CN111416661A - Light path alignment method for space optical communication - Google Patents
Light path alignment method for space optical communication Download PDFInfo
- Publication number
- CN111416661A CN111416661A CN202010042513.4A CN202010042513A CN111416661A CN 111416661 A CN111416661 A CN 111416661A CN 202010042513 A CN202010042513 A CN 202010042513A CN 111416661 A CN111416661 A CN 111416661A
- Authority
- CN
- China
- Prior art keywords
- scanning
- optical
- power value
- optical communication
- transverse
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 230000003287 optical effect Effects 0.000 title claims abstract description 191
- 238000000034 method Methods 0.000 title claims abstract description 85
- 238000004891 communication Methods 0.000 title claims abstract description 75
- 239000000523 sample Substances 0.000 claims abstract description 24
- 230000008569 process Effects 0.000 claims abstract description 22
- 230000033001 locomotion Effects 0.000 claims description 15
- 238000003384 imaging method Methods 0.000 abstract description 2
- 230000009286 beneficial effect Effects 0.000 description 9
- 238000010586 diagram Methods 0.000 description 5
- 230000007423 decrease Effects 0.000 description 3
- 238000005259 measurement Methods 0.000 description 3
- 239000013307 optical fiber Substances 0.000 description 3
- 238000010276 construction Methods 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 230000003321 amplification Effects 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 238000003199 nucleic acid amplification method Methods 0.000 description 1
- 230000004044 response Effects 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
- 238000004904 shortening Methods 0.000 description 1
Images
Classifications
-
- 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
- H04B10/07—Arrangements for monitoring or testing transmission systems; Arrangements for fault measurement of transmission systems
- H04B10/075—Arrangements for monitoring or testing transmission systems; Arrangements for fault measurement of transmission systems using an in-service signal
- H04B10/079—Arrangements for monitoring or testing transmission systems; Arrangements for fault measurement of transmission systems using an in-service signal using measurements of the data signal
- H04B10/0795—Performance monitoring; Measurement of transmission parameters
- H04B10/07955—Monitoring or measuring power
Abstract
The invention belongs to the field of wireless communication, and particularly relates to a light path alignment method for space optical communication, which comprises the following steps: adjusting the positions of a light spot of a collimation light path to be aligned and a two-dimensional area to be scanned at the probe end of the detector respectively, so that the light spot is projected in the two-dimensional area to be scanned; and controlling the probe to scan the two-dimensional area, synchronously detecting the optical power value of the current scanning point in real time in the scanning process, comparing the optical power value with the optical communication power threshold, stopping scanning when the optical power value or a plurality of continuous adjacent optical power values including the optical power value is greater than the optical communication power threshold, and realizing light path alignment, otherwise, continuing scanning until reaching a scanning termination condition. The invention obtains the light power value of each discrete scanning point in the scanning process in real time through a scanning mode, realizes light path alignment based on the power threshold, is suitable for light paths of different types of light sources, and avoids the problems of complex alignment system, high cost, time-consuming alignment and the like caused by CCD imaging and the like required by the existing light path alignment method.
Description
Technical Field
The invention belongs to the field of wireless communication, and particularly relates to an optical path alignment method for space optical communication.
Background
Since the 21 st century, information technology and the internet have been rapidly developed, and people demand networks with larger bandwidths and faster rates. Currently, optical fiber communication is a main transmission mode of a core network, but the application of optical fiber communication is limited in some scenes, such as situations of crossing rivers and seas or urban cells where optical fibers are inconvenient to lay. Therefore, free space optical communication is a novel point-to-point communication mode developed in recent ten years, has the advantages of flexible system construction, high safety and the like, is a high-quality scheme for solving the last kilometer of communication, and is widely applied in the scenes of military affairs, satellite-ground communication, temporary communication system construction and the like at present. The most important premise of free space optical communication is the capture alignment of the optical path, and the alignment of the optical path is difficult to realize due to the factors such as long communication distance and atmospheric turbulence.
At present, the main method for realizing the light path capturing alignment in the satellite-ground free space optical communication system is to acquire satellite orbit data, image by using an optical lens group and a CCD (charge coupled device), and then calibrate. The main method for realizing the light path capturing alignment of the civil free space optical communication system is to use a telescope to carry out coarse alignment and then manually adjust, so that the efficiency is low, the realization difficulty is high, and the stability is low.
Disclosure of Invention
The invention provides an optical path alignment method for space optical communication, which is used for solving the technical problem of low alignment efficiency in the existing optical path alignment method for space optical communication because the long-distance alignment needs to be realized by means of a CCD imaging technology and the short-distance alignment needs to be manually adjusted.
The technical scheme for solving the technical problems is as follows: an optical path alignment method for spatial optical communication, comprising:
adjusting the positions of a light spot of a collimation light path to be aligned and a two-dimensional area to be scanned at the probe end of a detector respectively, so that the light spot is projected in the two-dimensional area to be scanned;
and controlling the probe to scan the two-dimensional area, synchronously detecting the optical power value of the current scanning point in real time in the scanning process, comparing the optical power value with an optical communication power threshold, stopping scanning when the optical power value or a plurality of continuous adjacent optical power values including the optical power value is greater than the optical communication power threshold, and realizing light path alignment, otherwise, continuing scanning until reaching a scanning termination condition.
The invention has the beneficial effects that: the method obtains the optical power value of each discrete scanning point in the scanning process in real time through a scanning mode, judges whether the optical power value of the current position reaches the power threshold value based on the preset optical communication power threshold value, and can carry out optical path alignment based on the current position if the optical power value of the current position reaches the power threshold value.
On the basis of the technical scheme, the invention can be further improved as follows.
Further, the optical communication power threshold is-20 dBm + PnWherein P isnIs a predetermined error value.
The invention has the further beneficial effects that: in order to eliminate optical path jitter interference or meet actual measurement requirements.
Further, a stepper motor is employed to control the movement of the probe to scan the two-dimensional region.
The invention has the further beneficial effects that: the response steps of the stepping motor only depend on the number of digital pulses of the control signal, so the control is easy, the motion error of each step can not be accumulated, and the motion precision is high, therefore, the adoption of the stepping motor can simply, flexibly and accurately control the position of each scanning point of the probe.
Further, the scanning method for scanning the two-dimensional region by the probe comprises the following steps:
and performing transverse and longitudinal alternate repeated scanning on the two-dimensional area, wherein the path of the first transverse scanning is positioned outside the light spot area, the directions of every two adjacent transverse scanning are opposite, and the directions of every two longitudinal scanning are the same.
The invention has the further beneficial effects that: and the scanning is carried out on a two-dimensional area in a horizontal-vertical alternative mode, so that the control is convenient, and the problems that the scanning point cannot be controlled and the optical power value can not be acquired due to spiral scanning are solved.
Further, in the scanning method, the start and stop points of each transverse scanning are on the outline of the two-dimensional area.
The invention has the further beneficial effects that: the full-coverage scanning of the two-dimensional area is ensured, and the efficiency and the precision of light path alignment are improved.
Further, the plurality of optical power values which are continuously adjacent are 3-5 optical power values which are continuously adjacent in the current transverse scanning.
The invention has the further beneficial effects that: if the optical power values corresponding to 3-5 continuous adjacent scanning points are larger than the optical communication power threshold, the light path light spot position can be found, and the reliability is high.
Further, when the light field distribution of the light spots of the collimation light path to be aligned is Gaussian, in the scanning method, the maximum power value of the transverse scanning is obtained through statistics at the end of each transverse scanning;
wherein the start and stop points of the first transverse scanning are on the outline of the two-dimensional area; before each transverse scanning, judging whether the maximum power value of the last transverse scanning is smaller than a rapid scanning power threshold value, if so, keeping the start point and the end point of the transverse scanning on the outline of the two-dimensional area; if not, in the process of the transverse scanning, when the optical power value is in a descending trend and the power value of the current scanning point is equal to the maximum power value of the previous line, stopping the transverse scanning and entering the longitudinal scanning to enter the next transverse scanning, wherein the fast scanning power threshold is smaller than the optical communication power threshold.
The invention has the further beneficial effects that: the method sets two power thresholds, namely a rapid scanning power threshold and an optical communication power threshold, shortens a two-dimensional scanning path after reaching the scanning power threshold, moves to the optical communication power threshold more quickly, achieves optical path alignment more quickly, and is suitable for laser sources with Gaussian light intensity distribution.
Further, the method for determining the plurality of consecutive adjacent optical power values specifically includes:
and when the optical power value appearing for the first time is larger than the optical communication power threshold, continuing the current transverse scanning, determining the position corresponding to the maximum optical power value in the current transverse scanning process based on the optical power value variation trend in the current transverse scanning, and determining a plurality of continuous adjacent optical power values corresponding to the maximum optical power value after the optical power value appearing for the first time and larger than the optical communication power threshold is sequentially scanned as the plurality of continuous adjacent optical power values.
The invention has the further beneficial effects that: during the whole movement process, the current power value is always monitored, and if the power value is larger than the threshold value P during the period0In this case, the lateral motion does not stop immediately, but continues to search for the power maximum point, and then stops scanning and performs optical path alignment to provide alignment accuracy.
Further, the path length of each longitudinal scan is the same as the probe tip face size.
The invention has the further beneficial effects that: the mode limits the distance between every two times of transverse scanning, ensures that no scanning blank space exists between every two adjacent times of transverse scanning, realizes the comprehensive scanning of a two-dimensional region without dead angles, and further improves the scanning efficiency and precision.
The present invention also provides a storage medium having instructions stored therein, which when read by a computer, cause the computer to execute any one of the above-described optical path alignment methods for spatial optical communication.
Drawings
Fig. 1 is a block flow diagram of an optical path alignment method for spatial optical communication according to an embodiment of the present invention;
FIG. 2 is a schematic diagram of an optical path alignment system based on a two-dimensional electric platform according to an embodiment of the present invention;
fig. 3 is a schematic view of a scanning track under the whole scanning of a two-dimensional area to be scanned according to an embodiment of the present invention;
FIG. 4 is a schematic scanning diagram of the start and stop points of each transverse scanning on the outline of the two-dimensional region according to the embodiment of the present invention;
FIG. 5 is a graph illustrating a variation of the power data corresponding to FIG. 4;
fig. 6 is a schematic scanning diagram of a gaussian light field distribution suitable for a light spot of a collimation light path to be aligned according to an embodiment of the present invention;
fig. 7 is a graph illustrating a variation of power data corresponding to fig. 6.
The same reference numbers will be used throughout the drawings to refer to the same or like elements or structures, wherein:
1. laser emitting device, 2, lens collimation way expanding device, 3, detecting device, 4, first lens, 5, second lens.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention. In addition, the technical features involved in the embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.
Example one
An optical path alignment method 100 for spatial optical communication, as shown in fig. 1, includes:
step 110, adjusting the positions of a light spot of a collimation light path to be aligned and a two-dimensional area to be scanned at the probe end of a detector respectively, so that the light spot is projected in the two-dimensional area to be scanned;
It should be noted that the optical power value of each current scanning point is read by a power detection circuit, and the scanning motion of the probe is controlled by a core controller through a scanning algorithm. Specifically, as shown in fig. 2, a schematic diagram of an overall optical path structure of a system corresponding to a two-dimensional electric platform-based optical path fast alignment method mainly includes a laser emitting device 1, a lens alignment path expanding device 2, and a detecting device 3. The wavelength of the laser is 1550nm, and the power is 4 mW. The collimation and beam expansion part mainly comprises two focal lengths of f1And f2The first lens 4 and the second lens 5 can collimate the light path to a required size by adjusting the distance, the light path is expanded to a diameter of 10mm in the example, a PIN tube with the diameter of 3mm × 3mm is adopted as a photoelectric detector, current and voltage conversion and amplification are carried out on the photoelectric detector, a 12-bit ADC is used for converting an analog voltage signal into a digital signal, the corresponding measurement precision is 0.1dBm, and the digital signal is read by using an FPGA.
The method obtains the optical power value of each discrete scanning point in the scanning process in real time through a scanning mode, judges whether the optical power value of the current position reaches the power threshold value based on the preset optical communication power threshold value, and can carry out optical path alignment based on the current position if the optical power value of the current position reaches the power threshold value.
Preferably, the optical communication power threshold is-20 dBm + PnWherein P isnIs a predetermined error value.
The optical communication power threshold is typically-20dBm, and an error value P can be set for eliminating the optical path jitter interference or meeting the actual measurement requirementn，PnIs greater than or equal to 0.
Preferably, a stepper motor is used to control the movement of the probe to scan a two-dimensional area.
The adoption of the stepping motor can simply, flexibly and accurately control the position of each scanning point of the probe.
Preferably, the plurality of optical power values that are continuously adjacent to each other are 3 to 5 optical power values that are continuously adjacent to each other. If the optical power values corresponding to 3-5 continuous adjacent scanning points are larger than the optical communication power threshold, the light path light spot position can be found, and the reliability is high.
Preferably, the method for scanning the two-dimensional region by the probe includes:
and performing transverse and longitudinal alternate repeated scanning on the two-dimensional area, wherein the path of the first transverse scanning is positioned outside the spot area, the directions of every two adjacent transverse scanning are opposite, and the direction of every longitudinal scanning is the same.
And the scanning is carried out on a two-dimensional area in a horizontal-vertical alternative mode, so that the control is convenient, and the problems that the scanning point cannot be controlled and the optical power value can not be acquired due to spiral scanning are solved.
Preferably, in the scanning method, the start point and the end point of each horizontal scanning are located on the outline of the two-dimensional region. Therefore, the full-coverage scanning of the two-dimensional area is ensured, and the efficiency and the precision of light path alignment are improved.
Preferably, the path length of each longitudinal scan is the same size as the probe tip face. The mode limits the distance between every two times of transverse scanning, ensures that no scanning blank space exists between every two adjacent times of transverse scanning, realizes the comprehensive scanning of a two-dimensional region without dead angles, and further improves the scanning efficiency and precision.
Before the scanning operation, the optical communication power threshold P needs to be set0And probe scan range. When the scanning is started, the horizontal and vertical motors are reset respectively, and then the horizontal and vertical motors repeatedly scan for a fixed number of times, so that the set target range can be scanned. During this period, the optical power value P is always monitored, if P appearsGreater than optical communication power threshold P0And if so, immediately stopping scanning, displaying that the scanning is successful, and exiting the program.
For example, the two-dimensional region is rectangular, and if the two-dimensional region is completely scanned according to the scanning method, as shown in fig. 3, a software algorithm corresponding to the scanning method may be implemented on the FPGA by using verilog language programming. The determination process of the scanning path comprises the following steps: before the program runs, the motion step number N of the disposable scanning stepping motor is set according to the size of the two-dimensional area1Setting the number of column scans M1Number of moving steps N of one-time column scanning stepping motor2And the step length of the motor movement is s (transverse scanning distance: N)1× s 420 × 0.1.1 mm 42mm, and the longitudinal scanning distance N2× s-30 × 0.1.1 mm-3 mm, and M times of vertical scanning113), the two-dimensional scan range is Q, where: q is N1×N2×(M1+1)×s2. The method comprises the following specific steps: after the horizontal motor and the vertical motor are respectively reset, the horizontal motor directly starts scanning in the first row, stops after moving for a set fixed step number N1 and transmits an enabling signal to the vertical motor, and stops after the vertical motor starts moving for a fixed step number N2 and transmits an enabling signal to the horizontal motor, the direction of the horizontal motor is reversed, and the horizontal motor starts scanning in the second row, so that the target range Q (namely a two-dimensional area) can be scanned by repeatedly scanning the rows and columns for a fixed time number M1.
And if the scanning paths before the optical communication power threshold value is not reached are consistent, the starting point and the ending point of each transverse scanning are on the outline of the rectangular two-dimensional area, the FPGA carries out fixed-stroke two-dimensional scanning according to the size of the optical power value P until the current optical power value reaches the optical communication power threshold value, the scanning is stopped and the display is successful, otherwise, after all transverse scanning is finished, the scanning is suspended, the display is unsuccessful, and the scanning is waited to be started again. Specifically, as shown in fig. 4, a power value greater than-40 dBm appears in the 5 th line scan, but the program does not use-40 dBm as the optical communication power threshold and does not stop the scan. Similarly, the scanning of the 6 th and 7 th lines is normally carried out until the power value reaches the threshold value of-20 dBm in the 8 th line, at the moment, the motor immediately stops scanning, the scanning success is displayed, and the program is exited. In the scanning process, when the optical power value is lower than-20 dBm, the motor does not stop moving, and when the optical power value reaches the point B of-20 dBm, the motor stops moving immediately, which indicates that a target point is found, and the optical path alignment is carried out. In addition, as shown in FIG. 5, the magnitude of the optical power value varies with the scanning time, and it can be seen that the only judgment condition for the scanning operation is the power threshold of-20 dBm, and when the power value reaches-20 dBm, the scanning is stopped.
Judging that the optical power value is greater than P0The conditions of (a) are: power value P in 3 consecutive clock cyclestAre all greater than P0+PnI.e. Pt＞P0+PnT ═ i-2, i-1, i, where PnThereby eliminating the optical path jitter interference.
The scanning method of the start point and the stop point of each transverse scanning on the two-dimensional area profile is suitable for the rapid capture alignment of various light source light paths of different types, and has the advantages of wide application range, simple and efficient alignment process.
When the light field distribution of the light spots of the collimation light path to be aligned is gaussian, preferably, in the scanning method, the maximum power value of the transverse scanning is obtained by statistics at the end of each transverse scanning;
wherein, the starting point and the stopping point of the first transverse scanning are on the outline of the two-dimensional area; before each transverse scanning, judging whether the maximum power value of the last transverse scanning is smaller than a rapid scanning power threshold value, if so, keeping the start point and the end point of the transverse scanning on the outline of the two-dimensional area; if not, in the process of the transverse scanning, when the optical power value is in a descending trend and the power value of the current scanning point is equal to the maximum power value of the previous line, stopping the transverse scanning and entering the longitudinal scanning to enter the next transverse scanning, wherein the rapid scanning power threshold is smaller than the optical communication power threshold.
In particular, it can be described as: the starting point and the ending point of the first transverse scanning are on the outline of the two-dimensional area, then before each transverse scanning, whether the maximum power value of the last transverse scanning is smaller than the rapid scanning power threshold value or not is judged, if yes, in the transverse scanning process, the power value of the current scanning point is synchronously obtained in real time, the current detected optical power value is compared with the optical communication power threshold value, when the current detected optical power value or a plurality of continuous adjacent optical power values is larger than the optical communication power threshold value, the scanning is stopped, the optical path alignment is realized, otherwise, the scanning is continued, the starting point and the ending point of the transverse scanning are still on the outline of the two-dimensional area, and the maximum power value of the transverse scanning is obtained through statistics. If not, in the process of the transverse scanning, acquiring the power value of the current scanning point in real time, synchronously comparing the currently detected optical power value with the optical communication power threshold value and judging the change trend of the optical power value, when the currently detected optical power value or a plurality of continuous adjacent optical power values is larger than the optical communication power threshold value, stopping scanning to realize optical path alignment, or when the optical power value is in a descending trend and the power value of the current scanning point is equal to the maximum power value of the previous line, stopping the transverse scanning and entering the next longitudinal scanning; otherwise, continuing the transverse scanning until the scanning point of the transverse scanning reaches the outline of the two-dimensional area so as to carry out the next longitudinal scanning; wherein the fast scan power threshold is less than the optical communication power threshold.
The scanning mode is suitable for light spots distributed in a Gaussian light field, and the light intensity distribution of the light spots is known, so that the scanning path can be shortened based on the known information, and the scanning efficiency is improved. Wherein, in the process of line scanning movement, P is judged after each step of movementiAnd the current line Pmax(h) If P is the size ofi＞Pmax(h)+PnThen P ismax(h)＝Pi(ii) a Otherwise, Pmax(h) Remain unchanged. In addition, whether the maximum power value of the last horizontal scanning is smaller than the fast scanning power threshold or not is judged, that is, whether the maximum power value of the last horizontal scanning is larger than or equal to the fast scanning power threshold or not is judged, and the judging method is as follows: power value PtP at the 3 rd clock time when the value becomes smaller in continuous 3 clock cyclesiValue is equal to Pmax(h-1), namely:
Pi-3＞Pi-2＞Pi-1＞Pi＝Pmax(h-1)。
specifically, before the scanning operation, the optical communication power also needs to be setRate threshold value P0Intermediate threshold (i.e. fast scan power threshold P)A，PA＜P0) And the motor scans the two-dimensional range. When the operation starts, the horizontal and vertical motors are reset respectively, and then the horizontal and vertical motors repeatedly scan for a fixed number of times, so that the set target range can be scanned. Unlike the scanning method in which the start and end points of each transverse scan are located on the contour of the two-dimensional region, the scanning method records the maximum power value P of the current line during the movement of each linemax(h) And h denotes a scan line code (i.e., the number of horizontal scans).
During the scanning period, before each line starts scanning, the previous line P is judgedmax(h-1) whether or not greater than PAIf the previous row P appearsmax(h-1) greater than PAIn this case, the scan completion condition for the current row h is set such that the current power value decreases to Pmax(h-1), then immediately stopping the motion of the line, and directly carrying out longitudinal scanning, thus repeatedly shortening the transverse scanning path and improving the running speed.
For example, as shown in fig. 6, a power value greater than P occurs in the 5 th line scanA(fast scan power threshold PACan take a point c of-40 dBm) and record the row 5 power maximum: pmax(5)＝Pmax(c)Then the scan end point of the 6 th line is the power value equal to Pmax(c)I.e. when the following conditions exist, the 6 th line scan is terminated: pi-3＞Pi-2＞Pi-1＞Pe＝Pmax(c) In that respect Simultaneously recording the maximum power value P of the 6 th rowmax(6)＝Pmax(d). Similarly, the scanning end point of the 7 th line is the power value equal to Pmax(d)Point g, P ofi-3＞Pi-2＞Pi-1＞Pg＝Pmax(6)＝Pmax(d). Recording the 7 th row power maximum P simultaneouslymax(7)＝Pmax(f)Until line 8, a point h is reached where the power level is greater than-20 dBm.
Preferably, the method for determining the plurality of consecutive adjacent optical power values specifically includes:
and when the optical power value appearing for the first time is larger than the optical communication power threshold, continuing the current transverse scanning, determining the position corresponding to the maximum optical power value in the current transverse scanning process based on the optical power value variation trend in the current transverse scanning, and determining a plurality of continuous adjacent optical power values corresponding to the maximum optical power value after the optical power value appearing for the first time and larger than the optical communication power threshold is sequentially scanned as the plurality of continuous adjacent optical power values.
That is, during the whole motion process, the current power value is always monitored, and if the power value is larger than the threshold value P during the period0In this case, the lateral motion does not stop immediately, but continues to search for the point of maximum power, then stops scanning, and indicates that scanning was successful, and the process exits. The above-mentioned implementation of optical path alignment is specifically to align the maximum optical power value P by adjusting the probemaxCorresponding position.
In particular, for example, in the presence of an optical power value greater than a threshold value P0After the situation, the method for continuously searching the maximum power point comprises the following steps: the motor continues to move until power value PtStarting to decrease for 3 consecutive clock cycles, at which time the motor runs in reverse 3 steps and stops moving, indicating that the power maximum point has been reached, as shown:
Pmax＝Pi＞Pi+1＞Pi+2＞Pi+3。
for example, as shown in fig. 6, a point h with a power value greater than-20 dBm is found on the 8 th row, and then the transverse scanning continues until the power value decreases for 3 consecutive clocks, at which time the motor runs in reverse for 3 steps, and reaches a point B: pB＝Pi＞Pi+1＞Pi+2＞Pi+3And stopping scanning immediately, displaying that the scanning is successful, exiting the program, and searching the maximum power value by the system at the moment, thereby improving the stability and the reliability of the system.
As shown in fig. 7, in the case where the data size of the power value varies with the scanning time, it can be seen that the maximum power value reaches P in the horizontal scanning of a certain lineAAfter the threshold value, the scanning power end point of each line is the maximum power value of the last transverse scanning, and the final power peak value exceeds-20 dBm to reach the maximum power point B.
In addition, the path length of each longitudinal scan is preferably the same as the probe tip face size.
The method sets two power thresholds (a fast scanning power threshold and an optical communication power threshold), shortens a two-dimensional scanning path after the fast scanning power threshold is reached, moves to the optical communication power threshold more quickly, and achieves optical path alignment more quickly. The scanning method is suitable for the light spots with Gaussian light field distribution, and because the light intensity distribution of the light spots is known, the scanning path can be shortened and the scanning efficiency can be improved based on the known information.
In summary, for spatial optical communication, when a laser light source with any optical field distribution is used, because the specific optical field distribution form is unpredictable, a scanning method that starting and stopping points of each transverse scanning are on a two-dimensional area profile is used, and an optical communication power threshold is used as a criterion to scan an optical field, so that optical path alignment can be realized; when the laser light source with Gaussian light field distribution is used, the specific light field distribution form is determined to be the Gaussian distribution with concentrated center, and the scanning method of the shortened path is used, so that the shortened scanning path can be adjusted after the laser light source is scanned to the middle threshold point, the laser light source moves to the center of the light field more quickly, and the light path alignment is realized more quickly. Based on the method, a two-mode optical path rapid alignment scanning method is designed, and the problems of low manual adjustment efficiency, high implementation difficulty and poor stability at present are solved.
Specifically, according to the light intensity distribution characteristics of the light source, on the basis of scanning that a probe performs horizontal and longitudinal alternate repeated scanning on a two-dimensional region, wherein the path of the first horizontal scanning is positioned outside a light spot region, the directions of every two adjacent horizontal scanning are opposite, and the direction of every longitudinal scanning is the same, in the two scanning methods designed in the embodiment, one scanning method is that the starting point and the ending point of every horizontal scanning are on the outline of the two-dimensional region, and is suitable for rapid capture and alignment of various different types of light source light paths, namely under the scene of an unknown light intensity distribution light source or an inhomogeneous light source, rapid and accurate alignment of the light paths can be realized, and the method is not influenced by the light source type and has wide applicability; the other scanning method is to perform shortened path scanning based on the maximum power value of each transverse scanning, the starting point and the stopping point of each transverse scanning line are not necessarily on the outline of a two-dimensional area, the method is suitable for common Gaussian light sources such as a semiconductor laser and the like, faster and more stable light path alignment can be realized, and compared with the former scanning method, the method is faster in speed and more stable in peak power.
In addition, it should be noted that, in the two scanning methods, if the scanning of the two-dimensional area is finished and the target power value point is not yet found, the program is suspended after the scanning is finished, the scanning is not successful, and then a new round of scanning can be performed in a reverse direction through key control, and the scanning range is not changed.
Example two
A storage medium, wherein instructions are stored in the storage medium, and when the instructions are read by a computer, the instructions cause the computer to execute an optical path alignment method for spatial optical communication according to the first embodiment.
The related technical solution is the same as the first embodiment, and is not described herein again.
It will be understood by those skilled in the art that the foregoing is only a preferred embodiment of the present invention, and is not intended to limit the invention, and that any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the scope of the present invention.
Claims (10)
1. An optical path alignment method for spatial optical communication, comprising:
adjusting the positions of a light spot of a collimation light path to be aligned and a two-dimensional area to be scanned at the probe end of a detector respectively, so that the light spot is projected in the two-dimensional area to be scanned;
and controlling the probe to scan the two-dimensional area, synchronously detecting the optical power value of the current scanning point in real time in the scanning process, comparing the optical power value with an optical communication power threshold, stopping scanning when the optical power value or a plurality of continuous adjacent optical power values including the optical power value is greater than the optical communication power threshold, and realizing light path alignment, otherwise, continuing scanning until reaching a scanning termination condition.
2. A method according to claim 1The optical path alignment method for space optical communication is characterized in that the optical communication power threshold is-20 dBm + PnWherein P isnIs a predetermined error value.
3. An optical path alignment method for spatial optical communication according to claim 1, wherein a step motor is used to control the movement of the probe to scan the two-dimensional region.
4. An optical path alignment method for spatial optical communication according to any one of claims 1 to 3, wherein the scanning method for scanning the two-dimensional region by the probe is as follows:
and performing transverse and longitudinal alternate repeated scanning on the two-dimensional area, wherein the path of the first transverse scanning is positioned outside the light spot area, the directions of every two adjacent transverse scanning are opposite, and the directions of every two longitudinal scanning are the same.
5. The optical path alignment method for spatial optical communication according to claim 4, wherein in the scanning method, the start point and the end point of each transverse scan are on the outline of the two-dimensional region.
6. The optical path alignment method for spatial optical communication according to claim 4, wherein the plurality of consecutive adjacent optical power values are, in particular, 3 to 5 consecutive adjacent optical power values in the current horizontal scanning.
7. The optical path alignment method for spatial optical communication according to claim 4, wherein when the optical field distribution of the collimated optical path spot to be aligned is gaussian, in the scanning method, the maximum power value of each horizontal scan is obtained by statistics at the end of the horizontal scan;
wherein the start and stop points of the first transverse scanning are on the outline of the two-dimensional area; before each transverse scanning, judging whether the maximum power value of the last transverse scanning is smaller than a rapid scanning power threshold value, if so, keeping the start point and the end point of the transverse scanning on the outline of the two-dimensional area; if not, in the process of the transverse scanning, when the optical power value is in a descending trend and the power value of the current scanning point is equal to the maximum power value of the previous line, stopping the transverse scanning and entering the longitudinal scanning to enter the next transverse scanning, wherein the fast scanning power threshold is smaller than the optical communication power threshold.
8. The optical path alignment method according to claim 7, wherein the method for determining the consecutive adjacent optical power values specifically comprises:
and when the optical power value appearing for the first time is larger than the optical communication power threshold, continuing the current transverse scanning, determining the position corresponding to the maximum optical power value in the current transverse scanning process based on the optical power value variation trend in the current transverse scanning, and determining a plurality of continuous adjacent optical power values corresponding to the maximum optical power value after the optical power value appearing for the first time and larger than the optical communication power threshold is sequentially scanned as the plurality of continuous adjacent optical power values.
9. The method for optical path alignment of spatial optical communication according to claim 7, wherein the path length of each longitudinal scan is the same as the size of the probe end face.
10. A storage medium having stored therein instructions, which when read by a computer, cause the computer to execute a method of optical path alignment for spatial optical communication according to any one of claims 1 to 9.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010042513.4A CN111416661B (en) | 2020-01-15 | 2020-01-15 | Light path alignment method for space optical communication |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010042513.4A CN111416661B (en) | 2020-01-15 | 2020-01-15 | Light path alignment method for space optical communication |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN111416661A true CN111416661A (en) | 2020-07-14 |
| CN111416661B CN111416661B (en) | 2021-06-29 |
Family
ID=71493971
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010042513.4A Expired - Fee Related CN111416661B (en) | 2020-01-15 | 2020-01-15 | Light path alignment method for space optical communication |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111416661B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114900236A (en) * | 2022-07-15 | 2022-08-12 | 中北大学 | Line-of-sight space optical bidirectional communication system and method based on BOSA |
Citations (18)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101001110A (en) * | 2006-12-31 | 2007-07-18 | 桂林电子科技大学 | Radio laser scanning communication method |
| CN101140422A (en) * | 2007-08-20 | 2008-03-12 | 上海微电子装备有限公司 | Mask alignment making and aligning used for light scribing device |
| CN102571204A (en) * | 2011-12-09 | 2012-07-11 | 西安电子科技大学 | Optical transmitting antenna system and beam control method thereof |
| CN103560832A (en) * | 2013-11-15 | 2014-02-05 | 哈尔滨工业大学 | Feedback type light source aligning control method in white light communication |
| CN103675795A (en) * | 2013-12-20 | 2014-03-26 | 中国科学技术大学 | Device and method for automatically matching laser radar receiving and transmitting optical axes |
| CN103916183A (en) * | 2014-04-16 | 2014-07-09 | 电子科技大学 | Fast acquisition system and method based on laser phased technology |
| CN104320182A (en) * | 2014-09-30 | 2015-01-28 | 中国电子科技集团公司第四十一研究所 | Device and method for calibrating consistency of emission shaft and receiving shaft of space optical communication system |
| CN104618015A (en) * | 2015-01-04 | 2015-05-13 | 西安应用光学研究所 | Small atmosphere laser communication device and method |
| CN105021526A (en) * | 2015-08-04 | 2015-11-04 | 安徽皖仪科技股份有限公司 | Laser gas analyzer with automatic light path alignment function |
| CN105510230A (en) * | 2016-01-15 | 2016-04-20 | 中国人民解放军理工大学 | System and method for automatically collimating measuring light path of transmission instrument based on scanning mode |
| US20170244482A1 (en) * | 2016-02-24 | 2017-08-24 | Qualcomm Incorporated | Light-based communication processing |
| US9853740B1 (en) * | 2017-06-06 | 2017-12-26 | Surefire Llc | Adaptive communications focal plane array |
| CN109450532A (en) * | 2018-12-27 | 2019-03-08 | 中国电子科技集团公司第三十四研究所 | With the wireless light communication tracking system for being directed toward correction and it is directed toward antidote |
| CN109831798A (en) * | 2019-03-26 | 2019-05-31 | 惠州Tcl移动通信有限公司 | Signal acquiring method, system, storage medium and mobile terminal |
| CN110233665A (en) * | 2019-05-28 | 2019-09-13 | 西南电子技术研究所（中国电子科技集团公司第十研究所） | Radio frequency/laser collaboration fast Acquisition tracks alignment methods |
| CN110233664A (en) * | 2019-04-25 | 2019-09-13 | 西安理工大学 | A kind of Pointing Control System and pointing control method of wireless light communication |
| JP2019208233A (en) * | 2014-05-16 | 2019-12-05 | 株式会社Ｇｏｃｃｏ． | Visible light communication system |
| CN110568568A (en) * | 2015-01-08 | 2019-12-13 | 阿卡西亚通信有限公司 | Transmissive transmission paths on photonic circuits for optical alignment |
-
2020
- 2020-01-15 CN CN202010042513.4A patent/CN111416661B/en not_active Expired - Fee Related
Patent Citations (18)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101001110A (en) * | 2006-12-31 | 2007-07-18 | 桂林电子科技大学 | Radio laser scanning communication method |
| CN101140422A (en) * | 2007-08-20 | 2008-03-12 | 上海微电子装备有限公司 | Mask alignment making and aligning used for light scribing device |
| CN102571204A (en) * | 2011-12-09 | 2012-07-11 | 西安电子科技大学 | Optical transmitting antenna system and beam control method thereof |
| CN103560832A (en) * | 2013-11-15 | 2014-02-05 | 哈尔滨工业大学 | Feedback type light source aligning control method in white light communication |
| CN103675795A (en) * | 2013-12-20 | 2014-03-26 | 中国科学技术大学 | Device and method for automatically matching laser radar receiving and transmitting optical axes |
| CN103916183A (en) * | 2014-04-16 | 2014-07-09 | 电子科技大学 | Fast acquisition system and method based on laser phased technology |
| JP2019208233A (en) * | 2014-05-16 | 2019-12-05 | 株式会社Ｇｏｃｃｏ． | Visible light communication system |
| CN104320182A (en) * | 2014-09-30 | 2015-01-28 | 中国电子科技集团公司第四十一研究所 | Device and method for calibrating consistency of emission shaft and receiving shaft of space optical communication system |
| CN104618015A (en) * | 2015-01-04 | 2015-05-13 | 西安应用光学研究所 | Small atmosphere laser communication device and method |
| CN110568568A (en) * | 2015-01-08 | 2019-12-13 | 阿卡西亚通信有限公司 | Transmissive transmission paths on photonic circuits for optical alignment |
| CN105021526A (en) * | 2015-08-04 | 2015-11-04 | 安徽皖仪科技股份有限公司 | Laser gas analyzer with automatic light path alignment function |
| CN105510230A (en) * | 2016-01-15 | 2016-04-20 | 中国人民解放军理工大学 | System and method for automatically collimating measuring light path of transmission instrument based on scanning mode |
| US20170244482A1 (en) * | 2016-02-24 | 2017-08-24 | Qualcomm Incorporated | Light-based communication processing |
| US9853740B1 (en) * | 2017-06-06 | 2017-12-26 | Surefire Llc | Adaptive communications focal plane array |
| CN109450532A (en) * | 2018-12-27 | 2019-03-08 | 中国电子科技集团公司第三十四研究所 | With the wireless light communication tracking system for being directed toward correction and it is directed toward antidote |
| CN109831798A (en) * | 2019-03-26 | 2019-05-31 | 惠州Tcl移动通信有限公司 | Signal acquiring method, system, storage medium and mobile terminal |
| CN110233664A (en) * | 2019-04-25 | 2019-09-13 | 西安理工大学 | A kind of Pointing Control System and pointing control method of wireless light communication |
| CN110233665A (en) * | 2019-05-28 | 2019-09-13 | 西南电子技术研究所（中国电子科技集团公司第十研究所） | Radio frequency/laser collaboration fast Acquisition tracks alignment methods |
Non-Patent Citations (2)
| Title |
|---|
| CHENGKUN CAI等: "Experimental Demonstration of an Underwater Wireless Optical Link Employing Orbital Angular Momentum (OAM) Modes with Fast Auto-Alignment System", 《2019 OPTICAL FIBER COMMUNICATIONS CONFERENCE AND EXHIBITION (OFC)》 * |
| 张亮等: "星地量子通信光链路的建立与在轨验证", 《中国科学:信息科学》 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114900236A (en) * | 2022-07-15 | 2022-08-12 | 中北大学 | Line-of-sight space optical bidirectional communication system and method based on BOSA |
| CN114900236B (en) * | 2022-07-15 | 2022-09-27 | 中北大学 | Line-of-sight space optical bidirectional communication system and method based on BOSA |
Also Published As
| Publication number | Publication date |
|---|---|
| CN111416661B (en) | 2021-06-29 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US11550056B2 (en) | Multiple pixel scanning lidar | |
| US10613225B2 (en) | Distance measuring device | |
| CN104914445B (en) | For the combined type scanning system of laser radar | |
| CN111416661B (en) | Light path alignment method for space optical communication | |
| CN109387354B (en) | Optical scanner testing device and method | |
| CN112098337B (en) | High-resolution spectrum image rapid acquisition device and method | |
| CN109005340A (en) | The Atomatic focusing method and device of image definition curve matching are carried out based on least square method | |
| CN103645471A (en) | Laser radar detecting light source divergence angle measuring device and method | |
| CN102564343B (en) | Detection device for surface-shape errors of solar trench type curved surface reflector | |
| CN109085695A (en) | A method of it takes pictures for planar sample rapid focus | |
| CN110888144A (en) | Laser radar data synthesis method based on sliding window | |
| CN113163122B (en) | Focusing method | |
| CN110057839A (en) | Focusing control apparatus and method in a kind of Optical silicon wafer detection system | |
| CN106131436B (en) | A kind of the focusing test device and focusing test method of aerial camera | |
| CN109246340B (en) | Light field image processing and displaying system and method | |
| CN105651699A (en) | Dynamic focus following method based on area-array camera | |
| US7492398B1 (en) | Three-dimensional input apparatus and image sensing control method | |
| CN105259743A (en) | Automatic detection device and detection method of varifocal time of electronic control varifocal lens | |
| CN113970424A (en) | Lens zooming consistency dynamic deviation rectifying method and system under automatic tracking mode | |
| CN111854604B (en) | Method and system for measuring shape and position parameters of air film hole by focusing laser beam | |
| CN115184954A (en) | Radar system and method for detecting atmospheric coherence length and turbulence profile | |
| CN205049865U (en) | Automatic detection apparatus for automatically controlled zoom lens time of zooming | |
| CN113589316A (en) | N-line laser radar scanning system and method | |
| CN209640614U (en) | The system for drawing optical antenna outgoing beam optical axis | |
| CN113794828A (en) | Automatic focusing method and system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20210629 |
|
| CF01 | Termination of patent right due to non-payment of annual fee |