CN105049126A - Optical phase modulated signal transmission plan based on multi-polarization state - Google Patents
Optical phase modulated signal transmission plan based on multi-polarization state Download PDFInfo
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- CN105049126A CN105049126A CN201510467916.2A CN201510467916A CN105049126A CN 105049126 A CN105049126 A CN 105049126A CN 201510467916 A CN201510467916 A CN 201510467916A CN 105049126 A CN105049126 A CN 105049126A
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Abstract
The invention discloses an optical phase modulated signal transmission plan based on a multi-polarization state. A wavelength division multiplexer (102) combines a plurality of multi-polarization state multiplexing phase-modulated signals MPDM (1011 to 101N) with different wavelengths into a wavelength division multiplexing MPDM after being transmitted to a central office, and multiplexed optical signals are amplified via an optical amplifier (103) and are transmitted in an optical fiber (104) after performing power compensation; in a receiving end, the multiplexed optical signals are separated by a wavelength division demultiplexer (105) into N independent multi-polarization state multiplexing signals, and then each MPDM signal is received via a corresponding coherent receiver (106N) and is input to a digital signal processing unit (107). The digital signal processing demodulates the signal via a corresponding algorithm. Compared with a traditional orthogonal polarization multiplexing (PDM) solution, the transmission plan of the invention achieves the simultaneous transmission and demultiplexing of three polarization state multiplexing signals, and increases the message capacity in multiples and reduces the cost, while ensuring the flexibilities of a transmitting end and a receiving end in the optical network.
Description
Technical field
The present invention relates to short distance Access Network and the intercity net field of middle and long distance, especially a kind of light phase modulation Signal transmissions scheme based on multi-polarization state.
Background technology
Along with the quickening of the information-based paces of Chinese society, cloud computing, large data, the Internet+etc. concept slowly enter the life of people.Meanwhile, the explosive growth of amount of information requires improving constantly of message capacity.Optical fiber communication, as the foundation stone of modern communications, is widely used in the fields such as transoceanic communication, backbone network, intercity network.Coherent optical communication achieves the commercialization of Single wavelength 100Gbit/s optical communication system, and the system of following 400Gbit/s is also in slowly realizing.Present stage, along with the development of the technology such as ultra dense wavelength division multiple (DWDM), space division multiplexing (SDM), OFDM (OFDM) and palarization multiplexing (PDM), the Networks of Fiber Communications of P bit levels has obtained very ripe research in laboratory.In all these technology, the exploitation again of polarization state dimension is considered to one of technology of most potentiality.Its reason is, polarization state is a relatively independent dimension, can good and other technical compatibility.When applying to actual scene, this technology under the prerequisite keeping existing equipment, can complete significantly improving of data capacity.This is just for greatly to reduce upgrade cost, and the low cost, the sustainable operation that realize existing communication network provide possibility.
As far back as the mid-eighteenth century, the scholar such as Fresnel has done large quantity research to the polarization state characteristic of light wave.Polarisation-multiplexed signal transmission in a fiber and demultiplexing is just achieved to people such as nineteen ninety A.D.Kersey.But until after the group that Li Gui in 2005 virtue is led proposes effective Digital Signal Processing (DSP) algorithm, this technology just slowly maturation start to apply in business system widely.During this period, scientist has all over the world carried out system to this technology and has in depth studied.Wherein French researcher CI.Herard and A.Lacourt in 1986 proposes light and transmits the idea of three polarization states in free space and the reliability of this system under experimental verification low rate.Because this system is unsuitable for high rate data transmission, further do not developed.Southwest Jiaotong University Yan Lianshan in 2013 teaches research group and proposes the theoretical model that 4 polarization states based on coherent demodulation transmit simultaneously, the simulating, verifying feasibility of this model.The people such as Denmark scholar Jos é Estar á n in 2014 achieve four transmission of polarization state multiplexing optical signal in 2km optical fiber based on Stokes Space.The method structure is simple, but is only applicable to OOK signal and is not verified in comparatively long range propagation.Therefore study multi-polarization state, long distance, two-forty multiplexing and demultiplexer systems there is theoretical direction and practical application meaning.
Summary of the invention
In view of the above shortcoming of prior art is with not enough, the invention provides a kind of light phase modulation Signal transmissions scheme based on multi-polarization state, the program, when not increasing transmitter, receiver and algorithm complex, is transmitted while achieving multiple polarisation-multiplexed signal.For three polarization state multiplexing schemes, this programme utilizes coherent reception equipment, is realized the phase tracking of information in respective polarization state, thus realize the demultiplexing of multi-polarization state by the phase information extracting Received signal strength.Program principle is applicable to all psk signals.
The object of the invention is to analyze and scheme proposes and realization based on following:
Based on a light phase modulation Signal transmissions scheme for multi-polarization state, form primarily of the following device linked along light path order: a road or N road multi-polarization state (polarization state number>=3) multiplexing phase modulated optical signal (101
1~ 101
n), light wavelength division multiplexing 102, image intensifer 103, one section of optical fiber 104, Wave decomposing multiplexer 105, or a N number of coherent receiver (106
1~ 106
n)and a digital signal processing unit 107; The multiplexing phase modulated signal of multi-polarization state (MPDM, 101 that multichannel wavelength is different
1~ 101
n) pass to central office after, synthesized the MPDM of a wavelength division multiplexing by a wavelength division multiplexer (102); After power back-off is carried out in amplifier 103 amplification of optical signals after multiplexing, enter in one section of optical fiber 104 and transmit; At receiving terminal, first multiplexed signals is separated into N road independently multi-polarization state multiplexed signals by a Wave decomposing multiplexer 105, and then each road MPDM signal is again by corresponding coherent receiver 106
nreceive and be input to digital signal processing unit 107, in digital signal processing unit by corresponding algorithm by signal receiving out.
Adopt method of the present invention, comprise following feature: the polarization angle 1) between three polarization state signals can be greater than some specific low-angle arbitrarily angled; 2) do not need to know accurate multiplex angle, this programme can realize the polarization demultiplexing of signal adaptively; 3) the coherent receiver structure that demodulation adopts has larger compatibility to existing network formation.Existing PDM system can apply in commercial system well, but the exploitation of polarization dimension stays cool always.Its chief reason is the exploitation that most of researchers are still confined to orthogonal system, so just polarization state resource is limited to widely within two.And this programme principal character is to break traditions thinking, achieving the demultiplexing of the palarization multiplexing psk signal of more than three, having done theory study and deposit for increasing transmission capacity scheme further.Described scheme can be combined with other multiplex techniques, and as wavelength division multiplexing (WDM), OFDM (OFDM) etc., to realize the next generation network construction of low cost, Large Copacity, dynamic self-adapting.
Based on the light phase modulation Signal transmissions scheme of multi-polarization state, structure and the existing commercial transmission scheme of transmitter terminal and receiver are similar, therefore can carry out compatibility and upgrading to existing network well.Wherein, the generation of the multi-polarization state multiplexed signals of transmitting terminal, only needs by multiple Polarization Controller and a coupler, and signal is together multiplexing with different polarization angles; At receiver end, employing present stage, widely used coherent receiver was as receive mode, obtained signal of telecommunication E
xi, E
xq, E
yiand E
yq.Then the solution utilizing real-time DSP signal transacting can realize multi-polarization state multiplexed signals is in harmonious proportion to be recovered.Wherein the demodulation of signal is mainly divided into three steps: first utilize existing ripe algorithm to do resampling and clock recovery to received signal; Then the viterbi algorithm of improvement phase place is to received signal used to correct; Finally convert time-domain signal to phase information and follow the trail of, to do corresponding judgement thus to realize signaling protein14-3-3.
The present invention is applicable to short distance Access Network Signal transmissions, and is applicable to the transmission of the intercity network signal of middle and long distance.Simultaneously can be mutually compatible with the advanced multiplex mode such as WDM, OFDM; Compared with conventional orthogonal polarization multiplexing, present invention achieves the transmission of multi-polarization state multiplexed signals, adding entire system can message capacity; Compared with existing multi-polarization state multiplex mode, the present invention has that structure is simple, algorithm complex is low and the advantage such as transmission range is longer.
Accompanying drawing illustrates:
Fig. 1 is the light phase modulation Signal transmissions scheme based on multi-polarization state in the present invention;
Fig. 2 is that in the present invention, multi-polarization state multiplexed signals produces structure chart;
Fig. 3 is multi-polarization state multiplexed signals phase mapping figure in the present invention;
Fig. 4 is the basic comprising structure chart of coherent receiver in the present invention;
Fig. 5 is digital signal processing algorithm schematic diagram in the present invention;
Fig. 6 is the multiplexed signals phase information of hemoglobin absorptions fore-and-aft survey in the present invention, wherein schemes the phase information that (a) and (c) represent Ex and Ey after coherent reception respectively; Figure (b) and (d) represent Ex, Ey phase information after hemoglobin absorptions respectively;
Fig. 7 is in the present invention, back-to-back with 0 degree of polarization state, 30 degree of polarization state ber curve figure after 80 km transmission.
Embodiment
Below in conjunction with accompanying drawing, the invention will be further described.
As shown in Figure 1, the present invention program is by a road or N road multi-polarization state (polarization state number>=3) multiplexing phase modulated optical signal 101
1~ 101
n, light wavelength division multiplexing 102, image intensifer 103, one section of optical fiber 104, Wave decomposing multiplexer 105, or a N number of coherent receiver 106
1~ 106
nand Digital Signal Processing list (107 compositions.The transmitter and receiver structure of this programme is simple, mature and reliable, in the Access Network being applicable to short-distance transmission and the intercity network of middle and long distance.Concrete logical relation is as follows: the multiplexing phase modulated signal of multi-polarization state (MPDM, 101 that multichannel wavelength is different
1~ 101
n) pass to central office after, synthesized the MPDM of a wavelength division multiplexing by a wavelength division multiplexer 102; After power back-off is carried out in amplifier 103 amplification of optical signals after multiplexing, enter in one section of optical fiber 104 and transmit; At receiving terminal, first multiplexed signals is separated into N road independently multi-polarization state multiplexed signals by a Wave decomposing multiplexer 105, and then each road MPDM signal is again by corresponding coherent receiver 106
nthe light signal received is converted to I, Q signal of telecommunication, enters digital signal processing unit 107.Finally utilize I, time-domain information is converted into phase information by Q signal, to correct and judgement scheduling algorithm completes the recovery of the transmitting terminal signal of telecommunication through resampling, clock recovery, phase place.
Fig. 2 is that multi-polarization state multiplexed signals of the present invention produces structure chart.Production process and traditional PDM similar, enter into coupler after only needing that polarization angle is adjusted each via a Polarization Controller in N road phase modulated signal (N≤3), the signal of output is multi-polarization state multiplexed signals.Wherein, the relative phase in multi-polarization state multiplexed signals between each independent polarization state should keep stable as far as possible.
Fig. 3 is multi-polarization state multiplexed signals phase mapping figure in the present invention.For three polarization states, polarization state 1 light signal and polarization state 2 light signal are modulated to bpsk signal by intensity modulator respectively, because coupler effect makes polarization state 1 signal and polarization state 2 signal form phase quadrature, make the phase rotating 90 of polarization state 2 signal, this process as shown in phantom in FIG..After coupler, polarization state 2 signal portions power to be mapped in polarization state 1 and to generate coupled signal 1.In like manner, polarization state 2 signal portions power to be mapped in polarization state 3 and to generate coupled signal 2.
Fig. 4 is the basic comprising structure chart of the present invention's coherent receiver used, and the receiver of its structure and existing commercial coherent reception system is basically identical.First input signal is divided into two paths of signals by a polarization beam apparatus; Each road signal does Frequency mixing processing with local oscillator light respectively in 90 degree of optical mixers, obtains correspondingly I, Q signal; Light signal is converted into the signal of telecommunication through balanced detector by the I finally exported by frequency mixer, Q signal, is expressed as: E
xi, E
xq, E
yiand E
yq.
Fig. 5 is signal processing algorithm schematic diagram of the present invention.Still for three polarization states, the polarization angle of multiplexed signals is respectively 0 degree, 30 degree and 90 degree.After coherent receiver exports, the real time oscilloscope being 80GS/s through over-sampling rate realizes the discretization of signal and the acquisition of data.In order to obtain the good sampled point of effect, need to do resampling process to signal before processing signal.In the process, clock recovery also needs to take into account.Due to the impact of laser linewidth, there is certain relative jitter in the phase information of signal.Therefore, the present invention adopts the viterbi algorithm of improvement to do corresponding rectification to signal.It should be noted that correcting process carries out in time domain.After completing this step, signal will change into phase information from time domain, the present invention Pha
xwith Pha
yrepresent the phase information that 0 degree of polarization state and 90 degree of polarization state time domain datas are tried to achieve.At receiving terminal, one of them polarization state that the present invention can make optically and electrical domain digital signal processing algorithm aligns.Be generally 0 degree of polarization state or be 90 degree of polarization states, under the condition of alignment 0 degree of polarization state, demultiplexing process is described below.Whole demultiplexing process is divided into two parts: (one), for 90 degree of polarization states, average to the phase place of all data, obtains decision signal P
1.If Pha
y>P
1, then judge 90 degree of polarization state carried signals at this point as 1, on the contrary Pha
y<P
1time, then judge 90 degree of polarization state carried signals at this point as 0.So just can by the signal receiving entrained by 90 degree of polarization states out; (2), for 0 degree of polarization state, all data phases are averaged, obtain decision signal P
2.In like manner, according to Pha
x>P
2judge that 0 degree of polarization state carried signal is put as 1 at this and these data are kept at variable Pha
x1in, according to Pha
x<P
2judge that 0 degree of polarization state carried signal is put as 0 at this and these data are kept at variable Pha
x2in.Try to achieve Pha
x1, Pha
x2average be set to P respectively
3, P
4.If P
4<Pha
x<P
3, then 30 degree of polarization state carried signals are judged at this point as 1.If Pha
x>P
3or Pha
x<P
4, then 30 degree of polarization state carried signals are judged at this point as 0.So far, whole demodulating process completes, and the data after demodulation is done computing cross-correlation to transmitting terminal pseudo-random data and tries to achieve the ber curve of this system through corresponding computing.
Fig. 6 is the multiplexed signals phase information of hemoglobin absorptions fore-and-aft survey in the present invention, wherein schemes (a) and (c) and represents E after coherent reception respectively
yand E
xphase information; Figure (b) and (d) represent the E after hemoglobin absorptions respectively
y, E
xphase information.The power being mapped to (0 ° and 90 °) in two other polarization state due to 30 degree of polarization states is inconsistent, and the phase information of last synthesis also be there are differences.As shown in figure (a) and (c), map crosstalk when 30 degree of polarization states are mapped to 0 degree of polarization state large; It is little that 30 degree of polarization states map crosstalk when being mapped to 90 degree of polarization states.And before phase information is corrected, there is certain shake up and down in it.Like this, be just difficult to find a reasonable decision signal in judgement part.After respective algorithms is corrected, and demodulating algorithm described in conjunction with Figure 5, P can be judged very easily
1, P
2, P
3and P
4these four decision thresholds, thus demodulate signal respective in three polarization states.
Fig. 7 be the present invention when back-to-back with transmission 80 kilometers, the error rate figure of 0 degree of polarization state and 30 degree of polarization state carried signals.FEC: forward error correction coding.Use forward error correction (FEC) threshold value of 7% for contrast in figure, represent that any error rate lower than this threshold value can revert to without bit error signal.As seen from the figure, under the same error rate compared with back-to-back, after 80 km transmission, receiving terminal power only has about 3dB cost.
Can be observed by above experimental result, the present invention is based on the multiplexing and demultiplexing that phase information successfully achieves three polarization state multiplexed signalss.The program achieves the exploitation again of polarization state dimension to a certain extent, makes spectrum efficiency improve 1/2 times.Meanwhile, only need to do a small amount of improvement to existing transmission system transmitting terminal and receiving terminal.On basis of the present invention, can carry out demultiplexing to multi-polarization state multiplexed signals, making to significantly improve spectrum efficiency in original transmission system becomes possibility.Due to features such as digital signal processing algorithm of the present invention are simple, compatibility is good, be suitable for the transmission of short distance Access Network Signal transmissions of future generation and the intercity network signal of middle and long distance.
Claims (4)
1. based on a light phase modulation Signal transmissions scheme for multi-polarization state, it is characterized in that, form primarily of the following device linked along light path order: a road or the multiplexing phase modulated optical signal (101 of N road multi-polarization state
1~ 101
n), a light wavelength division multiplexing (102), an image intensifer (103), one section of optical fiber (104), a Wave decomposing multiplexer (105), one or N number of coherent receiver (106
1~ 106
n) and a digital signal processing unit (107); The multiplexing phase modulated signal of multi-polarization state (MPDM, 101 that multichannel wavelength is different
1~ 101
n) pass to central office after, synthesized the MPDM of a wavelength division multiplexing by a wavelength division multiplexer (102); After power back-off is carried out in amplifier (103) amplification of optical signals after multiplexing, enter transmission in one section of optical fiber (104); At receiving terminal, first multiplexed signals is separated into N road independently multi-polarization state multiplexed signals by a Wave decomposing multiplexer (105), and then each road MPDM signal is again by corresponding coherent receiver (106
n) receive and be input to digital signal processing unit (107), in digital signal processing unit by corresponding algorithm by signal receiving out.
2. a kind of light phase modulation Signal transmissions scheme based on multi-polarization state according to claim 1, it is characterized in that, the polarization state number transmitted is more than or equal to 3.
3. a kind of light phase modulation Signal transmissions scheme based on multi-polarization state according to claim 1 or 2, is characterized in that, the polarization angle of polarisation-multiplexed signal can be greater than a certain specific low-angle arbitrarily angled.
4. a kind of light phase modulation Signal transmissions scheme based on multi-polarization state according to claim 1 or 2 or 3, it is characterized in that, described phase modulation format signal comprises BPSK, QPSK etc. are changed to carrier various types of signal with phase place.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111901094A (en) * | 2020-08-04 | 2020-11-06 | 西南交通大学 | Multi-span laser chaotic relay secret transmission system |
| CN113810116A (en) * | 2017-09-01 | 2021-12-17 | 华为技术有限公司 | Optical signal transmission system and optical signal transmission method |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2005099129A1 (en) * | 2004-04-08 | 2005-10-20 | Karayil Thekkoott Narayanan Ma | Method to design polarization arrangements for mimo antennas using state of polarization as parameter |
| CN101795159A (en) * | 2010-03-26 | 2010-08-04 | 武汉邮电科学研究院 | High-speed WDM (Wavelength Division Multiplexing) light communication system and method for resisting non-linearity effect in same |
| CN102355304A (en) * | 2011-07-20 | 2012-02-15 | 上海交通大学 | Ethernet wavelength division multiplexing system and transmitting terminal thereof |
| CN103124208A (en) * | 2013-02-28 | 2013-05-29 | 西南交通大学 | Multiple-input-multiple-output optical transmission scheme based on multiple polarizations |
-
2015
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Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2005099129A1 (en) * | 2004-04-08 | 2005-10-20 | Karayil Thekkoott Narayanan Ma | Method to design polarization arrangements for mimo antennas using state of polarization as parameter |
| CN101795159A (en) * | 2010-03-26 | 2010-08-04 | 武汉邮电科学研究院 | High-speed WDM (Wavelength Division Multiplexing) light communication system and method for resisting non-linearity effect in same |
| CN102355304A (en) * | 2011-07-20 | 2012-02-15 | 上海交通大学 | Ethernet wavelength division multiplexing system and transmitting terminal thereof |
| CN103124208A (en) * | 2013-02-28 | 2013-05-29 | 西南交通大学 | Multiple-input-multiple-output optical transmission scheme based on multiple polarizations |
Non-Patent Citations (1)
| Title |
|---|
| ZHIYU CHEN 等: "Transmission of multi-polarization-multiplexed signals Another freedom to explore?", 《OPTICS EXPRESS》 * |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113810116A (en) * | 2017-09-01 | 2021-12-17 | 华为技术有限公司 | Optical signal transmission system and optical signal transmission method |
| US11652553B2 (en) | 2017-09-01 | 2023-05-16 | Huawei Technologies Co., Ltd. | Optical signal transmission system and optical signal transmission method |
| CN111901094A (en) * | 2020-08-04 | 2020-11-06 | 西南交通大学 | Multi-span laser chaotic relay secret transmission system |
| CN111901094B (en) * | 2020-08-04 | 2021-10-22 | 西南交通大学 | Multi-span laser chaotic relay secret transmission system |
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