CN102420947A - Digital television radio-frequency synchronous digital processing and overlaying method and system - Google Patents
Digital television radio-frequency synchronous digital processing and overlaying method and system Download PDFInfo
- Publication number
- CN102420947A CN102420947A CN2011103649072A CN201110364907A CN102420947A CN 102420947 A CN102420947 A CN 102420947A CN 2011103649072 A CN2011103649072 A CN 2011103649072A CN 201110364907 A CN201110364907 A CN 201110364907A CN 102420947 A CN102420947 A CN 102420947A
- Authority
- CN
- China
- Prior art keywords
- hobboing cutter
- digital
- frequency
- digital television
- signal
- 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.)
- Pending
Links
Images
Landscapes
- Mobile Radio Communication Systems (AREA)
Abstract
The invention relates to the technical field of digital television terrestrial broadcasting, in particular to a digital television radio-frequency synchronous digital processing and overlaying method and system. The invention aims at providing a digital television radio-frequency synchronous digital processing and overlaying method and system, wherein each synchronous digital processor in the system can process digital television radio-frequency signals with 40M bandwidth at most. Only one digital television signal source (key station) is required in one local (regional) overlay network, the digital television radio-frequency signals are converted into digital optical signals by the key station through a synchronous digital processor host machine, the digital optical signals are transmitted to other sites within the overlay network through an optical-fiber transceiver, and the signal source of the key station is forwarded by all sites, so as to solve the problems of frequency synchronization and code element synchronization. Time delay of a data transmission link can be calculated by all sites. The signal storage time can be independently adjusted by all sites. The digital television radio-frequency synchronous digital processing and overlaying system, provided by the invention, has the advantages of simple framework, good overlay effect, strong stability and low construction and operating costs, and can be widely applied to digital television transmission overlay networks.
Description
Technical field
The present invention relates to the DTTB technical field, be specially a kind of DTV radio frequency synchronous digital and handle covering method and system.
Background technology
At present, traditional SFN is made up of many digital transmitters, adopts the transmitting station of net distribution to realize covering on a large scale.Because all transmitters adopt same frequency emission, so require three precise synchronization: Frequency Synchronization, time synchronized, symbol synchronization.
For realizing system synchronization, mono-frequency network system has also increased key equipments such as SFN (SFN) adapter, GPS except encoder, modulator.Frequency Synchronization is realized by GPS that mainly the stability of general GPS reference clock can reach the 1E-12 magnitude; Frequency stability still can reach more than the 1E-10 in the losing lock 24 hours.Time synchronized is accomplished by SFN adapter and GPS jointly, and GPS provides accurate 1PPS pulse, and the SFN adapter of making a start carries out huge frame to the TS stream of importing and handles (MIP), and receive end and separate MIP, thus the requirement of realization time synchronized.Symbol synchronization realizes through the SFN adapter.Because the requirement of time synchronized, the distance between the adjacent transmission station has certain limitation.
Adopt this kind mode to set up the DTV nerve of a covering in broadband (multichannel), every many channels.Each covers website all needs a whole set of SFN equipment.The realization difficulty of its Frequency Synchronization, time synchronized, symbol synchronization is big, formation is complicated.
In order to develop the DTTB network system better sooner; The DTV Synchronous Processing and the transmission coverage mode that need development of new; Coverage effect is good, stability is strong to make up, and project cost is low and the low digital television transfer nerve of a covering of operating cost.
Summary of the invention
The object of the present invention is to provide a kind of DTV radio frequency synchronous digital to handle covering method and system, each the synchronous digital processor in the system can be handled 40M bandwidth numeral TV RF signals at most.A part (zone) nerve of a covering only needs a digital television signal source (central station); Central station converts the DTV radiofrequency signal into digital optical signal through synchronous digital processor main frame and is transferred to other websites in the nerve of a covering through fiber optical transceiver; The equal retransmission center of each website station signal source solves Frequency Synchronization, symbol synchronization problem with this.Each website can the calculated data transmission link time delay.And can the independent regulation signal storage time.With stationary problem settling time.Make interior each launch point of the area of coverage according to engine request adjustment emission time delay with crossing the time delay adjustment.Realize time synchronized, Frequency Synchronization, symbol synchronization between each launch point.
Technical scheme of the present invention is:
A kind of DTV radio frequency synchronous digital is handled covering method, may further comprise the steps:
A) configuration center station and remote terminal,
B) central station converts 40Mhz audio frequency and video source in the red-letter day radiofrequency signal of input to the digital fiber signal;
C) through the DTV synchronous digital processing host of central station the DTV synchronous digital that the digital fiber signal is sent to remote terminal is handled slave;
D) remote terminal again with above-mentioned signal forwarding to other remote terminals;
E) remote terminal digital optical signal that central station is sent is reduced into the DTV radiofrequency signal, and each remote terminal is reduced into and the reference clock identical with central station after receiving digital optical signal;
F) each remote terminal can finally be realized synchronous overlay network through perhaps manually time delay adjustment automatically.
The optical fiber that adopts between said central station and remote terminal, remote terminal and the remote terminal carries out transfer of data; In the optical fiber transmitting digital TV signal not with other signal mixed transport; Fiber optical transceiver adopts wavelength-division multiplex technique; Downlink transfer digital television signal, uplink control signal and each remote station equipment state-detection amount.
Said step b) may further comprise the steps:
Central station is given 2 frequency mixers with the DTV radiofrequency signal of input through the centimetre device;
Frequency through adopting different frequencies is combined, and 5 channel digital television radiofrequency signals are become 2 sections intermediate-freuqncy signals, and the reference clock of combining is frequently provided by baseband processing unit, and baseband processing unit provides simultaneously local clock is sent to remote terminal through fiber optical transceiver;
Is digital signal through No. 2 analog to digital converters with the analog signal conversion of importing;
To import intermediate-freuqncy signal through digital filter and realize thorough segmentation, one section for comprising 2 physical channel digital television informations, and one section comprises 3 physical channel digital television signals;
Convert digital signal into general international standard CPRI form interface through baseband processing unit, realize Optical Fiber Transmission through fiber optical transceiver.
Said step e) may further comprise the steps:
The baseband processing unit of remote terminal converts the fiber-optic signal that receives into digital signal and through digital filter, digital to analog converter digital signal is reduced into 2 sections intermediate-freuqncy signals; Wherein one section for comprising 2 physical channel digital television informations, and one section comprises 3 physical channel digital television signals;
Frequency through adopting different frequencies is combined, the output that makes 2 remote terminal frequency mixers through behind the mixer in a continuous frequency range;
Finally be reduced into 5 channel digital television radiofrequency signals.
The reference clock that the read-write clock of the work clock of said analog to digital converter, digital to analog converter and baseband processing unit, the data storage of baseband processing unit, the reference clock of combining have frequently all adopted central station to send.
A kind of DTV radio frequency synchronous digital is handled covering system; It is characterized in that it comprises central station and remote terminal; Said central station comprises DTV synchronous digital processing host, and DTV synchronous digital processing host comprises automatic gain control circuit, power splitter, central station frequency mixer, analog to digital converter, baseband processing unit, central station optical fiber transceiving unit; Automatic gain control circuit connects two-way central station frequency mixer through power splitter; Two-way central station frequency mixer connects the input of baseband processing unit respectively through an analog to digital converter; The output of baseband processing unit connects the central station optical fiber transceiving unit, and said optical fiber transceiving unit comprises many group fiber optical transceivers; Remote terminal comprises DTV synchronous digital processing slave; The DTV synchronous digital is handled slave and is comprised remote terminal optical fiber transceiving unit, baseband processing unit, digital to analog converter, remote terminal frequency mixer and mixer; Said remote terminal optical fiber transceiving unit connects the input of baseband processing unit; The output of baseband processing unit connects the remote terminal frequency mixer through digital to analog converter, and the remote terminal frequency mixer connects mixer; A central station connects one or more remote terminals through signal transmission link, and each remote terminal perhaps connects or independent existence through optical fiber and another corresponding remote terminal, forms the DTV networking structure.
Said DTV networking structure adopts honeycomb to distribute, and networking structure is multidiameter delay networking structure, multi-path serial networking structure, daisy networking structure or tree-like link-group web frame.
The networking structure of said multidiameter delay is that a plurality of outputs of a central station are connected with a plurality of remote terminals respectively; The networking structure of multi-path serial is that a central station and a plurality of remote terminal are connected in series successively; The networking structure of daisy is that a plurality of outputs of a central station are connected with a plurality of remote terminals respectively, and each remote terminal is connected in series with a plurality of remote terminals respectively; The networking structure of tree-like link is that the output that passes through of a central station is connected with a plurality of remote terminals respectively, and each remote terminal is connected in series with a plurality of remote terminals respectively.
Said baseband processing unit is the on-site programmable gate array FPGA module or is Digital Signal Processing DSP module.
Said remote terminal also comprises power amplifier unit, and power amplifier unit connects the mixer output, and power amplifier unit comprises the linear amplifying unit of the small-signal that connects successively, cavity body filter and power amplifier.
The invention has the beneficial effects as follows:
DTV synchronous digital processor of the present invention down-converts to intermediate-freuqncy signal with the DTV radiofrequency signal, converts digital signal to through ADC.The FPGA baseband processing unit converts digital signal into standard C PRI interface light signal and send optical transceiver, be transmitted through the fiber to remote terminal after, the FPGA baseband processing unit of remote terminal converts light signal to digital signal again.Digital signal converts intermediate-freuqncy signal to through DAC, and intermediate-freuqncy signal is reduced into the DTV radiofrequency signal after up-conversion.The reference clock that whole process adopts is central station and sends.Each remote terminal is reduced into and the reference clock identical with central station after receiving.The frequency of all reference clocks is in full accord in the system.Realize the Frequency Synchronization mode with this function replacement tradition networking applying GPS synchronised clock.
The advantage that DTV synchronous digital treatment system of the present invention has Frequency Synchronization, time synchronized, symbol synchronization, framework is simple and easy, coverage effect good, stability is strong, the project cost low operating cost is low, can be adaptable across the digital television transfer nerve of a covering.
Description of drawings
Fig. 1 is a structural representation of the present invention.
Fig. 2 is the structural representation of central station of the present invention.
Fig. 3 is the structural representation of remote terminal of the present invention.
Fig. 4 is a multidiameter delay networking structure sketch map of the present invention.
Fig. 5 is a multi-path serial networking structure sketch map of the present invention.
Fig. 6 is a daisy networking structure sketch map of the present invention.
Fig. 7 is of the present invention or tree-like link-group web frame sketch map.
Embodiment
Below in conjunction with accompanying drawing the present invention is further described:
A kind of DTV radio frequency synchronous digital is handled covering method, it is characterized in that may further comprise the steps:
A) configuration center station and remote terminal,
B) central station converts 40Mhz audio frequency and video source in the red-letter day radiofrequency signal of input to the digital fiber signal;
C) through the DTV synchronous digital processing host of central station the DTV synchronous digital that the digital fiber signal is sent to remote terminal is handled slave;
D) remote terminal again with above-mentioned signal forwarding to other remote terminals;
E) remote terminal digital optical signal that central station is sent is reduced into the DTV radiofrequency signal, and each remote terminal is reduced into and the reference clock identical with central station after receiving digital optical signal;
F) each remote terminal can finally be realized synchronous overlay network through perhaps manually time delay adjustment automatically.
A part (zone) nerve of a covering has only a central station, and fore-end and central station are formed data center, and fore-end is responsible for converting program source to the DTV radiofrequency signal.Central station converts the DTV radiofrequency signal to digital optical signal.The digital optical signal that remote terminal sends central station is reduced into the DTV radiofrequency signal.Realize the whole network coverage through different network construction forms.Digital television transfer covering system of the present invention comprises central station and remote terminal.Central station is responsible for converting the DTV radiofrequency signal into the digital fiber signal, and remote terminal is responsible for the digital fiber signal is reduced to the DTV radiofrequency signal.Remote terminal can be transmitted to other remote terminals once more with the central station signal.
The optical fiber that adopts between central station and remote terminal, remote terminal and the remote terminal carries out transfer of data; In the optical fiber transmitting digital TV signal not with other signal mixed transport; Fiber optical transceiver adopts wavelength-division multiplex technique; Downlink transfer digital television signal, uplink control signal and each remote station equipment state-detection amount.Said signal transmission link is a fiber optic network. adopt general international standard CPRI form interface.
Step b) may further comprise the steps:
Because the bandwidth constraints of analog to digital converter and digital to analog converter, central station is given 2 frequency mixers with the DTV radiofrequency signal of input through the centimetre device; Frequency through adopting different frequencies is combined, and 5 channel digital television radiofrequency signals are become 2 sections intermediate-freuqncy signals, and the reference clock of combining is frequently provided by baseband processing unit, and baseband processing unit provides simultaneously local clock is sent to remote terminal through fiber optical transceiver; Is digital signal through No. 2 analog to digital converters with the analog signal conversion of importing; To import intermediate-freuqncy signal through digital filter and realize thorough segmentation, one section for comprising 2 physical channel digital television informations, and one section comprises 3 physical channel digital television signals; Convert digital signal into general international standard CPRI form interface through baseband processing unit, realize Optical Fiber Transmission through fiber optical transceiver.
Step e) may further comprise the steps:
The baseband processing unit of remote terminal converts the fiber-optic signal that receives into digital signal and through digital filter, digital to analog converter digital signal is reduced into 2 sections intermediate-freuqncy signals; Wherein one section for comprising 2 physical channel digital television informations, and one section comprises 3 physical channel digital television signals;
Frequency through adopting different frequencies is combined, the output that makes 2 remote terminal frequency mixers through behind the mixer in a continuous frequency range; Finally be reduced into 5 channel digital television radiofrequency signals.
The reference clock that the read-write clock of the work clock of analog to digital converter, digital to analog converter and baseband processing unit, the data storage of baseband processing unit, the reference clock of combining have frequently all adopted central station to send.
Frequently combining the clock that adopts is the reference clock at remote terminal receiving center station, so be 0 in whole transmission course medium frequency error.Through CPU digital signal memory time of FPGA baseband processing unit is set, realizes time delay adjustment each remote terminal.Through realizing the Transmission Fibers measurement of length two-way time of computer center's station-remote terminal, remote terminal-remote terminal.For each remote terminal time delay adjustment in the network coverage provides reference.Reference clock and frequently comprehensive component frequency source, frequency source inserts the frequency converter module respectively.
The DTV radiofrequency signal down-converts to intermediate-freuqncy signal, converts digital signal to through ADC.The FPGA baseband processing unit converts digital signal into standard C PRI interface light signal and send optical transceiver, be transmitted through the fiber to remote terminal after, the FPGA baseband processing unit of remote terminal converts light signal to digital signal again.Digital signal converts intermediate-freuqncy signal to through DAC, and intermediate-freuqncy signal is reduced into the DTV radiofrequency signal after up-conversion.The reference clock that whole process adopts is central station and sends.Each remote terminal is reduced into and the reference clock identical with central station after receiving.The frequency of all reference clocks is in full accord in the system.Use the gps synchronised clock with this function replacement tradition networking and realize the Frequency Synchronization mode.
The reference clock that the read-write clock of the work clock of the ADC in the native system, DAC, FPGA, data storage, the reference clock of combining have frequently all adopted central station to send.
DTV radio frequency synchronous digital of the present invention is handled covering system, and central station and remote terminal all contain digital filter.Digital filter bandwidth 7.6M, the inclined to one side 400k of centre frequency suppresses greater than 35dBc.
Like Fig. 1, Fig. 2, Fig. 3; A kind of DTV radio frequency synchronous digital is handled covering system; It is characterized in that it comprises central station and remote terminal; Said central station comprises DTV synchronous digital processing host, and DTV synchronous digital processing host comprises automatic gain control circuit, power splitter, central station frequency mixer, analog to digital converter, baseband processing unit, central station optical fiber transceiving unit; Automatic gain control circuit connects two-way central station frequency mixer through power splitter; Two-way central station frequency mixer connects the input of baseband processing unit respectively through an analog to digital converter; The output of baseband processing unit connects the central station optical fiber transceiving unit, and said optical fiber transceiving unit comprises many group fiber optical transceivers; Remote terminal comprises DTV synchronous digital processing slave; The DTV synchronous digital is handled slave and is comprised remote terminal optical fiber transceiving unit, baseband processing unit, digital to analog converter, remote terminal frequency mixer and mixer; Said remote terminal optical fiber transceiving unit connects the input of baseband processing unit; The output of baseband processing unit connects the remote terminal frequency mixer through digital to analog converter, and the remote terminal frequency mixer connects mixer; A central station connects one or more remote terminals through signal transmission link, and each remote terminal perhaps connects or independent existence through optical fiber and another corresponding remote terminal, forms the DTV networking structure.
The DTV networking structure adopts honeycomb to distribute, and networking structure is multidiameter delay networking structure, multi-path serial networking structure, daisy networking structure or tree-like link-group web frame.
Like Fig. 4, Fig. 5, Fig. 6, Fig. 7, the networking structure of multidiameter delay is that a plurality of outputs of a central station are connected with a plurality of remote terminals respectively; The networking structure of multi-path serial is that a central station and a plurality of remote terminal are connected in series successively; The networking structure of daisy is that a plurality of outputs of a central station are connected with a plurality of remote terminals respectively, and each remote terminal is connected in series with a plurality of remote terminals respectively; The networking structure of tree-like link is that the output that passes through of a central station is connected with a plurality of remote terminals respectively, and each remote terminal is connected in series with a plurality of remote terminals respectively.
Baseband processing unit is the on-site programmable gate array FPGA module or is Digital Signal Processing DSP module.
Remote terminal also comprises power amplifier unit, and power amplifier unit connects the mixer output, and power amplifier unit comprises the linear amplifying unit of the small-signal that connects successively, cavity body filter and power amplifier.
Embodiment recited above describes preferred implementation of the present invention; Be not that design of the present invention and scope are limited; Do not breaking away under the design concept prerequisite of the present invention; Common engineers and technicians make technical scheme of the present invention in this area various modification and improvement all should fall into protection scope of the present invention, and the technology contents that the present invention asks for protection all is documented in claims.
?
Claims (6)
1. a rolling-type is cut bagging apparatus, it is characterized in that comprising edge bearing (2) and hobboing cutter device (3) and hobboing cutter drive unit, and said hobboing cutter device (3) is reciprocating under the drive of hobboing cutter drive unit, and the hobboing cutter blade of hobboing cutter device (3) contacts with edge bearing (2); Said hobboing cutter device (3) comprises hobboing cutter (3-1); Be provided with movable sleeve (3-2) in the hobboing cutter (3-1); Hobboing cutter (3-1) is arranged on the sliding shoe (4-1); Sliding shoe (4-1) flexibly connects lead (4-2), and sliding shoe (4-1) is connected with the hobboing cutter drive unit, and is reciprocating under the drive of hobboing cutter drive unit; Said movable sleeve (3-2) is a bearing; Said hobboing cutter drive unit is pneumatic actuating device (4), flexible gearing (6) or spindle gear (8).
2. rolling-type according to claim 1 is cut bagging apparatus, and it is fixing to it is characterized in that said hobboing cutter device (3) is connected with the pocket type automatic packaging machine through fixed mount (1).
3. rolling-type according to claim 1 is cut bagging apparatus; It is characterized in that said flexible gearing (6) comprises driving-belt or driving-chain; Driving-belt or driving-chain are connected with hobboing cutter device (3), and flexible gearing (6) also comprises connection driving-belt or transmission chain flexibility transfer motion power motor (7).
4. rolling-type according to claim 1 is cut bagging apparatus, it is characterized in that said spindle gear (8) comprises screw mandrel, screw mandrel slide block (9) and the screw mandrel transfer motion power motor (10) that connects screw mandrel.
5. rolling-type according to claim 1 is cut bagging apparatus, it is characterized in that said hobboing cutter (3-1) is dentation hobboing cutter (3-3), anodontia circular hobboing cutter (3-5), double-row type hobboing cutter (3-7) or many rows formula hobboing cutter.
6. rolling-type according to claim 1 is cut bagging apparatus, it is characterized in that said hobboing cutter device (3) also comprises hobboing cutter pressure-regulating device (5).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2011103649072A CN102420947A (en) | 2011-11-17 | 2011-11-17 | Digital television radio-frequency synchronous digital processing and overlaying method and system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2011103649072A CN102420947A (en) | 2011-11-17 | 2011-11-17 | Digital television radio-frequency synchronous digital processing and overlaying method and system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN102420947A true CN102420947A (en) | 2012-04-18 |
Family
ID=45945162
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2011103649072A Pending CN102420947A (en) | 2011-11-17 | 2011-11-17 | Digital television radio-frequency synchronous digital processing and overlaying method and system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN102420947A (en) |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1315387A2 (en) * | 2001-11-27 | 2003-05-28 | Pioneer Corporation | Video display apparatus |
| CN101150348A (en) * | 2006-03-28 | 2008-03-26 | 华为技术有限公司 | An outdoor distribution system and its networking method |
| CN101183903A (en) * | 2006-11-13 | 2008-05-21 | 深圳市皓华网络通讯有限公司 | Digital optical fiber repeater system |
| CN101500098A (en) * | 2009-02-13 | 2009-08-05 | 周颖平 | Transmission method and system for broadcast television signal |
| CN202353725U (en) * | 2011-11-17 | 2012-07-25 | 南京赛格微电子科技有限公司 | Digital television radio frequency synchronous digital processing cover system |
-
2011
- 2011-11-17 CN CN2011103649072A patent/CN102420947A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1315387A2 (en) * | 2001-11-27 | 2003-05-28 | Pioneer Corporation | Video display apparatus |
| CN101150348A (en) * | 2006-03-28 | 2008-03-26 | 华为技术有限公司 | An outdoor distribution system and its networking method |
| CN101183903A (en) * | 2006-11-13 | 2008-05-21 | 深圳市皓华网络通讯有限公司 | Digital optical fiber repeater system |
| CN101500098A (en) * | 2009-02-13 | 2009-08-05 | 周颖平 | Transmission method and system for broadcast television signal |
| CN202353725U (en) * | 2011-11-17 | 2012-07-25 | 南京赛格微电子科技有限公司 | Digital television radio frequency synchronous digital processing cover system |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP3585019B1 (en) | A communication device for providing digital transport of signals in a distributed antenna system | |
| KR102228617B1 (en) | Universal remote radio head | |
| CN103650387B (en) | The method and system of wireless transmission analog signal between antenna and BBP | |
| CN110069011B (en) | BD and GPS-based optical fiber remote centralized time service system and time service method | |
| CN102460997A (en) | Method of inserting CDMA beacon pilots in output of distributed remote antenna nodes | |
| CN100534010C (en) | TD-SCDMA system base station radio-frequency digital long-drawn optical fiber transmitting method and apparatus | |
| CN104581752A (en) | Method for concentrated transmission of multi-band and multisystem wireless signals | |
| CN113347699A (en) | Base station optical fiber time service system based on BD/GPS double antennas | |
| CN107295532B (en) | Optical fiber distribution system and communication method | |
| CN1728600A (en) | Method for implementing synchronous transmission for base station | |
| CN203027265U (en) | Digital processing type frequency modulation synchronized broadcasting exciter | |
| CN202353725U (en) | Digital television radio frequency synchronous digital processing cover system | |
| CN202353678U (en) | Radio frequency synchronous digital processor of digital television | |
| CN102420947A (en) | Digital television radio-frequency synchronous digital processing and overlaying method and system | |
| CN101500098B (en) | Transmission method and system for broadcast television signal | |
| US20240088949A1 (en) | Distributed antenna system and signal transmission method | |
| CN101287079B (en) | Transmission method, system and device for broadcast television signal | |
| CN102255679A (en) | System for adjusting transmission time of inputted signal of transmitter and realizing method thereof | |
| CN201393262Y (en) | Emitting system and device of radio and TV signals | |
| CN212785375U (en) | Wireless transmission assembly in time base transmission of time service optical fiber clock | |
| KR101035690B1 (en) | Antenna embedded remote radio head using a digital hub | |
| CN204887483U (en) | Wireless cover system based on WLAN control | |
| CN207910940U (en) | A kind of Novel digital television Single Frequency Network structure | |
| US20090017852A1 (en) | Transmitter, modulator and method for signal synchronization transmission in single frequency network transmission system | |
| CN118074742A (en) | Communication system and communication method suitable for tunnel |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| ASS | Succession or assignment of patent right |
Free format text: FORMER OWNER: GU CAIJUN LI GUIRONG Effective date: 20120419 Owner name: NANJING SAIGEW MICROWAVE SCIENCE + TECHNOLOGY CO., Free format text: FORMER OWNER: YU LI Effective date: 20120419 |
|
| C41 | Transfer of patent application or patent right or utility model | ||
| TA01 | Transfer of patent application right |
Effective date of registration: 20120419 Address after: 210031 J03-B, Liu Liu Industrial Park, Taishan Park, Nanjing hi tech Development Zone, Jiangsu, China Applicant after: Nanjing Saigew Microwave Science & Technology Co., Ltd. Address before: 210031 J03-B, Liu Liu Industrial Park, Taishan Park, Nanjing hi tech Development Zone, Jiangsu, China Applicant before: Yu Li Co-applicant before: Gu Caijun Co-applicant before: Li Guirong |
|
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20120418 |