CN106452594A - Improved polarization mode dispersion compensation method based on radius oriented equalizer - Google Patents
Improved polarization mode dispersion compensation method based on radius oriented equalizer Download PDFInfo
- Publication number
- CN106452594A CN106452594A CN201611056646.7A CN201611056646A CN106452594A CN 106452594 A CN106452594 A CN 106452594A CN 201611056646 A CN201611056646 A CN 201611056646A CN 106452594 A CN106452594 A CN 106452594A
- Authority
- CN
- China
- Prior art keywords
- tap coefficient
- coefficient values
- values vector
- initial tap
- vector
- 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
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
- H04B10/25—Arrangements specific to fibre transmission
- H04B10/2507—Arrangements specific to fibre transmission for the reduction or elimination of distortion or dispersion
- H04B10/2569—Arrangements specific to fibre transmission for the reduction or elimination of distortion or dispersion due to polarisation mode dispersion [PMD]
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L27/00—Modulated-carrier systems
- H04L27/01—Equalisers
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Optical Communication System (AREA)
- Digital Transmission Methods That Use Modulated Carrier Waves (AREA)
Abstract
The invention provides an improved polarization mode dispersion compensation method based on a radius oriented equalizer, and relates to coherent optical fiber communication technology. The method comprises the following steps: S1, dividing a 16QAM standard constellation diagram into three circles, calculating decision thresholds th1 and th2, wherein th1 = R1 + (1 - r) R2/2, th2 = R3 + (1 + R) R2/2, the squared values of the radiuses of the three circles are separately R1, R2 and R3, and r is not smaller than 0.06 and is not greater than 0.5; S2, setting an input signal vector of the radius oriented equalizer as Y (n), setting a tap coefficient vector as W (n), avd calculating an output signal Z (n); S3, calculating an error function according to different circles where | Z (n) | 2 is located; and S3, calculating the tap coefficient vector of every update according to the error function; and substituting the tap coefficient vector of every update in S2, and achieving polarization mode dispersion continuous compensation on the output signal Z (n) for different n value increases. By adoption of the improved polarization mode dispersion compensation method provided by the invention, the compensation effect can be improved.
Description
Technical field
The present invention relates to coherent fiber communication technical field, is specifically related to a kind of improved based on radius guiding equalizer
Polarization Mode Dispersion Compensation.
Background technology
In high speed coherent fiber communication system, in order to improve transmission capacity and transmission range, need to add in receiving terminal
Digital Signal Processing (DSP, Digital Signal Processing) algorithm, the various damages for coming in compensated optical fiber.Wherein,
For optical fiber in the compensation of polarization mode dispersion, time-domain equalizer is typically adopted, equal come control break by calculating error function
The tap coefficient of weighing apparatus, so as to realize to signal polarization mode chromatic dispersion compensation, error function is less, and compensation effect is better.
Polarization mode dispersion (PMD) compensation algorithm typically adopts transverse mode algorithm (CMA, Constant Modulus Algorithm), but
For higher order modulation formats, such as 16 rank quadrature amplitudes (16QAM, 16-aryquadrature amplitude modulation),
With multiple modulus value, if directly adopting CMA algorithm, error function can be made to be not zero.In order to carry out polarization mode to 16QAM signal
Dispersion compensation, it is thus proposed that actionradius are oriented to equalizer, i.e., first carry out judging a point circle to signal, the signals of different circles with not
It is compared with modulus value, so as to obtain error function, the error function for so obtaining theoretically is attributed to null value.
But actionradius are oriented to equalizer when there is polarization mode dispersion, amplitude is judged to be possible to erroneous judgement occur,
A point circle mistake is caused, so as to cause error function to be not zero, compensation effect is inadequate.
Content of the invention
For defect present in prior art, it is an object of the invention to provide a kind of improved equal based on radius guiding
The Polarization Mode Dispersion Compensation of weighing apparatus, carries out polarization mode dispersion (PMD) compensation to 16QAM signal, and error function is carried close to null value
High compensation effect.
For reaching object above, the present invention takes a kind of improved polarization mode dispersion (PMD) compensation for being oriented to equalizer based on radius
Method, including step：
S1. 16QAM standard planisphere is divided into three circles, calculates point two decision threshold th1 of circle and th2, a th1=[R1+
(1-r) R2]/2, th2=[R3+ (1+r) R2]/2, wherein, the radius squared value of three circles is respectively R1, R2 and R3, and r is control
The parameter of area size, 0.06≤r≤0.5 shared by mesosphere processed；
S2. set radius be oriented to equalizer input signal vector be Y (n), tap coefficient vector be W (n), output signal Z
N ()=conv { Y (n), W (n) }, wherein, conv represents convolution algorithm, and n is the integer more than or equal to 0；
S3. calculation error function e (n), if | Z (n) |2≤ th1, then error function e (n)=| Z (n) |2- R1；If th1<|
Z(n)|2<Th2, then error function e (n)=| Z (n) |2- R2；If | Z (n) |2>=th2, then error function e (n)=| Z (n)
|2- R3；
S4. using gradient descent method, tap coefficient vector, W (n+1)=W (n)-μ Y* (n) z are updated according to error function
N () e (n), wherein, W (n+1) is the tap coefficient vector for updating each time, and μ is conjugation of iteration step length, the Y* (n) for y (n)；
Tap coefficient vector after updating every time is brought into S2, different n values is increased, realizes the polarization mode color of output signal Z (n)
Scattered Continuous Compensation.
On the basis of technique scheme, in the S1, the difference according to 16QAM complex signal amplitude divides circle, and r takes
Value is relevant with signal to noise ratio, and the value of r is improved with the increase of noise.
On the basis of technique scheme, in the S2, during n=0, radius is oriented to the original input signal amount of equalizer
For Y (0), initial tap coefficient values vector is that the length of W (0), W (0) is equal to tap number, then radius is oriented to the initially defeated of equalizer
Go out signal Z (0)=conv { Y (0), W (0) }.
On the basis of technique scheme, the error function of Initial output signal is calculated, if | Z (0) |2≤ th1, then miss
Difference function e (0)=| Z (0) |2- R1；If th1<|Z(0)|2<Th2, then error function e (0)=| Z (0) |2- R2；If | Z (0)
|2>=th2, then error function e (0)=| Z (0) |2- R3.
On the basis of technique scheme, after the error function of Initial output signal draws, in the S3, using gradient
Descent method, renewal tap coefficient, W (0+1)=W (0)-μ Y* (0) z (0) e (0), wherein, it is Y (0) that μ is iteration step length, Y* (0)
Conjugation；S2 is proceeded to again, and when calculating n=1, radius is oriented to the output signal of equalizer.
On the basis of technique scheme, parameter r=0.1, μ=6 × 10^ (- 6).
The beneficial effects of the present invention is：A point circle threshold value is redefined, polarization mode color is carried out to 16QAM signal
When dissipating compensation, under different state of signal-to-noise, when r takes 0.06 to 0.5, the bit error rate (BER, Bit Error Rate) compares
Little, radius is oriented to the better performances of equalizer, is oriented to equalizer algorithm with respect to traditional radius, and error function of the present invention is close to
In null value, compensation effect is improve.
Description of the drawings
Fig. 1 is point circle schematic diagram of 16QAM standard planisphere in prior art；
Fig. 2 is point circle schematic diagram of embodiment of the present invention 16QAM standard planisphere；
When Fig. 3 carries out polarization mode dispersion (PMD) compensation for the embodiment of the present invention to 16QAM signal, under different state of signal-to-noise, r
The relation schematic diagram of value and the bit error rate.
Specific embodiment
Below in conjunction with drawings and Examples, the present invention is described in further detail.
Polarization Mode Dispersion Compensation of the present invention based on radius guider, specifically includes step：
S1. according to the difference of 16QAM complex signal amplitude, 16QAM standard planisphere is divided into three circles, i.e. inner ring, centre
Circle and outer ring, calculate point two decision threshold th1 of circle and a th2.If the radius squared value of tri- circles of 16QAM is respectively R1, R2
And R3, then th1=[R1+ (1-r) R2]/2, th2=[R3+ (1+r) R2]/2, wherein, r region shared by control mesosphere is big
Little parameter, the value of r is relevant with signal to noise ratio, and when noise is larger, the value of r should be improved, and r is 0.06≤r in span
≤0.5.As shown in figure 1, for point circle schematic diagram of 16QAM standard planisphere in prior art, d1For between threshold value th1 and th2
Distance；As shown in Fig. 2 for point circle schematic diagram of embodiment 16QAM standard planisphere, d2For between threshold value th1 and th2 away from
From；Span according to r in the present embodiment, it is seen that d2More than d1.
S2. set radius be oriented to equalizer input signal vector be Y (n), tap coefficient vector be W (n), output signal Z
N ()=conv { Y (n), W (n) }, wherein, conv represents convolution algorithm, and n is the integer more than or equal to 0, n=0,1,2 ... n.
S3. the calculating of error function e (n)：If | Z (n) |2≤ th1, then error function e (n)=| Z (n) |2- R1；If th1
<|Z(n)|2<Th2, then error function e (n)=| Z (n) |2- R2；If | Z (n) |2>=th2, then error function e (n)=| Z (n)
|2- R3.
S4. using gradient descent method, tap coefficient vector is updated according to error function：W (n+1)=W (n)-μ Y* (n) z
N () e (n), wherein, W (n+1) is the tap coefficient vector for updating each time, and μ is conjugation of iteration step length, the Y* (n) for Y (n).
Tap coefficient vector after updating each time is brought into step S2, different n values is increased, realizes the inclined of output signal Z (n)
Polarization mode dispersion Continuous Compensation.
In above-mentioned steps, in more detail, n=0 when initial, in step S2, radius is oriented to the original input signal of equalizer
Measure as Y (0), initial tap coefficient values vector is typically set to [00 ... 010 ... 00] for W (0), W (0), the length of W (0) is equal to tap
Number, then the Initial output signal that radius is oriented to equalizer is Z (0)=conv { Y (0), W (0) }, and wherein Z (0) is initial output
Signal.
Then the error function e (0) of Initial output signal, in step S3, is calculated, if | Z (0) |2≤ th1, then error function
E (0)=| Z (0) |2- R1；If th1<|Z(0)|2<Th2, then error function e (0)=| Z (0) |2- R2；If | Z (0) |2≥
Th2, then error function e (0)=| Z (0) |2- R3.
In step S4, according to the error function e (0) of the Initial output signal for obtaining, using gradient descent method, tap is updated
Coefficient, W (0+1)=W (0)-μ Y* (0) z (0) e (0), i.e.,：W (1)=W (0)-μ Y* (0) z (0) e (0).Wherein, μ is iteration step
Long, Y* (0) is the conjugation of Y (0).
Then, step S2 is proceeded to, then when n=1 is calculated, radius is oriented to the output signal of equalizer, and then obtains error letter
Number e (1), preferred parameter r=0.1, μ=6 × 10^ (- 6)；Tap coefficient being updated further according to gradient descent method, proceeds to again
S2, calculates n=2, and until calculating to n-th output signal, in this process, polarization mode dispersion is continuously mended
Repay.
In PMD (Polarization Mode Dispersion, polarization mode dispersion) phantom, the baud rate of signal
For 32GBaud/s, it is considered to worst case, if signal state of polarization is 45 degree with the angle of principal state of polarization (psp), the group of two principal state of polarization (psp)
Time delay is 10 psecs.The total length of data takes 2^19, and removes 10000 not converged data points of beginning, then calculates BER
(Bit Error Rate, the bit error rate).
As shown in figure 3, for 16QAM signal under these conditions, using polarization mode color of the present invention based on radius guider
During scattered compensation method, in the case of different SNR (signal to noise ratio), the value of r and the curve linear relationship of BER.Wherein r=0 is existing skill
In art, radius is oriented to the polarization mode dispersion (PMD) compensation algorithm of equalizer, and as seen from Figure 3, during r=0, BER is larger, and radius is oriented to
Equalizer performance is bad, and when r takes the present invention 0.06 to 0.5, BER is less, and it is preferable that radius is oriented to equalizer performance.
The present invention is not limited to above-mentioned embodiment, for those skilled in the art, without departing from
On the premise of the principle of the invention, some improvements and modifications can also be made, these improvements and modifications are also considered as the protection of the present invention
Within the scope of.The content not being described in detail in this specification belongs to prior art known to professional and technical personnel in the field.
Claims (6)
1. a kind of improved based on radius be oriented to equalizer Polarization Mode Dispersion Compensation, it is characterised in that including step：
S1. 16QAM standard planisphere is divided into three circles, calculates point two decision threshold th1 of circle and th2, a th1=[R1+ (1-
R) R2]/2, th2=[R3+ (1+r) R2]/2, wherein, the radius squared value of three circles is respectively R1, R2 and R3, and r is in control
Between the shared area size of circle parameter, 0.06≤r≤0.5；
S2. set radius be oriented to equalizer input signal vector be Y (n), tap coefficient vector be W (n), output signal Z (n)=
Conv { Y (n), W (n) }, wherein, conv represents convolution algorithm, and n is the integer more than or equal to 0；
S3. calculation error function e (n), if | Z (n) |2≤ th1, then error function e (n)=| Z (n) |2- R1；If th1<|Z(n)
|2<Th2, then error function e (n)=| Z (n) |2- R2；If | Z (n) |2>=th2, then error function e (n)=| Z (n) |2- R3；
S4. using gradient descent method, tap coefficient vector, W (n+1)=W (n)-μ Y are updated according to error function*(n)z(n)e
N (), wherein, W (n+1) is the tap coefficient vector for updating each time, and μ is iteration step length, Y*N () is the conjugation of Y (n)；Will be per
Tap coefficient vector after secondary renewal brings S2 into, increases for different n values, realizes the polarization mode dispersion of output signal Z (n) even
Continuous compensation.
2. as claimed in claim 1 improved based on radius be oriented to equalizer Polarization Mode Dispersion Compensation, it is characterised in that：
In the S1, the difference according to 16QAM complex signal amplitude divides circle, and the value of r is relevant with signal to noise ratio, and the value of r is with noise
Increase and improve.
3. as claimed in claim 1 improved based on radius be oriented to equalizer Polarization Mode Dispersion Compensation, it is characterised in that：
In described S2, when n=0, it is Y (0) that radius is oriented to the original input signal amount of equalizer, and initial tap coefficient values vector is W (0), W, and initial tap coefficient values vector is W (0), W, and initial tap coefficient values vector is W (0), W, and initial tap coefficient values vector is W (0), W, and initial tap coefficient values vector is W (0), W, and initial tap coefficient values vector is W (0), W, and initial tap coefficient values vector is W (0), W, and initial tap coefficient values vector is W (0), W, and initial tap coefficient values vector is W (0), W, and initial tap coefficient values vector is W (0), W, and initial tap coefficient values vector is W (0), W, and initial tap coefficient values vector is W (0), W, and initial tap coefficient values vector is W (0), W, and initial tap coefficient values vector is W (0), W, and initial tap coefficient values vector is W (0), W, and initial tap coefficient values vector is W (0), W, and initial tap coefficient values vector is W (0), W, and initial tap coefficient values vector is W (0), W, and initial tap coefficient values vector is W (0), W, and initial tap coefficient values vector is W (0), W, and initial tap coefficient values vector is W (0), W, and initial tap coefficient values vector is W (0), W, and initial tap coefficient values vector is W (0), W, and initial tap coefficient values vector is W (0), W, and initial tap coefficient values vector is W (0), W, and initial tap coefficient values vector is W (0), W, and initial tap coefficient values vector is W (0), W, and initial tap coefficient values vector is W (0), W, and initial tap coefficient values vector is W (0), W, and initial tap coefficient values vector is W (0), W, and initial tap coefficient values vector is W (0), W, and initial tap coefficient values vector is W (0), W, and initial tap coefficient values vector is W (0), W, and initial tap coefficient values vector is W (0), W, and initial tap coefficient values vector is W (0), W, and initial tap coefficient values vector is W (0), W, and initial tap coefficient values vector is W (0), W, and initial tap coefficient values vector is W (0), W, and initial tap coefficient values vector is W (0), W, and initial tap coefficient values vector is W (0), W, and initial tap coefficient values vector is W (0), W, and initial tap coefficient values vector is W (0), W, and initial tap coefficient values vector is W (0), W, and initial tap coefficient values vector is W (
(0) length is equal to tap number, then radius is oriented to Initial output signal Z (the 0)=conv { Y (0), W (0) } of equalizer.
4. as claimed in claim 3 improved based on radius be oriented to equalizer Polarization Mode Dispersion Compensation, it is characterised in that：
The error function of Initial output signal is calculated, if | Z (0) |2≤ th1, then error function e (0)=| Z (0) |2- R1；If th1<|Z
(0)|2<Th2, then error function e (0)=| Z (0) |2- R2；If | Z (0) |2>=th2, then error function e (0)=| Z (0) |2-
R3.
5. as claimed in claim 4 improved based on radius be oriented to equalizer Polarization Mode Dispersion Compensation, it is characterised in that：
After the error function of Initial output signal draws, in the S3, using gradient descent method, tap coefficient, W (0+1)=W is updated
(0)-μY*(0) z (0) e (0), wherein, μ is iteration step length, Y*(0) it is the conjugation of Y (0)；S2 is proceeded to again, when calculating n=1, radius
It is oriented to the output signal of equalizer.
6. as described in arbitrary in claim 1 to 5 improved based on radius be oriented to equalizer Polarization Mode Dispersion Compensation, its
It is characterised by：Parameter r=0.1, μ=6 × 10^ (- 6).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201611056646.7A CN106452594B (en) | 2016-11-25 | 2016-11-25 | A kind of improved Polarization Mode Dispersion Compensation that balanced device is oriented to based on radius |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201611056646.7A CN106452594B (en) | 2016-11-25 | 2016-11-25 | A kind of improved Polarization Mode Dispersion Compensation that balanced device is oriented to based on radius |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN106452594A true CN106452594A (en) | 2017-02-22 |
| CN106452594B CN106452594B (en) | 2018-10-09 |
Family
ID=58218491
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201611056646.7A Active CN106452594B (en) | 2016-11-25 | 2016-11-25 | A kind of improved Polarization Mode Dispersion Compensation that balanced device is oriented to based on radius |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN106452594B (en) |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8234549B2 (en) * | 2008-03-06 | 2012-07-31 | Nec Laboratories America, Inc. | Simultaneous PMD compensation and chromatic dispersion compensation using LDPC coded OFDM |
| US8320778B2 (en) * | 2009-09-03 | 2012-11-27 | At&T Intellectual Property I, L.P. | Blind equalization algorithms for adaptive polarization recovery and PMD compensation |
| CN103684600A (en) * | 2012-09-14 | 2014-03-26 | 富士通株式会社 | Updating device and method for equalizer coefficients, receiver and optical communication system |
| CN104429034A (en) * | 2013-06-08 | 2015-03-18 | 华为技术有限公司 | Data receiving and sending method, device and system |
| CN105680946A (en) * | 2016-01-22 | 2016-06-15 | 武汉邮电科学研究院 | Adaptive digital signal processing algorithm for compensating optical fiber transmission nonlinear damages |
| CN105703838A (en) * | 2016-01-26 | 2016-06-22 | 哈尔滨工业大学深圳研究生院 | A coherent light receiver dynamic balancing method based on a butterfly linear Kalman filter |
| CN106130643A (en) * | 2016-06-24 | 2016-11-16 | 温州大学 | A kind of high speed optical communication system electrical dispersion compensation method |
-
2016
- 2016-11-25 CN CN201611056646.7A patent/CN106452594B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8234549B2 (en) * | 2008-03-06 | 2012-07-31 | Nec Laboratories America, Inc. | Simultaneous PMD compensation and chromatic dispersion compensation using LDPC coded OFDM |
| US8320778B2 (en) * | 2009-09-03 | 2012-11-27 | At&T Intellectual Property I, L.P. | Blind equalization algorithms for adaptive polarization recovery and PMD compensation |
| CN103684600A (en) * | 2012-09-14 | 2014-03-26 | 富士通株式会社 | Updating device and method for equalizer coefficients, receiver and optical communication system |
| CN104429034A (en) * | 2013-06-08 | 2015-03-18 | 华为技术有限公司 | Data receiving and sending method, device and system |
| CN105680946A (en) * | 2016-01-22 | 2016-06-15 | 武汉邮电科学研究院 | Adaptive digital signal processing algorithm for compensating optical fiber transmission nonlinear damages |
| CN105703838A (en) * | 2016-01-26 | 2016-06-22 | 哈尔滨工业大学深圳研究生院 | A coherent light receiver dynamic balancing method based on a butterfly linear Kalman filter |
| CN106130643A (en) * | 2016-06-24 | 2016-11-16 | 温州大学 | A kind of high speed optical communication system electrical dispersion compensation method |
Also Published As
| Publication number | Publication date |
|---|---|
| CN106452594B (en) | 2018-10-09 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN107579780B (en) | Parameter self-adaptive polarization state tracking and balancing method based on radius-oriented Kalman | |
| US11962344B2 (en) | Method and apparatus for obtaining transmitter test parameter, and storage medium | |
| CN102511136B (en) | Dispersion estimator and method for estimating dispersion | |
| US8208807B2 (en) | Transmission of eye information from opto-electronic modules | |
| CN105680946A (en) | Adaptive digital signal processing algorithm for compensating optical fiber transmission nonlinear damages | |
| US8902959B2 (en) | System and method for determining channel loss in a dispersive communication channel at the Nyquist frequency | |
| CN110061761A (en) | Signal equalizing method and device, photoreceiver | |
| WO2021159860A1 (en) | Testing device, testing method and processor | |
| CN111404634B (en) | Large-scale MIMO detection method, system and application based on variable step length iteration | |
| CN103763037B (en) | Dynamic compensation receiver and dynamic compensation receiving method | |
| CN106452594A (en) | Improved polarization mode dispersion compensation method based on radius oriented equalizer | |
| Kamalian et al. | Spectral efficiency estimation in periodic nonlinear Fourier transform based communication systems | |
| CN111988249B (en) | Receiving end equalization method based on adaptive neural network and receiving end | |
| CN105991186B (en) | Monitoring device, method and the receiver of optical signal to noise ratio | |
| CN111884960A (en) | Polarization demultiplexing signal processing blind equalization method and polarization demultiplexing device | |
| WO2023159886A1 (en) | Probabilistic-shaping qam dynamic equalization method and probabilistic-shaping qam digital signal processing method | |
| CN113141196B (en) | Channel compensation method and communication device | |
| CN113285762B (en) | Modulation format identification method based on relative entropy calculation | |
| US20160365922A1 (en) | Decision threshold adjustment | |
| CN105490975B (en) | Part decision threshold setting method of the mimo wireless communication based on signal-to-noise ratio (SNR) estimation | |
| KR101223812B1 (en) | Method and device for allocating bit in optical network system | |
| Chen et al. | On the impact of probabilistic shaping rates to the decision-based phase noise mitigation | |
| CN115378507B (en) | Noise equalization method and device suitable for multi-eigenvalue nonlinear frequency division multiplexing system | |
| CN114629556B (en) | Low-complexity optimal power distribution method | |
| KR101361356B1 (en) | Method and system for calculation secrecy capacity using relative distance variable in wireless network with secure zone |
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 |