CN111147135B - High-capacity orbital angular momentum hybrid multiplexing communication method and test method thereof - Google Patents
High-capacity orbital angular momentum hybrid multiplexing communication method and test method thereof Download PDFInfo
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- 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
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- H—ELECTRICITY
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- 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
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- 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
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Abstract
The invention relates to a high-capacity orbital angular momentum hybrid multiplexing communication method and a test method thereof. The test method comprises the following steps: multiple paths of eddy optical rotation signals generated by Gaussian beams are sequentially subjected to orbital angular momentum multiplexing, polarization division multiplexing and frequency division multiplexing to be synthesized into a path of optical signal; emitting the multiplexed optical signal to an atmospheric turbulence, wherein the atmospheric turbulence is simulated by a multilayer phase screen; and measuring parameters of the communication. Compared with the traditional technology, the communication method provided by the invention can improve the communication capacity and speed.
Description
Technical Field
The invention relates to the technical field of communication, in particular to a high-capacity orbital angular momentum hybrid multiplexing communication method and a test method thereof.
Background
With the increasing popularity of the internet and the increasing development of the communication industry, the demand of people on the communication speed and capacity is also increasing, and the high-speed and high-capacity communication is a necessary trend of the future communication development.
At present, the multiplexing technology in communication includes wavelength division multiplexing, time division multiplexing, etc., but these multiplexing technologies still have communication rate and capacity far from meeting the development requirements of the emerging communication field. The provision of new communication multiplexing modes is also an urgent need for the development of the communication industry.
Disclosure of Invention
In view of the above, there is a need to provide a high-capacity orbital angular momentum hybrid multiplexing communication method, which can improve the communication capacity and rate compared to the conventional techniques.
A test method for high-capacity orbital angular momentum hybrid multiplexing communication comprises the following steps:
multiple paths of eddy optical rotation signals generated by Gaussian beams are sequentially subjected to orbital angular momentum multiplexing, polarization division multiplexing and frequency division multiplexing to be synthesized into a path of optical signal;
emitting the multiplexed optical signal to an atmospheric turbulence, wherein the atmospheric turbulence is simulated by a multilayer phase screen; and
parameters of the communication are measured.
The intensity of the atmospheric turbulence is positively correlated with the number of phase screens.
The refractive power spectrum of the atmospheric turbulence is Kolmogorov type.
The test method comprises the following steps:
and testing the influence of different transmission distances, atmospheric turbulence intensity and topological charge number on the phase.
The test method further comprises the following steps:
the bit error rate and the Q function of communication transmission are measured under different atmospheric turbulence intensities.
A high-capacity orbital angular momentum hybrid multiplexing communication method is applied to a sending end of communication and comprises the following steps:
the method comprises the steps of generating multi-channel vortex optical signals by utilizing Gaussian beams, synthesizing one optical signal by sequentially carrying out orbital angular momentum multiplexing, polarization division multiplexing and frequency division multiplexing, and sending the multiplexed one optical signal to a communication receiving end.
A high-capacity orbital angular momentum hybrid demultiplexing method is applied to a receiving end of communication and comprises the following steps:
receiving one path of multiplexed optical signals, and sequentially carrying out frequency division demultiplexing, polarization demultiplexing and orbital angular momentum demultiplexing to restore to obtain original multi-path vortex optical signals.
Including 32-way vortex optical signals.
Compared with the traditional technology, the invention adds the orbital angular momentum multiplexing and can improve the communication capacity and speed.
The hybrid multiplexing scheme provided by the invention can be combined with the existing frequency division multiplexing network and polarization multiplexing network, and has strong use value.
Drawings
Fig. 1 is a schematic structural diagram of a high-capacity orbital angular momentum hybrid multiplexing communication system and a schematic test scenario thereof in an embodiment of the present invention;
FIG. 2 is a comparison of spot size and offset angle in a test scenario of the present invention;
FIG. 3 is a schematic diagram of a test result of a topological charge number of +8 under a fixed turbulence intensity in a test scenario according to the present invention;
FIG. 4 is a light field and phase distribution of vortex light passing through different intensity turbulences in a test scenario of the present invention;
FIG. 5 shows the distribution of the optical field and phase of the vortex rotation with different topological charge numbers at a fixed turbulence intensity and a transmission distance of 2 km;
FIG. 6 is a comparison of transmission error rates in a test scenario of the present invention;
FIG. 7 is a spectral analysis of orbital angular momentum multiplexing communications in a test scenario of the present invention;
fig. 8 is a transmission eye diagram for different signal intervals and a received bit error rate for different turbulences.
Detailed Description
The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings. All other tools obtained by those skilled in the art without creative efforts based on the operation flow and the reinforcement method of the present invention belong to the protection scope of the present invention. The communication method, the demultiplexing method and the orbital angular momentum, polarization and frequency multiplexing mode combined multiplexing are protected by the patent. While the use of this method for communication under channels of atmospheric turbulence is protected by this patent.
As shown in fig. 1, a 32-track angular momentum multiplex communication system is constructed. The system is formed by orbital angular momentum, polarization and frequency multiplexing, and has a specific structure that every four vortex light beams are multiplexed into one light beam by the orbital angular momentum. Two four-way orbital angular momentum beams are combined together by polarization multiplexing. In the same manner, the remaining beam is subjected to the same process, and the 32-path beam is changed to have a beam structure of 8+8+8+ 8. And performing Frequency Division Multiplexing (FDM) on the four paths of composite orbital angular momentum beams. Finally, 32-track angular momentum multiplexing can be realized by using four frequencies, and the light beams are transmitted to the atmosphere through a telescope system.
At the receiving end, the signals of different frequencies are separated by frequency division demultiplexing. Each beam is made into a beam containing eight orbital angular momenta of polarization multiplexing, and is made into a 4+4 beam by polarization demultiplexing. And then, demultiplexing the orbital angular momentum of each beam to realize the complete separation of 32 beams of light, so that each beam only contains one orbital angular momentum, and finally converting the optical signals into electric signals through a photoelectric detector. The system realizes 32-path multiplexing communication links by using OAM-POL-FDM joint multiplexing.
In orbital angular momentum multiplexing, different topological charges determine communication channels, and the change of the topological charges can influence the propagation of signals in the channels. We investigated the effect of different transmission distances, turbulence intensity, topological charge number on phase. The simulation was performed under the FSO turbulent channel, and as a result, the size of the spot gradually increased with increasing transmission distance under the same turbulence intensity, as shown in fig. 2 a. At the same distance, increasing the turbulent intensity spot size increases. This is because the medium is non-uniform in the atmosphere. Certain random refraction occurs when the light beam passes through the non-uniform atmosphere, so that the size of the light beam is increased and the power is reduced after the light beam is transmitted for a certain distance. This phenomenon can be improved by increasing the transmitted optical power, or by adding optics to concentrate the light at the receiving end. Meanwhile, because of random refraction, the light beam has a certain offset angle after being transmitted. As shown in fig. 2b, when the turbulence intensity is uniform, the offset angle gradually increases as the transmission distance increases. At equal distances, turbulence increases the offset angle.
Topology of charge ofVortex rotation of +8 at intensity Cn 2＝10-15m-2/3(medium turbulence) turbulence, the light field is affected to a different extent over different distances. As shown in fig. 3, the waveform may be distorted with transmission distance. With the increase of the transmission distance, the optical field of the vortex rotation is dispersed more and more, and the light spot size is larger and larger. The phase changes from the original regular distribution to a twisted helical phase distribution. If one wants to receive all the energy of the beam at the receiving end completely, a larger receiver size or a converging lens is needed. If the receiver aperture size is kept constant, the further the transmission distance, the less power the beam can enter the receiver and the greater the signal-to-noise ratio.
Fig. 4 shows the light field and phase obtained by the vortex light of l ═ 8 under different turbulence intensity and the same transmission distance. When the vortex beam passes through turbulence, the waveform is distorted. When the intensity of turbulence in a free-space optical channel is changed, its phase distortion becomes more and more pronounced as the turbulence increases. Turbulence intensity higher than Cn 2＝10-14m-2/3Its phase is almost indistinguishable. The turbulence intensity should be less than C when transmitting over a distance of 3kmn 2＝5×10-15m-2/3. The phase resolvability is ensured, and the signals can be separated according to the phase at the receiving end.
Under the same transmission distance and turbulence intensity, the light intensity distribution of the vortex light beam in the topological charge size link is changed as shown in figure 5. After the vortex light beam is transmitted in a long distance, the influence of turbulence on the vortex light beam with larger topological charge number is more obvious. Since the center of the vortex rotation is a phase singularity and the amplitude of the center is almost zero, the influence is relatively larger where the amplitude is smaller. In other words, the larger the topological charge number, the more the turbulence affects the phase of its central part, and the more the phase distortion of the central part is. So that the central portion of the beam, which is subject to a larger topological load, is subject to a greater influence of turbulence for the same distance transmitted at the same turbulence intensity.
In the transmission process, when the vortex light beam is influenced by turbulence, the vortex light with the original topological charge number forms a new topological charge number due to the distortion of the phaseVortex rotation causes crosstalk between vortex beams. The topological charge number of the vortex rotation is calculated according to the phase change times of 0-2 pi of the original optical field. We compare under different turbulence intensity, and the crosstalk situation of orbital angular momentum after the signal is transmitted through the turbulence channel is shown in fig. 6. When the light beam passes through the turbulent flow, the orbital angular momentum can be in crosstalk from l to n to nearby n + -1, n + -2 and …. The crosstalk causes the power of the original channel to decrease after the signal is transmitted for a long distance, and the noise of the signal affected by the crosstalk of the adjacent channels increases. FIG. 6.b shows the cross-talk of the signal in case of weak turbulence, passing through weak turbulence Cn 2＝10-16m-2/3At this time, 7.2% of the power crosstalked to the side channel. When in high turbulence Cn 2＝10-14m-2/3At this time, 46.8% of the power is crosstalking into the next channel, as shown in fig. 6. c. The stronger the turbulence intensity, the more severe the crosstalk and the more dispersed the energy distribution of the crosstalk out.
When two orbital angular momentums are multiplexed to transmit information, mutual interference occurs between different channels. Fig. 6.d-f shows that when two orbital angular momentums are transmitted simultaneously, there is about 7% of the energy crosstalk to other channels in case of weak turbulence. In case of strong turbulence, the channels have energy cross-talk to the next channels of 49.6% and 46.7%. Because the signal power is relatively dispersed under strong turbulence, the energy crosstalk from the a channel is superimposed with the power of the B channel nearby, and thus, the B channel information is affected. In other words, the stronger the turbulence, the more serious the crosstalk between channels, and the larger the signal-to-noise ratio of the signal due to the crosstalk. At the same time, when two vortex-rotating topological charges l in the channel1And l2Difference (l) of1-l2) As it becomes smaller, the crosstalk of the two channels becomes worse. This is because the probability of vortex-optically active crosstalk to a channel close to it is greater. Therefore, during normal communication, proper intervals should be kept between load channels of different topologies, so that the quality of signal transmission can be more effectively ensured.
The system is allowed to transmit signals, and under different turbulence intensities, the error rate and the Q function of the transmission are obtained, and the result is shown in figure 6. g. The data is in weak turbulence (C)n 2＝10-16m-2/3) Medium turbulence (C)n 2＝10-15m-2/3) Highly turbulent (C)n 2＝10- 14m-2/3) The transmission distance is set at 1km for the bit error rate case. As can be derived from the data, the error rate decreases gradually as the received power increases. When the turbulence increases, the bit error rate increases. Intensity of turbulence Cn 2＝10-14m-2/3And Cn 2＝10-15m-2/3The error rate between the two is 1.886 orders of magnitude different at most. Intensity of turbulence Cn 2＝10-15m-2/3And Cn 2＝10-16m-2/3The error rate between the two is 0.8776 magnitude difference at most.
The system adds frequency division multiplexing, and the influence of different frequency intervals on communication is compared. The system is in weak turbulence Cn 2＝10-16m-2/3In the case where the frequency intervals are set at three different levels of 0.5THz, 0.3THz and 0.1THz, respectively, a spectrum distribution diagram is obtained as shown in fig. 7. Power suppression can be 40.332dB at 0.5THz interval.
The signal is affected to a different extent at different frequency intervals. At a signal interval of 0.5THz, the receiving-end signal eye diagram is shown in fig. 8. a. When the signal interval is 0.1THz, the eye diagram of the receiving end signal is shown in fig. 8. b. As the frequency spacing is reduced, the waveform stability is degraded and the received signal error rate is increased. The signal transmission results are shown in fig. 8. c. The signal quality at interval 0.5THz would be better than at 0.3 THz. The signal quality at interval 0.3THz will be better than 0.1 THz. As the frequency interval decreases, the signal transmission quality is significantly affected and the error rate gradually increases. At the same frequency interval, turbulence increases the signal error rate. Therefore, even in the same orbital angular momentum multiplexing link, different frequency intervals and different turbulence intensities can affect the signal receiving error rate. By using the OAM-POL-FDM joint multiplexing system in atmospheric turbulence, the spectral efficiency is ensured, meanwhile, enough intervals are ensured, and meanwhile, the influence of the turbulence on communication is considered. To ensure that the OAM multiplexing signal can be demultiplexed, it is necessary to ensure that the phase of the receiving-end eddy current can be resolved. The transmission distance cannot exceed its resolvable limit transmission distance at the corresponding turbulence intensity.
In summary, the provided test method can generate mutual crosstalk between the multiplexed orbital angular momentum beams under the influence of turbulence. Under weak turbulence, 7.2% of the energy passes through the topological load conditions beside the detour. Under highly turbulent conditions, 46.8% of the energy is cross-talk to the next topological charge, and the more turbulent the cross-talk is, the more dispersed the energy distribution. When a plurality of topological charge states are transmitted simultaneously, a part of energy can leak to other topological charge states. In our study, 3% and% 1.6 crosstalk into the opposite channel becomes noise at 4 topological charges apart under high turbulence. In frequency division multiplexing, different frequency intervals also affect the system. When the interval is reduced from 0.5THz to 0.1THz, the eye pattern may be deteriorated. In the case of information transmission, in medium turbulence Cn 2＝10-15m-2/3And weak turbulence Cn 2＝10-16m-2/3The maximum difference of the error rates is 1.886 orders of magnitude, and strong turbulence Cn 2＝10-14m-2/3And medium turbulence Cn 2＝10-15m-2/3The maximum difference between the error rates is 0.8776 orders of magnitude. Turbulence has a serious impact on OAM communication. Vortex optical transmission with topological charge of +8 for 3km distance at Cn 2＝5×10-15m-2/3The phase is already completely distorted under turbulent intensity, so that the vortex light of l ═ 8 is in Cn 2＝10-15m-2/3At intensity, the beam travel distance must be less than 3 km. The phase resolvability is ensured, so that the signals can be separated according to different phases at the receiving end.
The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the present invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.
Claims (8)
1. A test method for high-capacity orbital angular momentum hybrid multiplexing communication is characterized by comprising the following steps:
synthesizing a plurality of eddy optical rotation signals generated by Gaussian beams into a path of optical signal through orbital angular momentum multiplexing, polarization division multiplexing and frequency division multiplexing in sequence;
emitting the multiplexed optical signal to an atmospheric turbulence, wherein the atmospheric turbulence is simulated by a multilayer phase screen; and
measuring parameters of the communication;
the method is characterized in that a plurality of eddy optical rotation signals generated by Gaussian beams are sequentially subjected to orbital angular momentum multiplexing, polarization division multiplexing and frequency division multiplexing to be synthesized into one path of optical signal, and specifically comprises the following steps:
building a 32-track angular momentum multiplexing communication system, wherein the system is formed by multiplexing of the angular momentum of the track, polarization and frequency; every four vortex light beams are multiplexed and synthesized into one light beam through orbital angular momentum, and two four paths of orbital angular momentum light beams are multiplexed and synthesized together through polarization; the rest beams are processed in the same way, so that the 32 paths of beams are changed into a beam structure of 8+8+8+ 8; then the four paths of composite orbital angular momentum beams are subjected to frequency division multiplexing; finally, 32-track angular momentum multiplexing can be realized by using four frequencies.
2. The method for testing high-capacity orbital angular momentum hybrid multiplexing communication according to claim 1, wherein the intensity of the atmospheric turbulence is positively correlated with the number of phase screens.
3. The method for testing high-capacity orbital angular momentum hybrid multiplexing communication according to claim 2, wherein the refractive power spectrum of the atmospheric turbulence is Kolmogorov type.
4. The method for testing high capacity orbital angular momentum hybrid multiplexing communication according to claim 3, wherein the method for testing comprises:
and testing the influence of different transmission distances, atmospheric turbulence intensity and topological charge number on the phase.
5. The method for testing high capacity orbital angular momentum hybrid multiplexing communication according to claim 3, further comprising:
the bit error rate and the Q function of communication transmission are measured under different atmospheric turbulence intensities.
6. A high-capacity orbital angular momentum hybrid multiplexing communication method is applied to a sending end of communication and comprises the following steps:
generating multi-channel eddy optical rotation signals by using a Gaussian beam, synthesizing one path of optical signals by orbital angular momentum multiplexing, polarization division multiplexing and frequency division multiplexing, and sending the multiplexed one path of optical signals to a communication receiving end;
the method is characterized in that a plurality of eddy optical rotation signals generated by Gaussian beams are sequentially subjected to orbital angular momentum multiplexing, polarization division multiplexing and frequency division multiplexing to be synthesized into one path of optical signal, and specifically comprises the following steps:
building a 32-track angular momentum multiplexing communication system, wherein the system is formed by multiplexing of the angular momentum of the track, polarization and frequency; every four vortex light beams are multiplexed and synthesized into one light beam through orbital angular momentum, and two four paths of orbital angular momentum light beams are multiplexed and synthesized together through polarization; the rest beams are processed in the same way, so that the 32 paths of beams are changed into a beam structure of 8+8+8+ 8; then the four paths of composite orbital angular momentum beams are subjected to frequency division multiplexing; finally, 32-track angular momentum multiplexing can be realized by using four frequencies.
7. A high-capacity orbital angular momentum hybrid multiplexing communication method is applied to a receiving end of communication and comprises the following steps:
receiving one path of multiplexed optical signals, and obtaining original multi-path vortex optical signals through frequency division demultiplexing, polarization demultiplexing and orbital angular momentum demultiplexing reduction in sequence;
the multi-channel eddy optical rotation signal generated by the Gaussian beam of the one-channel optical signal is synthesized by orbital angular momentum multiplexing, polarization division multiplexing and frequency division multiplexing in sequence, and specifically comprises the following steps:
building a 32-track angular momentum multiplexing communication system, wherein the system is formed by multiplexing of the angular momentum of the track, polarization and frequency; every four vortex light beams are multiplexed and synthesized into one light beam through orbital angular momentum, and two four paths of orbital angular momentum light beams are multiplexed and synthesized together through polarization; the rest beams are processed in the same way, so that the 32 paths of beams are changed into a beam structure of 8+8+8+ 8; then the four paths of composite orbital angular momentum beams are subjected to frequency division multiplexing; finally, 32-track angular momentum multiplexing can be realized by using four frequencies.
8. The high-capacity orbital angular momentum hybrid multiplexing communication method according to claim 6 or 7, wherein the method specifically comprises 32-channel vortex optical signals.
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103457659A (en) * | 2013-08-22 | 2013-12-18 | 华中科技大学 | Space division multiplex system and method suitable for free space optical communication |
| CN106788745A (en) * | 2016-11-25 | 2017-05-31 | 深圳大学 | A kind of orbital angular momentum be concerned with demultiplexing device and separation detection method |
| CN107634831A (en) * | 2017-10-25 | 2018-01-26 | 华南师范大学 | Quantum key distribution network system and method based on orbital angular momentum multiplexing |
| CN107707300A (en) * | 2017-09-26 | 2018-02-16 | 南京邮电大学 | A kind of method of the non-aligned OAM multiplex systems crosstalk of suppression based on RVP modulation |
| CN109768829A (en) * | 2019-01-09 | 2019-05-17 | 中南民族大学 | Atmospheric turbulance distortion compensating system and its method in orbital angular momentum optical transport |
| CN110120837A (en) * | 2019-04-08 | 2019-08-13 | 深圳大学 | A kind of device and method promoting vortex light spatial multiplexing communication system stability |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US10411811B2 (en) * | 2015-12-07 | 2019-09-10 | University Of Southern California | Systems and techniques for communication using combined orbital angular momentum and multiple-input-multiple-output processing |
| CN106357317A (en) * | 2016-12-06 | 2017-01-25 | 南通大学 | Method for restraining atmosphere turbulence interference in free-space optical communication |
| US10498449B2 (en) * | 2017-03-15 | 2019-12-03 | Nec Corporation | Secured hybrid coded modulation for 5G—and beyond—access networks |
| CN208156232U (en) * | 2018-04-18 | 2018-11-27 | 华南理工大学 | It is a kind of to support to stablize the optical fiber orbital angular momentum mode generator transmitted |
-
2019
- 2019-11-01 CN CN201911060399.1A patent/CN111147135B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103457659A (en) * | 2013-08-22 | 2013-12-18 | 华中科技大学 | Space division multiplex system and method suitable for free space optical communication |
| CN106788745A (en) * | 2016-11-25 | 2017-05-31 | 深圳大学 | A kind of orbital angular momentum be concerned with demultiplexing device and separation detection method |
| CN107707300A (en) * | 2017-09-26 | 2018-02-16 | 南京邮电大学 | A kind of method of the non-aligned OAM multiplex systems crosstalk of suppression based on RVP modulation |
| CN107634831A (en) * | 2017-10-25 | 2018-01-26 | 华南师范大学 | Quantum key distribution network system and method based on orbital angular momentum multiplexing |
| CN109768829A (en) * | 2019-01-09 | 2019-05-17 | 中南民族大学 | Atmospheric turbulance distortion compensating system and its method in orbital angular momentum optical transport |
| CN110120837A (en) * | 2019-04-08 | 2019-08-13 | 深圳大学 | A kind of device and method promoting vortex light spatial multiplexing communication system stability |
Non-Patent Citations (1)
| Title |
|---|
| ＯＦＤＭ－ＯＡＭ光信号在大气湍流中的传输;刘旻雯;《光学学报》;20190731;第39卷(第7期);全文 * |
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