CN201600772U - Wireless security alarm system and device - Google Patents
Wireless security alarm system and device Download PDFInfo
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- CN201600772U CN201600772U CN2009202979124U CN200920297912U CN201600772U CN 201600772 U CN201600772 U CN 201600772U CN 2009202979124 U CN2009202979124 U CN 2009202979124U CN 200920297912 U CN200920297912 U CN 200920297912U CN 201600772 U CN201600772 U CN 201600772U
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- alerting signal
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Abstract
The embodiment of the utility model discloses a wireless security alarm system and a device. The wireless security alarm system comprises a front-end wireless transmitting device and a wireless receiving device, the front-end wireless transmitting device includes a plurality of transmitters transmitting alarm signals in case of emergency, transmitted alarm signals of the transmitters are in different frequency ranges, and the wireless receiving device includes a plurality of receivers corresponding to the plurality of transmitters. Therefore, working frequency range of the transmitter-receiver of the system is different from that of other transmitter-receivers, and when one receiver working under certain frequency range suffers influenced by co-channel interference and adjacent channel interference, the receivers in other frequency ranges can normally communicate with the corresponding transmitters, thereby resolving the problem that an existing wireless security alarm system using a single frequency range misses alarming due to being intervened by same frequency or adjacent frequency.
Description
Technical field
The utility model relates to the wireless communication technique field, more particularly, relates to wireless security alarm system and device.
Background technology
Wireless security alarm system mainly (also can be described as the warning detecting devices by the front end wireless transmitting device, specifically can be a magnetic inductor, infrared inductor, microwave detector, ceiling type thermosonde, gas leakage detector, smoke alarm, flash appeal button etc.) and radio receiver (as the controlling alarm main frame) composition, large-scale wireless security alarm system then mainly is made up of front end wireless transmitting device, radio receiver and alarm monitoring center.When alert takes place, the front end wireless transmitting device utilizes its transmitter to send alerting signal to radio receiver, radio receiver then receives above-mentioned alerting signal by its receiver, and do corresponding alert according to this alerting signal and handle, as dial automatically preset number or with alarm monitoring center communication or the like.
At present, the main 315MHz of use (China and the U.S. use more) between the transmitter of front end wireless transmitting device and the receiver of radio receiver, 433MHz (China and Europe), 868MHz (Europe is used more), 915MHZ several open frequency ranges such as (U.S. use more) are carried out communication, and, only select for use single frequency band (such as 315M) to carry out communication between the transmitter of a general cover wireless security alarm system and the receiver, promptly only have the transmitter of launching 315M frequency range alerting signal on the front end wireless transmitting device and the receiver that only has reception 315M frequency range alerting signal on the radio receiver.This type systematic very easily is subjected to from various wireless devices, high-power electrical equipment, and the electromagnetic co-channel interference that produces of other various situations (as sunspot explosion, motor car engine, various motor, electric operation etc.) (comprising the malice co-channel interference that co-channel interference that the various wireless devices of operate as normal cause and offender utilize interference unit that wireless security alarm system is carried out) or adjacently disturb frequently.These all cause the normally alerting signal of receiving front-end wireless transmitting device transmission of radio receiver, the appearance that causes failing to report alert phenomenon.
The utility model content
In view of this, the utility model purpose is to provide wireless security alarm system and device, and existing to solve, as to be operated in single frequency band wireless security alarm system is because of being subjected to co-channel interference or the adjacent alert problem of failing to report that causes of disturbing frequently.
For achieving the above object, the utility model provides following technical scheme:
A kind of wireless security alarm system, comprise front end wireless transmitting device and radio receiver, described front end wireless transmitting device comprises a plurality of transmitters that send alerting signal when alert takes place, and the frequency of alerting signal that arbitrary transmitter sends is in different frequency ranges with the frequency of alerting signal that other transmitters send;
Described radio receiver comprises and described a plurality of transmitters receiver one to one.
A kind of front end wireless transmitting device comprise a plurality of transmitters that send alerting signal when alert takes place, and the frequency of alerting signal that arbitrary transmitter sends is in different frequency ranges with the frequency of alerting signal that other transmitters send.
A kind of radio receiver comprises a plurality of receivers, and the frequency of alerting signal that arbitrary receiver receives is in different frequency ranges with the frequency of alerting signal that other receivers receive.
From above-mentioned technical scheme as can be seen, front end wireless transmitting device in the utility model wireless security alarm system and radio receiver adopt a plurality of corresponding one by one transmitters and receiver to carry out communication, and the frequency range that arbitrary transmitter-receiver frequency range of working and other transmitter-receivers are worked is all inequality.When certain frequency range receiver of work suffers co-channel interference or adjacent the interference frequently and can't operate as normal the time, the receiver that works in other frequency ranges also can keep normal communication with corresponding transmitter, thereby has solved wireless security alarm system existing, that only use single frequency band because of being subjected to co-channel interference or the adjacent alert problem of failing to report that causes of disturbing frequently.
Description of drawings
In order to be illustrated more clearly in the utility model embodiment or technical scheme of the prior art, to do to introduce simply to the accompanying drawing of required use in embodiment or the description of the Prior Art below, apparently, accompanying drawing in describing below only is embodiment more of the present utility model, for those of ordinary skills, under the prerequisite of not paying creative work, can also obtain other accompanying drawing according to these accompanying drawings.
The wireless security alarm system structural representation that Fig. 1 is provided for the utility model embodiment;
Another structural representation of wireless security alarm system that Fig. 2 a is provided for the utility model embodiment;
The another structural representation of wireless security alarm system that Fig. 2 b is provided for the utility model embodiment;
The front end wireless transmitting device structural representation that Fig. 3 is provided for the utility model embodiment;
The radio receiver structural representation that Fig. 4 is provided for the utility model embodiment.
Embodiment
For quote and know for the purpose of, hereinafter the technical term of Shi Yonging, write a Chinese character in simplified form or abridge to sum up and be explained as follows:
ASK:Amplitude Shift Keying, amplitude shift keying;
OOK:On-Off Keying, the scale-of-two on off keying;
FSK:Frequency-shift keying, frequency shift keying;
GFSK:Gauss frequency Shift Keying, Gaussian Frequency Shift Keying;
Co-channel interference can drop on useful signal and receive the interior various electromagnetic interference (EMI) of passband;
Adjacent interference frequently, the interference between side frequency;
China stipulates the use of wireless security alarm system/device:
The frequency of utilization scope is 314-316MHz, 430-432MHz, and 433.00-434.79MHz;
Occupied bandwidth: be not more than 400kHz;
The duration of each wireless signal transmission is no more than 1 second.
Below in conjunction with the accompanying drawing among the utility model embodiment, the technical scheme among the utility model embodiment is clearly and completely described, obviously, described embodiment only is the utility model part embodiment, rather than whole embodiment.Based on the embodiment in the utility model, those of ordinary skills are not making the every other embodiment that is obtained under the creative work prerequisite, all belong to the scope of the utility model protection.
The utility model embodiment discloses a kind of wireless security alarm system, and existing to solve, as to be operated in single frequency band wireless security alarm system is because of being subjected to co-channel interference or the adjacent alert problem of failing to report that causes of disturbing frequently.
Fig. 1 shows a kind of structure of said system, comprises front end wireless transmitting device 11 and radio receiver 12, wherein:
Front end wireless transmitting device 11 is included in the transmitter 111 and 112 that sends alerting signal when alert takes place, and the frequency of transmitter 111 alerting signal that sends is in different frequency ranges with the frequency of transmitter 112 alerting signal that sends; Radio receiver 12 comprises and transmitter 111 and 112 receiver 121 and 122 one to one.
In China, wireless device works in 315MHz frequency range and 433MHz frequency range more, as there is not a special declaration, wireless device among all embodiment of the utility model (comprising front end wireless transmitting device and radio receiver) all is operated in 315MHz frequency range and these two frequency ranges of 433MHz, promptly has the transmitter or the receiver that work in 315MHz frequency range and 433MHz respectively.
Suppose that transmitter 111-receiver 121 works in the 315M frequency range, and transmitter 112-receiver 122 works in the 433M frequency range, above-mentioned two transmitters may run into following several co-channel interference or adjacent interference frequently:
Electromagnetic co-channel interference or adjacent frequency that receiver 121 is subjected to other normal wireless device generation of using disturb.At this moment, because the 433MHz frequency range is separated by far away apart from the 315M frequency range, therefore can cause co-channel interference or the adjacent electromagnetic wave that disturbs frequently to cause interference to receiver 122 for receiver 121, also be that transmitter 112 still can keep normal communication with receiver 122, and vice versa;
As seen, when front end wireless transmitting device 11 adopts 315M and two frequency ranges of 433M to carry out communication with radio receiver 12, if wherein certain frequency range is subjected to co-channel interference or adjacent interference frequently, another frequency range still can keep normal communication, thereby has solved wireless security alarm system existing, that only use single frequency band because of being subjected to co-channel interference or the adjacent alert problem of failing to report that causes of disturbing frequently.
Certainly, owing to be used for the frequency range of wireless device communication in the global range 315MHz, 433MHz, 868MHz and 915MHZ are arranged, therefore, when specific implementation, those skilled in the art can therefrom choose 2,3 and even 4 frequency range collocation uses (the many more level of securitys of use frequency range are also just high more) as required, the number that also is transmitter and receiver can be 2,3 or 4, and the frequency band that arbitrary emitter/receiver is worked is different from other emitter/receivers, does not give unnecessary details at this.
Need to prove that the wireless security alarm system that has at present adopts frequency hop spread spectrum to solve problem of co-channel interference.The characteristics of this technology are, in certain frequency range (such as 315M) bandwidth range, several frequencies of redirect automatically are set, when sending alerting signal, the transmitter of front end wireless transmitting device just taken (co-channel interference also takes place) by the miscellaneous equipment of same frequency as if a certain frequency, transmitter can jump to another frequency automatically and go to send alerting signal so, thereby reaches the purpose of anti-co-channel interference.But because frequency resource is limited, the bandwidth of a frequency range often has only 1-2MHz, and in so narrow bandwidth, selectable frequency hopping frequency is very limited.Thereby when Electromagnetic Interference that runs into the powerful device generation (bandwidth of the Electromagnetic Interference frequency that powerful device produces often surpasses the bandwidth of whole frequency hopping frequency range) or 315M full frequency band malicious interference, frequency hop spread spectrum has just lost the effectiveness of self.Therefore, existing frequency hopping can only be separated never by the interference of other normal same frequency wireless device that uses, but interference strong, that frequency coverage is bigger then can't be taken precautions against.And therefore the wireless security alarm system in the present embodiment does not exist the problems referred to above owing to be at least functioning on two frequency ranges.
In the above-described embodiments, a plurality of transmitters of front end wireless transmitting device are disposable transmission alerting signal simultaneously, also can send alerting signal according to certain sequential, can also repeatedly send same alerting signal by each transmitter.
When a cover comprises a more than front end wireless transmitting device in the wireless security alarm system, if just have a plurality of front end wireless transmitting devices to send alerting signal at synchronization just, the phenomenon of co-channel interference will appear in the alerting signal that above-mentioned a plurality of front end wireless transmitting devices are sent.Such as: two transmitters of front end wireless transmitting device 1 at a time send the alerting signal of 315MHZ and 433MHZ to radio receiver, just two transmitters of front end wireless transmitting device 2 also send the alerting signal of 315MHZ and 433MHZ to radio receiver at synchronization, so, wherein wherein will there be co-channel interference in alerting signal and the front end wireless transmitting device 2 of the 315MHz that sends of a transmitter between the alerting signal of the 315MHz of transmitter transmission to front end wireless transmitting device 1.In like manner, also can there be co-channel interference between the alerting signal of the 433MHz of the alerting signal of the 433MHz of front end wireless transmitting device 1 another transmitter transmission and 2 another transmitters transmissions of front end wireless transmitting device.The alerting signal that will cause front end wireless transmitting device 1 transmitter or front end wireless transmitting device 2 transmitters to send is like this missed.In addition, also may there be co-channel interference between overlapping in the wireless security alarm system more.
For avoiding the generation of above-mentioned situation, referring to Fig. 2 a, wireless security alarm system also can comprise transmit control device 201, is used to control the time interval that transmitter sends alerting signal.
Can include only the transmitter that a transmit control device is controlled all front end wireless transmitting devices in the one cover wireless security alarm system, also can control by all corresponding transmit control device of each front end wireless transmitting device, or the corresponding transmit control device of each transmitter is controlled.
For the co-channel interference that may exist between different front end wireless transmitting devices in the same wireless security alarm system, can solve in the following ways: when alert takes place in front end wireless transmitting device 11 and 13 locations simultaneously need be when radio receiver 12 sends alerting signals, two transmitters 111 of transmit control device 201 control front end wireless transmitting devices 11 and 112 are with 315MHz alerting signal and the 500ms transmission at interval of 433MHz alerting signal, and two transmitters 132 of control front end wireless transmitting device 13 and 131 are 315MHz alerting signal and the 800ms transmission at interval of 433MHz alerting signal, and front end wireless transmitting device 11 and 13 can guarantee that at least 433MHz alerting signal separately can be received by radio receiver 12 like this.Owing to be in the transmitting time of the alerting signal of two frequency ranges the interval is arranged in addition, two frequency range alerting signals send at interval can be avoided producing between the two frequency range alerting signals to shake when sending disturbing.Certainly, transmitter 111 and 112 interval times that send alerting signal also can be carried out dynamic change under the control of transmit control device 201, as when certain once alert takes place, it sends interval time is 500ms, and becomes 600ms or 300ms or the like when alert taking place next time.In like manner, transmitter 132 and 131 interval times that send alerting signal also can dynamic changes.Those skilled in the art can be provided with when specific implementation flexibly, as long as front end wireless transmitting device 11 and 13 has at least the alerting signal of a certain frequency range to be received by radio receiver 12 separately.And if front end wireless transmitting device quantity is 3,4 or other numbers and its location alert takes place simultaneously all, then can control with reference to aforesaid way, do not give unnecessary details at this;
Certainly, when each transmitter was reported to the police in the mode that repeatedly sends same alerting signal, transmit control device 201 also can send the mode of the interval time of alerting signal twice and avoids the co-channel interference between a plurality of front end wireless transmitting devices in the same system by each transmitter of control front end wireless transmitting device is adjacent.Such as: when alert takes place in front end wireless transmitting device 11 and 13 locations simultaneously need be when radio receiver sends warning message, 60s carries out the transmitter 111 and 112 of transmit control device 201 control front end wireless transmitting devices 11 with sending at interval for the second time with the transmission first of alerting signal respectively, and the transmitter 131 and 132 of control front end wireless transmitting device 13 70s carries out with sending at interval for the second time with the transmission first of alerting signal respectively, front end wireless transmitting device 11 and 13 can guarantee that at least the alerting signal that is sent the second time separately can be received by radio receiver 12 like this.
For many covers wireless security alarm system, can utilize the transmitter of front end wireless transmitting device in transmit control device control self system in the system separately to send interval time of 315MHz alerting signal and 433MHz alerting signal equally, make it with another system in to send interval time of two frequency range alerting signals different from the elimination co-channel interference; Perhaps, also can utilize transmit control device in the system separately to control in self system each transmitter sends first and sends alerting signal institute interlude once more, make it with another system in transmitter send first and send the different co-channel interferences of avoiding of alerting signal institute interlude once more, do not give unnecessary details at this.
In addition, also can avoid co-channel interference in conjunction with following manner: the order that the transmitter of a certain front end wireless transmitting device sends alerting signal is that the transmitter that works in the 315M frequency range sends alerting signal earlier, the transmitter that works in the 433MHz frequency range sends alerting signal again, and the order of another front end wireless transmitting device transmitter transmission alerting signal is just the opposite.
Preferably, referring to Fig. 2 b, the wireless security alarm system among above-mentioned all embodiment also can comprise attention device 202, is used for when all receivers all are interfered, and malicious interference takes place in caution.When specific implementation, can adopt the mode of warning lamp flicker or buzzer warning to warn, but also warning lamp and hummer use simultaneously certainly.
In existing single frequency band wireless security alarm system, have a kind of mode promptly to report to the police for being interfered: when radio receiver was interfered in coverage, system will warn the generation malicious interference.There is more serious false alarm phenomenon in this technical scheme, because a large amount of uses along with wireless device, air interference often takes place, but the ratio of malicious interference is lower, have only the talent conference of real preparation crime that wireless security alarm system is carried out malicious interference, the caution that this mode that therefore adopting is interfered promptly reports to the police is sent often all is a false alarm.Some producer improves for this reason, does not promptly send alerting signal when system is interfered at once, but (such as by 60 seconds) just warned after being subjected to interference to reach the regular hour, can reduce some false alarms like this, but not deal with problems fully.And the offender just can carry out PERIODIC INTERFERENCE (stop, and then then disturb) if understand this function after disturbing 50 seconds, and system just can not send caution, will cause new problem-fail to report the police like this, and its consequence is more serious.The attention device of present embodiment then is when the alerting signal of all frequency ranges all is interfered, and just malicious interference takes place in caution.Because the receiver operation of radio receiver is in 315M and two frequency ranges of 433M, these two frequency ranges are separated by far away, and the electromagnetic frequency range that other wireless devices of general operate as normal, powerful device and other various situations produce can be so not big.Therefore, when all receivers all were interfered, its reason was generally the offender wireless security alarm system has been carried out multifrequency or full range malicious interference.As seen, the accuracy rate of attention device caution generation malicious interference is quite high in the present embodiment.
In addition, the interference that wireless security alarm system also might be subjected to working in the normal wireless equipment of 315M frequency range simultaneously and work in the normal wireless equipment of 433M frequency range, in order further to improve the accuracy rate of caution, predeterminable duration of disturbance threshold values (as 1 second), all be interfered and duration of this interference when surpassing pre-set threshold value when all receivers like this, meaning just takes place attention device disturbs.
Corresponding with above-mentioned wireless security alarm system, referring to Fig. 3, the utility model embodiment also provides a kind of front end wireless transmitting device 31 simultaneously, front end wireless transmitting device 31 is included in the transmitter 311 and 312 that sends alerting signal when alert takes place, and the frequency of transmitter 311 alerting signal that sends is in different frequency ranges with the frequency of transmitter 312 alerting signal that sends.Certainly, the quantity of transmitter also can be 3 or 4, those skilled in the art can be provided with as required flexibly, are in different frequency ranges as long as guarantee the frequency of alerting signal that arbitrary transmitter sends with the frequency of alerting signal that other transmitters send, and do not give unnecessary details at this.
Preferably, referring to Fig. 3, front end wireless transmitting device 31 also can comprise transmit control device 32 and 33, is used to control the time interval that transmitter 311 and 312 sends alerting signal.
Corresponding with above-mentioned wireless security alarm system, referring to Fig. 4, the utility model embodiment also provides a kind of radio receiver 41 simultaneously, radio receiver 41 comprises receiver 42 and 43, and the frequency of receiver 42 alerting signal that receives is in different frequency ranges with the frequency of receiver 43 alerting signal that receives.Certainly, the quantity of receiver also can be 3 or 4, those skilled in the art can be provided with as required flexibly, are in different frequency ranges as long as guarantee the frequency of alerting signal that arbitrary receiver receives with the frequency of alerting signal that other receivers receive, and do not give unnecessary details at this.
Preferential, referring to Fig. 4, radio receiver 41 also can comprise attention device 44, is used for when receiver 42 and 43 all is interfered, malicious interference takes place in caution.
Need to prove, more than the front end wireless transmitting device is sent among all embodiment alerting signal can select different modulation systems as required, mix as ASK/OOK/FSK/GFSK etc. or multiple modulation system and use.And can select fixedly frequency or FHSS mode that alerting signal is received and dispatched, certainly, also fixedly frequency and FHSS mode are mixed use; Can select a kind of coded system (as fixed code, study sign indicating number, rolling code or other specific coding) also can multiple coded system mix use between front end wireless transmitting device and the radio receiver.
Each embodiment adopts the mode of going forward one by one to describe in this instructions, and what each embodiment stressed all is and the difference of other embodiment that identical similar part is mutually referring to getting final product between each embodiment.
To the above-mentioned explanation of the disclosed embodiments, make this area professional and technical personnel can realize or use the utility model.Multiple modification to these embodiment will be conspicuous concerning those skilled in the art, and defined herein General Principle can realize under the situation that does not break away from spirit or scope of the present utility model in other embodiments.Therefore, the utility model will can not be restricted to these embodiment shown in this article, but will meet and principle disclosed herein and features of novelty the wideest corresponding to scope.
Claims (9)
1. a wireless security alarm system comprises front end wireless transmitting device and radio receiver, it is characterized in that:
Described front end wireless transmitting device comprises a plurality of transmitters that send alerting signal when alert takes place, and the frequency of alerting signal that arbitrary transmitter sends is in different frequency ranges with the frequency of alerting signal that other transmitters send;
Described radio receiver comprises and described a plurality of transmitters receiver one to one.
2. the system as claimed in claim 1 is characterized in that, comprises that also the described transmitter of control sends the transmit control device in the time interval of alerting signal.
3. system as claimed in claim 1 or 2 is characterized in that, also is included in all receivers when all being interfered, and the attention device of malicious interference takes place in caution.
4. system as claimed in claim 3 is characterized in that described attention device comprises warning lamp and/or hummer.
5. a front end wireless transmitting device is characterized in that, comprise a plurality of transmitters that send alerting signal when alert takes place, and the frequency of alerting signal that arbitrary transmitter sends is in different frequency ranges with the frequency of alerting signal that other transmitters send.
6. equipment as claimed in claim 5 is characterized in that, comprises that also the described transmitter of control sends the transmit control device in the time interval of alerting signal.
7. a radio receiver is characterized in that, comprises a plurality of receivers, and the frequency of alerting signal that arbitrary receiver receives is in different frequency ranges with the frequency of alerting signal that other receivers receive.
8. equipment as claimed in claim 7 is characterized in that, also is included in all receivers when all being interfered, and the attention device of malicious interference takes place in caution.
9. system as claimed in claim 8 is characterized in that described attention device comprises warning lamp and/or hummer.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2009202979124U CN201600772U (en) | 2009-12-28 | 2009-12-28 | Wireless security alarm system and device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2009202979124U CN201600772U (en) | 2009-12-28 | 2009-12-28 | Wireless security alarm system and device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN201600772U true CN201600772U (en) | 2010-10-06 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2009202979124U Expired - Fee Related CN201600772U (en) | 2009-12-28 | 2009-12-28 | Wireless security alarm system and device |
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| CN (1) | CN201600772U (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105025550A (en) * | 2014-04-16 | 2015-11-04 | 上海诺司纬光电仪器有限公司 | Wireless frequency hopping scanning method |
| CN107331142A (en) * | 2017-08-07 | 2017-11-07 | 普诚创智（成都）科技有限公司 | Remote control coding/decoding system |
| CN107390284A (en) * | 2017-07-03 | 2017-11-24 | 厦门科牧智能技术有限公司 | A kind of infrared inductor and method |
-
2009
- 2009-12-28 CN CN2009202979124U patent/CN201600772U/en not_active Expired - Fee Related
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105025550A (en) * | 2014-04-16 | 2015-11-04 | 上海诺司纬光电仪器有限公司 | Wireless frequency hopping scanning method |
| CN107390284A (en) * | 2017-07-03 | 2017-11-24 | 厦门科牧智能技术有限公司 | A kind of infrared inductor and method |
| CN107331142A (en) * | 2017-08-07 | 2017-11-07 | 普诚创智（成都）科技有限公司 | Remote control coding/decoding system |
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| Date | Code | Title | Description |
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| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20101006 Termination date: 20171228 |