific order of actions is specified, the order and / or use of specific actions can be modified without departing from the scope of the claims.

[0099] Various changes, substitutions and modifications of the techniques described herein may be made by those skilled in the art without departing from the teachings defined by the appended claims. In addition, the scope of the claims of the present disclosure is not limited to the specific aspects of the processes, machines, manufactures, components of events, means, methods and actions described above. Currently existing or later to be developed processes, machines, manufactures, components of events, means, methods or actions that perform substantially the same functions or achieve substantially the same results as the corresponding aspects described herein may be utilized. Thus, the appended claims include such processes, machines, manufactures, components of events, means, methods or actions within their scope.

[0100] The above description of the disclosed aspects is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these aspects will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other aspects without departing from the scope of the present invention. Therefore, the present invention is not intended to be limited to the aspects shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

[0101] The above description has been given for the purpose of illustration and description. In addition, this description is not intended to limit the embodiments of the present invention to the forms disclosed herein. Although a number of example aspects and embodiments have been discussed above, those skilled in the art will recognize certain variations, modifications, changes, additions and sub-combinations thereof. And the content not described in detail in this specification belongs to the prior art known to those skilled in the art.

Claims

1. A coherent burst receiving local oscillator laser output power adjustment device, characterized in that: The device includes: A burst coherent receiving component is used to: complete the photoelectric conversion and amplify the electrical signal, and output the signal data to the burst processing control unit; A burst processing control unit, which is internally provided with power high and low threshold values ​​and a power and LO bias current relationship table, is used to: correct the frequency offset of the local oscillator laser; and compare the optical power of the corrected signal light and the local oscillator light after mixing with the power high and low threshold values, and output a corresponding power control signal to the local oscillator laser and its control unit according to the comparison result and in combination with the power and LO bias current relationship table; A local oscillator laser and a control unit thereof are used to adjust the output optical power according to a received power control signal.

2. The coherent burst receiving local oscillator laser output power adjustment device according to claim 1, characterized in that: The burst processing control unit corrects the frequency deviation of the local oscillator laser, including: The burst processing control unit detects the initial frequency f of the local oscillator laser Lo The signal frequency f of the ONU burst signal light s The frequency deviation Δf, Δf = f s -f Lo ; If the positive bias Δf>+Δf0, Δf0 is the normal frequency range agreed by the system, then the positive bias frequency adjustment control signal is output to the local oscillator laser control unit, so that it adjusts the local oscillator laser frequency toward the high frequency direction until Δf is within Δf0; If the negative bias Δf is less than -Δf0, a negative bias frequency adjustment control signal is output to the local oscillator laser control unit to adjust the local oscillator laser frequency toward a low frequency until Δf is within Δf0.

3. The coherent burst receiving local oscillator laser output power adjustment device according to claim 1, characterized in that: The burst processing control unit compares the optical power of the signal light after deflection correction and the local oscillator light after mixing with the high and low power thresholds, and outputs a corresponding power control signal to the local oscillator laser and its control unit according to the comparison result and in combination with the power and LO bias current relationship table, including: The burst processing control unit detects the optical power of the corrected signal light and the local oscillator light after mixing, and compares it with the high and low power thresholds; If it is greater than the power high threshold value, a power adjustment control signal for reducing the power is output to the local oscillator laser control unit according to the power and LO bias current mapping table; If it is less than the low power threshold, a power adjustment control signal for increasing the power is output to the local oscillator laser control unit according to the power and LO bias current mapping table.

4. The coherent burst receiving local oscillator laser output power adjustment device as claimed in claim 3, characterized in that: The burst processing control unit is also used to: determine whether the adjusted optical power is within the power high and low threshold values; if so, control the local oscillator laser to output the adjusted power and end this adjustment; otherwise, repeat the adjustment until the adjusted optical power is within the power high and low threshold values.

5. The coherent burst receiving local oscillator laser output power adjustment device according to claim 1, characterized in that: The burst coherent receiving component comprises: The first device is used to: complete polarization splitting of the signal light and the local oscillator laser light signal; The second device is used to: complete the mixing output of the optical signal; The third device is used to: complete photoelectric conversion and output current; The fourth device is used to convert the current into a voltage signal and amplify the voltage signal and output it to the burst processing control unit.

6. The coherent burst receiving local oscillator laser output power adjustment device as claimed in claim 5, characterized in that: The first device includes a polarization beam splitter; the second device includes a 90° mixer or a 2×2 coupler; the third device includes a balanced diode or a single diode; and the fourth device includes a transimpedance amplifier.

7. The coherent burst receiving local oscillator laser output power adjustment device according to claim 6, characterized in that: If the receiving end adopts a dual-polarization receiving mode, the first device of the burst coherent receiving component is a polarization beam splitter, the second device is a 90° mixer, the third device is a balanced diode, and the fourth device is a transimpedance amplifier.

8. The coherent burst receiving local oscillator laser output power adjustment device according to claim 6, characterized in that: If the receiving end adopts a single polarization receiving mode, the burst coherent receiving component omits the first device, and the second device is a 2×2 coupler, the third device is a balanced diode, and the fourth device is a transimpedance amplifier.

9. The coherent burst receiving local oscillator laser output power adjustment device according to claim 6, characterized in that: If the receiving end adopts a single-polarization minimalist receiving mode, the burst coherent receiving component omits the first device, and the second device is a 2×2 coupler, the third device is a single diode, and the fourth device is a transimpedance amplifier.

10. An OLT device, characterized in that: The OLT device is provided with a coherent burst receiving local oscillator laser output power adjustment device as claimed in any one of claims 1 to 9.

11. A method for adjusting the output power of a coherent burst receiving local oscillator laser based on the device according to any one of claims 1 to 9, characterized in that: The method comprises the following steps: The burst coherent receiving component receives the burst signal light from different ONUs and the light output by the local oscillator laser, completes the photoelectric conversion and outputs the amplified electrical signal to the burst processing control unit; The burst processing control unit corrects the frequency deviation of the local oscillator laser; and compares the optical power of the corrected signal light and the local oscillator light after mixing with the built-in power high and low threshold values, and outputs the corresponding power control signal to the local oscillator laser and its control unit based on the comparison result and the built-in power and LO bias current relationship table; The local oscillator laser and its control unit adjust the output optical power according to the received power control signal.

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