CN104486277B - The update method of modulation-demo-demodulation method, system and adaptive-filtering coefficient - Google Patents
The update method of modulation-demo-demodulation method, system and adaptive-filtering coefficient Download PDFInfo
- Publication number
- CN104486277B CN104486277B CN201410811063.5A CN201410811063A CN104486277B CN 104486277 B CN104486277 B CN 104486277B CN 201410811063 A CN201410811063 A CN 201410811063A CN 104486277 B CN104486277 B CN 104486277B
- Authority
- CN
- China
- Prior art keywords
- eout
- ein
- polarization
- adaptive
- qpsk
- 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.)
- Active
Links
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
- H04B10/50—Transmitters
- H04B10/516—Details of coding or modulation
- H04B10/5161—Combination of different modulation schemes
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B10/00—Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication
- H04B10/50—Transmitters
- H04B10/516—Details of coding or modulation
- H04B10/548—Phase or frequency modulation
- H04B10/556—Digital modulation, e.g. differential phase shift keying [DPSK] or frequency shift keying [FSK]
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L27/00—Modulated-carrier systems
- H04L27/18—Phase-modulated carrier systems, i.e. using phase-shift keying
- H04L27/20—Modulator circuits; Transmitter circuits
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L27/00—Modulated-carrier systems
- H04L27/18—Phase-modulated carrier systems, i.e. using phase-shift keying
- H04L27/22—Demodulator circuits; Receiver circuits
- H04L27/227—Demodulator circuits; Receiver circuits using coherent demodulation
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Digital Transmission Methods That Use Modulated Carrier Waves (AREA)
- Optical Communication System (AREA)
Abstract
The invention discloses the update method of a kind of polarisation shift keying modulation demodulation method, system and receiving terminal adaptive-filtering coefficient, polarisation shift keying modulation demodulation method includes：In transmitting terminal, using QPSK mode, any QPSK signals are modulated on X polarization directionsOn Y polarization directions, it is modulated into and X polarization signals according to input signal S (n)Identical or opposite Y polarization signalsIn receiving terminal, use palarization multiplexing QPSK mode by receiving signal demodulation for corresponding electric signal, then sampled again with ADC, quantify after carry out Digital Signal Processing and restore input signal S (n), Digital Signal Processing updates adaptive filter coefficient using improved CMA methods.The present invention, is immunized phase noise, and reduce the advantage of nonlinear fiber influence with polarisation shift keying, it can be played a significant role in overlength span transmission, also, send the ripe hardware structure that reception signal inherits palarization multiplexing QPSK completely, realize simply, with very strong practicality.
Description
Technical field
The present invention relates to coherent light communication, and in particular to polarisation shift keying modulation demodulation method, system and receiving terminal
The update method of adaptive-filtering coefficient.
Background technology
The theory of coherent light communication and experiment start from the eighties, are acknowledged as with the high advantage of sensitivity, coherent light leads to
Letter also has the characteristics of frequency selectivity is good, spectrum efficiency is high, and these features are conducive to the raising of message capacity.In addition, relevant
In optic communication, the damage of dispersion and polarization mode dispersion to signal is all linear damage, when now communication channel can be modeled as linear
Invariant system.Therefore can by complicated DSP (Digital Signal Processing, the Digital Signal Processing) technology of appropriateness
To compensate linear damage, the chromatic dispersion problem of puzzlement industry became relatively easy solution in the past.As optic communication enters 40G, 100G
Epoch, coherent light communication is combined with Digital Signal Processing, and obtains huge business success.
Consider the requirement of spectrum efficiency and OSNR tolerance limit, what the 100G commercial systems based on coherent light communication were used
It is PM-QPSK (Polarization Multiplexed Quadri Phase Shift Keying, the phase shift key of palarization multiplexing four
Control) technology.But in real network, the wavelength channel even optical fiber in optical fiber is not used fully.And in overlength span system
In system, spectrum efficiency is simultaneously less important, can use the modulation format of more low order.
The non-relay optical transmission system of overlength span, i.e., in addition to two ends, centre is without using any EDFA (Erbium-
Doped Optical Fiber Amplifier, active-fibre optical amplifier).In some special occasions, such as marsh, desert, forest
Deng in depopulated zone, or communication over strait, active-fibre optical amplifier can bring huge construction, operation maintenance cost, and overlength span is without in
There is significant cost advantage after optical transmission system.
Realize overlength span, it is desirable to the bigger laser power of injection fibre, but excessive injection laser power can increase
Nonlinear impairments.Therefore overlength span system needs the stronger modulation format of anti-nonlinear impairments ability.For example, due to 2-BPSK
The phase distance of (2-Binary Phase Shift Keying, binary phase shift keying) constellation point is higher than mono- times of QPSK, more can
Phase distortion caused by nonlinear effect is resisted, so being more suitable for overlength span transmission than QPSK.
In light wave, in addition to amplitude, frequency, phase, the direction of electric field intensity can also be used for modulation intelligence.POLSK
(polarization shift keying, polarisation shift keying) carries the modulation format of information with the polarization state of optical signal,
POLSK technologies have immune phase noise, and can reduce the characteristics of nonlinear fiber influences, but traditional POLSK requires to receive
Hold to quasi-optical polarization state, and due to the random change of polarization state in fiber channel, therefore require using complicated polarization tracking device,
So POLSK does not have been used in a large scale.
In summary, there are the following problems for existing POLSK technologies：
(1) implement more complicated；
(2) practicality is not strong.
The content of the invention
Problem to be solved by this invention is that existing POLSK technologies implement that more complicated and practicality is not strong to ask
Topic.
In order to solve the above-mentioned technical problem, the technical solution adopted in the present invention is to provide a kind of receiving terminal adaptive-filtering
The update method of coefficient, comprises the following steps：
To X polarized reception signals [Einx] and Y polarized reception signals [Ein (n-l)y(n-l) time domain equalization] is carried out；
It is filtered using equation below：
Wherein：
EoutxAnd Eout (n)y(n) it is respectively the defeated of sef-adapting filter X polarized receptions signal and Y polarized reception signals
Go out, Fxx、Fxy、Fyx、FyyFor four adaptive filter coefficients, n is sequence number, and L is sef-adapting filter series, and l is adaptive
Filter order sequence number；
F is updated using gradient algorithmxx、Fxy、Fyx、FyyValue, converges to the value during minimum value of error ε automatically：ε's determines
Justice is：
εx={ 1-Eoutx(n)[Eoutx(n)]*}；
εy={ 1-Eouty(n)[Eouty(n)]*}；
εxy={ 2- [Eoutx(n)+jEouty(n)][Eoutx(n)+jEouty(n)]*}；
Corresponding coefficient update algorithm is.
Fxx(l, g+1)=Fxx(l,g)+4μ1εxEoutx(n)[Einx(n-l)]* +4μ2εxy[Eoutx(n)+jEouty(n)]
[Einx(n-l)]*；
Fxy(l, g+1)=Fxy(l,g)+4μ1εxEoutx(n)[Einy(n-l)]* +4μ2εxy[Eoutx(n)+jEouty(n)]
[Einy(n-l)]*；
Fyx(l, g+1)=Fyx(l,g)+4μ1εyEouty(n)[Einx(n-l)]*- 4 μ2εxyj[Eoutx(n)+jEouty
(n)][Einx(n-l)]*；
Fyy(l, g+1)=Fyy(l,g)+4μ1εyEouty(n)[Einy(n-l)]* -4μ2εxyj[Eoutx(n)+jEouty
(n)][Einy(n-l)]*；
* it is conjugate of symbol, g represents the small coefficient needed to use according to the g times renewal, μ 1, and span can be
1-10-9, j is complex symbol.
Present invention also offers a kind of polarisation shift keying modulation demodulation method, comprise the following steps：
In transmitting terminal, using QPSK mode, any QPSK signals are modulated on X polarization directions inclined as X
Shake signalOn Y polarization directions, it is modulated into and X polarization signals according to input signal S (n)Identical or opposite Y is inclined
Shake signal
When S (n)=0
When S (n)=1
Wherein：
Input signal S (n) represents the binary data to be transmitted, and n is sequence number；
In receiving terminal, use palarization multiplexing QPSK mode by receiving signal demodulation for corresponding electric signal, so
Sampled, quantified with ADC again afterwards, finally carried out Digital Signal Processing and restore input signal S (n)；
The process of Digital Signal Processing includes successively：Dispersion compensation, clock recovery, adaptive-filtering, coherent detection, code element
Judgement and differential decoding, wherein adaptive-filtering are real using the update method of above-mentioned adaptive-filtering coefficient by linear equalizer
It is existing.
In the above-mentioned methods, after sef-adapting filter is restrained, output signal is：
Cos (α), sin (α) represent the coefficient that any quadratic sum is equal to 1, and α is any angle, and j is complex symbol, and j ω t are
Sending and receiving end frequency difference and the product of time, j θXYIt can be random angle angle value.
In the above-mentioned methods, input signal S (n) is recovered using below equation：
Wherein：± two ambiguous solutions are represented, it can be eliminated by difference encoding and decoding.
Present invention also offers a kind of polarisation shift keying modulation demodulating system, including transmitting terminal and receiving terminal：
The transmitting terminal is provided with modulating unit, and the modulating unit uses QPSK mode, in X polarization directions
On modulate any QPSK signals as X polarization signalsOn Y polarization directions, it is modulated into according to input signal S (n) and X
Polarization signalIdentical or opposite Y polarization signals
When S (n)=0
When S (n)=1
Wherein：
Input signal S (n) represents the binary data to be transmitted, and n is sequence number；
The receiving terminal is provided with demodulating unit and digital signal processing unit, and the demodulating unit is orthogonal using palarization multiplexing
Receiving signal demodulation is corresponding electric signal, then restores input by the digital signal processing unit by phase-shift keying (PSK) mode
Signal S (n), the digital signal processing unit is provided with sef-adapting filter, and the sef-adapting filter uses the above method
Carry out the renewal of adaptive-filtering coefficient.
There is the present invention polarisation shift keying phase noise is immunized, and resist certain nonlinear effect, and reduce optical fiber non-thread
Property influence advantage, and can the linear damage such as effective compensation dispersion, PMD, the change of automatic compensating polarizing state can be in overlength span
Played a significant role in transmission.Also, send and receive the ripe hardware structure that signal inherits palarization multiplexing QPSK completely, realize letter
It is single, with very strong practicality.
Brief description of the drawings
Fig. 1 is polarisation shift keying modulation demodulation method flow chart provided in an embodiment of the present invention；
Fig. 2 is the flow chart of Digital Signal Processing provided in an embodiment of the present invention.
Embodiment
The invention discloses a kind of polarisation shift keying modulation demodulation method, send and receive signal and inherit polarization completely
QPSK ripe hardware structure is multiplexed, has the advantages that polarisation shift keying is immunized phase noise, reduction nonlinear fiber and influenceed.
The present invention is described in detail with reference to specification drawings and specific embodiments.
As shown in figure 1, the polarisation shift keying modulation demodulation method that the present invention is provided comprises the following steps：
In transmitting terminal, using QPSK (Quadrature Phase Shift Keying, QPSK) mode, in X
Any QPSK signals are modulated on polarization direction as X polarization signalsOn Y polarization directions, according to input signal S (n)
It is modulated into and X polarization signalsIdentical or opposite Y polarization signalsI.e.：
When S (n)=0
When S (n)=1 (1)
Wherein：
Input signal S (n) represents the binary data to be transmitted (0 or 1), and n is sequence number；
If using another coordinate system xy that 45 degree are tied to form with XY coordinates, having energy corresponding to x or y directions, and it is another
The situation of direction no signal energy.
In receiving terminal, using PDM-QPSK (Polarization Division Multiplexing Quadrature
Phase Shift Keying, palarization multiplexing QPSK) mode will receive signal and (be believed by the first optical signal and the second light
Number composition) be demodulated into corresponding electric signal, then sampled with ADC, quantify after carry out Digital Signal Processing and restore input signal S
(n)。
As shown in Fig. 2 the process of Digital Signal Processing includes successively：Dispersion compensation, clock recovery, adaptive-filtering, phase
Close detection, bit decision and differential decoding.Wherein dispersion compensation, clock recovery, coherent detection, bit decision and differential decoding are adopted
Realized with prior art, adaptive-filtering is realized by linear equalizer using adaptive-filtering coefficient update algorithm, for inclined
Shake demultiplexing and residual chromatic dispersion compensation.
The present invention use improved constant modulus algorithm (CMA, constant modulus algorithm) realize it is adaptive
Filter factor is answered to update.CMA is the most frequently used adaptive-filtering coefficient update algorithm, because training sequence is not needed, and need not
Compensation frequency difference is differed in advance, so being used by main flow commercial system.But for the 2-POLSK signals as shown in formula (1), X is inclined
The signal (the first optical signal) that shakes has correlation with Y polarization signals (the second optical signal), so the coefficient of sef-adapting filter can
Wrong it can restrain, the last output of sef-adapting filter may be：
Wherein,The modulated signal of X polarizations is represented,Represent the modulated signal of Y polarizations. cos(α)、
Sin (α) represents the coefficient that any quadratic sum is equal to 1 with cos (β), sin (β), and α/β is any angle, and j is imaginary unit.ω is
Sending and receiving end light source frequency difference, T is code-element period, and θ is difference.It can be seen that, although the output signal shown in formula (2) and (3) is still
Permanent mould condition is met, but does not polarize X, Y separately.
Therefore the present invention proposes improved CMA algorithms, to X polarized reception signals [Einx] and Y polarized reception signals (n-l)
[Einy(n-l) time domain equalization] is carried out；
It is filtered using equation below：
EoutxAnd Eout (n)y(n) it is respectively the defeated of sef-adapting filter X polarized receptions signal and Y polarized reception signals
Go out, Fxx、Fxy、Fyx、FyyFor four adaptive filter coefficients, n is sequence number, and L is sef-adapting filter series, and l is adaptive
Filter order sequence number；
F is updated using gradient algorithmxx、Fxy、Fyx、FyyValue, converges to the value during minimum value of error ε, ε's determines automatically
Justice is：
εx={ 1-Eoutx(n)[Eoutx(n)]*} (7)
εy={ 1-Eouty(n)[Eouty(n)]*} (8)
εxy={ 2- [Eoutx(n)+jEouty(n)][Eoutx(n)+jEouty(n)]*} (9)
Section 1 and Section 2 in error formula are classical CMA Algorithm Error formulas, and the present invention is added the
Three the characteristics of make use of 2-POLSK, use gradient algorithm to update Fxx、Fxy、Fyx、 FyyIt is worth, coefficient update formula is：
Fxx(l, g+1)=Fxx(l,g)+4μ1εxEoutx(n)[Einx(n-l)]* +4μ2εxy[Eoutx(n)+jEouty(n)]
[Einx(n-l)]* (10)
Fxy(l, g+1)=Fxy(l,g)+4μ1εxEoutx(n)[Einy(n-l)]* +4μ2εxy[Eoutx(n)+jEouty(n)]
[Einy(n-l)]* (11)
Fyx(l, g+1)=Fyx(l,g)+4μ1εyEouty(n)[Einx(n-l)]*- 4 μ2εxyj[Eoutx(n)+jEouty
(n)][Einx(n-l)]* (12)
Fyy(l, g+1)=Fyy(l,g)+4μ1εyEouty(n)[Einy(n-l)]* -4μ2εxyj[Eoutx(n)+jEouty
(n)][Einy(n-l)]* (13)
* it is conjugate of symbol, g represents the g times renewal, μ1According to the small coefficient that needs to use (span can be
1-10-9), j is complex symbol.
After sef-adapting filter is restrained, output will be equal to：
Cos (α), sin (α) represent the coefficient that any quadratic sum is equal to 1, and α is any angle, and j is complex symbol, and j ω t are
Sending and receiving end frequency difference and the product of time, j θXYIt can be random angle angle value.
Multiple correlation computing is done into two outputs, with reference to formula (1), can be obtained
Input signal S (n) can then be recovered.
Formula (16) ± two ambiguous solutions are represented, it can be eliminated by difference encoding and decoding.
There is the present invention polarisation shift keying phase noise is immunized, and resist certain nonlinear effect, and reduce optical fiber non-thread
Property influence advantage, and can the linear damage such as effective compensation dispersion, PMD, the change of automatic compensating polarizing state can be in overlength span
Played a significant role in transmission.Also, send and receive the ripe hardware structure that signal inherits palarization multiplexing QPSK completely, realize letter
It is single, with very strong practicality.
The embodiment of the present invention additionally provides a kind of polarisation shift keying modulation demodulating system, including transmitting terminal and receiving terminal：
The transmitting terminal is provided with modulating unit, and the modulating unit uses QPSK mode, in X polarization directions
On modulate any QPSK signals as X polarization signalsOn Y polarization directions, it is modulated into according to input signal S (n) and X
Polarization signalIdentical or opposite Y polarization signals
When S (n)=0
When S (n)=1
Wherein：
Input signal S (n) represents the binary data to be transmitted, and n is sequence number；
Receiving terminal is provided with demodulating unit and digital signal processing unit, and demodulating unit uses palarization multiplexing QPSK
Receiving signal demodulation is corresponding electric signal, then restores input signal S (n) by digital signal processing unit by mode, is counted
Word signal processing unit is provided with sef-adapting filter, and sef-adapting filter uses the update method of above-mentioned adaptive-filtering coefficient
It is updated.
The present invention is not limited to above-mentioned preferred forms, and anyone should learn that the knot made under the enlightenment of the present invention
Structure changes, and the technical schemes that are same or similar to the present invention are each fallen within protection scope of the present invention.
Claims (5)
1. the update method of receiving terminal adaptive-filtering coefficient, it is characterised in that comprise the following steps：
To X polarized reception signals [Einx] and Y polarized reception signals [Ein (n-l)y(n-l) time domain equalization] is carried out；
It is filtered using equation below：
Wherein：
EoutxAnd Eout (n)y(n) be respectively sef-adapting filter X polarized receptions signal and Y polarized reception signals output, Fxx、
Fxy、Fyx、FyyFor four adaptive filter coefficients, n is sequence number, and L is sef-adapting filter series, and l is sef-adapting filter
Series sequence number；
F is updated using gradient algorithmxx、Fxy、Fyx、FyyValue, converges to the value during minimum value of error ε, ε definition is automatically：
εx={ 1-Eoutx(n)[Eoutx(n)]*}；
εy={ 1-Eouty(n)[Eouty(n)]*}；
εxy={ 2- [Eoutx(n)+jEouty(n)][Eoutx(n)+jEouty(n)]*}；
Corresponding coefficient update formula is：
Fxx(l, g+1)=Fxx(l,g)+4μ1εxEoutx(n)[Einx(n-l)]*
+4μ2εxy[Eoutx(n)+jEouty(n)][Einx(n-l)]*；
Fxy(l, g+1)=Fxy(l,g)+4μ1εxEoutx(n)[Einy(n-l)]*
+4μ2εxy[Eoutx(n)+jEouty(n)][Einy(n-l)]*；
Fyx(l, g+1)=Fyx(l,g)+4μ1εyEouty(n)[Einx(n-l)]*
- 4 μ2εxyj[Eoutx(n)+jEouty(n)][Einx(n-l)]*；
Fyy(l, g+1)=Fyy(l,g)+4μ1εyEouty(n)[Einy(n-l)]*
-4μ2εxyj[Eoutx(n)+jEouty(n)][Einy(n-l)]*；
* it is conjugate of symbol, g represents the g times renewal, μ1According to the small coefficient that needs to use, span can be 1-10-9, j is complex symbol.
2. polarisation shift keying modulation demodulation method, it is characterised in that comprise the following steps：
In transmitting terminal, using QPSK mode, any QPSK signals are modulated on X polarization directions and are polarized as X and are believed
NumberOn Y polarization directions, it is modulated into and X polarization signals according to input signal S (n)Identical or opposite Y polarization letters
Number
When S (n)=0
When S (n)=1
Wherein：
Input signal S (n) represents the binary data to be transmitted, and n is sequence number；
In receiving terminal, use palarization multiplexing QPSK mode by receiving signal demodulation for corresponding electric signal, Ran Houzai
Sampled, quantified with ADC, finally carried out Digital Signal Processing and restore input signal S (n)；
The process of Digital Signal Processing includes successively：Dispersion compensation, clock recovery, adaptive-filtering, coherent detection, bit decision
And differential decoding, wherein adaptive-filtering by linear equalizer using the method as described in claim 1 realize.
3. method as claimed in claim 2, it is characterised in that after sef-adapting filter is restrained, output signal is：
Cos (α), sin (α) represent the coefficient that any quadratic sum is equal to 1, and α is any angle, and j is complex symbol, and j ω t are transmitting-receiving
Hold frequency difference and the product of time, j θXYIt can be random angle angle value.
4. method as claimed in claim 3, it is characterised in that recover input signal S (n) using below equation：
Wherein：± two ambiguous solutions are represented, it can be eliminated by difference encoding and decoding.
5. polarisation shift keying modulation demodulating system, including transmitting terminal and receiving terminal, it is characterised in that：
The transmitting terminal is provided with modulating unit, and the modulating unit uses QPSK mode, is modulated on X polarization directions
Go out any QPSK signals as X polarization signalsOn Y polarization directions, it is modulated into polarize with X according to input signal S (n) and is believed
NumberIdentical or opposite Y polarization signals
When S (n)=0
When S (n)=1
Wherein：
Input signal S (n) represents the binary data to be transmitted, and n is sequence number；
The receiving terminal is provided with demodulating unit and digital signal processing unit, and the demodulating unit uses palarization multiplexing orthogonal phase shift
Receiving signal demodulation is corresponding electric signal, then restores input signal by the digital signal processing unit by keying mode
S (n), the digital signal processing unit is provided with sef-adapting filter, and the sef-adapting filter is used such as claim 1 institute
The method stated carries out the renewal of adaptive-filtering coefficient.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410811063.5A CN104486277B (en) | 2014-12-23 | 2014-12-23 | The update method of modulation-demo-demodulation method, system and adaptive-filtering coefficient |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410811063.5A CN104486277B (en) | 2014-12-23 | 2014-12-23 | The update method of modulation-demo-demodulation method, system and adaptive-filtering coefficient |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN104486277A CN104486277A (en) | 2015-04-01 |
| CN104486277B true CN104486277B (en) | 2017-10-10 |
Family
ID=52760782
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201410811063.5A Active CN104486277B (en) | 2014-12-23 | 2014-12-23 | The update method of modulation-demo-demodulation method, system and adaptive-filtering coefficient |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN104486277B (en) |
Families Citing this family (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107735964B (en) | 2015-06-23 | 2020-01-03 | 华为技术有限公司 | Phase estimation method and device of polarization multiplexing system |
| CN105577289B (en) * | 2015-12-17 | 2018-01-12 | 武汉邮电科学研究院 | Modulating system, method and the modified correlation constant modulus algorithm of phase controlled rotation |
| CN105610507B (en) * | 2015-12-24 | 2018-02-16 | 武汉邮电科学研究院 | A kind of parallel constant modulus algorithm suitable for coherent optical communication system simplifies implementation method |
| CN107769852A (en) * | 2016-08-15 | 2018-03-06 | 深圳清华大学研究院 | Light emitting devices, optical pickup apparatus, radio optical communication system and method |
| CN106789793B (en) * | 2016-12-28 | 2019-07-16 | 武汉邮电科学研究院 | The LMS method without frequency difference difference feedback updated for adaptive equalizer coefficients |
| CN108322262A (en) * | 2017-01-18 | 2018-07-24 | 深圳清华大学研究院 | Radio optical communication system |
| CN107196706B (en) * | 2017-07-18 | 2019-08-27 | 深圳市杰普特光电股份有限公司 | Polarization and phase recovery method |
| CN112039586A (en) * | 2020-08-21 | 2020-12-04 | 武汉邮电科学研究院有限公司 | OSNR measuring method, device and system based on digital signal processing |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102724151A (en) * | 2012-06-15 | 2012-10-10 | 武汉邮电科学研究院 | Communication system, communication method, multichannel adaptive equalizer and OFDM (orthogonal frequency division multiplexing) signal demultiplexing method |
| US8488652B2 (en) * | 2010-03-11 | 2013-07-16 | Nec Laboratories America, Inc. | Systems and methods for blind equalization in a digital receiver |
| EP2709327A2 (en) * | 2012-09-14 | 2014-03-19 | Fujitsu Limited | Updating apparatus and method for equalizer coefficient, receiver and optical communication system |
| CN104168069A (en) * | 2014-08-12 | 2014-11-26 | 武汉邮电科学研究院 | Phase position controlled rotation modulation system and method in coherent light communication field |
-
2014
- 2014-12-23 CN CN201410811063.5A patent/CN104486277B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8488652B2 (en) * | 2010-03-11 | 2013-07-16 | Nec Laboratories America, Inc. | Systems and methods for blind equalization in a digital receiver |
| CN102724151A (en) * | 2012-06-15 | 2012-10-10 | 武汉邮电科学研究院 | Communication system, communication method, multichannel adaptive equalizer and OFDM (orthogonal frequency division multiplexing) signal demultiplexing method |
| EP2709327A2 (en) * | 2012-09-14 | 2014-03-19 | Fujitsu Limited | Updating apparatus and method for equalizer coefficient, receiver and optical communication system |
| CN104168069A (en) * | 2014-08-12 | 2014-11-26 | 武汉邮电科学研究院 | Phase position controlled rotation modulation system and method in coherent light communication field |
Non-Patent Citations (2)
| Title |
|---|
| 偏振复用差分相移键控信号的数字相干解调与偏振解复用算法研究;冯勇、闻和、张汉一;《光学学报》;20100531;第30卷(第5期);全文 * |
| 邸雪静、童程、张霞、张晓光、席丽霞.高速相干光通信系统中的自适应步长恒模算法.《光学学报》.2012,第32卷(第10期),全文. * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN104486277A (en) | 2015-04-01 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN104486277B (en) | The update method of modulation-demo-demodulation method, system and adaptive-filtering coefficient | |
| Kikuchi | Fundamentals of coherent optical fiber communications | |
| Kikuchi | Digital coherent optical communication systems: Fundamentals and future prospects | |
| Kikuchi et al. | Multi-level signaling in the Stokes space and its application to large-capacity optical communications | |
| KR101574986B1 (en) | Nonlinear cross-polarization mitigation algorithm | |
| CN105281862B (en) | A kind of direct detecting system of palarization multiplexing and method | |
| US20110194855A1 (en) | Superimposed training and digital filtering coherent optical receivers | |
| CN104168069B (en) | The modulating system of phase controlled rotation in the coherent light communications field and modulator approach | |
| US20130315607A1 (en) | Low cost direct modulation and coherent detection optical ofdm | |
| US20200007263A1 (en) | Methods and apparatus for dual polarisation optical communication | |
| US9106503B1 (en) | Method and apparatus for recovering time-domain hybrid modulated QAM signals | |
| Lu et al. | Joint carrier phase and frequency-offset estimation with parallel implementation for dual-polarization coherent receiver | |
| CN110535532A (en) | It is a kind of to polarize unrelated pulse amplitude modulated signal coherent reception method and system | |
| US9692521B1 (en) | Polarization pre-compensation technique for polarization-division-multiplexed direct-detection optical communication systems | |
| CN106301593B (en) | Adaptive blind polarization demultiplexing treating method and apparatus | |
| Yang et al. | Fiber‐wireless integration for 80 Gbps polarization division multiplexing− 16QAM signal transmission at W‐band without RF down conversion | |
| US20140003824A1 (en) | Equalization mechanism for processing traffic based on three-quadrature amplitude modulation (3qam) | |
| Ishimura et al. | Multi-dimensional permutation modulation aiming at both high spectral efficiency and high power efficiency | |
| CN110460441B (en) | Continuous variable quantum key distribution method and system based on orbital angular momentum | |
| US20090310966A1 (en) | Direct detection receiver using cross-polarization interferometer for polmux-ask system | |
| Zhang et al. | Cost-effective and hardware-efficient coherent scheme for 400g short-reach transmission | |
| CN105577289B (en) | Modulating system, method and the modified correlation constant modulus algorithm of phase controlled rotation | |
| RU2664019C9 (en) | Device and method for adaptive compensation of distortion and restoration of carrier signal for coherent receivers | |
| Wang et al. | Real-time stealth optical transmission via dither-remodulation in a bias controller of a Mach-Zehnder modulator | |
| Ranzini et al. | Optoelectronic signal processing for chromatic dispersion mitigation in direct detection systems |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| CP01 | Change in the name or title of a patent holder | ||
| CP01 | Change in the name or title of a patent holder |
Address after: 430074, No. 88, postal academy road, Hongshan District, Hubei, Wuhan Patentee after: Wuhan post and Telecommunications Science Research Institute Co., Ltd. Address before: 430074, No. 88, postal academy road, Hongshan District, Hubei, Wuhan Patentee before: Wuhan Inst. of Post & Telecom Science |