• 专利附录
  • 专利说明
  • 权利要求
  • 类似技术
  • 同族专利
  • 引用文献
  • 法律状态
  • 优先权
    • 专利摘要:
    The present invention relates to a system and method for adjusting a radiation direction of an optical communication signal (20) between a communication platform (100) and a remote station ( 200). The method comprises the following steps: from a starting position of a beam deflection unit (140) of the communication platform for directing the optical communication signal, adoption of the deflection positions of the communication unit. beam deflection (140) along two different motion lines and in opposite directions along the motion lines, the deflection positions corresponding to deflection angles equal in value and each deflection position being maintained for a different period ; measuring an intensity of the optical communication signal at the remote station (200); as soon as an intensity variation of the optical communication signal is detected at the remote station (200), determining a signal quality variation of the optical communication signal and detecting the duration of this intensity variation ; determining the intensity variation that corresponds to the best signal quality variation and the associated duration; variation of the intensity of a conducting beam for the duration defined in the previous step.
    公开号:FR3076967A1
    申请号:FR1871691
    申请日:2018-11-22
    公开日:2019-07-19
    发明作者:Frank Heine
    申请人:Tesat Spacecom GmbH and Co KG；
    IPC主号:
    专利说明:

    The present invention relates to a system and method for adjusting a direction of radiation of an optical communication signal (20) between a communication platform (100) and a remote station (200). The method comprises the following steps: from a starting position of a beam deflection unit (140) of the communication platform serving to direct the optical communication signal, adoption of the deflection positions of the communication unit beam deflection (140) along two different lines of motion and in opposite directions along the lines of motion, the deflection positions corresponding to deflection angles equal in value and each deflection position being maintained for a different period ; measuring an intensity of the optical communication signal at the remote station (200); as soon as a variation in the intensity of the optical communication signal is detected at the remote station (200), determining a variation in signal quality of the optical communication signal and detecting the duration of this variation in intensity ; determination of the intensity variation which corresponds to the best variation in signal quality as well as the associated duration; variation of the intensity of a conducting beam for the duration defined in the previous step.
    410. /144+ 144- 146+ 146- V V ®-ί ···· | - ..... 1 — ί — s —.......— ; I’m r L '' 1 420:; ti ; ; : ¼: î ! 1 ...../ * ’ ; ; Q '' r ‘ /4> <; ; ; --- U ; ; * ‘ ; I; ; M :; ____________1. 1 JzlJ î
    t
    Description
    Title of the invention: "Beam alignment in unidirectional optical communication systems"
    Field of the Invention The present invention relates generally to the field of optical signal transmission, for example between a mobile platform and a remote station, in particular between a satellite and a remote station. The present invention relates in particular to a communication platform and a communication system with a communication platform and a remote station as well as a method for adjusting a direction of radiation of an optical communication signal between a communication platform and a remote station.
    STATE OF THE ART For laser communication units (also called "laser communication terminal", in English laser communication terminal, LCT), it is necessary to keep the alignment of the emitted beam stable with respect to the receiving direction or at the position of the distant station precisely for a longer period (from several minutes to several days). This is necessary in order to guarantee a good signal quality for the received signal for the remote station.
    The divergence of optical laser communication systems is generally a few tens of prad, but an error in alignment of the beam emitted relative to the beam received from a few prad quickly leads to significant losses on the transmission section. It is further necessary in mobile laser communication systems to slightly change the direction of the emitted laser with respect to the light received (from a few prad to a few hundred prad) to compensate for the effects of the travel time. This angle can be called compensation angle or bypass angle. This angle is generally known, but for longer transmission sections, it is actively adjusted (with a reduced bandwidth), thus avoiding additional losses on the transmission section. The direction of transmission generally deviates for a longer period (several minutes) from the direction of reception due to thermomechanical effects, even when it has been calibrated using suitable means before the establishment of the link.
    Documents DE 10 2012 012 898 A1 and EP 2 680 024 A3 describe a system and a method for determining the position of a communication platform in the form of a satellite.
    Aim of the invention [0006] Improving the alignment of an optical communication signal from a one-way communication platform can be considered as an objective.
    Description and advantages of the invention [0008] This objective is achieved due to the subject of the independent claims. Improvements appear from the dependent claims and from the following description.
    In one aspect, a communication platform is specified. The communication platform includes a transmitter, an intensity detector, a beam deflection unit, an actuator and a control unit. The transmitter is designed to produce an optical communication signal. The intensity detector is designed to detect the intensity of a conductive beam. The beam deflection unit is designed to direct the optical communication signal to a remote station. The actuator is designed to rotate the beam deflection unit around a point of rotation. The control unit is made to control the actuator. The control unit is additionally provided to control the actuator such that the optical communication signal is deflected by the beam deflection unit in a first direction along a first line of motion for a first period predefined and then deflected along the first line of movement in a second direction opposite to the first direction of the first line of movement for a second predefined period. The control unit is further provided to control the actuator such that the optical communication signal is then deflected by the beam deflection unit in a first direction along a second line of motion during a third predefined period and then deflected in a second direction opposite to the first direction of the second line of movement along the second line of movement for a fourth predefined period. The control unit is further provided for obtaining an intensity of the conductive beam detected by the intensity detector and for determining a direction of deflection of the beam deflection unit along the first line of movement or the second movement line based on the detected intensity and for shifting the beam deflection unit to a deflection position.
    The optical communication signal is in particular a laser signal and it is used to transmit information from the communication platform to a remote station. To determine a position of the remote station and be able to maintain it, the remote station emits a conductive beam which can use the communication platform to orient an optical system on the remote station.
    The transmitter produces the optical communication signal on the basis of a data stream to be transmitted. The optical communication signal is irradiated at the beam deflection unit and diverted from the beam deflection unit. The beam deflection unit is for example a flat element made so as to reflect the optical communication signal. Functionally, the beam deflection unit is therefore a mirror. The beam deflection unit is attached to a point of rotation and allows movement with at least two degrees of freedom. In particular, the beam deflection unit can pivot in two different directions. The movement of the beam deflection unit aligns the reflected optical communication signal on the remote station. The actuator is coupled in such a way to the beam deflection unit that a force can be transmitted to the beam deflection unit, so that the beam deflection unit is brought into a desired position.
    It is conceivable that the beam deflection unit has two beam deflection elements connected one behind the other. In this variant, each beam deflection element can pivot only in one direction and therefore has only one degree of freedom of rotation. However, the directions in which the two beam deflection elements can rotate or rotate differ from one another, so that an optical beam can be deflected in two different directions. Preferably, the directions of pivoting of the two beam deflection elements are perpendicular to each other.
    It is expected that the beam deflection unit is brought into different deflected positions from a starting position. The deflected positions are maintained for a predetermined defined period respectively. Preferably, the beam deflection unit is returned to the starting position after each deflected position.
    Preferably, the beam deflection unit is moved so that the optical communication signal is deflected in four different directions from the starting position. The sequence in which the deflection positions are taken is fixed and is not modified in an exemplary embodiment. This movement of the beam deflection unit allows the remote station to determine an influence of the change in direction of radiation of the optical communication signal on the signal quality at the receiver.
    Generally, a change in direction of radiation of the optical communication signal causes a variation in intensity or amplitude of the signal received at the remote station. If the optical communication signal is optimally aligned in the starting position of the beam deflection unit on the remote station (i.e. the optical communication signal meets a receiver with its strongest intensity ), each change of direction of radiation of the optical communication signal causes a drop in intensity or amplitude, that is to say a drop in signal quality at the level of the receiver. If however the optical communication signal is not optimally aligned in the starting position on the remote station (i.e. the maximum intensity of the emitted beam does not correspond to the aperture of reception system input), at least one deflection position brings the strength or amplitude of the received signal to a level higher than that of the starting position. This therefore means that the optical communication signal is very well received from the receiver even when it is not optimally aligned with the remote station. In this case, however, the optical communication signal does not have the highest possible intensity.
    The remote station detects the strength of the received signal. This is how we also detect variations in intensity. The distant station also determines the duration of a variation in the intensity of the received signal. If the remote station detects an improvement in signal quality, the duration of the improved signal quality is also known.
    As already described above, a defined duration or period is associated with each deflection position of the beam deflection unit, the period of a deflection position being different from the period of each other deflection position. It is thus possible to deduce, from the remote station, the deflection position causing an improved signal quality from the determination of the period of an improved signal quality.
    In other words, the beam deflection unit is therefore brought in for defined periods in different deflection positions and the remote station measures the associated variations in signal quality and the associated periods. The remote station then calculates whether the deflection position leads to an improvement in signal quality and determines the duration of the improved signal quality.
    To now transmit the information relating to the preferred deflection position to the communication platform, the remote station can vary the amplitude of the conductive beam for the duration of the period associated with the preferred deflection position. The communication platform can now measure the period of the modified intensity of the conductive beam and shift the beam deflection unit to the preferred deflection position. The preferred deflection position becomes the new starting position and the steps described here can be performed again.
    In an example, here is what is proposed: the first deflection position corresponds to a unit of time, the second deflection position corresponds to two units of time, the third deflection position corresponds to three units of time and the fourth deflection position corresponds to four time units. If the distant station now determines an improvement in signal quality for three time units, this means that the third deflection position is better than the starting position of the beam deflection unit. The remote station now models the conductive beam so that the amplitude of the conductive beam also increases to three units of time. For example, the amplitude of the conductive beam can be increased or reduced. The communication platform now has information indicating that the third deflection position induces better signal quality than the starting position and shifts the beam deflection unit to the third deflection position. From there, the beam deflection unit can again be shifted from the first to the fourth deflection position. The beam deflection unit can thus approach an optimal position in stages.
    The approach described here makes it possible to adjust the alignment of the beam deflection unit on a remote station. This approach describes in particular a fine adjustment in unidirectional communication arrangements. In the absence of a data link between the remote station and the communication platform, there is no return channel for transmitting to the communication platform the effect of the deflection positions on the signal quality of the remote station. This is resolved by varying the intensity of a conductive beam between the remote station and the communication platform and by allowing the communication platform to deduce from the duration of the changed intensity a preferred deflection position of the unit. beam deflection. It is noted that a conductive beam of optical communication link between a receiver and a transmitter for the purposes of this description is not considered to be a data channel.
    According to one embodiment, the control unit is designed to control the beam deflection unit so that the optical communication signal is deflected by the same value of angle of deflection along the first line of movement or the second line of movement during each deflection process.
    For example, the deflection angle can be 2 prad. Generally, the deflection angle is chosen so that a connection between the communication platform and the remote station is not interrupted or is interrupted. That is, the deflection angle is chosen to be small enough that the distant station is not in any deflection position outside the radiation cone of the optical communication signal. The deflection angle is notably less than the divergence of the optical communication signal.
    The deflection angle is defined for each deflection position from the starting position. This means that the deflection positions are arranged at a regular angular distance from the starting position.
    According to another embodiment, the first line of movement and the second line of movement extend in a linear fashion and cross each other at an angle of 90 °.
    This means that starting from the starting position, the optical communication signal is first moved to the left and then brought back to the starting position before being then moved to the right and again brought back into the starting position. This pattern is then repeated in the up and down directions. The two lines of movement are perpendicular to each other.
    According to another embodiment, each individual period among the second period, the third period and the fourth period is an integer multiple of the first period. In addition, each period is distinguished from each other period, that is to say that each period has an unequivocal duration.
    This allows the associated deflection position to be deduced only from the duration of a variation in signal quality.
    According to another embodiment, the transmitter is a laser source with a unique mode characteristic. However, it is also possible to use multimode laser sources.
    According to another embodiment, the control unit is designed to control the actuator so that the beam deflection unit is deflected according to a predefined sequence along the first line of movement in the first and the second direction and along the second line of movement along the first and second directions.
    This means that the sequence of the deflection positions of the beam deflection unit is known and must no longer be communicated separately to the remote station and must no longer be absolutely known by the remote station. It is much more sufficient that the communication platform makes available an association of the deflection position and the period. If the distant station notices an improvement in the signal quality and modulates the conductive beam for a defined period, the communication platform can determine this period and determine from its own association the associated deflection position of the deflection unit of beam. To this end, the communication platform can use an association table stored in a memory by the control unit.
    The control unit can for example be a computer comprising a processor and a memory. The processor is designed to execute coded instructions and the functions associated with the control unit. The processor can access memory here to store information in memory or read information from memory.
    The processor can be a microcontroller or a programmable logic gate (for example an EPGA, in English field programmable array array). The memory can be a volatile or fixed memory unit.
    According to another embodiment, the control unit is designed to control the actuator so that the beam deflection unit is brought into a starting position after each deflection process before taking the deflection position next.
    According to another embodiment, the communication platform is a satellite. Starting from the communication platform, one can establish a communication link with a remote station. The remote station may be another satellite, an aircraft, or a mobile or stationary remote station on the surface of the Earth.
    In another aspect, a communication system is presented. The combination system comprises a communication platform as mentioned above and described below and a remote station. The remote station is designed to emit the conductive beam towards the communication platform. The remote station is additionally designed to detect the differences in intensity of the optical communication signal as well as the duration of these differences in intensity and to determine the difference in intensity of the optical communication signal having the best signal quality as well. than the duration of this intensity gap. The remote station is additionally made to vary an intensity of the conductive beam for the duration of the intensity difference of the optical communication signal. The communication platform is designed to determine, on the basis of the duration of the intensity difference of the conductive beam, the deflection direction of the optical communication signal which corresponds to the duration of the intensity difference of the conductive beam .
    The communication platform can thus adjust a one-way optical transmission section to the remote station without the need for a data link from the remote station to the communication platform. On the contrary, the conducting beam leaving the distant station is used to signal to the communication platform, by a variation of the intensity of the conducting beam, which deflection position of the optical combination signal induces an improvement in the signal quality in the remote station.
    According to one embodiment, the communication platform is designed to deflect the beam deflection unit after reception of the difference in intensity of the conductive beam and to shift it to a target position.
    The target position corresponds to the deflection position producing the best signal quality in the remote station. From this target position, the beam deflection unit can again be moved to different deflection positions to find another possible improvement in signal quality.
    If the optical communication signal is already optimally aligned on the remote station, each deflection position causes lower signal quality. In such a case, the remote station can entirely forgo varying the intensity of the conductive beam. As a variant, the conducting beam can be modulated in a predetermined model making it possible to indicate to the communication platform that an additional change in the direction of radiation of the optical communication signal is not necessary.
    The steps performed to move the beam deflection unit from a starting position in order to reach the next starting position can be called adjustment steps. Each adjustment step provides for the beam deflection unit to be brought to different deflection positions from which one is chosen as the next starting position. Several such adjustment steps can be called an adjustment cycle. For example, an adjustment cycle may end when no further further improvement in signal quality can be achieved. An adjustment cycle may however also contain a predetermined fixed number of adjustment steps, for example five adjustment steps. An adjustment cycle can be repeated after several minutes to fine-tune the direction of radiation of the optical communication signal on the remote station.
    According to another embodiment, the communication platform is made to move the beam deflection unit along the first line of movement in the first direction (first deflection position) and then along the first line of movement in the second direction (second deflection position) as well as along the second line of movement in the first direction (third deflection position) and then along the second line of movement in the second direction (fourth position after deflection of the beam deflection unit into the target position, thereby determining an appropriate target position.
    This embodiment describes that several adjustment steps are carried out one after the other. An adjustment step starts from a starting position and ends at a target position of the beam deflection unit.
    In another aspect, a method of adjusting a direction of radiation of an optical communication signal between a communication platform and a remote station is provided. The method has the following steps: from a starting position of a beam deflection unit of the communication platform serving to direct the optical communication signal, deflection positions of the beam deflection unit are adopted along two different lines of movement and in opposite directions along the lines of movement, the deflection positions corresponding to deflection angles equal in value and each deflection position being maintained for a different period; measurement of an intensity of the optical communication signal at the remote station; as soon as a variation in the intensity of the optical communication signal is detected at the remote station, determining a variation in signal quality of the optical communication signal and detecting a duration of this variation in intensity; determination of the intensity variation which corresponds to the best variation in signal quality as well as the associated duration; variation of the intensity of a conducting beam for the duration defined in the previous step.
    The embodiments illustrated in relation to the communication platform and the communication system also apply to the method described here. This means that functions of the complication platform and the communication system can be implemented in the form of process steps.
    According to one embodiment, the method further comprises the following steps: detection, by the communication platform, of the duration of the variation in intensity of the conductive beam; and moving the beam deflection unit to the deflection position which has been adopted for the duration of the variation in intensity of the conductive beam.
    At this stage, the communication platform compares the duration of the variation of intensity of the conductive beam to the periods of the deflection positions. It is thus determined which deflection position led to the side of the distant station with the best signal quality. The beam deflection unit can then be moved to the next starting position for the next adjustment step.
    According to another embodiment, the process steps are repeated until one has determined along a first line of movement the deflection position of the beam deflection unit which corresponds to maximum signal quality.
    The beam deflection unit can for example be brought first, along the first line of motion (for example in the horizontal direction), to the point at which the signal quality is maximum. This point is determined in that a movement of the beam deflection unit in one direction firstly improves the signal quality, however the signal quality decreases again from a certain point. The position as it is before the signal quality decreases again corresponds to the maximum signal quality in the horizontal direction.
    According to another embodiment, the process steps are repeated until the deflection position of the beam deflection unit has been determined in a second line of motion, which corresponds to the quality of maximum signal.
    The procedure described above with respect to the first line of movement is also repeated for the second line of movement (in the vertical direction).
    Naturally, the beam deflection unit can also be adjusted in turn in the horizontal or vertical direction or in a sequence allowing the best change in signal quality.
    The approach set out here can be described differently as follows:
    An optical link with a beam limited in its diffraction is indicated on a signal from the remote terminal used for the alignment of its own reception system and transmission system. Even when the own system is not equipped for receiving data, it has a system called tracking system in English detecting, using a conductive beam, a deviation in reception direction relative to the expected direction of emission. Systems limited in their diffraction also include an adjustment mechanism (beam deflection unit and actuator) independent of the direction of reception for the angle of the outgoing beam (for example to adjust a bypass angle). It is characteristic for such systems that they detect the intensity differences and can analyze them. The approach presented here is based on an analysis of these intensities.
    The approach described here makes it possible to adjust in systems without a dedicated optical receiver the direction of radiation of the optical signal carrier. In particular, only the functions necessary for maintaining laser communication are used. The configuration of the time intervals and durations makes it possible to react flexibly to the particular circumstances of the transmission section. For example, it is known that laser links crossing the atmosphere present difficulties of irregular disturbances in the light intensity (flickering, deflection of the beam) having a typical duration constant of a few milliseconds. When the signaling time interval is chosen in this order of magnitude, the influence of the atmosphere can be suppressed, for example by averaging. This is particularly useful for laser communication links with ground stations or aircraft, both between them and from them with satellites.
    Other embodiments and advantages of the present invention appear from the following description of the figures. In different figures, identical or similar elements are provided with identical or similar references.
    Brief Description of the Drawings The representations in the figures are schematic and are not to scale.
    In the drawing:
    [Fig.l] illustrates a schematic representation of a communication system;
    [Fig.2] illustrates a schematic representation of a communication platform;
    [Fig.3] illustrates a schematic representation for the adjustment of a direction of radiation;
    [Fig.4] illustrates a schematic representation of the intensity of an optical communication signal in different deflection positions;
    [Fig.5] illustrates a schematic representation of a process.
    Description of embodiments [0066] The figure. 1 illustrates a communication system (10) with a first communication platform (100) and a second communication platform (200). The first communication platform (100) can be called transmitter and the second communication platform (200) receiver or remote station.
    A one-way optical transmission section is produced between the first communication platform (100) and the second communication platform (200). This transmission section consists of a data link (20) which can be called optical communication signal or useful signal. The data link (20) is a data link oriented from the first communication platform (100) to the second communication platform (200). Furthermore, a conductive beam (30) is sent from the second communication platform (200) to allow the first communication platform (100) to detect the position of the second communication platform.
    The first communication platform (100) can be a satellite placed in orbit. The second communication platform (200) can also be an orbiting satellite but also an aircraft in the Earth's atmosphere or a distant mobile or stationary station on the surface of the Earth.
    It is expected that the first communication platform (100) begins with a sequence of systematic variations in the emission angle relative to the direction of reception after a period depending on the properties of the system (several minutes). These variations in the emission angle provide for the beam deflection unit to be brought into the deflection positions described above. These variations are for example perpendicular to each other and the direction in the transmitter's coordinate system (of the first communication platform (100) is coded as a function of the duration of the difference (the period during which the beam deflection unit is in a determined deflection position).
    The receiver (the second communication platform (200) on the other side detects the duration and the height of the intensity difference and signals in the opposite direction (for example also by changing the bypass angle or by variation of the power output from the conductive beam (30), the direction causing an increase in the reception intensity. the procedure is repeated multiple times.
    It is conceivable that between the first communication platform (100) and the second communication platform (200), there are two unidirectional data links, the transmitting units and the receiving units of a platform communication channels being functionally separated from each other, so that each of these two unidirectional data links consists of only one forward channel and that an associated return channel is not provided. In such a scenario, the steps of adjusting the beam deflection units of the two communication platforms can be carried out one after the other.
    Figure 2 illustrates a schematic representation of a communication platform (100). The combination platform (100) includes a transmitter (110) producing an optical signal (20) from a data signal (not shown). The optical signal (20) is transmitted and meets a surface of the beam deflection unit (140). The optical signal (20) is reflected by the surface of the beam deflection unit (140), passes a beam splitter (160) before leaving the communication platform (100) via the optical transmit / receive system (105).
    The optical transmission / reception system (105) transmits the communication signal (20). In the opposite direction, the optical transmit / receive system (105) receives the conductive beam (30). The conductive beam (30) is diverted to an intensity detector (150) by the beam splitter (160).
    The beam deflection unit (140) can pivot around a point of rotation (142). The point of rotation (142) in particular allows the beam deflection unit to pivot by two degrees of freedom, therefore such that the optical communication signal can be moved along two different lines of movement (up / down and left / right or horizontally and vertically).
    An actuator (130), for example with one or more electric motors, is provided for moving the beam deflection unit (140). The actuator (130) is controlled by the control unit (120). The control unit (120) defines in which direction and at what angle the beam deflection unit (140) is to be moved. In addition, the control unit (120) is coupled to the intensity detector (150) and is designed to obtain information on the intensity of the conductive beam (30). This information can be interrogated by the control unit (120) or be emitted by the intensity detector (150). The control unit (120) can further determine the duration of the intensity variations.
    It is conceivable that the optical path (the signal path (20 and 30) be modified and to implement the described approach despite everything. It is thus possible, for example, for two beam deflection units to be arranged in the optical path. In addition to the illustrated beam deflection unit (140), a second beam deflection unit may be disposed between the transmit / receive optical system (105) and the beam splitter (160). beam deflection unit can in principle perform the same function as the beam deflection unit (140), however one of these two beam deflection units can be realized to compensate for micro vibrations of the communication platform (100 ) or other relatively rapid deviations of the optical signal, while the other beam deflection unit is then made to adopt a static diversion angle. static rivation can be maintained over a longer period of a few minutes to a few hours to take into account current transmission properties.
    The second beam deflection unit may also include an actuator that can adjust or predict the orientation of the second beam deflection unit.
    The control unit (120) can control the two beam deflection units. In this case, it is possible to use, for the two beam deflection units or only for one of the two, the mechanism described with reference to FIGS. 3 to 5 to calculate an optimal adjustment angle for the optical signal emitted.
    Figure 3 schematically illustrates how an alignment of the optical communication signal of the first communication platform is moved relative to a second communication platform (200) to obtain optimal alignment.
    Only reception sensitivity is illustrated in the form of a dotted circle for the second communication platform (200). A current target point (22) of the optical communication signal is also illustrated. This representation must be understood so that the intensity of the received optical signal is as strong as possible when the target point (22) is in the center in the reception sensitivity, therefore when the optical signal is oriented in such a way receiving device that the receiving device is located in the region of highest intensity of the optical signal. The current target point is certainly oriented towards the second communication platform but can easily be offset from the central point of the optical system of transmission and reception (105). This side shift can cause the signal quality (signal height) at the receiver to be lower than the maximum possible. Adapting the alignment of the optical communication signal improves signal quality. The communications signal should be aligned with the center point of the transmit and receive optical system (105). Generally, the communication signal is aligned to achieve the highest possible signal quality.
    In the representation of Figure 3, two lines of movement (144, 146) are illustrated, one of which is called horizontal line of movement or first line of movement (144) and the other is called line of vertical movement or second line of motion (146). Starting from the starting position (22) (current alignment of the beam deflection unit), the beam deflection unit is moved according to a predefined sequence and according to a predefined deflection angle, at the top left, at the bottom right. If one of these deflection movements induces an improvement in the signal quality at the level of the receiver, the beam deflection unit is moved in the corresponding direction and takes a new position from which the deflection movements are again carried out .
    The possible movements of the beam deflection unit are represented in the form of two arrows to the right and downwards near the point of intersection of the lines of movement (144, 146). These two movements allow the optical communication signal to approach the central point (106).
    A positive and negative direction of movement is displayed respectively at the two lines of movement.
    Figure 4 illustrates two diagrams. The upper diagram illustrates the value of the deflection angle as a function of time, the direction of the deflection angle serving as a reference. The beam deflection unit is first moved in the positive direction along the line of movement (144) (therefore to the right in Figure 3 and remains in this deflection position for the period (tl). the beam deflection unit is then brought back to the starting position and then during the period (t2) in the second deflection position along the line of motion (144) in the negative direction (in Figure 3 to the left Similarly, the movement is carried out along the line of movement 146: first during the period (t3) in the positive direction (in Figure 3 upwards) then during the period (t4) in the negative direction (in Figure 3 down).
    The lower diagram in Figure 4 illustrates the variation in signal strength at the receiver. During the period (tl), the intensity drops. This means that the corresponding deflection position leads to a worsening of the signal quality. During periods (t2 and t3), there are improvements in signal quality, the best signal quality being obtained during period (t3). The period (t4) in turn has a lower signal quality. This means that the beam deflection unit is moved to the position it was in during period (t3). The adjustment is then repeated.
    It is also conceivable that the beam deflection unit is moved continuously in a circle and that the remote station responds with a variation in the intensity of the conductive beam (30) when a maximum of the intensity is achieved. This maximum is typically recognized by the fact that the intensity increases first before decreasing again. If the communication platform (100) receives a variation in intensity of the conducting beam, it can be deduced therefrom that the maximum has been reached before a determined period and that the beam deflection unit can be moved back by a certain value d 'angle. The beam deflection unit (140) can for example traverse a circle with a diameter of 2 prad. This circle can be traversed slowly insofar as the slowing down in time of the conducting beam and in the time necessary for determining the maximum intensity as such is negligible. The travel time of the conductor beam can be deduced from the known distance between the communication platform and the remote station.
    FIG. 5 illustrates the steps of a method (500) for adjusting a direction of radiation of an optical communication signal between a communication platform and a remote station. The method includes the following steps: bringing a beam deflection unit to a starting position in step 510; from the starting position of the beam deflection unit of the communication platform to control the optical communication signal, adoption of deflection positions of the beam deflection unit along two different lines of motion and in opposite directions along the lines of motion in step (520), the deflection positions corresponding in value to the deflection angles and each deflection position being maintained for a different period; measuring an intensity of the optical communication signal at the remote station in step 530; as soon as a variation in the intensity of the optical communication signal is detected at the remote station, determining a variation in signal quality of the optical communication signal and detecting the duration of this variation in intensity at step 540; determining the intensity variation corresponding to the best variation in signal quality as well as the duration associated with step 550; variation of the intensity of a conducting beam for the duration defined in the step preceding to step (560).
    The variation in signal quality considered to be the best is the change leading to the greatest improvement in value of the signal quality. The signal quality can in this case be defined according to known suitable methods.
    The method is preferably carried out with a communication system and a communication platform as well as with a remote station, as described in Figures 1 to 4.
    In addition, it should be noted that "comprising" or "comprising" does not exclude any other element or step and that "one" or "one" does not exclude any plurality. It will also be noted that the characteristics or steps described with reference to one of the previous exemplary embodiments or of the previous configurations can also be used in combination with other characteristics or stages of other exemplary embodiments or configurations previously described. The references in the claims are not limiting.
    NOMENCLATURE OF THE MAIN ELEMENTS [1092] 10 Communication system [0093] 20 Data link, communication signal [0094] 22 Target point of the optical data link [0095] 30 Conductor beam [0096] 100 First platform communication 105 Optical transmission / reception system [0098] 106 Central point of the optical transmission / reception system [0099] 110 Transmitter [0100] 120 Control unit [0101] 130 Actuator [0102] 140 Deviation unit of beam [0103] 142 Point of rotation [0104] 144 First line of movement (with two directions) [0105] 146 Second line of movement (with two directions) [0106] 150 Intensity detector [0107] 160 Beam splitter [0108] 200 Second communication platform [0109] 410 Value of the deflection angle [0110] 420 Variation in intensity of the data link received [YES] 500 Method [0112] 510-560 Process steps
    权利要求:
    Claims (1)
    [1" id="c-fr-0001]
    Communication platform (100), comprising:
    a transmitter (110) for producing an optical communication signal (20);
    an intensity detector (150) for detecting the intensity of a conductive beam (30);
    a beam deflection unit (140) for directing the optical communication signal (20) to a remote station (200); an actuator (130) for rotating the beam deflection unit (140) around a point of rotation (142);
    a control unit (120) for controlling the actuator (130); the control unit being made for:
    controlling the actuator so that the optical communication signal is deflected by the beam deflection unit in a first direction along a first line of motion (144) for a first predefined period (tl) and then it is deflected along the first line of movement (144) in a second direction opposite to the first direction of the first line of movement during a second predefined period (t2); controlling the actuator so that the optical communication signal is then deflected by the beam deflection unit in a first direction along a second motion line (146) for a third predefined period (t3) and qu 'it is then deflected in a second direction opposite to the first direction of the second line of movement for a fourth predefined period (t4) along the second line of movement (146); obtaining a conductive beam intensity detected by the intensity detector (150) and determining a deflection direction of the beam deflection unit along the first line of motion (144) or the second line of motion (146 ) based on the detected intensity and shift the beam deflection unit to a deflection position.
    Communication platform (100) according to claim 1, the control unit (120) being arranged to control the beam deflection unit (140) so that the optical communication signal is deflected by the same value of deflection angle along the first line of movement (144) or the second line [Claim 3] [Claim 4] [Claim 5] [Claim 6] [Claim 7] [Claim 8] of movement (146) each deflection process. Communication platform (100) according to claim 1 or 2, the first line of movement (144) and the second line of movement (146) extending linearly and crossing each other at an angle of 90 °.
    Communication platform (100) according to any one of the preceding claims, each individual period among the second period (t2), the third period (t3) and the fourth period (t4) being an integer multiple of the first period (tl) and distinguishing themselves from each other respectively.
    Communication platform (100) according to any one of the preceding claims, the control unit being designed to control the actuator so that the beam deflection unit is deflected according to a predefined sequence along the first line of movement in the first and second direction and along the second line of movement along the first and second direction.
    Communication platform (100) according to any one of the preceding claims, the control unit being arranged to control the actuator so that the beam deflection unit is brought into a starting position after each deflection process before taking the next deflection position.
    Communication platform (100) according to any one of the preceding claims, the communication platform (100) being a satellite.
    Communication system (10), comprising:
    a communication platform (100) according to any one of the preceding claims;
    a remote station (200);
    the remote station (200) being designed to emit the conductive beam (30) in the direction of the communication platform (100); the remote station (200) being designed to detect the differences in intensity of the optical communication signal as well as the duration of these differences in intensity;
    the remote station (200) being made to determine the difference in intensity of the optical signal having the best signal quality [Claim 9] [Claim 10] [Claim 11] as well as the duration of this difference in intensity;
    the remote station (200) being made to vary an intensity of the conductive beam (30) for the duration of the difference in intensity of the optical communication signal;
    the communication platform being produced to determine, on the basis of the duration of the intensity difference of the conductive beam, the deflection direction of the optical communication signal which corresponds to the duration of the intensity difference of the conductive beam . Communication system (10) according to claim 8, the communication platform (100) being designed to deflect the beam deflection unit after reception of the intensity difference of the conductive beam and to shift it to a target position.
    Communication system (10) according to claim 9, the communication platform (100) being arranged to move the beam deflection unit along the first line of movement (144) in the first direction and then along the first line of movement in the second direction as well as along the second line of movement (146) in the first direction and then along the second line of movement in the second direction after shifting the beam deflection unit in the target position, thereby determining a suitable target position. Method for adjusting a direction of radiation of an optical communication signal (20) between a communication platform (100) and a remote station (200), the method having the following steps: from a starting position a beam deflection unit (140) of the communication platform for directing the optical communication signal, adopting deflection positions of the beam deflection unit (140) along two different lines of motion and in opposite directions along the lines of motion, the deflection positions corresponding to deflection angles equal in value and each deflection position being maintained for a different period;
    measuring an intensity of the optical communication signal at the remote station (200);
    as soon as a variation in the intensity of the optical communication signal is detected at the remote station (200), determining a variation in signal quality of the optical communication signal and detecting the duration of this variation in intensity ;
    [Claim 12] [Claim 13] [Claim 14] determination of the intensity variation which corresponds to the best variation in signal quality as well as the associated duration;
    variation of the intensity of a conducting beam for the duration determined in the previous step.
    The method of claim 11, further comprising the step of: detecting, by the communication platform, the duration of the variation in intensity of the conductive beam; and moving the beam deflection unit to the deflection position which has been adopted for the duration of the variation in intensity of the conductive beam.
    The method of claim 12, the method steps being repeated until the deflection position of the beam deflection unit which corresponds to the best signal quality has been determined along a first line of motion. .
    Method according to claim 12 or 13, the method steps being repeated until the deflection position of the beam deflection unit which corresponds to the best signal quality has been determined in a second line of motion .
    类似技术:
    公开号 | 公开日 | 专利标题
    FR3076967A1|2019-07-19|Beam alignment in unidirectional optical communication systems
    FR2539525A1|1984-07-20|METHOD FOR CORRECTING THE INTENSITY OF A BEAM DURING THE ANALYSIS AND RECORDING OF A FIGURE
    FR2664065A1|1992-01-03|OPTICAL FIBER DETECTOR FOR VARIABLE FIELD DEPTH VIEWING APPARATUS.
    EP0716317A1|1996-06-12|Device for the detection and location of ground objects
    EP2804011B1|2016-08-31|Laser illumination device with built-in shutter
    EP2173042A1|2010-04-07|Optical transmission-reception unit with controllable transmission direction
    EP3488540B1|2020-02-26|Combined imaging and laser communication system
    EP0637147B1|2000-05-10|Tunable optical filter tuning device in particular for use at reception in an optical transmission system
    FR2655497A1|1991-06-07|SYSTEM FOR TRANSMITTING MESSAGES.
    EP2766694B1|2015-12-16|Measuring apparatus for checking the approach path indicator for the landing of an airplane, and corresponding checking device
    WO2020128386A1|2020-06-25|Communication system comprising a matrix image communication receiver
    FR3073839B1|2019-11-15|SYSTEM FOR ALIGNING A THERMAL TREATMENT DEVICE AND ITS OPERATION
    EP3685528B1|2020-11-04|Stealth transmission between a source on board a satellite or an aircraft and a remote receiver
    EP0282399B1|1991-12-27|Base station receiving system for optically transmitted data issued from n mobile stations
    FR3069380B1|2019-10-04|LENS FOR ANTENNA SYSTEM
    EP3289384B1|2020-08-05|Optical system and method for pointing a laser through the atmosphere
    EP3560114A1|2019-10-30|Optical transmission from a satellite to a reception terminal
    EP2990814A1|2016-03-02|Method and device for measuring intermodulation products by reflection of electromagnetic waves on an object
    EP1848962B1|2010-05-26|Device for acquiring a digital image by passive stabilization scanning
    FR3073279A1|2019-05-10|SYSTEM FOR MEASURING A DIAMETER AND / OR THICKNESS OF A TARGET DISPOSED IN A DEPOSIT CHAMBER OF A DEPOSITION EQUIPMENT
    FR3081229A1|2019-11-22|DETECTION OF SIGNAL RE-GENERATION CORRELATION
    FR3040848A1|2017-03-10|METHOD AND SYSTEM FOR BISTATIC IMAGING
    FR3071322A1|2019-03-22|TARGET TRACKING DEVICE COMPRISING A QUADRANT PHOTODETECTOR
    FR3075521A1|2019-06-21|COMMUNICATION SYSTEM COMPRISING A ARTIFICIAL ETOILE COMPENSATION DEVICE
    WO2016008952A1|2016-01-21|Automatic trajectory-mapping system for optical microscope, based on a smart high-speed camera
    同族专利:
    公开号 | 公开日
    US20190163030A1|2019-05-30|
    US10606146B2|2020-03-31|
    DE102017127813A1|2019-05-29|
    引用文献:
    公开号 | 申请日 | 公开日 | 申请人 | 专利标题
    EP0287032A2|1987-04-13|1988-10-19|Nec Corporation|Optical alignment system|
    EP0317373A2|1987-11-20|1989-05-24|British Aerospace Public Limited Company|Laser beam communication between spacecraft|
    EP2680024A2|2012-06-28|2014-01-01|Tesat-Spacecom GmbH & Co. KG|System and method for determining the position of a communication platform|
    DE102012012898A1|2012-06-28|2014-01-02|Tesat-Spacecom Gmbh & Co.Kg|System and method for determining the position of a communication platform|
    WO2014137823A1|2013-03-02|2014-09-12|Aoptix Technologies, Inc.|Rapid in-the-field auto-alignment for radio frequency and free-space optical data communication transceivers|
    EP3100378A1|2014-01-28|2016-12-07|Sa Photonics, Inc.|Free space optical communication tracking with electronic boresight compensation and co-boresighted transmit and receive optics|
    EP0863627B1|1997-03-07|2001-09-19|Contraves Space AG|Method and means for optical data transmission via satellites|
    DE60100824T2|2000-05-10|2004-07-01|Lucent Technologies Inc.|Method and device for transmission signal tracking in an optical free space transmission system|
    US7215890B2|2003-09-29|2007-05-08|Harris Corporation|Free space optical device providing power reduction features and related methods|
    US7221874B2|2003-09-29|2007-05-22|Harris Corporation|Free space optical device providing remote control features and related methods|
    DE102007024075A1|2007-05-22|2008-11-27|Leica Microsystems Cms Gmbh|Tunable acousto-optic filter element|
    US8301032B2|2008-02-12|2012-10-30|Arun Kumar Majumdar|Wide field-of-view amplified fiber-retro for secure high data rate communications and remote data transfer|
    JP5985661B2|2012-02-15|2016-09-06|アップル インコーポレイテッド|Scan depth engine|
    US9482862B2|2013-07-26|2016-11-01|Neophotonics Corporation|Adjustable grid tracking transmitters and receivers|
    US9395293B1|2015-01-12|2016-07-19|Verily Life Sciences Llc|High-throughput hyperspectral imaging with superior resolution and optical sectioning|
    US9991957B2|2015-11-16|2018-06-05|Arizona Board Of Regents On Behalf Of Arizona State University|Low-cost, long-distance, high-bandwidth laser communication system for small mobile devices and spacecraft|
    BR112019012069A2|2016-12-16|2019-11-12|Quantum-Si Incorporated|compact beam targeting and modeling set|
    US10003168B1|2017-10-18|2018-06-19|Luminar Technologies, Inc.|Fiber laser with free-space components|RU2717559C2|2016-03-22|2020-03-24|ЛАЙТЛУП ТЕКНОЛОДЖИЗ, ЭлЭлСи|System and method of storing data in motion|
    AU2019377800A1|2018-11-05|2021-03-18|Lyteloop Technologies, Llc|Systems and methods for building, operating and controlling multiple amplifiers, regenerators and transceivers using shared common components|
    DE102021101423B3|2021-01-22|2022-03-03|Tesat-Spacecom Gmbh & Co. Kg|Pivoting mechanism for communication units|
    法律状态:
    2019-11-20| PLFP| Fee payment|Year of fee payment: 2 |
    2020-05-29| PLSC| Publication of the preliminary search report|Effective date: 20200529 |
    2020-11-20| PLFP| Fee payment|Year of fee payment: 3 |
    2021-11-22| PLFP| Fee payment|Year of fee payment: 4 |
    优先权:
    申请号 | 申请日 | 专利标题
    DE102017127813.3|2017-11-24|
    DE102017127813.3A|DE102017127813A1|2017-11-24|2017-11-24|Beam alignment in unidirectional optical communication systems|
    [返回顶部]