CN115102623B - Dense optical fiber coding method based on optical frequency comb and optical fiber grating - Google Patents
Dense optical fiber coding method based on optical frequency comb and optical fiber grating Download PDFInfo
- Publication number
- CN115102623B CN115102623B CN202210726315.9A CN202210726315A CN115102623B CN 115102623 B CN115102623 B CN 115102623B CN 202210726315 A CN202210726315 A CN 202210726315A CN 115102623 B CN115102623 B CN 115102623B
- Authority
- CN
- China
- Prior art keywords
- optical
- wavelength
- different
- comb
- frequency comb
- 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
- 230000003287 optical effect Effects 0.000 title claims abstract description 129
- 239000013307 optical fiber Substances 0.000 title claims abstract description 37
- 238000000034 method Methods 0.000 title claims abstract description 19
- 239000000835 fiber Substances 0.000 claims description 23
- 238000003491 array Methods 0.000 claims description 3
- 238000001228 spectrum Methods 0.000 description 9
- 210000001520 comb Anatomy 0.000 description 6
- 238000010586 diagram Methods 0.000 description 5
- 238000012544 monitoring process Methods 0.000 description 3
- 244000126211 Hericium coralloides Species 0.000 description 2
- 238000002310 reflectometry Methods 0.000 description 2
- 230000003595 spectral effect Effects 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
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
- H04B10/501—Structural aspects
- H04B10/506—Multiwavelength transmitters
-
- 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]
- H04B10/5563—Digital frequency modulation
-
- 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
- H04B10/572—Wavelength control
Landscapes
- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Optical Modulation, Optical Deflection, Nonlinear Optics, Optical Demodulation, Optical Logic Elements (AREA)
- Optical Communication System (AREA)
Abstract
The invention discloses an intensive optical fiber coding method based on an optical frequency comb and an optical fiber grating, which comprises the following steps: c wave band pulse signals are emitted by the light source module, and the signals comprise more than m optical pulses with different central wavelengths and overlapping in time domain; dividing pulse light into m different adjustable frequency comb sources by utilizing an optical divider, wherein each adjustable frequency comb source generates comb teeth on an optical pulse wavelength domain at fixed intervals, and the optical comb intervals generated by the different optical frequency comb sources are different; each optical frequency comb source is connected with a (m-1) 2 port wavelength encoder, and the wavelength combinations contained in the optical pulses leaving different ports of the same encoder are different; taking different optical comb intervals as a first code, taking different combinations of wavelength components as a second code for each code word, and forming a set of all codes by the final results of the two codes; the method solves the problems that the real-time coding scale of the prior art is still limited and the use requirement of a large-scale network cannot be met.
Description
Technical Field
The invention belongs to the technical field of network digitization, and particularly relates to an intensive optical fiber coding method based on an optical frequency comb and an optical fiber grating.
Background
Optical fiber coding is the basic and core technology for realizing all-optical network digitization. The optical fiber link safety is the basis for ensuring the optical access network safety, and researches show that about one third of the optical network faults are caused by the optical fiber cable faults, so that each optical fiber link in the optical access network is digitally encoded, and the network state is monitored by utilizing the encoding, so that the more accurate, reliable, intelligent and efficient all-optical network digital management is the premise that the optical access network can operate efficiently and stably. The efficiency of optical fiber coding directly influences the effect of the digital realization of the all-optical network.
Most of the currently used optical fiber coding techniques only use fiber gratings to perform one-dimensional or two-dimensional wavelength coding on monitoring light pulses. The one-dimensional code wavelength code can only distribute a single wavelength as a unique label for one link, has the advantages of simple structure and convenient realization, the encoder only comprises one fiber grating arranged at the user end, and the defect is obvious that the used spectrum resource linearly grows along with the number of the code links, and can only meet the code requirement of a small-scale optical network. The two-dimensional wavelength coding uses an optical encoder consisting of a fiber grating and a one-to-two optical splitter, the encoder is arranged at a local side in an access network, the complexity of a user side is reduced by adopting centralized coding, the coding efficiency is greatly improved compared with one-dimensional coding, but the coding efficiency is limited by spectrum resources in practical use and still only can realize the coding of hundreds of links.
The method for increasing the number of codes is mainly multiplexing in time domain, dividing a plurality of users into a group, adopting a polling mode, only coding the optical fiber links of a certain group of users in a period of time, and effectively coding each optical fiber link by setting a proper polling period. The effective coding quantity increase can be realized by simply using an optical switching and control circuit in combination with the time division multiplexing wavelength coding method, but when the monitoring link is longer, the polling window allocated to each group of users also needs to be correspondingly increased, and in addition, the increase of the quantity of users also needs to poll more groups to meet the demands, so that the polling period is inevitably prolonged, the time for the users to be not identified and managed is increased, and the response efficiency of fault monitoring is reduced.
The targeted coding technology cannot be suitable for realizing real-time coding of a large-scale and high-reliability all-optical network.
Disclosure of Invention
The invention aims to solve the technical problems that: the dense optical fiber coding method based on the optical frequency comb and the optical fiber grating is provided to solve the technical problems that the real-time coding scale in the prior art is still limited, the use requirement of a large-scale network cannot be met, and the like.
The technical scheme of the invention is as follows:
a compact fiber coding method based on optical frequency combs and fiber gratings, the method comprising:
Step 1, a C-band pulse signal is emitted by a light source module, wherein the signal comprises more than m optical pulses with different central wavelengths and overlapped in a time domain;
step 2, uniformly dividing pulse light to n different adjustable frequency comb sources by utilizing an optical divider, wherein each adjustable frequency comb source generates comb teeth on an optical pulse wavelength domain at fixed intervals, and the optical comb intervals generated by different optical frequency comb sources are different;
Step 3, each optical frequency comb source is connected with a2 (m-1) -port wavelength encoder, and the wavelength combinations contained in the optical pulses leaving different ports of the same encoder are different;
And 4, taking different optical comb intervals as a first code, and taking different combinations of wavelength components as a second code for each code word, wherein the final results of the two codes form a set of all codes.
The light source is controlled by external signals, and m laser arrays generate m laser arrays with the same width, power and period in the time domain; the optical pulses with different central wavelengths and the same 3dB bandwidth in the wavelength domain, the interval between the central wavelengths of adjacent optical pulses is larger than the bandwidth of the adjacent optical pulses so as to ensure that the pulses are not aliased in the wavelength domain, and the pulses leave the laser at the same time and are combined into one pulse in the time domain through a coupler built in the light source module.
When the optical frequency comb source works in the wavelength range used by the light source, the generated frequency combs are equal in interval and smaller than the interval of the central wavelengths of adjacent optical pulses, and the interval of the central wavelengths of the pulses can divide the interval of the frequency combs.
N different codes are generated by a tunable optical frequency comb source of n different comb teeth.
The encoder is formed by connecting 2 (m-1) -1 optical splitters in a one-to-two mode step by step, two output ports of the upper optical splitter are respectively connected with input ports of the lower optical splitter, and only one port is selected from two output ports of one optical splitter to place an optical fiber grating.
Each fiber grating totally reflects one of the wavelengths generated by the light source and transmits the other wavelengths, and the fiber gratings used in each stage have the same parameter index; each port of the encoder holds pulses of at least one wavelength.
A total of 2 (m-1) wavelength codes can be achieved using m wavelengths of light.
The use of an optical frequency comb containing m wavelength optical pulses and n spacing results in a total of n x 2 (m-1) codes, each code uniquely corresponding to one fiber optic link.
The invention has the beneficial effects that:
The invention takes the multi-wavelength search light pulse synchronously output by the multi-wavelength pulse light source as the carrier of coding information, and codes the pulse wavelength twice by the adjustable light frequency comb source and the fiber bragg grating, thus realizing coding for a large number of users under the condition of using limited wavelength resources. The light source module emits a C-band pulse signal, the signal comprises a plurality of optical pulses with different central wavelengths and overlapped in time domain, the optical pulses are evenly distributed to a plurality of adjustable frequency comb sources through a splitter, the optical frequency comb sources generate frequency combs on the optical pulses at different intervals, the light leaving each optical frequency comb source then enters a fiber grating encoder, a cascade grating positioned in the optical frequency comb sources selectively reflects pulse wavelengths, unique pulse wavelength combinations are formed at output ports, the subsequent encoders of all the optical frequency comb sources have the same structure, the output ports of the encoders are connected to all optical fiber links in a descending way, and for a certain link, the combination type of the wavelength of the optical pulses in the wavelength domain and the number of teeth contained in each wavelength jointly form unique coded information of the optical pulse.
The invention utilizes fewer wavelength resources to complete encoding of more links, saves spectrum resources, and can greatly improve the scale of the network which can be monitored by the all-optical network digitizing technology when the optical fiber channels are tense and the number of users is gradually increased.
The invention combines the fiber grating coding technology and the optical frequency comb coding method to improve the number of fiber links capable of being coded simultaneously, and solves the problems that the real-time coding scale of the prior art is still limited and the use requirement of a large-scale network cannot be met.
Drawings
FIG. 1 is a diagram of a device through which coded light pulses pass from generation to entry into an optical fiber link;
FIG. 2 is a spectrum of an optical pulse output by a multi-wavelength laser;
FIG. 3 is a spectral diagram of an optical pulse after passing through a tunable optical frequency comb source;
FIG. 4 is a block diagram of a fiber grating encoder;
FIG. 5 is a graph of the spectrum of the light pulse after passing through the fiber grating encoder.
Detailed Description
In order to increase the number of simultaneously encodable fiber links, the invention proposes the following encoding method: the compact optical fiber coding method based on the optical frequency comb and the optical fiber grating comprises the following steps (see figure 1):
Step 1, a light source module emits a C-band pulse signal, wherein the signal comprises m optical pulses with different center wavelengths and overlapping in a time domain;
The multi-wavelength pulse light source can be controlled by external signals, and m lasers with different central wavelengths generate m lasers with the same width, power and period in the time domain; the optical pulses with different central wavelengths and the same 3dB bandwidth in the wavelength domain, the interval between the central wavelengths of adjacent optical pulses is larger than the optical pulse width so as to ensure that the pulses are not aliased in the wavelength domain, and the pulses leave the laser at the same time and are combined into one pulse in the time domain through a coupler built in the light source module.
Step 2, uniformly dividing pulse light to a plurality of different adjustable frequency comb sources by utilizing an optical divider, wherein each adjustable frequency comb source generates comb teeth on an optical pulse wavelength domain at fixed intervals, and the optical comb intervals generated by the different optical frequency comb sources are different;
And 3, connecting an m-port wavelength encoder behind each optical frequency comb source, wherein the wavelength combinations contained in the optical pulses leaving different ports of the same encoder are different.
And 4, taking different optical comb intervals as a first code, and taking different combinations of wavelength components as a second code for each code word, wherein the final results of the two codes form a set of all codes.
The adjustable frequency comb source is characterized in that when the adjustable frequency comb source works in a wavelength range used by a light source, the size of a frequency comb modulated by the adjustable frequency comb source is close, the comb tooth space is kept stable, the generated frequency comb is equally spaced and is far smaller than the space of the central wavelength of adjacent light pulses, the number of comb teeth in one light pulse spectrum pattern is generally guaranteed to be 5 or more, and the space of the central wavelength of the light pulse can divide the frequency comb space evenly so as to ensure that each pulse has the same number of comb teeth in the wavelength range; the number of teeth of the comb falling into the light pulse is ensured to be obviously different among different light frequency comb sources, and n different codes can be generated through the adjustable light frequency comb sources with n different comb teeth.
The multiport wavelength encoder is formed by connecting 2 (m-1) -1 optical splitters in a one-to-two mode step by step, two output ports of an upper optical splitter are respectively connected with input ports of two optical splitters of a lower level, only one optical fiber grating is selected from the two output ports of one optical splitter to be placed, each optical fiber grating can completely reflect one wavelength generated by a light source and transmit other wavelengths, and all the optical fiber gratings used in each level have the same parameter indexes (such as central wavelength reflectivity and 3dB bandwidth). Since the optical pulse output must be guaranteed, each port of the encoder should hold pulses of at least one wavelength, thus enabling a total of 2 (m-1) wavelength codes to be calculated using m wavelengths of light.
In the above scheme, n×2 (m-1) codes, each of which can uniquely correspond to one fiber link, can be generated using an optical frequency comb containing m wavelength optical pulses and n intervals.
The invention relates to an optical frequency comb source, which generates frequency combs on optical pulses at different intervals, light leaving each optical frequency comb source enters an optical fiber grating encoder, a cascade grating positioned in the optical frequency comb source selectively reflects pulse wavelengths, unique pulse wavelength combinations are formed at output ports, all encoders connected with the optical frequency comb source have the same structure, the output ports of the encoders are connected to all optical fiber links in a descending mode, for a certain link, the optical pulses entering the optical frequency comb source form unique coding information in the combination of the interval width of the comb teeth in a wavelength domain and the wavelength combination type.
FIG. 2 is a spectrum of an optical pulse output by a multi-wavelength laser. An optical pulse is formed by combining a plurality of pulses with different center wavelengths, the distances between adjacent center wavelengths are the same, and the main frequency components of the wavelengths are not overlapped.
FIG. 3 is a spectral diagram of an optical pulse after passing through a tunable optical frequency comb source. In order to ensure that the pulses at each center wavelength are all generated with the same number of comb teeth, the optical frequency comb source should generate frequency combs at fixed frequency intervals, and the intervals should be far smaller than the intervals of the center wavelengths of the pulses, usually, the number of comb teeth in one optical pulse spectrum pattern is ensured to be 5 or more, and the intervals of the center wavelengths of the optical pulses can divide the frequency comb intervals, so that the purpose is to ensure that the same number of frequency comb teeth can be generated in the bandwidth of each wavelength, ensure that the number of comb teeth is as large as possible, and simultaneously, one comb tooth exists at the center wavelength, and the comb teeth are symmetrically distributed in each wavelength by taking the center as an axis.
Fig. 4 is a diagram of a fiber grating encoder. The encoder is formed by connecting a plurality of one-to-two optical splitters step by step, two output ports of an upper optical splitter are respectively connected with input ports of two lower optical splitters, only one optical fiber grating is selected from the two output ports of one optical splitter to be placed, each optical fiber grating can completely reflect one wavelength generated by a light source and transmit other wavelengths, and all the optical fiber gratings used in each stage have the same parameter indexes (such as central wavelength reflectivity and 3dB bandwidth). Since the optical pulse output must be guaranteed, each port of the encoder should hold pulses of at least one wavelength, thereby enabling calculation of 2 wavelength codes achievable using m optical wavelengths altogether (m-1).
FIG. 5 is a graph of the spectrum of an optical pulse exiting a port of a 6-wavelength fiber grating encoder. Wherein the same number of teeth is present in several selected wavelength ranges (lambda 1,λ3,λ5,λ6), the number of teeth and the combination of wavelengths together being the unique coded information of one optical link.
The embodiment of the invention enumerates specific implementation flow of the dense optical fiber coding method based on the optical frequency comb and the optical fiber grating, and the number of optical wavelengths used in the method and the comb teeth of the adjustable optical frequency comb source can be adjusted according to practical conditions.
Claims (2)
1. A compact optical fiber coding method based on an adjustable optical frequency comb source and an optical fiber grating is characterized in that: the method comprises the following steps:
Step 1, a C-band pulse signal is sent out by a light source module, wherein the C-band pulse signal comprises m optical pulses with different central wavelengths and overlapped in a time domain;
Step 2, dividing the optical pulse into n different adjustable optical frequency comb sources by utilizing an optical divider, wherein each adjustable optical frequency comb source generates comb teeth on an optical pulse wavelength domain at fixed optical comb intervals, and the optical comb intervals generated by the different adjustable optical frequency comb sources are different; when the adjustable optical frequency comb source works in the wavelength range used by the light source module, the generated optical comb intervals are equal and smaller than the intervals of the adjacent optical pulse center wavelengths, and the optical comb intervals can be divided by the intervals of the optical pulse center wavelengths; generating n different codes by n different optical comb spaced adjustable optical frequency comb sources;
Step 3, each adjustable optical frequency comb source is connected with a2 (m-1) -port wavelength encoder, and the wavelength combinations contained in the optical pulses leaving different ports of the same wavelength encoder are different; the wavelength encoder is formed by connecting 2 (m-1) -1 one-to-two optical splitters step by step, two output ports of the one-to-two optical splitters at the upper stage are respectively connected with input ports of the two one-to-two optical splitters at the lower stage, and only one port is selected from the two output ports of the one-to-two optical splitters to place one fiber grating; each fiber bragg grating totally reflects one of the wavelengths generated by the light source module and transmits the other wavelengths, and the fiber bragg gratings used in each stage have the same parameter index; each port of the wavelength encoder at least retains an optical pulse of one wavelength; 2 (m-1) kinds of wavelength codes can be realized by using m kinds of light wavelengths;
Step 4, taking different optical comb intervals as a first code, and taking different combinations of wavelength components as a second code for each code word, wherein the final results of the two codes form a set of all codes; the use of an adjustable optical frequency comb source comprising optical pulses of m optical wavelengths and n optical comb spacings produces a total of n x 2 (m-1) codes, each code uniquely corresponding to one fiber optic link.
2. The method for dense optical fiber coding based on tunable optical frequency comb sources and fiber gratings according to claim 1, wherein: the light source module receives external signal control, m laser arrays generate m light pulses with the same width, power and period in the time domain, different center wavelengths in the wavelength domain and the same 3dB bandwidth, the interval between the center wavelengths of adjacent light pulses is larger than the bandwidth of the adjacent light pulses so as to ensure that each light pulse cannot be aliased in the wavelength domain, and each light pulse leaves the laser at the same time and is combined into one pulse in the time domain through a coupler built in the light source module.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210726315.9A CN115102623B (en) | 2022-06-23 | 2022-06-23 | Dense optical fiber coding method based on optical frequency comb and optical fiber grating |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210726315.9A CN115102623B (en) | 2022-06-23 | 2022-06-23 | Dense optical fiber coding method based on optical frequency comb and optical fiber grating |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN115102623A CN115102623A (en) | 2022-09-23 |
| CN115102623B true CN115102623B (en) | 2024-08-16 |
Family
ID=83293818
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210726315.9A Active CN115102623B (en) | 2022-06-23 | 2022-06-23 | Dense optical fiber coding method based on optical frequency comb and optical fiber grating |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115102623B (en) |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7917039B1 (en) * | 2007-02-09 | 2011-03-29 | University Of Central Florida Research Foundation, Inc. | Signal processing using spectrally phase-encoded optical frequency combs |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2010200244A (en) * | 2009-02-27 | 2010-09-09 | Oki Electric Ind Co Ltd | Method of decoding code, optical pulse time spreading device, optical branch insertion device, and optical communication system |
| CN105187130A (en) * | 2015-08-17 | 2015-12-23 | 东南大学 | Fiber Bragg Grating (FBG) cascading shunt encoding device and encoding and decoding methods |
| CN105406918B (en) * | 2015-11-03 | 2017-11-10 | 南京航空航天大学 | A kind of photon type multifrequency phase encoded signal generation device and method |
| CN109560875B (en) * | 2018-12-28 | 2024-01-26 | 东南大学 | Fiber bragg grating coding device and method with temperature detection and compensation functions |
-
2022
- 2022-06-23 CN CN202210726315.9A patent/CN115102623B/en active Active
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7917039B1 (en) * | 2007-02-09 | 2011-03-29 | University Of Central Florida Research Foundation, Inc. | Signal processing using spectrally phase-encoded optical frequency combs |
Also Published As
| Publication number | Publication date |
|---|---|
| CN115102623A (en) | 2022-09-23 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP4055797B2 (en) | Optical cross-connect system | |
| US7702240B2 (en) | Optical multiplex communication system and delay quantity adjustment method | |
| CA1301946C (en) | Fast optical cross-connect for parallel processing computers | |
| WO2000010038A1 (en) | Time-wavelength multiple access optical communication systems and methods | |
| CN203968127U (en) | Multi-user's wavelength division multiplexing quantum key distribution network system | |
| CN117834005A (en) | An all-optical link monitoring system based on densely encoded weak reflectivity grating arrays | |
| Cheng et al. | Multiple access techniques for bipolar optical code division in wireless optical communications | |
| CN115102623B (en) | Dense optical fiber coding method based on optical frequency comb and optical fiber grating | |
| CN105071893A (en) | Novel large user capacity optical code division multiple access codec | |
| US7983561B2 (en) | Optical pulse time spreading device | |
| Kim | Cyclic optical encoders/decoders for compact optical CDMA networks | |
| EP1851513B1 (en) | Matrix time division multiplex (mtdm) interrogation | |
| CN115102618B (en) | Optical fiber coding method based on adjustable optical fiber F-P cavity and chirped fiber grating | |
| CN118533211A (en) | Large-scale grating array optical fiber sensing method for multi-wavelength pseudo-random multiplexing | |
| CN116300253A (en) | Optical fiber coding method based on binary amplitude keying and binary wavelength coding | |
| CN116318414A (en) | Intensive optical fiber coding method based on continuous light intensity modulation and fiber bragg grating | |
| CN116318415A (en) | Dense optical fiber coding method based on optical switch and weak reflectivity grating string | |
| CN110175018B (en) | Multi-wavelength parallel light quantum random number generator | |
| US8200089B2 (en) | Optical pulse time spreading apparatus and optical multiplex transmitting system with multiplexed channels and S/N ratio increased | |
| CN115733554B (en) | Optical fiber coding method based on sweep frequency laser and weak reflection grating array | |
| JP2011182052A (en) | Optical pulse time spreading device | |
| CN112054871B (en) | WDM-PON far-end shunt node with link monitoring function | |
| CN115603813A (en) | Fiber grating reflection-type variable encoder and method based on piezoelectric structure | |
| CN1284801A (en) | Dynamically configurable optical add/drop multiplexer | |
| Castro et al. | Compact OCDMA encoders based on the antisymmetric waveguide Bragg grating |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |