WO2022237537A1 - 自由空间光通信系统及其功率自适应调节方法 - Google Patents

自由空间光通信系统及其功率自适应调节方法 Download PDF

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Publication number
WO2022237537A1
WO2022237537A1 PCT/CN2022/089504 CN2022089504W WO2022237537A1 WO 2022237537 A1 WO2022237537 A1 WO 2022237537A1 CN 2022089504 W CN2022089504 W CN 2022089504W WO 2022237537 A1 WO2022237537 A1 WO 2022237537A1
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power
communication system
optical
fso communication
fso
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PCT/CN2022/089504
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English (en)
French (fr)
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李汉国
王婧
黄茵
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华为技术有限公司
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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B10/00—Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication
    • H04B10/11—Arrangements specific to free-space transmission, i.e. transmission through air or vacuum
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B10/00—Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication
    • H04B10/40—Transceivers
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B10/00—Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication
    • H04B10/50—Transmitters
    • H04B10/564—Power control

Definitions

  • Various embodiments of the present disclosure relate to the field of optical communication, and more specifically relate to a free space optical (FSO) communication system and a power adaptive adjustment method thereof.
  • FSO free space optical
  • Free Space Optics (FSO) communication is a wireless transmission method based on laser communication, which is equivalent to "invisible optical fiber". Compared with traditional radio frequency wireless technology, it has the advantages of large bandwidth, free spectrum application, and no electromagnetic interference. With the advancement of technology and the optimization of cost, FSO communication has gradually extended from military and inter-satellite communication to civilian ground short-distance communication.
  • the purpose of the present disclosure is to provide an improved Free Optical (FSO) communication system and its power adjustment method, which can provide optimized power adaptive adjustment capability, and can improve the overall throughput of the FSO communication system.
  • FSO Free Optical
  • a power adaptive adjustment method includes: a first free-space optical FSO communication system sends a first optical signal to a second FSO communication system adapted to perform free optical communication with the first FSO communication system with an initial transmission power; the first FSO communication system receiving a second optical signal from the second FSO communication system; the first FSO communication system detects the optical power of the second optical signal as the optical received power of the first FSO communication system; the first FSO communication system An FSO communication system adaptively adjusts the transmit power of the first FSO communication system based on the optical receiving power of the first FSO communication system; and the first FSO communication system sends the adjusted transmit power to the first FSO communication system The second FSO communication system transmits a third optical signal.
  • the first FSO communication system can be used as the active end to use the received optical power of the free optical communication signal from the opposite end as the optical received power of the local end, and realize the optical power of the local end based on the optical received power of the local end.
  • Transmitter power adjustment That is to say, the transmitting power of the local end is realized based on single-ended closed-loop feedback.
  • this can realize the adaptive adjustment of the power of the first FSO system, which advantageously reduces the difficulty of engineering implementation of installation and commissioning, and improves the adaptability of the system to various environments and changes.
  • adaptively adjusting the transmit power of the first FSO communication system includes: in response to the received optical power of the first FSO communication system being lower than a preset power quality threshold, the first FSO communication system Adaptively increase the transmit power of the first FSO communication system.
  • the received optical power is lower than the preset power quality threshold, which means that the free optical communication at both ends does not meet the predetermined communication quality requirements.
  • the quality of free optical communication at both ends can be improved by increasing the transmitting power.
  • adaptively adjusting the transmit power of the first FSO communication system includes: in response to the received optical power of the first FSO communication system being lower than a preset power quality threshold, the first FSO communication system Adaptively increasing the transmitting power of the light emitting device in the first FSO communication system. In these embodiments, increasing the transmit power can be used as one of the main ways to adjust the transmit power.
  • adaptively adjusting the transmit power of the first FSO communication system includes: in response to the received optical power of the first FSO communication system being lower than a preset power quality threshold, the first FSO communication system Adaptively adjust the optical path in the first FSO communication system.
  • the optical path adjustment can reduce the basic loss of the optical path, and therefore can also be used to adjust the transmit power.
  • adaptively adjusting the optical path in the first FSO communication system includes: performing nutation adjustment on optical fiber coupling in the first FSO communication system, so as to improve the coupling efficiency of the optical fiber.
  • the transmitting end power can be adjusted by improving the coupling efficiency of the optical fiber through nutation adjustment.
  • adaptively adjusting the transmitting power of the first FSO communication system further includes: responding to the failure to increase the optical receiving power of the first FSO communication system by means of optical path adjustment, the first FSO communication system An FSO communication system adaptively increases the transmitting power of the light emitting device in the first FSO communication system. In these embodiments, this provides the ability to perform joint adjustments between optical path adjustments and changes in transmit power to change transmit power.
  • adaptively adjusting the transmitting power of the first FSO communication system further includes: in response to the fact that the transmitting power of the optical transmitting device cannot be increased, the first FSO communication system adaptively adjusts the The light receiving sensitivity of the first FSO communication system is adjusted. In these embodiments, this provides the ability to perform joint adjustment between the adjustment of the transmission power and the adjustment of the light receiving sensitivity to adaptively adjust the transmission power.
  • adaptively adjusting the transmit power of the first FSO communication system includes: in response to the received optical power of the first FSO communication system being lower than a preset power quality threshold, the first FSO communication system Adaptively adjust the light receiving sensitivity of the first FSO communication system.
  • the adjustment of the light receiving sensitivity can lead to the change of the light receiving power, and thus can be used as a sub-solution of the adaptive power adjustment power.
  • adaptively adjusting the transmit power of the first FSO communication system includes: in response to the received optical power of the first FSO communication system being lower than a preset power quality threshold, the first FSO communication system Negotiating with the second FSO communication system via free optical communication; and adjusting the light receiving sensitivity of the first FSO communication system based on the negotiation result.
  • the adjustment of the light-receiving sensitivity of both the receiving end and the transmitting end can be realized through negotiation, and in this way, the adjustment of the light-receiving sensitivity can be made more accurate.
  • adaptively adjusting the transmit power of the first FSO communication system includes: in response to the optical received power of the first FSO communication system being lower than a first preset power quality threshold, the first FSO The communication system adaptively switches from low optical receiving sensitivity to high optical receiving sensitivity; or in response to the optical receiving power of the first FSO communication system being higher than a second preset power quality threshold, the first FSO communication system adaptively Switching from high light receiving sensitivity to low light receiving sensitivity, wherein the second preset power quality threshold is greater than the first preset power quality threshold.
  • under the condition of low communication quality switch to high light receiving sensitivity to improve the overall passability of FSO communication; and when the communication link is improved to high communication quality, high light receiving sensitivity can be made Return to low light receiving sensitivity to increase transmission rate.
  • the method further includes: receiving a fourth optical signal from the second FSO communication system after sending the third optical signal with the adjusted transmission power; detecting the optical power of the fourth optical signal to As the updated optical received power of the first FSO communication system; based on the updated optical received power of the first FSO communication system, adaptively adjust the transmit power of the first FSO communication system; and with the adjusted The transmitting power sends a fifth optical signal to the second FSO communication system.
  • the self-adaptive adjustment of the power at the local end is continuously performed dynamically, which includes continuously detecting the received optical power of the local end, and then adjusting the power of the transmitting end based on the updated received optical power. It will be understood that the power adaptive adjustment in these embodiments is performed in conjunction with the power adaptive adjustment of the peer end.
  • adaptively adjusting the transmit power of the first FSO communication system further includes: receiving received optical power information from the second FSO communication system; and based on the received optical power information and the first FSO communication system An optical receiving power of the FSO communication system is adaptively adjusted to transmit power of the first FSO communication system.
  • the transmitting end power can be adjusted based on the optical receiving power of both the local end and the opposite end, which can realize more accurate and rapid adjustment of the transmitting end power.
  • receiving received optical power information from the second FSO communication system comprises: receiving the received optical power information of the second FSO communication system via a link other than an FSO link. Utilizing a link other than the FSO link makes it easier for the first FSO system to receive information fed back from the second FSO communication system, and to make more accurate and rapid adjustments accordingly.
  • a power adaptive adjustment method includes: a second free space optical FSO communication system receiving at a first time a first optical signal from a first FSO communication system adapted for free optical communication with said second FSO communication system; said second FSO communicating The system detects the optical power of the first optical signal as the first optical received power of the second FSO communication system; the second FSO communication system receives the first optical signal from the first FSO communication system at a second time Two optical signals; the second FSO communication system detects the optical power of the second optical signal as the second optical received power of the second FSO communication system; the second FSO communication system is based on the second A comparison result of the received optical power and the first received optical power is used to adaptively adjust the transmitting power of the second FSO communication system.
  • the second FSO communication system also performs power adaptive adjustment based on the received optical power received by the local end.
  • the second FSO communication system usually acts as a slave end and follows the first FSO communication system as an active end to perform adaptive adjustment.
  • a power adaptive adjustment method operating within a communication system, the communication system comprising a first free space optical FSO communication system and a second FSO communication system in free optical communication with each other, the The method includes: the first FSO communication system sends a first optical signal to the second FSO communication system with an initial transmission power; the second FSO communication system detects the optical power of the first optical signal as the The first optical receiving power of the second FSO communication system; the second FSO communication system transmits a second optical signal to the first FSO communication system; the first FSO communication system detects the optical power of the second optical signal , as the second received optical power; the first FSO communication system adaptively adjusts the transmit power of the first FSO communication system based on the second received optical power; the first FSO communication system uses the adjusted transmit a third optical signal to the second FSO communication system; the second FSO communication system detects the optical power of the third optical signal as the third optical receiving power; and based on the third optical As a result of the comparison
  • the power adaptive adjustment method in the third aspect above provides a system-level solution for power adaptive adjustment at both ends of the first FSO communication system and the second FSO communication system.
  • the system-level solution can improve the adaptability of the entire communication system to various environments and changes, especially when the environment is degraded.
  • a first free space optical FSO communication system includes: a transmit port adapted to transmit a first optical signal at an initial transmit power to a second FSO communication system adapted for free optical communication with said first FSO communication system; a receive port adapted to receive a signal from said first FSO communication system The second optical signal of the second FSO communication system; a received optical power detection module, which is adapted to detect the optical power of the second optical signal as the optical received power of the first FSO communication system; and adaptive power An adjustment module, adapted to adaptively adjust the transmitting power of the first FSO communication system based on the optical receiving power of the first FSO communication system; wherein the transmitting port is further adapted to send the adjusted transmitting power to the The second FSO communication system transmits a third optical signal.
  • the adaptive power adjustment module includes: an adaptive transmit power adjustment module, which is adapted to adaptively adjust when the received optical power of the first FSO communication system is lower than a preset power quality threshold The transmitting power of the optical transmitting device in the first FSO communication system;
  • the adaptive power adjustment module includes: an optical path adjustment module, which is adapted to communicate with the first FSO when the received optical power of the first FSO communication system is lower than a preset power quality threshold The optical path within the system is adjusted.
  • the optical path adjustment module further includes a nutating module, and the nutating module is adapted to control the first The fiber coupling in the FSO communication system is nutated to improve the efficiency of the fiber coupling.
  • the adaptive power adjustment module includes: a sensitivity adaptive adjustment module, the sensitivity adaptive adjustment module is adapted to when the optical received power of the first FSO communication system is lower than a preset power quality threshold , adaptively adjusting the light receiving sensitivity of the first FSO communication system.
  • adaptively adjusting the transmitting power of the first FSO communication system includes: in response to the optical receiving power of the first FSO communication system being lower than a preset power quality threshold, the adaptive power adjustment module Adaptively increase the transmit power of the first FSO communication system.
  • the sensitivity adaptive adjustment module further includes: a negotiation module, adapted to adaptively via The free optical communication negotiates with the second FSO communication system to determine the light receiving sensitivity of the first FSO communication system; the switching module is adapted to determine the light receiving sensitivity based on the negotiated light receiving sensitivity of the first FSO communication system Switches between different light receiving sensitivities.
  • the adaptive power adjustment module is further configured to: in response to the received optical power of the first FSO communication system being lower than a preset power quality threshold, first use the optical path adjustment module to adjust the first The optical path in the FSO communication system is adjusted; in response to the adjustment of the optical path, the transmitting power of the first FSO communication system cannot be increased, and the adaptive transmission power adjustment module is used to adaptively increase the first FSO communication system The transmitting power of the light emitting device; and in response to the fact that the transmitting power of the light emitting device cannot be increased, a sensitivity adaptive adjustment module is used to adaptively adjust the light receiving sensitivity of the first FSO communication system.
  • the communication system further includes: a management channel, the first FSO communication system is adapted to receive the communication from the second FSO communication system via the management channel through a communication link other than free optical communication Received optical power information, the adaptive power adjustment module is adapted to adaptively adjust the transmitting power of the first FSO communication system based on both the received optical power information and the optical received power of the first FSO communication system .
  • a second free space optical FSO communication system includes a receive port adapted to receive a first optical signal from a first FSO communication system adapted for free optical communication with said second FSO communication system at a first time, and a second time after the first time Two times receive the second optical signal from the first FSO communication system; receive optical power detection module, which is adapted to detect the optical power of the first optical signal as the first optical signal of the second FSO communication system receiving power, and detecting the optical power of the second optical signal as the second optical receiving power of the second FSO communication system; an adaptive power adjustment module, which is adapted to be based on the second optical receiving power and the Adaptively adjust the transmit power of the second FSO communication system according to the comparison result of the first optical received power; the transmit port is adapted to transmit an optical signal to the first FSO communication system with the adjusted transmit power.
  • a communication system includes the first free space optical FSO communication system according to the fourth aspect and the second FSO communication system according to the fifth aspect, which perform free optical communication with each other.
  • the communication systems of the fourth, fifth and sixth aspects above may correspond to the communication systems of the first, second and third aspects above, and obtain technical effects corresponding thereto.
  • FIG. 1A shows a schematic arrangement of a conventional split FSO communication system.
  • FIG. 1B shows a schematic arrangement of a conventional integrated FSO communication system.
  • FIG. 2A shows an exemplary arrangement of a power adaptive adjustment scheme of an optical emitting device based on single-ended closed-loop feedback according to an exemplary embodiment of the present disclosure.
  • Fig. 2B shows an example of the corresponding relationship between various power quality thresholds and communication quality according to an example embodiment of the present disclosure.
  • FIG. 3 shows an exemplary arrangement of an architecture-level systematic automatic joint debugging solution based on single-ended closed-loop feedback according to an exemplary embodiment of the present disclosure.
  • Fig. 4A shows a schematic flowchart of the three-link joint debugging concept according to an example embodiment of the present disclosure.
  • Fig. 4B shows a schematic flowchart of a specific example of three-step joint debugging according to an exemplary embodiment of the present disclosure.
  • FIG. 5 shows an exemplary arrangement of a sensitivity adaptive adjustment sub-scheme based on single-ended closed-loop feedback according to an exemplary embodiment of the present disclosure.
  • 6A to 6C illustrate exemplary arrangements of adaptive FSO optical path adjustment sub-schemes based on power feedback across devices/modules within a single end according to example embodiments of the present disclosure.
  • Fig. 7 shows an exemplary arrangement of an adaptive FSO nutation adjustment sub-scheme based on power feedback across devices/modules within a single end according to an example embodiment of the present disclosure.
  • Fig. 8 shows an exemplary arrangement of a power adaptive adjustment scheme of an optical transmitting device based on peer-end power feedback according to an exemplary embodiment of the present disclosure.
  • FIG. 9 shows an exemplary arrangement of an architecture-level systematic automatic joint debugging scheme based on dual-terminal power feedback according to an exemplary embodiment of the present disclosure.
  • Fig. 10 shows an exemplary arrangement of a scheme for adaptive adjustment of sensitivity based on local power feedback (without a negotiation module) according to an exemplary embodiment of the present disclosure.
  • FIG. 11 shows a flowchart of a power adaptive adjustment method operating within a free space optical (FSO) communication system according to an example embodiment of the present disclosure.
  • FSO free space optical
  • Fig. 12 shows a flow chart of a power adaptive adjustment method for operation in a free space optical (FSO) communication system according to another example embodiment of the present disclosure.
  • Fig. 13 shows a flow chart of a power adaptive adjustment method operating in a free space optical (FSO) communication system according to yet another exemplary embodiment of the present disclosure.
  • FSO free space optical
  • FIG. 1A shows a schematic arrangement of a conventional split FSO communication system.
  • the communication light usually laser
  • the FSO equipment is only used as light transmission, that is, the communication light is received from the network equipment through the optical fiber connection, and the communication light passes through the FSO
  • the FSO communication system is directly sent to another FSO communication system as the opposite end (in this example, it is also a split FSO communication system, but this is not a limitation, and the other FSO communication system can also be as shown in Figure 1B below integrated FSO communication system).
  • the above-mentioned FSO equipment will not change the optical signal, but only adjust the beam expansion/convergence, optical path, etc. of the light; after the peer FSO equipment receives the communication light, it is coupled into the optical fiber after the internal transmission of the FSO equipment, and then connected to the optical fiber through the optical fiber.
  • Network equipment is not change the optical signal, but only adjust the beam expansion/convergence, optical path, etc.
  • a conventional FSO device may include the following components: lens assembly, coarse tracking and fine tracking actuators, power detection module, calculation module, beacon light, etc.
  • beacon lights and coarse tracking actuators are optional. These components are briefly introduced below.
  • the lens component is usually a lens group, which is mainly used to achieve optical beam expansion, light splitting and other functions; it can also use a specially designed single lens, or a device that can achieve the same lens function, such as LCoS (Liquid Crystal on Silicon, silicon-based liquid crystal).
  • LCoS Liquid Crystal on Silicon, silicon-based liquid crystal
  • the beacon light is mainly used for the preliminary alignment of the equipment at both ends, and can work with the coarse tracking actuator.
  • the beacon light may be a visible laser.
  • the power detection module is mainly used to detect the received communication light and beacon light (sent from the opposite end), and is coupled to the calculation module.
  • the power detection can use the lens assembly to guide a small part of the optical signal through the beam splitter for detection.
  • a small part of the optical signal may be derived for detection by using an optical splitting device.
  • the power detection module may be a photodetector.
  • the calculation module can perform corresponding calculation functions, such as determining whether the quality of free optical communication meets the requirements, so that the calculation results can be used to drive the rough tracking and fine tracking actuators.
  • the power detection modules of the coarse tracking and the fine tracking may be the same or different, which is not limited here.
  • the computing module may be a chip, a circuit board, or the like.
  • Coarse tracking and fine tracking actuators are mainly used for large-scale alignment of equipment, such as alignment of equipment during installation, calibration of large deviations caused by gravity and other effects after long-term use of equipment, etc.; fine tracking The actuator is mainly used to cope with optical path deviation calibration caused by jitter (such as atmospheric disturbance, etc.).
  • the coarse tracking execution structure can perform coarse adjustment on the whole of the components in the dotted box.
  • the rough tracking execution structure may be a specific device such as a pan/tilt;
  • the fine tracking execution mechanism may be a micro-electromechanical system (MEMS), a voice coil motor, and the like.
  • MEMS micro-electromechanical system
  • Light emitting and receiving holes used for sending and receiving communication light of FSO equipment.
  • Optical fiber interface used to connect to network devices.
  • a nutating module can also be included in the connection section between the optical fiber coupling and the optical fiber interface, and the nutating module can adjust the optical fiber coupling according to the received optical power to improve the optical fiber
  • the coupling efficiency of which is especially useful for the case where the coupling fiber is a single-mode fiber.
  • Coarse adjustment stage In the coarse adjustment stage, the beacon light can be used, and the power detection module can detect the received power intensity of the beacon light to drive the coarse tracking actuator to adjust, and roughly align the devices at both ends.
  • the specific implementation It can be performed manually, manually+automatically or fully automatically, and there is no limitation here. It should be noted that some systems may use a non-power detection method to observe the beacon light. Since this is not the focus of the present invention, they are not listed one by one and are not limited.
  • Fine adjustment stage using communication light, the power detection module detects the received power intensity of the communication light, drives the fine tracking actuator to adjust, and realizes the precise alignment of the optical paths of the equipment at both ends, so that the optical power received by the equipment at both ends reaches a good level state.
  • FIG 1B shows a conventional all-in-one FSO communication system.
  • the difference between the integrated FSO communication system and the split FSO communication system is that in the integrated FSO communication system, the "network equipment” and “FSO equipment” in Figure 1A are respectively represented by “network module” and “FSO equipment” in Figure 1B modules” and the fiber optic coupling therein can be realized without a fiber optic interface.
  • the integrated FSO communication system is similar to the split FSO communication system, so details will not be repeated here. It will be understood that both “network device” and “network module” are similar in structure and function, and both "FSO device” and “FSO module” are similar in structure and function.
  • network device and “network module” can be used interchangeably
  • FSO device and “FSO module” can be used interchangeably , unless it is specifically specified in the text that it is used for a split FSO communication system or an integrated FSO communication system.
  • the passability rate is an important indicator to measure the performance of the FSO communication system. Referred to as "light receiving sensitivity”) correlation.
  • light receiving sensitivity correlation
  • ⁇ Link insertion loss It is related to the accuracy of optical path calibration or nutation adjustment of FSO equipment/modules, devices, and environmental disturbances. Among them, the optical path calibration or nutation adjustment of the FSO device/module is a technically controllable part, which is the focus of this disclosure. The higher the accuracy of optical path calibration or nutation adjustment, the smaller the link insertion loss, and the higher the power margin of the FSO communication system, the more favorable it is to the passability.
  • ⁇ Transmitting power set the driving power of the optical transmitting device in the network device connected with the FSO device or the network module of the integrated FSO communication system.
  • the transmitting power will affect the receiving power of the opposite end. Under the same link insertion loss and receiving end sensitivity conditions, the greater the transmitting power, the higher the receiving power of the opposite end, and the more favorable the communication rate (the receiving power is not higher than that of the network equipment. / module can receive the upper limit as the premise).
  • Optical receiving sensitivity It is determined by the receiving optical module of the network device or module. The higher the receiving sensitivity, the larger the dynamic range of the communication system, and the more favorable the throughput rate. It should be noted that, in general, the higher the receiving sensitivity of the optical module, the lower the rate may be.
  • ⁇ Transmitting power It is defined by the power of the optical signal transmitted by the FSO communication system to the outside.
  • the above-mentioned link insertion loss, transmitting power and light receiving sensitivity change or difference can change the transmitting power.
  • Solution 1 is to set and fix the transmission power of the network equipment or module (or the driving power of the optical transmitting device) during installation. Generally, it cannot be adjusted adaptively later. At this time, the transmission power is determined by the transmission power or the driving power.
  • the disadvantage of the first solution is that, unlike optical fibers, the quality of FSO space links is affected by the atmospheric environment, so the problem of this type of system is that constant optical power is difficult to cope with complex and variable actual application environments with uncertain fluctuations. On the one hand, different environments have different requirements for the input power of the light source; on the other hand, when the atmospheric environment deteriorates, if the transmit power cannot be increased in time, the link quality may drop significantly (a large number of packet loss, disconnection, etc.), affecting the link pass rate.
  • Solution 2 Links other than free optical communication are added as management channels to feed back the receiving power of the opposite end, such as Wi-Fi, mobile networks, etc.
  • This solution can improve the problem that solution 1 cannot adaptively adjust the power of the transmitting end.
  • the optical receiving power information of the opposite end can be obtained through the management channel, and the optical receiving power of the opposite end can be used as the judgment basis to automatically adjust the transmitting power of the local end, so as to realize the adaptive adjustment of the transmitting end power based on the receiving end receiving power feedback.
  • the disadvantage of the second scheme is that it needs to increase the link outside the communication as a management channel, but the area where the FSO communication system needs to be deployed is often inconvenient to deploy other communication schemes (such as radio frequency schemes with electromagnetic interference, requiring cable laying cable communication scheme, etc.), so the application of the scheme has limitations.
  • this type of scheme only adjusts the transmission power adaptively, but the communication rate of the FSO communication system is related to multiple factors. When the transmission power is adjusted to the limit, if the received power at the receiving end still cannot meet the requirements, the link quality will still be faced. Issues that cannot be guaranteed.
  • FSO equipment and network equipment are often simply connected, so there are some similar functional module design redundancy problems between the two. It is obvious that network equipment often has power detection functions. If it can be used for FSO If the power detection requirements of the device are met, the FSO device can save the power detection module.
  • the purpose of the present disclosure is at least to solve or alleviate the following problems in the conventional FSO communication system, namely: the adaptive power adjustment of the conventional FSO communication system requires an additional management link; or the FSO communication system lacks automatic joint debugging at the architecture level ——The three links of FSO equipment optical path calibration/nutation adjustment, transmission power adjustment, and optical receiving sensitivity adjustment lack linkage—the anti-disturbance ability cannot be fully utilized, and the overall throughput rate needs to be improved, etc.
  • First implementation mode power adaptive adjustment scheme without additional management channel (or without additional communication link)
  • the solution of the first embodiment is based on a power adaptive adjustment scheme without additional management channel (or no additional communication link), and the term "no additional management channel/no additional communication link" means that there is no Additional management channels/links other than the management channels/links, these additional management channels (or no additional communication links) can be realized through WIFI, mobile network, Bluetooth, Zigbee and other technologies, for example.
  • This first embodiment may include multiple examples as follows. It will be understood that these multiple embodiments can be combined arbitrarily under the condition of not contradicting each other, and the solutions of these combinations are all within the spirit and protection scope of the present disclosure.
  • Embodiment 1 Adaptive Adjustment Scheme of Transmitting Power Based on Single-Ended Closed-loop Feedback
  • its transmission power adaptive adjustment scheme is completely based on single-ended closed-loop feedback.
  • the transmitting power of the end is adjusted without depending on the optical receiving power signal from the opposite end.
  • the space link of the FSO communication system has the following characteristics: when the space link is affected by external factors such as weather, the received optical power at both ends increases and decreases at the same time, which is symmetrical.
  • the idea of this embodiment is to evaluate or estimate the received power of the opposite end through the received optical power of the local end, thereby driving the adjustment of the transmit power of the local end, thereby realizing the adaptive transmit power adjustment of the link without additional management.
  • two FSO communication systems that communicate with each other can be divided into a master end 10 and a slave end 20, where the master end 10 is the end that initiates power adjustment at the sender end first, and the slave end 20 is the other end that follows the adjustment .
  • the FSO communication system on the left is the master end 10
  • the FSO communication system on the right is the slave end 20 .
  • this division does not constitute any limitation on the FSO communication system.
  • the configurations of the driving end 10 and the driven end 20 may be completely the same or different. Merely as an example, as shown in FIG. 2A , the configurations of the driving end 10 and the driven end 20 are the same.
  • the active end 10 may include a sending port 101, a receiving port 104, a receiving optical power detection module 103, and an adaptive transmitting power adjustment module 102; and the slave end 20 may also include a sending port 201, a receiving port 204, a receiving optical power A power detection module 203 and an adaptive transmit power adjustment module 202 .
  • the above received optical power detection modules 103, 203 may be, for example, photodetectors, and may be integrated in, for example, an optical module; the adaptive transmission power adjustment modules 102, 202 may be, for example, a driving circuit, a driving chip, etc. of an optical emitting device .
  • the transmit port, receive port, received optical power detection module and adaptive transmit power adjustment module are all arranged in the network device/module 100 or 200 indicated in the dotted line box, but This is just an example, which does not constitute any limitation on the arrangement positions of the transmitting port, the receiving port, the receiving optical power detection module and the adaptive transmitting power adjustment module in the master end/slave end. It should also be understood that, in other embodiments, any end of the two FSO communication systems that perform free optical communication with each other may serve as the master end, and the other end serves as the slave end.
  • the self-adaptive adjustment process of the transmit power based on the single-end closed-loop feedback can be realized, for example, by adjusting the transmit power of the optical transmit device in the active end.
  • the specific process is as follows:
  • the active end 10 can send an optical communication signal to the slave end 20 via the sending port 101 with the initial sending power, and then the receiving port 104 can receive the optical communication signal from the slave end 20 .
  • the received optical power detection module 103 can detect the optical power of the received optical signal and provide it to the adaptive transmission power adjustment module 102 synchronously. It will be understood that the received optical power detected by the active end 10 is the optical received power of the active end.
  • the adaptive transmit power adjustment module 102 can adaptively adjust the transmit power of the optical transmit device in the active end based on the received optical power received by the active end, so as to adjust the transmit power of the active end 10 .
  • the adaptive transmitting power adjustment module 102 can use it to Evaluate the free optical communication quality between the active end 10 and the driven end 20, and can adaptively adjust (for example, increase or decrease) the transmission power of the light emitting device in the active end according to the evaluated free optical communication quality, In this way, the transmitting power of the active end is adaptively adjusted.
  • evaluating the free optical communication quality based on the received optical power of the active end may include: comparing the received optical power of the active end 10 with a preset power quality threshold.
  • the preset power quality threshold may include, for example, a first power quality threshold, a second power quality threshold, a third power quality threshold, and a fourth power quality threshold. These thresholds may be related to different communication The quality corresponds.
  • the first power quality threshold may be a power threshold for ensuring normal communication quality
  • the second power quality threshold may be a power threshold indicating that basic communication (low-quality communication) cannot be performed
  • the third power quality threshold may be a power threshold for ensuring high-quality communication.
  • the fourth power threshold may be a power threshold indicating that the received optical power is too high.
  • the preset power quality threshold may include more or less different power quality thresholds.
  • these power quality thresholds may vary with different environmental conditions (eg, different environmental or climatic conditions, including hazy, foggy, rainy, or sandy weather). In some embodiments, these different power quality thresholds can be set according to experience of those skilled in the art.
  • the aforementioned adaptively adjusting the power of the light-emitting device in the active end may include increasing, decreasing, or keeping the transmit power of the light-emitting device in the active end unchanged.
  • the above-mentioned method of adaptively adjusting the transmitting power of the optical transmitting device is only one way of adjusting the power of the transmitting end, and other ways of adjusting the power of the transmitting end may also include but are not limited to: calibrating the optical path in the active end or Adjust and adjust the light receiving sensitivity in the active end. .
  • the adaptive calibration or adjustment of the optical path in the active end may include: adjusting or calibrating the optical path in the FSO device/module based on the received optical power received at the active end, which can be achieved, for example, through the The coarse tracking actuator or the fine tracking actuator shown in , adjusts the optical path in the active end (the optical path includes an optical component disposed thereon, such as a lens assembly), and/or adjusts the nutating module in the active end to Realization, wherein the adjustment of the nutating module in the active end can improve the coupling efficiency of the optical fiber.
  • adjusting the optical path or “calibrating the optical path” can be considered to have the same meaning, and they can be used interchangeably.
  • adjusting the light receiving sensitivity in the active end may include: adjusting the light receiving sensitivity of the active end based on the received light receiving power at the active end.
  • multiple light-receiving sensitivity modules may be provided in the active end for switching by the active end.
  • the adaptive transmit power adjustment module 102 described above may exist as a part of a broader adaptive power adjustment module.
  • the adaptive power adjustment module may also include an adaptive optical path adjustment module (for example, it may include a coarse/fine tracking actuator), and a sensitivity adaptive adjustment module (for example, it may be composed of an optical module), as will be described later will be described further.
  • the adaptive transmit power adjustment module 102 adaptively adjusts the transmit power of the active end 10
  • the active end 10 can use the adjusted The power of the transmitting end sends an optical signal with the adjusted power to the slave end 10 .
  • the power adaptive adjustment process of the slave side based on single-ended closed-loop feedback is as follows:
  • the slave end 20 can receive the optical signal from the active end 10 via the receiving port 201, and detect the optical power of the optical signal as the optical receiving power of the slave end via the received optical power detection module 202, and synchronize it to the adaptive transmit power adjustment module 203.
  • the optical power detection module 202 will always detect the optical signal from the active end.
  • the adaptive transmit power adjustment module 203 determines that the optical receiving power at the slave end 20 changes, it can be determined that the master end 10 has completed the adjustment of the transmit end power. Subsequently, the slave end 20 can adaptively adjust the transmit power of the slave end 20 according to the change of the received light power of the local end.
  • the aforementioned adaptively adjusting the transmitting power of the slave end 20 may include increasing, decreasing, or keeping the transmitting power of the slave end unchanged.
  • the above-mentioned method of adaptively adjusting the transmitting power of the slave end may include but not limited to: adaptively adjust the transmit power of the optical transmitting device at the slave end, calibrate or adjust the optical path in the slave end, and adjust the power of the slave end Adjust the light-receiving sensitivity in the moving end.
  • calibrating or adjusting the optical path in the driven end may include: adjusting the optical path in the driven end (the optical path includes setting The optical components on it, such as lens components) are adjusted or calibrated, and the nutating module in the active end is adjusted to improve the coupling efficiency of the optical fiber.
  • the power adaptive adjustment of the active end or the slave end is based on the detected optical received power of the local end. It does not depend on the received optical power fed back by the peer. Therefore, in these embodiments, additional management links (eg, WIFI, mobile network, etc.) may be omitted.
  • additional management links eg, WIFI, mobile network, etc.
  • Example 2 Architecture-level systematic automatic joint debugging scheme based on single-ended closed-loop feedback
  • Embodiment 2 is also based on single-ended closed-loop feedback, and the received power at the local end is used as the basis for judging the quality of free optical communication, but different from Embodiment 1, Embodiment 2 can at least The following three links carry out automatic linkage adjustment: a) self-adaptive adjustment of the transmission power of the optical transmitting device at the active end/slave end, b) calibration or adjustment of the optical path in the active end/slave end (which includes adjusting the optical fiber The coupling is adjusted by nutation), c) the light receiving sensitivity in the driving end/slave end is adjusted.
  • Figure 3 shows the architecture-level systematic automatic joint debugging based on single-ended closed-loop feedback.
  • the active terminal 10 is used for description here. It will be appreciated that the configuration of the slave end may be the same as or different from the master end.
  • the active end 10 shows a network device/module 100 and an FSO device/module 150 .
  • the network device/module 120 may further include a sensitivity adaptive adjustment module 105 in addition to the transmission port 101, the reception port 104, the received optical power detection module 103 and the adaptive transmission power adjustment module 102.
  • the adaptive adjustment module 105 may be based on the received optical power detected by the received optical power detection module 103 (it may, for example, be compared with a preset power quality threshold to evaluate the free optical communication quality between the master end and the slave end) And adaptively adjust the light receiving sensitivity of the active end.
  • the FSO device/module 150 may include an optical path adjustment module 151 , and the optical path adjustment module 151 may also adaptively adjust the optical path in the active end based on the received optical power detected by the received optical power detection module 103 .
  • the optical path adjustment module 151 may include a nutating module, so as to perform optical fiber coupling in the active end 10 (for example, optical fiber coupling between the network device/module and the FSO device/module 150). Nutating adjustments to improve fiber coupling efficiency.
  • the adaptive adjustment of the transmit power can be further optimized.
  • the three links a)-c) described above can be linked, so as to realize the automatic joint debugging of these three links. In this way, the adaptive ability of the FSO communication system under different environmental conditions can be improved, and the overall availability of the system can be improved.
  • the received optical power detection module 103 of the network device/module at the active end can detect the received optical power, and feed back the power situation to the optical path adjustment module 151 (see FIG. 3 ) of the FSO device/module, and the optical path adjustment module 151 can Free light is evaluated in terms of light received power (which can be compared, for example, with a preset power quality threshold (which can be, for example, the first power quality threshold, the second power quality threshold, or the third power quality threshold in FIG. 2B above).
  • a preset power quality threshold which can be, for example, the first power quality threshold, the second power quality threshold, or the third power quality threshold in FIG. 2B above).
  • the optical path/nutation of the FSO equipment/module in the active end can be adjusted preferentially.
  • the optical path adjustment module 151 can include the coarse/nutation described above. Fine tracking actuator and nutation module, so that optical path calibration/nutation adjustment can be performed. The slave end will follow and adjust. After (repeatedly) performing optical path calibration/nutation adjustment, the optical receiving optical power at the active end may reach The optimal value of this adjustment stage, at this time, the optical receiving power will be stable within a certain range and cannot be increased.
  • the active end can continue to detect the optical received power, and judge whether the preset power quality threshold has been reached, if not, then the adaptive transmit power adjustment module 102 in FIG. 3 can be used to adjust the power of the local end.
  • the transmitting power of the optical transmitting device changes the receiving power of the driven end; the driven end also drives the adjustment of the transmitting power of the optical transmitting device in it due to the adjustment and change of the received optical power. And when the received optical power obviously exceeds the power required for communication with the desired quality, the transmit power of the active end or the slave end can be reduced.
  • the active end can continue to detect the optical receiving power until the transmitting power of the optical transmitting device in the active end has been adjusted to the maximum, which still cannot meet the predetermined communication quality power requirements, which indicates that the link status is relatively
  • increasing the light receiving sensitivity may lead to a decrease in the rate, this can guarantee the predetermined communication quality of the link or it can still be communicated.
  • the above light receiving sensitivity can be adjusted by the sensitivity adaptive adjustment module 105 in FIG. 3 , for example.
  • joint debugging of these three links is described above in the order of 1) ⁇ 2) ⁇ 3), it should be understood that this is just an example. In other embodiments, it is also possible to implement the joint debugging of these three links in other orders. In some other embodiments, it is possible to realize the joint debugging of more links or fewer links that can adjust the power of the transmitting end. In some other embodiments, power adaptive adjustment can be performed only for one link.
  • FIG. 4B shows a more detailed flow chart of an example embodiment of systematic automatic joint adjustment.
  • the power detection of the received optical power at the receiving end can be performed, and then the free optical communication quality can be evaluated according to the received optical received power (which can be compared with the first power quality threshold, for example).
  • the received optical power does not reach the power threshold of normal communication quality (for example, the first power quality threshold)
  • the optical path/nutation of the FSO device/module in the active end is preferentially adjusted.
  • the detection of the received light power can be continued at block 412. If at block 413, it is found that the received light power can continue to increase, then return to block 411 to continue the optical path/nutation adjustment of the FSO device/module, otherwise at block 414, Adjust the transmission power of the receiving end and the sending end.
  • block 415 continue to detect the optical received power, and in block 416, judge whether the optical received power exceeds the normal communication power quality threshold (such as the first power quality threshold), if not, then in block 419, judge whether the transmission Whether the power has been adjusted to the maximum value; if so, then at block 417, it is judged whether the received light power exceeds the power threshold (for example, the third power quality threshold) for high-quality communication. Once it does not exceed, for example, the third power quality threshold, then return to block 414 to continue the adjustment of the transmit power, such as further increasing the transmit power; quality threshold). If yes, return to block 414 to adjust the transmission power, for example, reduce the transmission power.
  • the normal communication power quality threshold such as the first power quality threshold
  • block 419 If in block 419 it is determined that the transmit power is not adjusted to the maximum value, then return to block 414 to further increase the transmit power. On the contrary, if at block 419, once it is determined that the transmit power has been adjusted to the maximum value, then at block 420, it is further determined whether the received optical power reaches a power threshold (such as the second power quality threshold) that cannot guarantee basic communication. If yes, then in block 421, adjust the optical module, that is, adjust the sensitivity, for example, adjust from low light receiving sensitivity to high light receiving sensitivity.
  • a power threshold such as the second power quality threshold
  • frame 422 continue to carry out the detection of receiving optical power, and in frame 423, judge whether optical receiving power returns to the power threshold (such as the first power quality threshold) of normal communication, if not, then return frame 421, further carry out optical Adjustment of the module (or sensitivity), for example, the sensitivity can be further increased (if possible).
  • the power threshold such as the first power quality threshold
  • the received optical power can be selectively further determined. Whether it exceeds the power threshold (for example, the third power quality threshold) for high-quality communication, and if so, return to block 421 to adjust the optical module (or sensitivity), for example, adjust back to low light receiving sensitivity.
  • power adaptive adjustment may be performed based on more or fewer power quality thresholds; or , the adaptive adjustment of power may be performed in a manner different from the combined power quality threshold shown in FIG. 4B .
  • Embodiment 3 Sensitivity adaptive adjustment sub-scheme based on single-ended closed-loop feedback
  • Embodiment 3 may be a sub-solution of the sensitivity adaptive adjustment in Embodiments 1 and 2.
  • this sub-solution can switch the optical module to ensure the link when the received optical power is severely degraded. It is still available; and when the environmental conditions recover, switch back to the original module.
  • the two-terminal FSO communication system can be divided into a master end and a slave end.
  • the master end first adjusts the optical module, and the slave end follows the adjustment according to the change of the master end.
  • FIG. 5 shows an exemplary architectural arrangement of this Embodiment 3.
  • the aforementioned sensitivity adaptive adjustment module 105 may include a sensitivity adaptive receiving (or sending) module.
  • the sensitivity adaptive receiving (or sending) modules 107, 106 may further include a high-sensitivity and low-sensitivity receiving (or sending) module 111, a switching module 108, a negotiation module 109, and an optical module adaptive adjustment module 110; in the slave end, the sensitivity adaptive receiving (or sending) modules 207 and 206 may include a high-sensitivity and low-sensitivity receiving (or sending) module 211, a switching module 208, a negotiation module 209 and an optical module adaptive adjustment module 210 .
  • the sensitivity adaptive receiving (or sending) modules 107 , 106 in the active end 10 may be the same as or different from the sensitivity adaptive receiving (or sending) modules 207 , 206 in the slave end 20 .
  • the optical module adaptive adjustment module 110 is adapted to receive the received optical power detected by the received optical power detection module 103, and is adapted based on the received optical power (for example, thereby evaluating the quality of free optical communication), and Adaptively switch between the high-sensitivity and low-sensitivity receiving modules 111 via the switching module 109 to thereby adjust the light receiving sensitivity, thereby adjusting the transmitting power of the active end.
  • the high- and low-sensitivity optical receiving (or transmitting) modules 107, 106 or 207, 206 can be packaged by two independent modules, or can be a hardware module to adjust the sensitivity by adjusting the algorithm level such as coding, and at the same time It can be any optical module with a sensitivity adjustable function, and the implementation method is not limited here.
  • the sensitivity grades of the optical modules are not limited to two, and may be more.
  • the active end 10 detects the received optical power, and when the power is less than a predetermined quality communication power threshold (for example, a first power quality threshold that guarantees normal communication, or a second power quality threshold that can only guarantee basic communication (or low-quality communication), or When the third power quality threshold for high-quality communication is ensured), the optical module adaptive adjustment module 110 in the sensitivity adaptive adjustment module can drive the receiving module of the local end to switch from low sensitivity to high sensitivity through the switching module 108, for example, from low sensitivity receiving The module switches to a high-sensitivity receiving module.
  • a predetermined quality communication power threshold for example, a first power quality threshold that guarantees normal communication, or a second power quality threshold that can only guarantee basic communication (or low-quality communication)
  • the optical module adaptive adjustment module 110 in the sensitivity adaptive adjustment module can drive the receiving module of the local end to switch from low sensitivity to high sensitivity through the switching module 108, for example, from low sensitivity receiving The module switches to a high-sensitivity receiving module.
  • the sensitivity adaptive sending module 206 of the slave end 20 and the sensitivity adaptive receiving module 107 of the active end can negotiate through the negotiation modules 109 and 209, and follow and switch the sensitivity.
  • the received optical power detection module 103 continuously detects the received optical power. In some embodiments, when it is found that the received optical power returns to a higher level (there is still high-quality communication under the condition that the sensitivity of the receiving module is relatively low), both ends
  • the callback mechanism can be started to switch back from the high-sensitivity receiving (sending) module to the low-sensitivity receiving (sending) module.
  • Embodiment 4 Adaptive FSO optical path/nutation calibration sub-scheme based on single-ended cross-device/module power feedback
  • the FSO optical path/nutation calibration needs to be performed through the optical receiving power.
  • an FSO communication system especially a split FSO communication system
  • both the network device/module and the FSO device/module often have a receiving power detection function, and there is a problem of design redundancy.
  • the received optical power detection module 103 of the network device/module or the received optical power detection module (not marked) of the FSO device/module can be multiplexed to feed back the detected optical power to the FSO device/module
  • the coarse/fine tracking actuator or nutating module in the module adjusts the optical path or nutating.
  • this sub-solution focuses on the received optical power detection module, and does not limit the integration of the calculation module.
  • This calculation module can be used as the aforementioned adaptive transmission power adjustment module 102 and sensitivity adaptive adjustment module 105 , or the optical path adjustment module 151 or constitute a part of these modules 102 , 105 , 151 .
  • the computing module may exist independently of these modules 102 , 105 , 151 , but provide additional computing functions to these modules 102 , 105 , 151 .
  • FIG. 6A shows that in the case where the received optical power detection module 103 of the network device/module 100 is multiplexed, the calculation module 215 can be built in the arrangement of the FSO device/module 200;
  • FIG. 6B shows that in the network device In the case of multiplexing the received optical power detection module 103 of the /module 100, the calculation module 215 can be built into the arrangement in the network device/module 100;
  • FIG. 6C shows the received optical power detection module 103 in the network device/module 100 In the case of multiplexing, the computing module 215 can be placed externally in the arrangement of both the FSO device/module 200 and the network device/module 100 .
  • the calculation module 215 combined with the coarse/fine tracking execution structure may constitute the aforementioned adaptive power adjustment module, such as an optical path adjustment module.
  • the aforementioned adaptive power adjustment module such as an optical path adjustment module.
  • FIG. 7 in the case of multiplexing of the received optical power detection module 103 of the network device/module 100, its optical detection power is fed back to the arrangement of the nutating module 216, wherein the nutating module 216 can also be regarded as the aforementioned and an adaptive power adjustment module, such as an optical path adjustment module or a part of the optical path adjustment module.
  • the transmit power adjustment of the local optical transmitting device without additional management channel is realized based on the received power feedback (single-ended closed-loop feedback) of the local end (for example, the active end), Light receiving sensitivity adjustment or FSO optical path/nutation adjustment, and automatic joint adjustment of three links can be realized at the same time.
  • follow-up adjustment of the opposite end for example, the driven end
  • Embodiments 5-8 a related technology of implementing adaptive transmission power adjustment by using an additional management channel will be described.
  • Second implementation mode power adaptive adjustment scheme based on additional management channels
  • This second embodiment differs from the previous first embodiment in that in this embodiment there is an additional management channel. It can be understood that the second embodiment is a modified embodiment of the first embodiment with an additional management channel. Therefore, the above description about the first embodiment can be applied to the second embodiment without conflicting with each other. Likewise, the second embodiment may have multiple embodiments. In the case of not contradicting each other, these embodiments can also be combined arbitrarily, and can be combined with the embodiments in the first embodiment, and their combinations are within the spirit and scope of the present disclosure. Various examples of the second embodiment are described
  • Embodiment 5 Power Adaptive Adjustment Scheme Based on Peer Power Feedback
  • Embodiment 5 Compared with Embodiment 1, the difference of this Embodiment 5 is that: the adaptive adjustment of the transmit power of the FSO system at both ends of the FSO link can be performed based on the received optical power of the opposite end, wherein the opposite end can pass the optical received power status through the management channel Synchronize to the local end.
  • Fig. 8 shows a schematic arrangement of a power adaptive adjustment scheme based on peer power feedback.
  • FIG. 8 shows a network device/module 100 in the FSO communication system as the local end and a network device/module 200 in another FSO communication system as the opposite end.
  • the network device/module 100 in FIG. 8 may include a sending port 101, a receiving port 104, an adaptive adjustment optical power module 102, a receiving optical power acquisition module 122 and a management channel 121, wherein the receiving optical power acquisition module 122
  • the received power detection module of the local end and the received power synchronization module for the opposite end are integrated, and the latter can obtain the received power information of the opposite end through the management channel.
  • the adjustment of the transmitting power of the local end may be performed only based on the optical receiving power of the peer end.
  • the adjustment of the transmitting power of the optical transmitting device at the local end may be performed by means of both the received optical power of the local end and the received optical power of the remote end.
  • Embodiment 6 Architecture-level systematic automatic joint debugging scheme based on dual-terminal power feedback
  • the automatic joint debugging scheme of this embodiment 6 is different from the automatic joint debugging scheme of embodiment 2 in that: in embodiment 6, the local end (for example, the active end) in the three links involved in the aforementioned automatic joint debugging )
  • the transmission power adjustment of the optical transmitting device can be adjusted in combination with the optical receiving power feedback of the opposite end (for example, the slave end), while the optical receiving sensitivity adjustment or the FSO optical path/nutation adjustment can still use the local end (for example, active end) for optical receiving power feedback adjustment.
  • Fig. 9 shows an exemplary arrangement of systematic automatic joint adjustment based on dual-terminal power feedback.
  • the difference between the arrangement in Fig. 9 and Fig. 3 is that: 1) the management channel 121 is added (such as available Wi-Fi, mobile network, etc.); 2) the received optical power detection module of the local end and the received power synchronization module of the opposite end are integrated.
  • the received optical power acquisition module 122 in FIG. 3 replaces the received optical power detection module 103 in FIG.
  • the following changes can be made to both the transmission power adjustment link and the light receiving sensitivity adjustment link of the light emitting device at the local end (such as the active end), for example:
  • ⁇ Transmitting power adjustment of the optical transmitting device at the local end it can be performed based on the received optical power fed back from the opposite end, wherein the local end can feed back (synchronize) the situation of the received optical power to the opposite end through the management channel. That is to say, the free optical communication quality between the local end and the opposite end can be evaluated through the received optical power fed back by the opposite end. Hence, the condition of the free optical communication link between the local end and the opposite end can be known more clearly by means of the received optical power fed back by the opposite end.
  • ⁇ Optical receiving sensitivity adjustment link it can still be performed based on the receiving power of the local end (for example, the active end), but the negotiation module in Embodiment 3 can be considered to be removed. This is because this embodiment can use the management channel 121 to synchronize/feedback the sensitivity adjustment information of the local end to the peer end, so the negotiation module is not necessary.
  • Embodiment 7 Sensitivity adaptive adjustment based on local power feedback (excluding negotiation module)
  • Embodiment 7 performs adaptive sensitivity adjustment based on the received power of the local end, the negotiation module is removed; the sensitivity adjustment information of the local end is synchronized to the peer end through the management channel.
  • Fig. 10 shows an exemplary arrangement of sensitivity adaptive adjustment based on local power feedback. Compared with FIG. 5 , a management channel 121 is added in FIG. 10 , and a negotiation module is removed at the same time.
  • both the negotiation module and the management channel 121 can be reserved at the same time. In this case, those skilled in the art can choose to feed back or synchronize the sensitivity of the local end or the opposite end through the negotiation module or the management channel. Adjustment information.
  • FIG. 11 shows a flowchart of a power adaptive adjustment method operating within a free space optical (FSO) communication system adapted for free optical communication with another FSO communication system according to an example embodiment of the present disclosure , wherein the FSO communication system can be regarded as the first end, and the other FSO communication system can be regarded as the second end.
  • the method may include the following operations performed at the first end:
  • the first end may be a driving end, and the second end may be a driven end.
  • This step can be performed by sending the port. Therefore, the first end can actively send the first optical signal as a free optical communication signal to the slave end via the sending port with the initial sending power.
  • a second optical signal is received from the second end. This step can be performed through the receiving port.
  • the optical power of the second optical signal is detected as the optical received power of the first end.
  • This step can be performed by a received optical power detection module.
  • the received optical power receiving module may be in a network device/module in the FSO communication system, but this is not a limitation. In other embodiments, the received optical power receiving module is in a FSO device/module in the FSO communication system It is also possible.
  • the space link of the FSO communication system has the following characteristics: When the space link is affected by external factors such as weather, the optical receiving power at both ends increases and decreases at the same time, which is symmetrical, so the optical receiving power at the local end can To evaluate or estimate the received power of the peer end, thereby driving the adjustment of the transmit power of the local end, thereby realizing the adaptive transmit power adjustment of the link without additional management.
  • the optical received power of the first end can be compared with a preset power quality threshold (for example, the aforementioned first, second or third power quality threshold) to evaluate the first end and the first end.
  • a preset power quality threshold for example, the aforementioned first, second or third power quality threshold
  • the first end in response to the received optical power of the first end being lower than a preset power quality threshold, the first end may, for example, adaptively increase the transmitting power of the first end.
  • the first end in response to the received optical power of the first end being lower than a preset power quality threshold, the first end may adaptively perform an Adjustment.
  • the adjustment of the optical path may include, for example, nutating adjustment of the optical fiber coupling in the first end, so as to improve the coupling efficiency of the optical fiber. It will be understood that by adjusting the optical path, the transmission power of the first end can be increased in a manner of reducing the insertion loss of the link.
  • the first end in response to the fact that the transmitting power of the first end cannot be increased by adjusting the optical path, the first end may adaptively increase the transmitting power of the light emitting device in the first end. Furthermore, in response to the fact that the transmitting power of the light emitting device cannot be increased, the first end may adaptively adjust the light receiving sensitivity of the first end. In this way, architecture-level systematic automatic joint debugging based on single-ended closed-loop feedback is actually realized. This automatic joint debugging method is especially applicable to more complex link conditions.
  • the first end in response to the received optical power of the first end being lower than a preset power quality threshold, the first end may adaptively adjust the optical receiving sensitivity of the first FSO communication system, for example, from low light to Receive sensitivity switches to high light receive sensitivity.
  • the first end in response to the received light power of the first end being lower than a first preset power quality threshold, the first end may adaptively switch from low light receiving sensitivity to high light receiving sensitivity, or in response to The optical receiving power of the first end is higher than a second preset power quality threshold, and the first end can adaptively switch from high optical receiving sensitivity to low optical receiving sensitivity, wherein the second preset power quality threshold is greater than the first Preset power quality thresholds.
  • the first preset power quality threshold may be, for example, the first power quality threshold, the second power quality threshold or the third power quality threshold described above, and the second preset power quality threshold may be, for example, the above described The first power quality threshold, the third power quality threshold or the fourth power quality threshold, wherein the first preset power quality threshold is required to be greater than the second preset power quality threshold.
  • the first end may negotiate with the second end through free optical communication, and adjust the light receiving sensitivity of the first end according to the negotiation result.
  • adaptively adjusting the transmitting power of the first end may further include: receiving received optical power information from the second end; and receiving optical power information based on the received optical power information and the first end Both the optical receiving power and the transmitting power of the first end are adaptively adjusted.
  • the foregoing receiving the received optical power information from the second end may include, for example, receiving the received optical power information of the second end via a link other than the FSO link.
  • the FSO communication system will continuously (or repeatedly) execute the steps in block 1110 to block 1140 during the power adaptive adjustment process, so as to adjust the transmitting power to the power threshold that can guarantee predetermined quality communication (such as high-quality communication) . Therefore, the method may further include: receiving a fourth optical signal from the second end after sending the third optical signal with the adjusted transmit end power; detecting the optical power of the fourth optical signal as the first The updated optical received power of one end; based on the updated optical received power of the first end, adaptively adjust the transmit power of the first end; and send the second end to the second end with the adjusted transmit power Five light signals. I won't repeat them here.
  • FIG. 12 shows a flowchart of a power adaptive adjustment method for operation within a Free Space Optical (FSO) communication system, wherein the FSO communication system is adapted to conduct free optical communication with another FSO communication system, according to another example embodiment of the present disclosure.
  • Communication wherein the FSO communication system may be considered as the second end and the other FSO communication system may be considered as the first end.
  • the first end may be the driving end and the second end may be the driven end.
  • the method involves the following operations performed at the second end as the slave end:
  • a first optical signal is received from a first end at a first time.
  • the second end serves as the slave end, and the adjustment of its transmitting power can be adjusted following the adjustment of the transmitting power of the active end.
  • adaptively adjusting the transmitting power of the second end includes adjusting the optical path of the second end, adjusting the transmitting power of the light emitting device in the second end, and adjusting the power of the second end Adjustment of the light-receiving sensitivity within. The adjustment of the first end described above applies here equally to the adjustment of the second end.
  • the adjustment of these three links can be performed independently based on the comparison result of the second received light power and the first received light power, or can be adjusted as in the first end Joint debugging is carried out in the same way, that is to say: adjust the optical path of the second end first; then adjust the transmission power of the optical transmitting device in the second end when the transmission power cannot be increased, and after the transmission power reaches the maximum, Adjust the light receiving sensitivity.
  • the adjustment of the light receiving sensitivity of the second end may be performed based on a negotiation result with the first end. In some other embodiments, adjusting the light receiving sensitivity of the second end includes adjusting from low light receiving sensitivity to high light receiving sensitivity, or adjusting from high light receiving sensitivity to low light receiving field.
  • FIG. 13 shows a flowchart of a power adaptive adjustment method for operation in a free space optical (FSO) communication system according to yet another exemplary embodiment of the present disclosure, wherein the FSO communication system includes a first FSO communication system that communicates with each other in free optical communication and a second FSO communication system, the first FSO communication system may be regarded as a first end, and the other two FSO communication systems may be regarded as a second end.
  • the method can include:
  • the first end transmits a first optical signal to the second end at an initial transmit power
  • the second end detects the optical power of the first optical signal as the first optical received power of the second end
  • the second end transmits a second optical signal to the first end
  • the first end detects the optical power of the second optical signal as the second optical received power
  • the first end adaptively adjusts the transmit power of the first end based on the second received optical power
  • the first end transmits a third optical signal to the second end at the adjusted transmit power
  • the second end detects the optical power of the third optical signal as a third optical received power
  • the second end adaptively adjusts the transmit power of the second end.
  • the first end can be used as the active end, and the second end can be used as the driven end.
  • the method can realize the linkage adjustment of the transmitting power of the first end and the second end. Since the above has already described in detail how to adjust the transmit power of the first end and the second end, details will not be repeated here.
  • the power self-adaptive scheme based on single-ended closed-loop feedback, it can realize self-adaptive adjustment of FSO system transmission power, which is conducive to reducing the difficulty of engineering implementation of installation and commissioning, and improving the adaptability of the system to various environments and changes , especially when the environment is deteriorating, it can still maintain a high pass rate.
  • the characteristics of the FSO communication space link can be fully utilized, reducing the need for an additional management link for adaptive transmission power adjustment.
  • the architecture-level systematic automatic joint debugging scheme based on power feedback (including: single-ended closed-loop feedback or combination of double-ended power feedback), it can be gradually degraded according to the degree of environmental degradation, and the overall communication of the system link can be improved. For example, when the link status is good, high link quality is guaranteed; when the link status is degraded, the link is basically available.
  • automatic adjustment can be realized to reduce labor maintenance costs.
  • adaptive FSO optical path/nutation calibration based on cross-device power feedback, it can fully reuse the power detection function of network equipment and simplify the design of FSO equipment (especially for the separate deployment of network equipment and FSO equipment, the more FSO equipment the smaller the better).
  • the linkage between network equipment and FSO equipment can jointly optimize link insertion loss.

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Abstract

本公开涉及自由空间光(FSO)通信系统及其功率自适应调节方法。根据该方法，第一FSO通信系统以初始发端功率向适于与其进行自由光通信的第二FSO通信系统发送第一光信号。第一FSO通信系统接收来自第二FSO通信系统的第二光信号，并检测第二光信号的光功率以作为所述第一FSO通信系统的光接收功率。第一FSO通信系统基于该光接收功率来自适应地调整所述第一FSO通信系统的发端功率，并以经调整的发端功率向第二FSO通信系统发送第三光信号。

Description

自由空间光通信系统及其功率自适应调节方法
本申请要求于2021年5月10日提交中国国家知识产权局、申请号为202110504458.0、申请名称为“自由空间光通信系统及其功率自适应调节方法”的中国专利申请的优先权，其全部内容通过引用结合在本申请中。
技术领域
本公开的各实施例涉及光通信领域，更具体地涉及一种自由空间光(FSO)通信系统及其功率自适应调节方法。
背景技术
自由空间光(Free Space Optics，FSO)通信是基于激光通信的无线传输方式，等同于“隐形光纤”，其相比传统的射频无线技术，具有大带宽、免频谱申请、无电磁干扰等优势。随着技术的进步和成本的优化，FSO通信已经逐渐从军用、星间通信延伸至民用的地面短距通信。
发明内容
本公开的目的在于提供了一种改进的自由光(FSO)通信系统及其功率调节方法，其可以提供优化的功率自适应调整能力，并且可以提升FSO通信系统的整体可通率。
根据本公开的第一方面，提供了一种功率自适应调节方法。该方法包括：第一自由空间光FSO通信系统以初始发端功率向适于与所述第一FSO通信系统进行自由光通信的第二FSO通信系统发送第一光信号；所述第一FSO通信系统接收来自所述第二FSO通信系统的第二光信号；所述第一FSO通信系统检测所述第二光信号的光功率，以作为所述第一FSO通信系统的光接收功率；所述第一FSO通信系统基于所述第一FSO通信系统的光接收功率，自适应地调整所述第一FSO通信系统的发端功率；以及所述第一FSO通信系统以经调整的发端功率向所述第二FSO通信系统发送第三光信号。
基于上述的功率自适应调节方法，第一FSO通信系统可以作为主动端将所接收的来自对端的自由光通信信号的光功率作为本端的光接收功率，并且基于本端的光接收功率来实现本端的发端功率调整。也就是说，本端的发端功率是基于单端的闭环反馈来实现的。利用第一方面的功率自适应调节方法，这可以实现第一FSO系统发端功率的自适应调整，有利地降低安装调测的工程实施难度，提高系统对各种环境及变化的适应能力。
在一些实施例中，自适应地调整所述第一FSO通信系统的发端功率包括：响应于所述第一FSO通信系统的光接收功率低于预设功率质量阈值，所述第一FSO通信系统自适应地增加所述第一FSO通信系统的发端功率。在该些实施例中，光接收功率低于预设功率质量阈值，这意味着两端的自由光通信不符合预定通信质量要求，这里可以通过增加发端功率来提高两端的自由光通信质量。
在一些实施例中，自适应地调整所述第一FSO通信系统的发端功率包括：响应于所 述第一FSO通信系统的光接收功率低于预设功率质量阈值，所述第一FSO通信系统自适应地增加所述第一FSO通信系统中的光发射器件的发射功率。在该些实施例中，增加发射功率可以作为调整发端功率的主要方式之一。
在一些实施例中，自适应地调整所述第一FSO通信系统的发端功率包括：响应于所述第一FSO通信系统的光接收功率低于预设功率质量阈值，所述第一FSO通信系统自适应地对所述第一FSO通信系统内的光路进行调整。在该些实施例中，光路调整可以减少光路的基础损耗，因此也可以用于调整发端功率。
在一些实施例中，自适应地对所述第一FSO通信系统内的光路进行调整包括：对所述第一FSO通信系统内的光纤耦合进行章动调整，以提高所述光纤的耦合效率。在该些实施例中，可以通过章动调整提高光纤的耦合效率来调整发端功率。
在一些实施例中，自适应地调整所述第一FSO通信系统的发端功率还包括：响应于以光路调整方式而无法使得所述第一FSO通信系统的所述光接收功率提升，所述第一FSO通信系统自适应地增加所述第一FSO通信系统中的光发射器件的发射功率。在该些实施例中，这提供了在光路调整和改变发射功率之间进行联调以改变发端功率的能力。
在一些实施例中，自适应地调整所述第一FSO通信系统的发端功率还包括：响应于所述光发射器件的发射功率无法增加，则所述第一FSO通信系统自适应地对所述第一FSO通信系统的光接收灵敏度进行调整。在该些实施例中，这提供了在发射功率调整和光接收灵敏度调整之间进行联调来自适应调整发端功率的能力。
在一些实施例中，自适应地调整所述第一FSO通信系统的发端功率包括：响应于所述第一FSO通信系统的光接收功率低于预设功率质量阈值，所述第一FSO通信系统自适应地对所述第一FSO通信系统的光接收灵敏度进行调整。在该些实施例中，光接收灵敏度的调整可以导致光接收功率的变化，并且由此可以作为自适应功率调节功率的子方案。
在一些实施例中，自适应地调整所述第一FSO通信系统的发端功率包括：响应于所述第一FSO通信系统的光接收功率低于预设功率质量阈值，所述第一FSO通信系统经由自由光通信与所述第二FSO通信系统进行协商；以及基于所述协商结果，对所述第一FSO通信系统的光接收灵敏度进行调整。在该些实施例中，可以通过协商来实现收端和发端两者的光接收灵敏度的调整，以这种方式，可以使得光接收灵敏度的调整更为准确。
在一些实施例中，自适应地调整所述第一FSO通信系统的发端功率包括：响应于所述第一FSO通信系统的光接收功率低于第一预设功率质量阈值，所述第一FSO通信系统自适应地从低光接收灵敏度切换至高光接收灵敏度；或响应于所述第一FSO通信系统的光接收功率高于第二预设功率质量阈值，所述第一FSO通信系统自适应地从高光接收灵敏度切换至低光接收灵敏度，其中第二预设功率质量阈值大于第一预设功率质量阈值。在该些实施例中，可以在低通信质量的情况下，切换至高光接收灵敏度，以提高FSO通信的整体可通率；而在通信链路改善至高通信质量的情况下，可以使得高光接收灵敏度返回至低光接收灵敏度，以提高传输速率。
在一些实施例中，还包括：在以调整后的发端功率发送第三光信号之后，接收来自所述第二FSO通信系统的第四光信号；检测所述第四光信号的光功率，以作为所述第一FSO通信系统的更新的光接收功率；基于所述第一FSO通信系统的更新的光接收功率，自适应地调整所述第一FSO通信系统的发端功率；以及以经调整的发端功率向所述第二FSO通信系统发送第五光信号。在该些实施例中，本端的功率自适应调节会在动态中持续进行，其包括持续地检测本端的光接收功率，然后基于更新的光接收功率来调整发端 功率。将会理解，该些实施例中的功率自适应调整是与对端的功率自适应调整联动进行的。
在一些实施例中，自适应地调整所述第一FSO通信系统的发端功率还包括：接收来自所述第二FSO通信系统的接收光功率信息；以及基于所述接收光功率信息和所述第一FSO通信系统的光接收功率两者，来自适应地调整所述第一FSO通信系统的发端功率。在该些实施例中，可以基于本端和对端两者的光接收功率来调整发端功率，这可以实现更为精确和快速的发端功率调整。
在一些实施例中，接收来自所述第二FSO通信系统的接收光功率信息包括：经由FSO链路之外的链路来接收所述第二FSO通信系统的所述接收光功率信息。利用FSO链路之外的链路，这可以使得第一FSO系统更为便利地接收来自第二FSO通信系统所反馈的信息，并且依此作出更准确和快速的调整。
根据本公开的第二方面，提供了一种功率自适应调节方法。该方法包括：第二自由空间光FSO通信系统在第一时间接收来自适于与所述第二FSO通信系统进行自由光通信的第一FSO通信系统的第一光信号；所述第二FSO通信系统检测所述第一光信号的光功率，以作为所述第二FSO通信系统的第一光接收功率；所述第二FSO通信系统在第二时间接收来自所述第一FSO通信系统的第二光信号；所述第二FSO通信系统检测所述第二光信号的光功率，以作为所述第二FSO通信系统的第二光接收功率；所述第二FSO通信系统基于所述第二光接收功率与所述第一光接收功率的比较结果，自适应地调整所述第二FSO通信系统的发端功率。
在该第二方面的功率自适应调节方法中，类似于第一FSO通信系统，第二FSO通信系统也基于本端所接收的光接收功率来进行功率的自适应调整。但是，将会理解，与第一FSO通信系统相比，第二FSO通信系统通常是作为从动端而跟随作为主动端的第一FSO通信系统来进行自适应调整的。
根据本公开的第三方面，提供了一种在通信系统内操作的功率自适应调节方法，所述通信系统包括彼此自由光通信的第一自由空间光FSO通信系统和第二FSO通信系统，该方法包括：所述第一FSO通信系统以初始发端功率向所述第二FSO通信系统发送第一光信号；所述第二FSO通信系统检测所述第一光信号的光功率，以作为所述第二FSO通信系统的第一光接收功率；所述第二FSO通信系统向所述第一FSO通信系统发射第二光信号；所述第一FSO通信系统检测所述第二光信号的光功率，以作为第二光接收功率；所述第一FSO通信系统基于所述第二光接收功率，自适应地调整所述第一FSO通信系统的发端功率；所述第一FSO通信系统以经调整的发端功率向所述第二FSO通信系统发送第三光信号；所述第二FSO通信系统检测所述第三光信号的光功率，以作为第三光接收功率；以及基于所述第三光接收功率与所述第一光接收功率的比较结果，所述第二FSO通信系统自适应地调整所述第二FSO通信系统的发端功率。
上述第三方面的功率自适应调节方法提供了在第一FSO通信系统和第二FSO通信系统两端进行功率自适应调节的系统级方案。利用该系统级方案，可以提高整个通信系统对各种环境及变化的适应能力，尤其是在环境劣化时。
根据本公开的第四方面，提供了一种第一自由空间光FSO通信系统。该系统包括：发送端口，其适于以初始发端功率向适于与所述第一FSO通信系统进行自由光通信的第二FSO通信系统发送第一光信号；接收端口，其适于接收来自所述第二FSO通信系统的第二光信号；接收光功率检测模块，其适于检测所述第二光信号的光功率，以作为所述 第一FSO通信系统的光接收功率；以及自适应功率调节模块，其适于基于所述第一FSO通信系统的光接收功率，自适应地调整所述第一FSO通信系统的发端功率；其中所述发送端口还适于以经调整的发端功率向所述第二FSO通信系统发送第三光信号。
在一些实施例中，所述自适应功率调节模块包括：自适应发射功率调节模块，其适于在所述第一FSO通信系统的光接收功率低于预设功率质量阈值时，自适应地调整所述第一FSO通信系统内的光发射器件的发射功率；
在一些实施例中，所述自适应功率调节模块包括：光路调整模块，其适于在所述第一FSO通信系统的光接收功率低于预设功率质量阈值时，对所述第一FSO通信系统内的光路进行调整。
在一些实施例中，所述光路调整模块还包括章动模块，所述章动模块适于在所述第一FSO通信系统的光接收功率低于预设功率质量阈值时，对所述第一FSO通信系统内的光纤耦合进行章动调整，以提高光纤耦合的效率。
在一些实施例中，所述自适应功率调节模块包括：灵敏度自适应调整模块，所述灵敏度自适应调整模块适于在所述第一FSO通信系统的光接收功率低于预设功率质量阈值时，自适应地调整所述第一FSO通信系统的光接收灵敏度。
在一些实施例中，自适应地调整所述第一FSO通信系统的发端功率包括：响应于所述第一FSO通信系统的光接收功率低于预设功率质量阈值，所述自适应功率调节模块自适应地增加所述第一FSO通信系统的发端功率。
在一些实施例中，所述灵敏度自适应调整模块还包括：协商模块，所述协商模块适于在所述第一FSO通信系统的光接收功率低于预设功率质量阈值时，自适应地经由自由光通信与所述第二FSO通信系统进行协商，以确定所述第一FSO通信系统的光接收灵敏度；切换模块，其适于基于所协商的所述第一FSO通信系统的光接收灵敏度而在不同的光接收灵敏度之间进行切换。
在一些实施例中，所述自适应功率调节模块还被配置成：响应于所述第一FSO通信系统的光接收功率低于预设功率质量阈值，则首先使用光路调整模块对所述第一FSO通信系统内的光路进行调整；响应于所述光路的调整无法使得所述第一FSO通信系统的发端功率得以提升，则使用自适应发射功率调节模块来自适应地增加所述第一FSO通信系统中的光发射器件的发射功率；以及响应于所述光发射器件的发射功率无法增加，则使用灵敏度自适应调整模块来自适应地对所述第一FSO通信系统的光接收灵敏度进行调整。
在一些实施例中，该通信系统还包括：管理通道，所述第一FSO通信系统适于经由所述管理通道以自由光通信之外的通信链路，接收来自所述第二FSO通信系统的接收光功率信息，所述自适应功率调节模块适于基于所述接收光功率信息和所述第一FSO通信系统的光接收功率两者，来自适应地调整所述第一FSO通信系统的发端功率。
根据本公开的第五方面，提供了一种第二自由空间光FSO通信系统。该系统包括：接收端口，其适于在第一时间接收来自适于与所述第二FSO通信系统进行自由光通信的第一FSO通信系统的第一光信号，以及在第一时间之后的第二时间接收来自所述第一FSO通信系统的第二光信号；接收光功率检测模块，其适于检测所述第一光信号的光功率，以作为所述第二FSO通信系统的第一光接收功率，以及检测所述第二光信号的光功率，以作为所述第二FSO通信系统的第二光接收功率；自适应功率调节模块，其适于基于所述第二光接收功率与所述第一光接收功率的比较结果，自适应地调整所述第二FSO通信 系统的发端功率；发送端口，其适于以经调整的发端功率来向所述第一FSO通信系统发送光信号。
根据本公开的第六方面，提供了一种通信系统。该通信系统包括彼此进行自由光通信的根据第四方面中所述的第一自由空间光FSO通信系统和根据第五方面所述的第二FSO通信系统。
上述第四、第五和第六方面的通信系统可以与上面的第一、第二和第三方面的通信系统相对应，并且获得与之相对应的技术效果。
还应当理解，发明内容部分中所描述的内容并非旨在限定本公开的实施例的关键或重要特征，亦非用于限制本公开的范围。本公开实施例的其它特征将通过以下的描述变得容易理解。
附图说明
结合附图并参考以下详细说明，本公开各实施例的上述和其他特征、优点及方面将变得更加明显。在附图中，相同或相似的附图标记表示相同或相似的元素，其中：
图1A示出了常规的分体式FSO通信系统的示意性布置。
图1B示出了常规的一体式FSO通信系统的示意性布置。
图2A示出了根据本公开的示例实施例的基于单端闭环反馈的光发射器件的功率自适应调整方案的示例性布置。
图2B示出了根据本公开的示例实施例的各个不同功率质量阈值和通信质量的对应关系的示例。
图3示出了根据本公开的示例实施例的基于单端闭环反馈的架构级系统性自动联调方案的示例性布置。
图4A示出了根据本公开的示例实施例的三环节联调构想的流程示意图。
图4B示出了根据本公开的示例实施例的三环节联调的具体示例的流程示意图。
图5示出了根据本公开的示例实施例的基于单端闭环反馈的灵敏度自适应调整子方案的示例性布置。
图6A至图6C示出了根据本公开的示例实施例的基于单端内的跨设备/模块的功率反馈的自适应FSO光路调整子方案的示例性布置。
图7示出了根据本公开的示例实施例的基于单端内的跨设备/模块的功率反馈的自适应FSO章动调整子方案的示例性布置。
图8示出了根据本公开的示例实施例的基于对端功率反馈的光发射器件的功率自适应调整方案的示例性布置。
图9示出了根据本公开的示例实施例的基于双端功率反馈的架构级系统性自动联调方案的示例性布置。
图10示出了根据本公开的示例实施例的基于本端功率反馈的灵敏度自适应调整(不含协商模块)方案的示例性布置。
图11示出了根据本公开的示例实施例在自由空间光(FSO)通信系统内操作的功率自适应调节方法的流程图。
图12示出了根据本公开的另一示例实施例的自由空间光(FSO)通信系统内操作的功率自适应调节方法的流程图。
图13示出了根据本公开的又一示例实施例的自由空间光(FSO)通信系统内操作的功率自适应调节方法的流程图。
具体实施方式
下面将参照附图更详细地描述本公开的实施例。虽然附图中显示了本公开的某些实施例，然而应当理解的是，本公开可以通过各种形式来实现，而且不应该被解释为限于这里阐述的实施例，相反提供这些实施例是为了更加透彻和完整地理解本公开。应当理解的是，本公开的附图及实施例仅用于示例性作用，并非用于限制本公开的保护范围。
图1A示出了常规的分体式FSO通信系统的示意性布置。如图1A所示，在该分体式FSO通信系统中，由网络设备产生通信光(通常为激光)，FSO设备只作为光透传，即通过光纤连接从网络设备接收通信光，通信光经过FSO设备的内部传输后直接发送到作为对端的另一FSO通信系统(在该示例中，也为分体式FSO通信系统，但这并非限制，该另一FSO通信系统也可以是如后面图1B所示的一体式FSO通信系统)。上述FSO设备不会改变光信号，仅调整光的扩束/收束、光路等；对端FSO设备接收到通信光后，经过FSO设备的内部传输后，耦合到光纤中，而后通过光纤连接至网络设备。
如图1A所示，常规的FSO设备可以包括以下组件：透镜组件、粗跟踪和精跟踪执行机构、功率探测模块、计算模块、信标光等。在一些实施例中，信标光和粗跟踪执行机构为可选项。下面将对这些组件进行简单地介绍。
透镜组件通常为透镜组，主要用于实现光学扩束、分光等功能；其也可采用特殊设计的单透镜，也可以是可实现相同透镜功能的器件，如LCoS(Liquid Crystal on Silicon，硅基液晶)。
信标光主要用于两端设备的初步对准，可配合粗跟踪执行机构工作。仅作为示例，该信标光可以是可见的激光。
功率探测模块主要用于探测接收到的通信光和信标光(从对端发送)，并且耦合至计算模块。在一些实施例中，功率探测可由透镜组件通过分光片导出一小部分光信号用于探测。在另一些实施例中，也可以在光信号耦合到光纤之前利用分光器件导出一小部分光信号用于探测。仅作为示例，该功率探测模块可以是光电探测器。
计算模块可以在接收到探测的数据之后，执行相应的计算功能，例如确定自由光通信的质量是否符合要求，以便将计算结果随后用于驱动粗跟踪和精跟踪执行机构。粗跟踪和精跟踪的功率探测模块可以相同，也可以不同，在此不做限制。仅作为示例，该计算模块可以是芯片、电路板等。
粗跟踪和精跟踪执行机构：粗跟踪执行机构主要用于设备的大粒度对准，如安装时设备的对准、设备长期使用后由于重力等影响导致的较大幅度偏差的校准等；精跟踪执行机构主要用于应对抖动(如大气扰动等)导致的光路偏差校准等。在图1A和图1B(后面将进一步描述)的示例中，粗跟踪执行结构可以对虚线框中的组件整体执行粗调整。仅作为示例，粗跟踪执行结构可以是云台等具体的装置；精跟踪执行机构可以是微机电系统(MEMS)、音圈电机等。
光发射与接收孔：用于FSO设备通信光的发送与接收。
光纤接口：用于对接网络设备。
除了上述组件之外，在一些FSO通信系统系统中，在光纤耦合至光纤接口的连接段， 还可以包括章动模块，该章动模块可以根据接收光功率情况进行光纤耦合的调整，以提高光纤的耦合效率，这特别地对于耦合光纤是单模光纤的情况是特别有用的。
下面将介绍常规FSO通信系统的示例性工作流程，该工作流程可以主要包括以下两个阶段：
●粗调阶段：在粗调阶段，可以使用信标光，由功率探测模块通过探测信标光的接收功率强度情况，驱动粗跟踪执行机构进行调整，将两端设备大致对准，其具体实现可以是手动、手动+自动或全自动执行，在此不做限制。需要注意的是，有些系统可能采用非功率探测的方式来进行信标光的观测，由于此处非本发明重点，因此未一一列出，也不做限制。
●精调阶段：使用通信光，由功率探测模块通过探测通信光的接收功率强度情况，驱动精跟踪执行机构进行调整，实现两端设备光路的精准对齐，使得两端设备接收的光功率达到良好状态。
图1B示出了常规的一体式FSO通信系统。该一体式FSO通信系统与分体式FSO通信系统的不同在于：在一体式FSO通信系统中，图1A中的“网络设备”和“FSO设备”在图1B中分别以“网络模块”和“FSO模块”的形式存在，以及其中的光纤耦合可以无需经由光纤接口来实现。在系统的组成、工作流程的其他方面，该一体式FSO通信系统和与分体式FSO通信系统是类似地，因此在此不再赘述。将会理解，“网络设备”和“网络模块”两者的结构和功能是相似的，“FSO设备”和“FSO模块”两者的结构和功能是相似的。
这里需要说明的是：为了方便起见，在本文的一些实施例中，“网络设备”和“网络模块”两者可互换使用，以及“FSO设备”和“FSO模块”两者可互换使用，除非文中特别地指明其是针对分体式FSO通信系统或是一体式FSO通信系统而使用。
不管是一体式FSO通信系统还是分体式FSO通信系统，可通率是衡量FSO通信系统性能的重要指标，其主要与链路插损、FSO系统内光发射器件的发射功率和接收端接收灵敏度(简称“光接收灵敏度”)相关。下面是这些关键参数的一些描述：
●链路插损：与FSO设备/模块的光路校准或章动调整的精准度、器件、环境扰动等相关。其中，FSO设备/模块的光路校准或章动调整为技术可控部分，是本公开所重点关注的。光路校准或章动调整的精准度越高，链路插损则越小，FSO通信系统的功率裕量越高，对可通率越有利。
●发射功率：通过对与FSO设备对接的网络设备或一体式FSO通信系统的网络模块内的光发射器件的驱动功率进行设置。发射功率会影响对端的接收功率，在相同的链路插损和收端灵敏度条件下，发射功率越大，对端的接收功率越高，对可通率越有利(以接收功率不高于网络设备/模块可接收上限为前提)。
●光接收灵敏度：由网络设备或模块的接收光模块决定，接收灵敏度越高，通信系统的动态范围越大，对可通率越有利。需要注意的是，一般情况下，光模块的接收灵敏度越高，速率可能会有所降低。
●发端功率：其由FSO通信系统向外部所发射的光信号的功率定义，上述链路插损、发射功率以及光接收灵敏度的变化或不同可以改变发端功率。
对于上述常规的FSO通信系统(不管是一体式还是分体式)的发端功率的设置或调节，一般有以下几种方案：
方案一、是在安装时对网络设备或模块的发射功率(或光发射器件的驱动功率)进 行设置后固定，后续一般无法自适应调整，此时发端功率由发射功率或驱动功率决定。该方案一的缺点在于：与光纤不同，FSO空间链路质量受大气环境影响，因此此类系统的问题是：恒定的光功率难以应对复杂多变、存在不确定性波动的实际应用环境。一方面，不同环境对光源输入功率需求不同；另一方面，当大气环境劣化时，如果没能及时提高发端功率，可能导致链路质量大幅下降(大量丢包、断开等)，影响链路可通率。
方案二、增加了自由光通信之外的链路作为管理通道来反馈对端的接收功率，例如如Wi-Fi、移动网络等，该方案二可以改进方案一无法自适应调整发端功率的问题，其例如可以通过管理通道获取对端的光接收功率信息，以对端光接收功率作为判决依据，自动调整本端的发射功率，实现基于收端接收功率反馈的发端功率自适应调整。然而，该方案二的不足之处在于需要增加通信之外的链路作为管理通道，但需要部署FSO通信系统的区域，往往不便于部署其他通信方案(如带有电磁干扰的无线射频方案、需要线缆铺设的有线通信方案等)，因此方案的应用存在局限性。同时，此类方案仅自适应调节发射功率，但FSO通信系统的可通率与多个要素相关，当发射功率调节到极限后，如果收端的接收功率仍不能满足要求，仍会面临链路质量无法保障的问题。
此外，对于分体式FSO通信系统，FSO设备与网络设备往往只是简单对接，因此二者存在部分类似功能模块设计冗余问题，较为明显的是，网络设备往往具备功率探测功能，如果其可用于FSO设备的功率探测需求，则FSO设备可节约功率探测模块。
本公开的目的至少在于解决或缓解常规的FSO通信系统中存在的以下问题，即：常规FSO通信系统自适应功率调整需要额外的管理链路的问题；或者FSO通信系统缺乏架构级的自动联调——FSO设备光路校准/章动调整、发射功率调整、光接收灵敏度调整三个环节缺乏联动——未能充分发挥抗扰动能力，整体可通率有待提升的问题，等。
以下将通过各个实施方式来描述本公开的各种可能技术方案。
第一实施方式：无额外管理通道(或无额外通信链路)下的功率自适应调整方案
该第一实施方式的方案是建立在无额外管理通道(或无额外通信链路)的功率自适应调整方案，术语“无额外管理通道/无额外通信链路”意味者不存在除自由光通信的管理通道/链路之外的额外管理通道/链路，这些额外管理通道(或无额外通信链路)例如可以通过WIFI、移动网络、蓝牙、Zigbee等技术实现。该第一实施方式可以包括如下的多个实施例。将会理解，在不互相矛盾的情况下，这些多个实施例可以任意组合，并且这些组合的方案均在本公开的精神和保护范围之内。
实施例1：基于单端闭环反馈的发端功率自适应调整方案
在该实施例1中，其发射功率自适应调整方案完全是基于单端闭环反馈而进行的，术语“单端闭环反馈”意味着FSO通信系统可以仅依据本端所接收的光接受功率信号对本端的发射功率进行调整，而不依赖来自对端的光接收功率信号。
经理论分析和实测发现，FSO通信系统的空间链路存在如下特性：当空间链路受天气等外界因素影响时，两端的光接收功率同增同减，具有对称性。
基于以上特性，本实施例的构思在于可以通过本端的光接收功率来评估或推算对端的接收功率，从而驱动本端的发端功率的调整，由此实现免额外管理链路的自适应发端功率调整。
如图2A所示，可以将彼此通信的两个FSO通信系统划分为主动端10和从动端20，其中主动端10为先启动发端功率调整的一端，从动端20为跟随调整的另一端。这里，假定左侧的FSO通信系统为主动端10，而右侧的FSO通信系统为从动端20。将会理解， 该划分并不构成对FSO通信系统的任何限制。在各个实施例中，主动端10和从动端20的配置可以完全相同或不同。仅作为示例，如图2A所示，主动端10和从动端20的配置是相同的。例如，主动端10可以包括发送端口101、接收端口104、接收光功率检测模块103和自适应发射功率调节模块102；而从动端20也同样地可以包括发送端口201、接收端口204、接收光功率检测模块203和自适应发射功率调节模块202。作为示例，上面的接收光功率检测模块103、203例如可以光电探测器，并且可以集成在例如光模块中；自适应发射功率调节模块102、202例如可以是光发射器件的驱动电路、驱动芯片等。这里，需要注意的是，尽管在图2A中发送端口、接收端口、接收光功率检测模块和自适应发射功率调节模块均被布置在虚线框中所指示的网络设备/模块100或200中，但这仅仅是示例，其不构成对发送端口、接收端口、接收光功率检测模块和自适应发射功率调节模块在主动端/从动端内的布置位置的任何限制。还应当理解，在其他实施例中，彼此进行自由光通信的两个FSO通信系统中的任一端可以作为主动端，另一端作为从动端。
具体地，在该实施例中，基于单端闭环反馈的发端功率自适应调整过程例如可以通过对主动端内的光发射器件的发射功率的调整来实现。具体过程如下：
首先，主动端10可以以初始发端功率经由发送端口101向从动端20发送光通信信号，然后接收端口104可以接收来自从动端20的光通信信号。接着，接收光功率检测模块103可以检测所接收的光信号的光功率，并将其同步地提供给自适应发射功率调节模块102。将会理解，主动端10所检测的接收光功率即为主动端的光接收功率。而后，自适应发射功率调节模块102可以基于主动端所接收的光接收功率对主动端中的光发射器件的发射功率进行自适应调整，从而调整主动端10的发端功率。
如前所述的，FSO通信系统的空间链路的两端的光接收功率具有同增同减的特性，因此，基于主动端所接收的光接收功率，自适应发射功率调节模块102可以使用其来评估主动端10和从动端20之间的自由光通信质量，并且可以依据所评估的自由光通信质量，来自适应地调整(例如，增加或降低)主动端内的光发射器件的发射功率，由此自适应调节主动端的发端功率。
在一些实施例中，基于主动端的接收光功率来评估自由光通信质量可以包括：将主动端10的光接收功率与预设功率质量阈值进行比较。仅作为示例，如图2B所示，该预设功率质量阈值可以例如包括第一功率质量阈值、第二功率质量阈值、第三功率质量阈值、第四功率质量阈值，这些阈值可以与不同的通信质量相对应。譬如，第一功率质量阈值可以是保障正常通信质量的功率阈值，第二功率质量阈值可以是指示无法进行基本通信(低质量通信)的功率阈值，第三功率质量阈值可以是保障高质量通信的功率阈值，而第四功率阈值可以是指示光接收功率过高的功率阈值。将会理解，在其他实施例中，预设功率质量阈值可以包括更多或更少的不同功率质量阈值。此外，这些功率质量阈值可以随不同环境条件(例如，不同的环境或气候条件，包括雾霾天、雾天、雨天、或沙尘天气)而有所不同。在一些实施例中，这些不同功率质量阈值可以根据本领域技术人员的经验进行设置。
在一些实施例中，上述自适应地调整主动端中的光发射器件的功率可以包括对主动端中的光发射器件的发射功率进行增加、减小，或者保持不变。
将会理解，上述自适应地调整光发射器件的发射功率的方式仅仅是调节发端功率的一种方式，对发端功率调节的其他方式还可以包括但不限于：对主动端内的光路进行校准或调整、对主动端内的光接收灵敏度进行调整。。
例如，对主动端内的光路进行自适应校准或调整可以包括：基于主动端处所接收的光接收功率，对FSO设备/模块内的光路进行调整或校准，这例如可以通过如图1A和图1B中所示的粗跟踪执行机构或精跟踪执行机构对主动端内的光路(该光路包括设置在其上的光学组件，例如透镜组件)、和/或对主动端内的章动模块进行调整来实现，其中对主动端内的章动模块进行调整可以提高光纤的耦合效率。在本文，“对光路进行调整”或“对光路进行校准”可以认为具有相同含义，它们可以互换使用。
又例如，对主动端内的光接收灵敏度进行调整，可以包括：基于主动端处所接收的光接收功率，对主动端的光接收灵敏度进行调整。例如，可以在主动端内提供多个光接收灵敏度模块，以供主动端进行切换使用。
从上面的讨论可知，前面描述的自适应发射功率调节模块102可以作为更为广泛的自适应功率调节模块的一部分而存在。在一些实施例中，自适应功率调节模块还可以包括自适应光路调整模块(其例如可以包括粗/精跟踪执行机构)、灵敏度自适应调整模块(其例如可以由光模块构成)，如后面将会进一步描述的。
与此同时，在通过自适应发射功率调节模块102进行自适应调整的实施例中，一旦自适应发射功率调节模块102自适应地调整主动端10的发端功率，那么主动端10就可以以经调整的发端功率向从动端10发送具有调整后功率的光信号。
相应地，基于单端闭环反馈的从动端侧的功率自适应调整过程如下：
从动端20可以经由接收端口201接收来自主动端10的光信号，并且经由接收光功率检测模块202检测该光信号的光功率作为从动端的光接收功率，并同步给自适应发射功率调节模块203。光功率检测模块202会一直检测来自主动端的光信号。一旦自适应发射功率调节模块203确定从动端20处的光接收功率发生变化，则可以确定主动端10已经完成发端功率调整。随后，从动端20可以依据本端的光接收功率的变化，来自适应调整从动端20的发端功率。
类似地，上述自适应地调整从动端20的发端功率可以包括对从动端的发端功率进行增加、减小，或者保持不变。进一步地，上述自适应地调整从动端的发端功率的方式可以包括但不限于：对从动端的光发射器件的发射功率进行自适应调整、对从动端内的光路进行校准或调整、对从动端内的光接收灵敏度进行调整。更进一步地，对从动端内的光路进行校准或调整可以包括：按如图1A和图1B中所示的粗跟踪执行机构或精跟踪执行机构对从动端内的光路(该光路包括设置在其上的光学组件，例如透镜组件)进行调整或校准、对主动端内的章动模块进行调整以提高光纤的耦合效率。
从以上的描述可知，在该基于单端闭环反馈的功率自适应FSO通信系统的该实施例中，其主动端或从动端的功率自适应调整均是基于本端所检测的光接收功率情况而进行的，而不依赖于对端所反馈的光接收功率。因此，在该些实施例中，额外的管理链路(例如，WIFI、移动网络等)可以省略。
实施例2：基于单端闭环反馈的架构级系统性自动联调方案
类似于实施例1，该实施例2也是基于单端闭环反馈，并且以本端的接收功率作为自由光通信质量的判决依据，但与实施例1有所不同的是，该实施例2可以至少在以下三个环节进行自动化联动调整：a)对主动端/从动端的光发射器件的发射功率进行自适应调整、b)对主动端/从动端内的光路进行校准或调整(其包括对光纤耦合进行章动调整)、c)对主动端/从动端内的光接收灵敏度进行调整。
为了实现上述联调，图3示出了基于单端闭环反馈的架构级系统性自动联调的相关 架构。为了方便起见，这里以主动端10来描述。将会理解，从动端的配置可以与主动端相同或不同。如图3所示，该主动端10示出了网络设备/模块100和FSO设备/模块150。特别地，该网络设备/模块120除了包括发送端口101、接收端口104、接收光功率检测模块103和自适应发射功率调节模块102之外，还可以进一步包括灵敏度自适应调整模块105，该灵敏度自适应调整模块105可以基于接收光功率检测模块103所检测的光接收功率(其例如可以通过与预设功率质量阈值进行比较，来评估所述主动端和从动端之间的自由光通信质量)而自适应地调整主动端的光接收灵敏度。FSO设备/模块150可以包括光路调整模块151，该光路调整模块151同样地可以基于接收光功率检测模块103所检测的光接收功率，而自适应地对主动端内的光路进行调整。特别地，在一些实施例中，光路调整模块151可以包括章动模块，以便对所述主动端10内的光纤耦合(例如，网络设备/模块和FSO设备/模块150之间的光纤耦合)进行章动调整，以提高光纤耦合的效率。
在上述图3的架构布置中，可以进一步对发端功率的自适应调整进行优化。例如，可以使得上面描述的3个环节a)-c)进行联动，从而实现这三个环节的自动化联调。通过这种方式，可以提高FSO通信系统在不同环境条件下的自适应能力，提升系统的整体可通率。
仅作为示例，可以按照图4A的流程来实现这三个环节的联调，例如，
1)优先调整FSO设备/模块的光路/章动。具体而言，主动端的网络设备/模块的接收光功率检测模块103可以检测光接收功率，并将功率情况反馈给FSO设备/模块的光路调整模块151(见图3)，该光路调整模块151可以依据光接收功率(其例如可以通过与预设功率质量阈值(其例如可以是上面图2B中的第一功率质量阈值、第二功率质量阈值或第三功率质量阈值)进行比较，来评估自由光通信的质量，并且可以在光接收功率未达到该预设功率质量阈值时，优先调整主动端内的FSO设备/模块的光路/章动。这里，光路调整模块151可以包括前文所述的粗/精跟踪执行机构以及章动模块，从而可以进行光路校准/章动调整。从动端会跟随进行调整。在(反复)进行光路校准/章动调整之后，可能主动端处的光接收光功率达到该调节阶段的最优值，此时光接收功率会稳定在一定范围内无法提升。
2)进而，调整发射功率：主动端可以继续检测光接收功率，并判断是否达到了预设功率质量阈值，如果未满足，则可以通过图3中的自适应发射功率调节模块102来调整本端的光发射器件的发射功率，由此改变从动端的接收功率；从动端也会由于接收光功率出现调整变化，而驱动其内光发射器件的发射功率的调整。而当接收光功率明显超过所期望质量通信所需的功率时，则可以降低主动端或从动端的发射功率。
3)最后，调整收端灵敏度：主动端可以继续检测光接收功率，直到主动端内的光发射器件的发射功率已调至最大，仍然无法满足预定通信质量功率的要求，这表明链路状况比较差，此时可以启动两端网络设备/模块的光接收灵敏度调整，来提高光接收灵敏度。虽然，提高光接收灵敏度可能会导致速率降低，但这可以保障链路的预定通信质量或仍然可通。上述光接收灵敏度例如可以通过图3中的灵敏度自适应调整模块105来调整。
尽管上面按照1)→2)→3)的顺序描述了这3个环节的联调，但应当理解，这仅仅是示例。在其他实施例中，也可能以其他顺序来实现这3个环节的联调。在又一些其他实施例中，可能实现可调整发端功率的更多环节或更少环节的联调。在又一些实施例 中，可以仅针对其中一个环节进行功率自适应调整。
为了更加清楚地展示本公开是如何基于各种不同功率质量阈值来进行发端功率的自适应功率调整，图4B示出了更为详尽的系统性自动联调的示例实施例的流程图。
如图4B所示，可以在框410，进行收端的光接收功率的功率检测，然后可以依据所接收的光接收功率(其例如可以与第一功率质量阈值进行比较)，来评估自由光通信质量，并且可以在光接收功率未达到正常通信质量的功率阈值(例如第一功率质量阈值)时，在框411，优先调整主动端内的FSO设备/模块的光路/章动。同时，可以在框412，继续进行光接收功率的检测，如果在框413，发现光接收功率可以继续提升，则返回框411继续进行FSO设备/模块的光路/章动调整，否则在框414，进行收端和发端的发射功率调整。
接着，在框415，继续进行光接收功率的检测，并且在框416，判断光接收功率是否超过正常通信功率质量阈值(例如第一功率质量阈值)，如果未超过，则在框419，判断发射功率是否已经调整至最大值；如果超过，则在框417，判断光接收功率是否超过保障高质量通信的功率阈值(例如第三功率质量阈值)。一旦未超过例如第三功率质量阈值，则返回框414继续进行发射功率的调整，例如进一步增加发射功率，否则在框418，判断光接收功率是否超过指示超过过高的功率阈值(例如第四功率质量阈值)。如果是，则也返回框414，对发射功率进行调整，例如减小发射功率。
如果在框419，判断发射功率未调整至最大值，则可以返回至框414，进一步增大发射功率。反之，如果在框419，一旦判断发射功率已经调整至最大值，则在框420，进一步判断光接收功率是否达到无法保障基本通信的功率阈值(例如第二功率质量阈值)。如果是，则在框421，进行光模块的调整，也即灵敏度的调整，例如可以从低光接收灵敏度调整到高光接收灵敏度。在框422，继续进行接收光功率的检测，并且在框423，判断光接收功率是否回归到正常通信的功率阈值(例如第一功率质量阈值)，如果否的话，则返回框421，进一步进行光模块(或灵敏度)的调整，譬如可以进一步调高灵敏度(如果可以的话)。虽然在图4B中未示出，但还可以理解，如果在框423，判断光接收功率回归到了正常通信的功率阈值(例如第一功率质量阈值)以上，则可以选择性地进一步判断光接收功率是否超过保障高质量通信的功率阈值(例如第三功率质量阈值)，如果是，则可以返回至框421，对光模块(或灵敏度)进行调整，例如调回至低光接收灵敏度。
应当理解，上面图4B中的结合不同功率质量阈值进行功率自适应调整的方式仅仅是示例，在其他实施例中，可以依据更多或更少的功率质量阈值来进行功率自适应调整；又或者，可以以与图4B所示的结合功率质量阈值有所不同的方式来进行功率的自适应调整。
实施例3：基于单端闭环反馈的灵敏度自适应调整子方案
在上述实施例1和实施例2中，均可以实现灵敏度的自适应调整。该实施例3的方案可以是实施例1和2中的关于灵敏度自适应调整的子方案。
该实施例3的子方案的构思在于：针对FSO通信系统网络设备/模块的光模块无法自适应调整灵敏度的问题，本子方案在接收光功率严重劣化时，可以通过切换光模块，以保障链路仍可通；而当环境条件恢复时，切回原模块。
仍然，如前面所述的，可以将两端FSO通信系统区分为主动端和从动端，主动端先进行光模块的调整，而从动端根据主动端的变化来跟随调整。
图5示出了该实施例3的示例性架构布置。如图5所示，前文所述的灵敏度自适应调整模块105可以包括灵敏度自适应的接收(或发送)模块。仅作为示例，在主动端中，灵敏度自适应接收(或发送)模块107、106可以进一步包括高灵敏度和低灵敏度接收(或发送)模块111、切换模块108、协商模块109和光模块自适应调整模块110；在从动端中，灵敏度自适应的接收(或发送)模块207、206可以包括高灵敏度和低灵敏度接收(或发送)模块211、切换模块208、协商模块209和光模块自适应调整模块210。在一些实施例中，主动端10中的灵敏度自适应的接收(或发送)模块107、106可以与从动端20中的灵敏度自适应的接收(或发送)模块207、206相同或不同。在上述布置中，光模块自适应调整模块110适于接收来自接收光功率检测模块103所检测的光接收功率，并且适于基于该光接收功率(例如，由此评估自由光通信质量)，而自适应地经由切换模块109在高、低灵敏度接收模块111之间进行切换，以由此调整光接收灵敏度，从而调整主动端的发端功率。
高、低灵敏度光接收(或发送)模块107、106或者207、206可以是由两个独立模块封装而成，也可以是一个硬件模块通过编码等算法层面的调整来实现灵敏度的调整，同时还可以是一切具备灵敏度可调整功能的光模块，在此不对其实现方式进行限制。此外，光模块灵敏度的档次不限于两种，也可以更多。
该实施例3的子方案的工作流程如下：
主动端10探测接收光功率，当功率小于预定质量通信的功率阈值(例如，保障正常通信的第一功率质量阈值，或仅能保障基本通信(或低质量通信)的第二功率质量阈值，或保障高质量通信的第三功率质量阈值时)，灵敏度自适应调整模块中的光模块自适应调整模块110可以经由切换模块108而驱动本端的接收模块从低灵敏度切换至高灵敏度，例如从低灵敏度接收模块切换至高灵敏度接收模块。
从动端20的灵敏度自适应发送模块206与主动端的灵敏度自适应接收模块107可以通过协商模块109、209进行协商，并跟随、切换灵敏度。
接收光功率检测模块103持续检测光接收功率，在一些实施例中，当发现光接收功率恢复至较高水平(在接收模块灵敏度相对较低的情况下，仍有高质量通信)，则两端可以开始启动回调机制，从高灵敏度接收(发送)模块切回低灵敏度接收(发送)模块。
通过该实施例3，可以实现高、切换灵敏度的灵活切换，以便更好地应对不同的环境。
实施例4：基于单端跨设备/模块的功率反馈的自适应FSO光路/章动校准子方案
在上述基于功率反馈的架构级系统性自动联调方案的实施例2中，需通过光接收功率进行FSO光路/章动的校准。在FSO通信系统中(尤其是分体式FSO通信系统)，网络设备/模块和FSO设备/模块往往都具备接收功率探测功能，存在设计冗余问题。
该实施例4的构思在于：可以将网络设备/模块的接收光功率探测模块103或者FSO设备/模块的接收光功率探测模块(未标示)复用，以将检测的光功率反馈给FSO设备/模块内的粗/精跟踪执行机构或章动模块，进行光路或章动的调整。需要注意的是，本子方案重点在于接收光功率探测模块，而不限制计算模块的集成方式，该计算模块例如可以用作前面所提及的自适应发射功率调节模块102、灵敏度自适应调整模块105、或光路 调整模块151或者构成这些模块102、105、151的一部分。又或者，该计算模块可以独立于这些模块102、105、151而存在，但向这些模块102、105、151提供额外的计算功能。
作为示例，图6A示出了在网络设备/模块100的接收光功率探测模块103复用的情况下，计算模块215可以内置于FSO设备/模块200内的布置；图6B示出了在网络设备/模块100的接收光功率探测模块103复用的情况下，计算模块215可以内置于网络设备/模块100内的布置；以及图6C示出了在网络设备/模块100的接收光功率探测模块103复用的情况下，计算模块215可以外置于FSO设备/模块200和网络设备/模块100两者的布置。将会理解，在一些实施例中，计算模块215结合粗/精跟踪执行结构可以构成前面所提及的自适应功率调节模块，例如光路调整模块。在图7示出了在网络设备/模块100的接收光功率探测模块103复用的情况下，其光检测功率反馈至章动模块216的布置，其中章动模块216也可以视为前面所提及的自适应功率调节模块，例如光路调整模块或光路调整模块的一部分。
从以上描述可知，在上述实施例1-4中，实现了基于本端(例如，主动端)接收功率反馈(单端闭环反馈)的无需额外管理通道的本端的光发射器件的发射功率调整、光接收灵敏度调整或FSO光路/章动调整，并且可以同时实现三个环节的自动联调。此外，还可以实现对端(例如，从动端)的跟随调整。
下面将参照实施例5-8来描述利用额外的管理通道来实现自适应发端功率调整的相关技术。
第二实施方式：基于额外管理通道下的功率自适应调整方案
该第二实施方式与前面的第一实施方式的不同在于：在该实施方式中，存在额外管理通道。可以理解，该第二实施方式是第一实施方式在具有额外管理通道下的变型实施例。因此，在不互相矛盾的情况下，上面关于第一实施方式的描述可以适用于第二实施方式。同样地，第二实施方案可以具有多个实施例。在不互相矛盾的情况下，这些实施例同样地可以任意组合，并且可以与第一实施方式中的实施例相组合，它们的组合均在本公开的精神和范围之内，在下文中，将简要描述第二实施方式的各个实施例
实施例5：基于对端功率反馈的功率自适应调整方案
与实施例1相比，该实施例5的不同在于：FSO链路两端的FSO系统的发端功率自适应调整可以基于对端的光接收功率来执行，其中对端可以通过管理通道将光接收功率情况同步给本端。
图8示出了基于对端功率反馈的功率自适应调整方案的示意性布置。如图8所示，其示出了作为本端的FSO通信系统内的网络设备/模块100和作为对端的另一FSO通信系统内的网络设备/模块200。与图2A不同，图8中的网络设备/模块100可以包括发送端口101、接收端口104、自适应调节光功率模块102、接收光功率获取模块122和管理通道121，其中接收光功率获取模块122集成了本端的接收功率探测模块和用于对端的接收功率同步模块，后者可通过管理通道获得对端的接收功率信息。
因此，在工作中，可以仅基于对端的光接收功率来执行对本端的发端功率的调整。在又一些实施例中，可以借助于本端的光接收功率和对端的光接收功率两者来执行对本端的光发射器件的发端功率的调整。显然，借助于对端反馈的光接收功率可以更加清楚地了解本端和对端之间的自由光通信的链路的状况。
实施例6：基于双端功率反馈的架构级系统性自动联调方案
该实施例6的自动联调方案与实施例2的自动联调方案不同在于：在实施例6中，前面所提及的自动联调所涉及的三个环节中的对本端(例如，主动端)的光发射器件的发射功率调整可以结合对端(例如，从动端)的光接收功率反馈进行调整，而光接收灵敏度调整或FSO光路/章动调整两者可以仍采用本端(例如，主动端)的光接收功率反馈调整。
图9示出了基于双端功率反馈的系统性自动联调的示例性布置。图9与图3的布置不同在于：1)增加了管理通道121(如可用Wi-Fi、移动网络等)；2)使用集成了本端的接收光功率探测模块和对端的接收功率同步模块两者的接收光功率获取模块122，来代替图3中的接收光功率探测模块103，该接收光功率获取模块122可通过管理通道121获得对端的光接收功率信息。
借助于上述管理通道121，在该实施例中，对本端(例如主动端)的光发射器件的发射功率调整环节以及光接收灵敏度调整环节两者可以有如下变化，譬如：
●对本端的光发射器件的发射功率调整环节：其可以基于对端反馈的光接收功率来执行，其中本端可以经由管理通道将光接收功率的情况反馈(同步)给对端。也就是说，可以通过对端反馈的光接收功率来评估本端和对端之间的自由光通信质量。显然，借助于对端反馈的光接收功率可以更加清楚地了解本端和对端之间的自由光通信的链路的状况。
●光接收灵敏度调整环节：其可以仍然基于本端(例如，主动端)的接收功率来执行，但可以考虑去除实施例3中的协商模块。这是因为本实施例可以利用管理通道121将本端的灵敏度调整信息同步/反馈给对端，故协商模块不是必要的。
实施例7：基于本端功率反馈的灵敏度自适应调整(不含协商模块)
该实施例7与实施例3的不同在于：该实施例7虽然基于本端的接收功率来执行灵敏度的自适应调整，但去除了协商模块；本端的灵敏度调整信息通过管理通道被同步给对端。
图10示出了基于本端功率反馈的灵敏度自适应调整的示例性布置。相对于图5，图10中增加了管理通道121，同时去除了协商模块。
注意，尽管在该实施例中去除了协商模块，但这并非限制。在该实施例的变型中，协商模块和管理通道121两者可以同时保留，在这种情况下，本领域技术人员可以选择通过协商模块或管理通道之一来反馈或同步本端或对端的灵敏度调整信息。
以上详细地描述本公开的灵敏度自适应调整的实施方式及其实施例。下面将通过方法流程的方式来概要地描述本公开的FSO通信系统可以实现的各个技术方案。
图11示出了根据本公开的示例实施例在自由空间光(FSO)通信系统内操作的功率自适应调节方法的流程图，其中该FSO通信系统适于与另一FSO通信系统进行自由光通信，其中所述FSO通信系统可以视为第一端，所述另一FSO通信系统可以视为为第二端。该方法可以包括在第一端执行的以下操作：
在框1110，以初始发端功率向所述第二端发送第一光信号。在一些实施例中，第一端可以为主动端，第二端可以为从动端。该步骤可以通过发送端口来执行。因此，第一端可以经由发送端口主动地以初始发端功率向从动端发送作为自由光通信信号的第一光 信号。
在框1120，接收来自所述第二端的第二光信号。该步骤可以通过接收端口来执行。
在框1130，检测所述第二光信号的光功率，以作为所述第一端的光接收功率。该步骤可以通过接收光功率检测模块来执行。作为示例，该接收光功率接收模块可以在FSO通信系统内的网络设备/模块中，但这并非限制，在其他实施例中，该接收光功率接收模块在FSO通信系统内的FSO设备/模块中也是可能的。
在框1140，基于所述第一端的光接收功率，自适应地调整所述第一端的发端功率。如前所述，FSO通信系统的空间链路具有如下特性：当空间链路受天气等外界因素影响时，两端的光接收功率同增同减，具有对称性，因此可以通过本端的光接收功率来评估或推算对端的接收功率，从而驱动本端的发端功率的调整，由此实现免额外管理链路的自适应发端功率调整。
在一些实施例中，第一端的光接收功率可以与预设功率质量阈值(例如，前面所提及的第一、第二或第三功率质量阈值)进行比较，来评估第一端和第二端之间的自由光通信质量。
譬如，在一些实施例中，响应于所述第一端的光接收功率低于预设功率质量阈值，第一端例如可以自适应地增加所述第一端的发端功率。
在又一些实施例中，响应于所述第一端的光接收功率低于预设功率质量阈值，第一端可以自适应地对所述第一端内的光路(例如FSO内的光路)进行调整。更进一步的，该光路调整例如可以包括对第一端内的光纤耦合进行章动调整，以提高所述光纤的耦合效率。将会理解，通过调整光路的方式，可以以减少链路插损的方式来提高第一端的发端功率。
在又一些实施例中，响应于以光路调整方式而无法使得所述第一端的发端功率提升，第一端可以自适应地增加所述第一端中的光发射器件的发射功率。更进一步地，响应于所述光发射器件的发射功率无法增加，第一端可以自适应地对第一端的光接收灵敏度进行调整。以这种方式，实际上实现了基于单端闭环反馈的架构级系统性自动联调。这自动联调方式尤其可以适用于更为复杂的链路状况。
在又一些实施例中，响应于第一端的光接收功率低于预设功率质量阈值，所述第一端可以自适应地对第一FSO通信系统的光接收灵敏度进行调整，例如从低光接收灵敏度切换至高光接收灵敏度。
在又一些实施例，响应于所述第一端的光接收功率低于第一预设功率质量阈值，所述第一端可以自适应地从低光接收灵敏度切换至高光接收灵敏度，或者响应于所述第一端的光接收功率高于第二预设功率质量阈值，所述第一端可以自适应地从高光接收灵敏度切换至低光接收灵敏度，其中第二预设功率质量阈值大于第一预设功率质量阈值。仅作为示例，第一预设功率质量阈值例如可以是上面所描述的第一功率质量阈值、第二功率质量阈值或第三功率质量阈值，而第二预设功率质量阈值例如可以是上面所描述的第一功率质量阈值、第三功率质量阈值或第四功率质量阈值，其中第一预设功率质量阈值要求大于第二预设功率质量阈值。
在又一些实施例中，第一端可以经由自由光通信与第二端进行协商，并且依据协商结果对第一端的光接收灵敏度进行调整。
在又一些实施例中，自适应地调整所述第一端的发端功率还可以包括：接收来自所述第二端的接收光功率信息；以及基于所述接收光功率信息和所述第一端的光接收功率 两者，来自适应地调整所述第一端的发端功率。上述接收来自所述第二端的接收光功率信息例如可以包括经由FSO链路之外的链路来接收所述第二端的所述接收光功率信息。
在框1150，以经调整的发端功率向所述第二端发送第三光信号。
实际上，FSO通信系统在功率自适应的调节过程中会持续(或反复)执行框1110至框1140中的步骤，以便将发端功率调整到可保障预定质量通信(譬如高质量通信)的功率阈值。因此，该方法还可以包括：在以调整后的发端功率发送第三光信号之后，接收来自所述第二端的第四光信号；检测所述第四光信号的光功率，以作为所述第一端的更新的光接收功率；基于所述第一端的更新的光接收功率，自适应地调整所述第一端的发端功率；以及以经调整的发端功率向所述第二端发送第五光信号。在此不再赘述。
图12示出了根据本公开的另一示例实施例的自由空间光(FSO)通信系统内操作的功率自适应调节方法的流程图，其中FSO通信系统适于与另一FSO通信系统进行自由光通信，其中所述FSO通信系统可以视为第二端，所述另一FSO通信系统可以视为第一端。将会理解，在一些实施例中，第一端可以为主动端，第二端可以为从动端。该方法涉及在作为从动端的第二端执行的以下操作：
在框1210，在第一时间接收来自第一端的第一光信号。
在框1220，检测所述第一光信号的光功率，以作为所述第二端的第一光接收功率；
在框1230，在第二时间接收来自所述第一端的第二光信号；
在框1240，检测所述第二光信号的光功率，以作为所述第二端的第二光接收功率；
在框1250，基于所述第二光接收功率与所述第一光接收功率的比较结果，自适应地调整所述第二端的发端功率。
应当理解，在该实施例中，第二端作为从动端，其发端功率的调整可以跟随主动端的发端功率的调整而调整。尽管这里未详细描述，但应当理解，自适应地调整所述第二端的发端功率包括对第二端的光路进行调整，对第二端内的光发射器件的发射功率的调整，以及对第二端内的光接收灵敏度的调整。上面描述的对第一端的调整方式这里同样地适用于对第二端的调整。例如，在第二端(或从动端)，这三个环节的调节可以基于所述第二光接收功率与所述第一光接收功率的比较结果而单独进行，或者可以如第一端的联调那样进行，也就是说：优先进行对第二端的光路进行调整；然后在发端功率无法提升时，进行第二端内的光发射器件的发射功率的调整，以及在发射功率达到最大后，进行光接收灵敏度的调整。
在一些实施例中，对第二端进行光接收灵敏度的调整，可以基于与第一端的协商结果进行。在又一些实施例中，对第二端进行光接收灵敏度的调整包括从低光接收灵敏度调整到高光接收灵敏度，或者从高光接收灵敏度调整到低光接收领域度。
图13示出了根据本公开的又一示例实施例的自由空间光(FSO)通信系统内操作的功率自适应调节方法的流程图，其中FSO通信系统包括彼此自由光通信的第一FSO通信系统和第二FSO通信系统，所述第一FSO通信系统可以视为第一端，所述另二FSO通信系统可以视为第二端。该方法可以包括：
在框1310，第一端以初始发端功率向所述第二端发送第一光信号；
在框1320，第二端检测所述第一光信号的光功率，以作为所述第二端的第一光接收功率；
在框1330，第二端向所述第一端发射第二光信号；
在框1340，第一端检测所述第二光信号的光功率，以作为第二光接收功率；
在框1350，第一端基于所述第二光接收功率，自适应地调整所述第一端的发端功率；
在框1360，第一端以经调整的发端功率向所述第二端发送第三光信号；
在框1370，第二端检测所述第三光信号的光功率，以作为第三光接收功率；以及
在框1380，基于所述第三光接收功率与所述第一光接收功率的比较结果，第二端自适应地调整所述第二端的发端功率。
从以上的操作可知，第一端可以作为主动端，第二端可以作为从动端。该方法可以实现第一端和第二端的发端功率的联动调整。由于上面已经对第一端和第二端的发端功率如何进行调整已经进行了详细的描述，这里不再赘述。
以上已经详细地介绍本公开的各个实施例的实现方案。将会理解，本公开可以实现免额外管理链路通道的自适应功率调整和架构级的自动联调，这提升了FSO通信系统的整体可通率。具体而言：
对于1)基于单端闭环反馈的功率自适应方案而言，其可以实现FSO系统发端功率的自适应调整，有利于降低安装调测的工程实施难度，提高系统对各种环境及变化的适应能力，尤其在环境劣化时，仍能保持较高的可通率。另外，可以充分利用FSO通信空间链路的特性，减少自适应发送功率调整对额外管理链路的需求。
对于2)基于功率反馈的架构级系统性自动联调方案(包括：单端闭环反馈或双端功率反馈结合)而言，其可以根据环境的劣化程度，逐渐降级，提高系统链路整体可通率，例如：在链路状态较好时，保障高链路质量；在链路状态劣化时，保障链路基本可通。另外，可以实现自动化调整，减少人工维护成本。
对于3)基于功率反馈的光模块灵敏度自适应调整(包括：有协商模块和无协商模块)而言，其在链路状态较好时，可自适应选择低灵敏度光模块，保障高质量通信；而在链路状态劣化时，可自适应切换高灵敏度光模块，保障链路基本可通。
对于4)基于跨设备功率反馈的自适应FSO光路/章动校准而言，其可以充分复用网络设备的功率探测功能，简化FSO设备设计(尤其对于网络设备与FSO设备分离部署，FSO设备越小越好)。另外，网络设备与FSO设备的联动，可以共同优化链路插损。
以上已经详细地描述本公开的波长交换方法的流程。将会理解，上面描述的流程仅仅是示例。尽管说明书中以特定的顺序描述了方法的步骤，但是这并非要求或者暗示必须按照该特定顺序来执行这些操作，或是必须执行全部所示的操作才能实现期望的结果，相反，描绘的步骤可以改变执行顺序。附加地或备选地，可以省略某些步骤，将多个步骤合并为一个步骤执行，和/或将一个步骤分解为多个步骤执行。
虽然已经在附图和前述描述中详细说明和描述了本发明，但这些说明和描述应被认为是说明性的或示例性的而不是限制性的；本发明不限于所公开的实施例。本领域技术人员在实践所请求保护的发明中，通过研究附图、公开和所附权利要求可以理解并且实践所公开的实施例的其它变体。
在权利要求中，词语“包括”并不排除其它元件，并且不定冠词“一”或“一个”不排除多个。单个元件或其它单元可以满足在权利要求中阐述的多个项目的功能。仅在互不相同的实施例或从属权利要求中记载某些特征的仅有事实，并不意味着不能有利地使用这些特征的组合。在不脱离本申请的精神和范围的情况下，本申请的保护范围涵盖在各个实施例或从属权利要求中记载的各个特征任何可能组合。
此外，在权利要求中的任何参考标记不应被理解为限制本发明的范围。

Claims (26)

  1. 一种功率自适应调节方法，包括：
    第一自由空间光FSO通信系统以初始发端功率向适于与所述第一FSO通信系统进行自由光通信的第二FSO通信系统发送第一光信号；
    所述第一FSO通信系统接收来自所述第二FSO通信系统的第二光信号；
    所述第一FSO通信系统检测所述第二光信号的光功率，以作为所述第一FSO通信系统的光接收功率；
    所述第一FSO通信系统基于所述第一FSO通信系统的光接收功率，自适应地调整所述第一FSO通信系统的发端功率；以及
    所述第一FSO通信系统以经调整的发端功率向所述第二FSO通信系统发送第三光信号。
  2. 根据权利要求1所述的功率自适应调节方法，其中自适应地调整所述第一FSO通信系统的发端功率包括：
    响应于所述第一FSO通信系统的光接收功率低于预设功率质量阈值，所述第一FSO通信系统自适应地增加所述第一FSO通信系统的发端功率。
  3. 根据权利要求1所述的功率自适应调节方法，其中自适应地调整所述第一FSO通信系统的发端功率包括：
    响应于所述第一FSO通信系统的光接收功率低于预设功率质量阈值，所述第一FSO通信系统自适应地增加所述第一FSO通信系统中的光发射器件的发射功率。
  4. 根据权利要求1所述的功率自适应调节方法，其中自适应地调整所述第一FSO通信系统的发端功率包括：
    响应于所述第一FSO通信系统的光接收功率低于预设功率质量阈值，所述第一FSO通信系统自适应地对所述第一FSO通信系统内的光路进行调整。
  5. 根据权利要求4所述的功率自适应调节方法，其中自适应地对所述第一FSO通信系统内的光路进行调整包括：
    对所述第一FSO通信系统内的光纤耦合进行章动调整，以提高所述光纤的耦合效率。
  6. 根据权利要求4所述的功率自适应调节方法，其中自适应地调整所述第一FSO通信系统的发端功率还包括：
    响应于以光路调整方式而无法使得所述第一FSO通信系统的所述光接收功率提升，所述第一FSO通信系统自适应地增加所述第一FSO通信系统中的光发射器件的发射功率。
  7. 根据权利要求6所述的功率自适应调节方法，其中自适应地调整所述第一FSO通信系统的发端功率还包括：
    响应于所述光发射器件的发射功率无法增加，则所述第一FSO通信系统自适应地对所述第一FSO通信系统的光接收灵敏度进行调整。
  8. 根据权利要求1所述的功率自适应调节方法，其中自适应地调整所述第一FSO通信系统的发端功率包括：
    响应于所述第一FSO通信系统的光接收功率低于预设功率质量阈值，所述第一FSO通信系统自适应地对所述第一FSO通信系统的光接收灵敏度进行调整。
  9. 根据权利要求1所述的功率自适应调节方法，其中自适应地调整所述第一FSO通信系统的发端功率包括：
    响应于所述第一FSO通信系统的光接收功率低于预设功率质量阈值，所述第一FSO通信系统经由自由光通信与所述第二FSO通信系统进行协商；以及
    基于所述协商结果，对所述第一FSO通信系统的光接收灵敏度进行调整。
  10. 根据权利要求1所述的功率自适应调节方法，其中自适应地调整所述第一FSO通信系统的发端功率包括：
    响应于所述第一FSO通信系统的光接收功率低于第一预设功率质量阈值，所述第一FSO通信系统自适应地从低光接收灵敏度切换至高光接收灵敏度；或
    响应于所述第一FSO通信系统的光接收功率高于第二预设功率质量阈值，所述第一FSO通信系统自适应地从高光接收灵敏度切换至低光接收灵敏度，其中第二预设功率质量阈值大于第一预设功率质量阈值。
  11. 根据权利要求1所述的功率自适应调节方法，还包括：
    在以调整后的发端功率发送第三光信号之后，接收来自所述第二FSO通信系统的第四光信号；
    检测所述第四光信号的光功率，以作为所述第一FSO通信系统的更新的光接收功率；
    基于所述第一FSO通信系统的更新的光接收功率，自适应地调整所述第一FSO通信系统的发端功率；以及
    以经调整的发端功率向所述第二FSO通信系统发送第五光信号。
  12. 根据权利要求1所述的功率自适应调节方法，其中自适应地调整所述第一FSO通信系统的发端功率还包括：
    接收来自所述第二FSO通信系统的接收光功率信息；以及
    基于所述接收光功率信息和所述第一FSO通信系统的光接收功率两者，来自适应地调整所述第一FSO通信系统的发端功率。
  13. 根据权利要求12所述的功率自适应调节方法，其中接收来自所述第二FSO通信系统的接收光功率信息包括：
    经由FSO链路之外的链路来接收所述第二FSO通信系统的所述接收光功率信息。
  14. 一种功率自适应调节方法，包括：
    第二自由空间光FSO通信系统在第一时间接收来自适于与所述第二FSO通信系统进行自由光通信的第一FSO通信系统的第一光信号；
    所述第二FSO通信系统检测所述第一光信号的光功率，以作为所述第二FSO通信系统的第一光接收功率；
    所述第二FSO通信系统在第二时间接收来自所述第一FSO通信系统的第二光信号；
    所述第二FSO通信系统检测所述第二光信号的光功率，以作为所述第二FSO通信系统的第二光接收功率；
    所述第二FSO通信系统基于所述第二光接收功率与所述第一光接收功率的比较结果，自适应地调整所述第二FSO通信系统的发端功率。
  15. 一种在通信系统内操作的功率自适应调节方法，所述通信系统包括彼此自由光通信的第一自由空间光FSO通信系统和第二FSO通信系统，所述方法包括：
    所述第一FSO通信系统以初始发端功率向所述第二FSO通信系统发送第一光信号；
    所述第二FSO通信系统检测所述第一光信号的光功率，以作为所述第二FSO通信系统的第一光接收功率；
    所述第二FSO通信系统向所述第一FSO通信系统发射第二光信号；
    所述第一FSO通信系统检测所述第二光信号的光功率，以作为第二光接收功率；
    所述第一FSO通信系统基于所述第二光接收功率，自适应地调整所述第一FSO通信系统的发端功率；
    所述第一FSO通信系统以经调整的发端功率向所述第二FSO通信系统发送第三光信号；
    所述第二FSO通信系统检测所述第三光信号的光功率，以作为第三光接收功率；以及
    基于所述第三光接收功率与所述第一光接收功率的比较结果，所述第二FSO通信系统自适应地调整所述第二FSO通信系统的发端功率。
  16. 一种第一自由空间光FSO通信系统，包括：
    发送端口，其适于以初始发端功率向适于与所述第一FSO通信系统进行自由光通信的第二FSO通信系统发送第一光信号；
    接收端口，其适于接收来自所述第二FSO通信系统的第二光信号；
    接收光功率检测模块，其适于检测所述第二光信号的光功率，以作为所述第一FSO通信系统的光接收功率；以及
    自适应功率调节模块，其适于基于所述第一FSO通信系统的光接收功率，自适应地 调整所述第一FSO通信系统的发端功率；
    其中所述发送端口还适于以经调整的发端功率向所述第二FSO通信系统发送第三光信号。
  17. 根据权利要求16所述的FSO通信系统，所述自适应功率调节模块包括：
    自适应发射功率调节模块，其适于在所述第一FSO通信系统的光接收功率低于预设功率质量阈值时，自适应地调整所述第一FSO通信系统内的光发射器件的发射功率。
  18. 根据权利要求16所述的FSO通信系统，所述自适应功率调节模块包括：
    光路调整模块，其适于在所述第一FSO通信系统的光接收功率低于预设功率质量阈值时，对所述第一FSO通信系统内的光路进行调整。
  19. 根据权利要求18所述的FSO通信系统，其中所述光路调整模块还包括章动模块，
    所述章动模块适于在所述第一FSO通信系统的光接收功率低于预设功率质量阈值时，对所述第一FSO通信系统内的光纤耦合进行章动调整，以提高光纤耦合的效率。
  20. 根据权利要求16所述的FSO通信系统，所述自适应功率调节模块包括：灵敏度自适应调整模块，
    所述灵敏度自适应调整模块适于在所述第一FSO通信系统的光接收功率低于预设功率质量阈值时，自适应地调整所述第一FSO通信系统的光接收灵敏度。
  21. 根据权利要求16所述的FSO通信系统，其中自适应地调整所述第一FSO通信系统的发端功率包括：
    响应于所述第一FSO通信系统的光接收功率低于预设功率质量阈值，所述自适应功率调节模块自适应地增加所述第一FSO通信系统的发端功率。
  22. 根据权利要求20所述的FSO通信系统，所述灵敏度自适应调整模块还包括：
    协商模块，所述协商模块适于在所述第一FSO通信系统的光接收功率低于预设功率质量阈值时，自适应地经由自由光通信与所述第二FSO通信系统进行协商，以确定所述第一FSO通信系统的光接收灵敏度；
    切换模块，其适于基于所协商的所述第一FSO通信系统的光接收灵敏度而在不同的光接收灵敏度之间进行切换。
  23. 根据权利要求16所述的FSO通信系统，其中所述自适应功率调节模块还被配置成：
    响应于所述第一FSO通信系统的光接收功率低于预设功率质量阈值，则首先使用光路调整模块对所述第一FSO通信系统内的光路进行调整；
    响应于所述光路的调整无法使得所述第一FSO通信系统的发端功率得以提升，则使用自适应发射功率调节模块来自适应地增加所述第一FSO通信系统中的光发射器件的发射功率；以及
    响应于所述光发射器件的发射功率无法增加，则使用灵敏度自适应调整模块来自适应地对所述第一FSO通信系统的光接收灵敏度进行调整。
  24. 根据权利要求18所述的FSO通信系统，还包括：管理通道，所述第一FSO通信系统适于经由所述管理通道以自由光通信之外的通信链路，接收来自所述第二FSO通信系统的接收光功率信息，
    所述自适应功率调节模块适于基于所述接收光功率信息和所述第一FSO通信系统的光接收功率两者，来自适应地调整所述第一FSO通信系统的发端功率。
  25. 一种第二自由空间光FSO通信系统，包括：
    接收端口，其适于在第一时间接收来自适于与所述第二FSO通信系统进行自由光通信的第一FSO通信系统的第一光信号，以及在第一时间之后的第二时间接收来自所述第一FSO通信系统的第二光信号；
    接收光功率检测模块，其适于检测所述第一光信号的光功率，以作为所述第二FSO通信系统的第一光接收功率，以及检测所述第二光信号的光功率，以作为所述第二FSO通信系统的第二光接收功率；
    自适应功率调节模块，其适于基于所述第二光接收功率与所述第一光接收功率的比较结果，自适应地调整所述第二FSO通信系统的发端功率；
    发送端口，其适于以经调整的发端功率来向所述第一FSO通信系统发送光信号。
  26. 一种通信系统，包括彼此进行自由光通信的根据权利要求16-24中任一项所述的第一自由空间光FSO通信系统和根据权利要求25所述的第二FSO通信系统。
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Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101841374A (zh) * 2009-03-20 2010-09-22 台达电子工业股份有限公司 光收发系统及调整其光收发器输出功率的方法
US20120263460A1 (en) * 2011-04-15 2012-10-18 Cisco Technology, Inc. Adaptive setting of transmit power in optical transceivers
CN106452603A (zh) * 2015-08-05 2017-02-22 谷歌公司 具有针对自由空间光通信中的闪烁补偿的闭环控制的光放大器
CN106506093A (zh) * 2016-11-28 2017-03-15 中车株洲电力机车研究所有限公司 一种fso通信系统

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101841374A (zh) * 2009-03-20 2010-09-22 台达电子工业股份有限公司 光收发系统及调整其光收发器输出功率的方法
US20120263460A1 (en) * 2011-04-15 2012-10-18 Cisco Technology, Inc. Adaptive setting of transmit power in optical transceivers
CN106452603A (zh) * 2015-08-05 2017-02-22 谷歌公司 具有针对自由空间光通信中的闪烁补偿的闭环控制的光放大器
CN106506093A (zh) * 2016-11-28 2017-03-15 中车株洲电力机车研究所有限公司 一种fso通信系统

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