CN202121581U - Mobile communication system for use on high-speed train - Google Patents
Mobile communication system for use on high-speed train Download PDFInfo
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- CN202121581U CN202121581U CN2011202571042U CN201120257104U CN202121581U CN 202121581 U CN202121581 U CN 202121581U CN 2011202571042 U CN2011202571042 U CN 2011202571042U CN 201120257104 U CN201120257104 U CN 201120257104U CN 202121581 U CN202121581 U CN 202121581U
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Abstract
The utility model discloses a mobile communication system for use on high-speed train, comprising an omni antenna, a China Mobile GSM (Global System for Mobile communications) signal transceiver, a China Mobile TD (Time Division) signal transceiver, a China Unicom GSM signal transceiver, a China Unicom WCDMA (Wireless Code Division Multiple Access) signal transceiver, a China Unicom CDMA (Code Division Multiple Access) signal transceiver, a multisystem access platform and an antenna feed system. In the mobile communication system for use on high-speed train, antennas on the roof of high-speed train receive GSM, CDMA, TD-SCDMA and WCDMA signals along the railway; repeaters filter and amplify the signals; then decorative camouflage antennas or leak cables in carriages uniformly distribute the signals to each carriage to effectively cover the carriages; the decorative camouflage antennas or leak cables also receive the uplink signals of mobile phones in each carriage; the repeaters filter and amplify the uplink signals; and finally the antennas on the roof of high-speed train transmit the signals to the mobile communication base station of each system.
Description
Technical field
The utility model relates to wireless communication technology field, is specifically related to a kind of EMUs GSM of many net fusions that adopts and solves the GSM that the mobile communication signal enhancing on high-speed railway EMUs (CRH2, the CRH3) train covers.
Background technology
Railway be China main also be most important means of conveyance, the China's railway system train sends 1,600,000,000 person-times of passengers every year approximately.Along with 21 century science and technology accelerated development; Huge numbers of families have been popularized in informationization; Mobile phone is all used in friends and family's greeting and Working service contact all the time, and particularly present domestic part rail track has adopted the EMUs technology, because the EMUs admission fee is more expensive; Its high-end business visitor is numerous, and they have more urgent demand to the railway network quality.
But because the high-speed mobile of EMUs; The wireless signal of existing mobile technology (like GSM, CDMA) is under influence of various factors such as Doppler effect, multipath interference, handover, railway car shielding; Problems such as signal is weak, instability appear; Speech quality is poor ON TRAINS thereby cause GSM and CDMA, and GPRS or CDMA 1X speed of surfing the Internet more can't ensure, conversation and the easy call drop of data service go offline etc.; Bullet train particularly of new generation has a strong impact on mobile phone user's use experience.
Summary of the invention
The problem that the utility model will solve is: how the GSM that uses on a kind of bullet train is provided; The GSM that uses on this bullet train receives railway GSM along the line, CDMA, TD-SCDMA and WCDMA signal via the antenna that is installed in roof; Carrying out signal filtering through repeater equipment amplifies; By beautifying camouflage antenna or leaky cable in the compartment signal averaging is assigned in each compartment then; Each compartment is effectively covered, receive upward signal simultaneously, amplify after be installed in the mobile communication base station that the antenna transmission of roof is given each system through repeater filtering from cell phone in each compartment.
For reaching the foregoing invention purpose; The technical scheme that the utility model adopted is: the GSM that uses on a kind of bullet train is provided, it is characterized in that: comprise omnidirectional antenna, China Mobile GSM signal transmitting and receiving machine, the TD of China Mobile signal transmitting and receiving machine, the GSM of CHINAUNICOM signal transmitting and receiving machine, the WCDMA of CHINAUNICOM signal transmitting and receiving machine, the CDMA of China Telecom signal transmitting and receiving machine, multi-system access platform and antenna-feedback system; Said multi-system access platform comprises descending input stage multisystem splitter, descending ICS interference cancellation module, descending power amplifier module, up input stage multisystem splitter, up power amplifier module, up ICS interference cancellation module; Said China Mobile GSM signal transmitting and receiving machine, the TD of China Mobile signal transmitting and receiving machine, the GSM of CHINAUNICOM signal transmitting and receiving machine, the WCDMA of CHINAUNICOM signal transmitting and receiving machine are connected to the input of descending input stage multisystem splitter through electric bridge; The output of descending input stage multisystem splitter is connected respectively to corresponding downstream ICS interference cancellation module separately according to the standard of each communication system; Descending ICS interference cancellation module input is connected to the input of descending power amplifier module, and the output process electric bridge of descending power amplifier module is connected with transmitting antenna or the leaky cable in the antenna-feedback system; Transmitting antenna in the said antenna-feedback system or leaky cable are connected to the input of up input stage multisystem splitter through electric bridge; The output of up input stage multisystem splitter is connected respectively to the input of corresponding separately up ICS interference cancellation module according to the standard of each communication system; The output of up ICS interference cancellation module is connected to the input of up power amplifier module; The output of up power amplifier module is connected with the input of up input stage multisystem splitter, and the output of up input stage multisystem splitter is connected with omnidirectional antenna through electric bridge.
According to the GSM that uses on the bullet train that the utility model provided, it is characterized in that: the high speed agc circuit that also includes the 40dB great dynamic range of near-far interference between the donor base station that can self adaptation changes fast and the reception antenna.
According to the GSM that uses on the bullet train that the utility model provided, it is characterized in that: also include can the self adaptation motor-car GSM select frequency automatically functional module of the variation of host base station carrier in the way.
According to the GSM that uses on the bullet train that the utility model provided, it is characterized in that: the sluggish hand-off process module in sub-district that also includes the frequent switching that can reduce train travelling process.
In sum; That the GSM that uses on the bullet train that the utility model provided has is simple and reasonable, easy to use, cost of manufacture is low, measure advantages such as accurately quick; This depth of thread cubing utilization be the measuring principle of vernier caliper; During use, the numerical value on the dial drum of handle end face correspondence is the coarse value of the screwed hole degree of depth, and segment scale face is exact value (precision 0.05mm) with the respective value of the groove of the tube of carving characters on the handle.
Description of drawings
Fig. 1 is the connection sketch map of multi-system access platform;
Fig. 2 is the system construction drawing of bullet train GSM;
Fig. 3 is the processing procedure figure of ICS interference cancellation module;
Fig. 4 is the inside schematic diagram of GSM select frequency automatically module;
Fig. 5 is a GSM select frequency automatically algorithm block diagram;
Fig. 6 is the curve chart of the sluggish hand-off process module in sub-district.
Embodiment
Describe in detail below in conjunction with the embodiment of accompanying drawing the utility model:
The GSM that uses on this bullet train receives railway GSM along the line, CDMA, TD-SCDMA and WCDMA signal via the antenna that is installed in roof; Carrying out signal filtering through repeater equipment amplifies; By beautifying camouflage antenna or leaky cable in the compartment signal averaging is assigned in each compartment then; Each compartment is effectively covered; Receive upward signal simultaneously, amplify after be installed in the mobile communication base station that the antenna transmission of roof is given each system through repeater filtering from cell phone in each compartment.
As shown in the figure, the GSM that uses on this bullet train comprises omnidirectional antenna, China Mobile GSM signal transmitting and receiving machine, the TD of China Mobile signal transmitting and receiving machine, the GSM of CHINAUNICOM signal transmitting and receiving machine, the WCDMA of CHINAUNICOM signal transmitting and receiving machine, the CDMA of China Telecom signal transmitting and receiving machine, multi-system access platform and antenna-feedback system; Said multi-system access platform comprises descending input stage multisystem splitter, descending ICS interference cancellation module, descending power amplifier module, up input stage multisystem splitter, up power amplifier module, up ICS interference cancellation module; Said China Mobile GSM signal transmitting and receiving machine, the TD of China Mobile signal transmitting and receiving machine, the GSM of CHINAUNICOM signal transmitting and receiving machine, the WCDMA of CHINAUNICOM signal transmitting and receiving machine are connected to the input of descending input stage multisystem splitter through electric bridge; The output of descending input stage multisystem splitter is connected respectively to corresponding downstream ICS interference cancellation module separately according to the standard of each communication system; Descending ICS interference cancellation module input is connected to the input of descending power amplifier module, and the output process electric bridge of descending power amplifier module is connected with transmitting antenna or the leaky cable in the antenna-feedback system; Transmitting antenna in the said antenna-feedback system or leaky cable are connected to the input of up input stage multisystem splitter through electric bridge; The output of up input stage multisystem splitter is connected respectively to the input of corresponding separately up ICS interference cancellation module according to the standard of each communication system; The output of up ICS interference cancellation module is connected to the input of up power amplifier module; The output of up power amplifier module is connected with the input of up input stage multisystem splitter, and the output of up input stage multisystem splitter is connected with omnidirectional antenna through electric bridge.
The GSM that uses on this bullet train also includes the high speed agc circuit of the 40dB great dynamic range of near-far interference between the donor base station that can self adaptation changes fast and the reception antenna.The GSM that uses on this bullet train also include can the self adaptation motor-car GSM select frequency automatically functional module of the variation of host base station carrier in the way.The GSM that uses on this bullet train also includes the sluggish hand-off process module in sub-district of the frequent switching that can reduce train travelling process.
Multi-system access platform in the bullet train GSM (POI:Point Of Interface) is as the interface between the compartment system in plurality of communication systems and a plurality of zones, is deciliter to pass by the key component in the journey at the multisystem signal.Each road transceiver signal as shown in Figure 1 is all passed through independently port access multi-system access platform, outputs to the port of corresponding compartment system after the mixing; After will mixing from the signal of zones of different compartment system port simultaneously, deliver to the uplink port of signal source more on demand respectively.
As shown in Figure 2; Its down link is: omnidirectional's wideband reception antenna is connected to descending input stage multisystem splitter (POI to the aerial signal (comprising the TD-SCDMA/GSM of China Mobile, the WCDMA/GSM of CHINAUNICOM and the CDMA of China Telecom five road signals) that receives through electric bridge; Have duplex capability) input; The output of this splitter is connected respectively to corresponding separately ICS interference cancellation module according to the standard of each communication system; Realize a series of functions such as gain controlling, frequency-selecting, feedback interference elimination; Be input to after descending power amplifier module amplifies, output to descending input stage multisystem splitter (move, the GSM of UNICOM signal also will isolate differentiations), pass through electric bridge and be connected with transmitting antenna or leaky cable through isolator;
Its up link is: transmitting antenna or leaky cable are connected to the input of up input stage multisystem splitter through electric bridge; The output of this splitter is connected respectively to corresponding separately ICS interference cancellation module according to the standard of each communication system; Realize a series of functions such as gain controlling, frequency-selecting, feedback interference elimination; Be input to after power amplifier module amplifies; Output to up input stage multisystem splitter (mobile, the GSM of UNICOM signal also will be isolated differentiation through isolator), the output of this mixer is connected with omnidirectional antenna through electric bridge.
The active equipment of traditional analog requires isolation than the high 15dB of system gain; Reception antenna and transmitting antenna will draw back 30 meters ability and satisfy insulated degree requirement in practical engineering application; On the limited railway car in space, obviously can't satisfy mounting condition; The bullet train GSM adopts ICS (Interference Cancellation System) digital processing technology; Through adaptive-filtering (relating to signal correlation and Base-Band Processing), from the wireless receiving signal, detect feedback interference signal and counteracting, thereby when improving system gain; Greatly reduce the requirement of equipment, can accomplish that system gain is than the high 20dB no-self excitation of isolation isolation.
The implementation procedure of ICS module mainly is, through carrying out related operation receiving a signal with transmitting, detects feedback signal, generates the offseting signal of suitable phase place and power simultaneously, offsets computing in the counteracting link, thereby eliminated the feedback interference signal.
The ICS function is based on adaptive noise elimination realization, and is as shown in Figure 3:
In the running of train; The frequency of peripheral base station is in the continuous variation, use the frequency-selecting function that certain difficulty is arranged, and therefore a lot of producers have replaced frequency-selecting with simple selections; Promptly move the descending selection 930～954MHz of GSM frequency range, the descending selection 954～960MHz of the GSM of UNICOM frequency range; But directly adopt selections, can all receive into the signal in the whole frequency, operator's base station signal of peripheral non-donor base station all is an interference signal; Can seriously reduce the signal to noise ratio of donor signal, the risk that enlarges the signal contamination district has been arranged.
The bullet train GSM adopts GSM select frequency automatically module, and GSM equipment work frequency is divided into current collection and Active Set two parts.The concrete realization is through the software radio framework, and the GSM signal down-conversion of radio frequency is sampled changes into digital baseband signal, as shown in Figure 4; In fpga chip, designed the DDC passage of two-way, the one tunnel is the normal mode of operation passage, and the signal of current collection carrier frequency point is through this DDC passage; Realize normal signal transmission, for repeater signal provides normal service, other one the tunnel is select frequency automatically pattern passage; All frequencies of searching loop in the DDC passage of this road calculate the power of each frequency, reject the working frequency points near noise; Arrange the carrier frequency point of Active Set according to received field strength RX and carrier interference ratio C/I; Through the select frequency automatically algorithm, screen the current collection working frequency points that makes new advances at last, as shown in Figure 5.In gsm system (it is identical with UNICOM GSM processing method to move GSM), GSM select frequency automatically module has 18 passage frequency-selecting abilities, and wherein 12 passages are the normal mode of operation passage, and remaining 6 passages is select frequency automatically pattern passage.
The railway of Virtual network operator covers at present, is along the high speed railway construction base station basically, forms banded sub-district; Because running at high speed of train can frequently be crossed over the different base station sub-district, and frequent switching takes place; Too much switching has not only increased network burden, also causes call drop easily, has a strong impact on user experience; Particularly when certain base station cell coverage was too small, switching flow was accomplished in reaching that mobile phone does not also come, and train has rolled this base station cell coverage away from; The signal of this sub-district is in rapid attenuation, if mobile phone switches to this sub-district, is easy to cause call drop.
The bullet train GSM has adopted digitized processing; On the select frequency automatically technical foundation; Designed current collection and Active Set switching timer,, utilized timer to regulate the frequency that the service signal cell is switched in the compartment through intensity, the quality fluctuation model of analyzing each cell base station signal.Direct service high-speed train cellphone subscriber compares with the base station, through this technology, has reduced train and when sailing the little base station cell of coverage into, the frequent probability that switches has taken place, and reduces cutting off rate.Concrete implementation is as shown in Figure 6; In train operation, the signal strength signal intensity of base station cell 1 constantly descends, and the signal of base station cell 2 constantly strengthens; According to original base station switching law; The time of base station switch decision window is very short just to be through with, and user terminal needs to switch continually, is easy to call drop.The bullet train GSM is introduced new technology, constantly detects the carrier signal of Active Set at input, when the signal strength signal intensity of finding Active Set is better than current collection; Start switching timer, according to train speed per hour, the time Δ τ that the train effective operation is 500 meters; If in the time range of Δ τ; Signal in the Active Set does not still change, and then the signal with Active Set switches to current concentrating, and after power amplifier amplifies, covers the user area; If the signal in the Active Set changes, then begin new one and take turns timing ratio.Through this technology, as shown in Figure 6, the time span of repeater switch decision window is extended, and can reduce train the frequent probability that switches takes place when sailing the little base station cell of coverage into, reduces cutting off rate.
The above only is the preferred implementation of the utility model.Should be pointed out that for the present technique field, under the prerequisite that does not break away from the utility model principle, can also carry out some improvement and modification to the utility model, these improvement and modification also fall in the protection range of the utility model claim.
Claims (4)
1. the GSM that uses on the bullet train is characterized in that: comprise omnidirectional antenna, China Mobile GSM signal transmitting and receiving machine, the TD of China Mobile signal transmitting and receiving machine, the GSM of CHINAUNICOM signal transmitting and receiving machine, the WCDMA of CHINAUNICOM signal transmitting and receiving machine, the CDMA of China Telecom signal transmitting and receiving machine, multi-system access platform and antenna-feedback system; Said multi-system access platform comprises descending input stage multisystem splitter, descending ICS interference cancellation module, descending power amplifier module, up input stage multisystem splitter, up power amplifier module, up ICS interference cancellation module; Said China Mobile GSM signal transmitting and receiving machine, the TD of China Mobile signal transmitting and receiving machine, the GSM of CHINAUNICOM signal transmitting and receiving machine, the WCDMA of CHINAUNICOM signal transmitting and receiving machine are connected to the input of descending input stage multisystem splitter through electric bridge; The output of descending input stage multisystem splitter is connected respectively to corresponding downstream ICS interference cancellation module separately according to the standard of each communication system; Descending ICS interference cancellation module input is connected to the input of descending power amplifier module, and the output process electric bridge of descending power amplifier module is connected with transmitting antenna or the leaky cable in the antenna-feedback system; Transmitting antenna in the said antenna-feedback system or leaky cable are connected to the input of up input stage multisystem splitter through electric bridge; The output of up input stage multisystem splitter is connected respectively to the input of corresponding separately up ICS interference cancellation module according to the standard of each communication system; The output of up ICS interference cancellation module is connected to the input of up power amplifier module; The output of up power amplifier module is connected with the input of up input stage multisystem splitter, and the output of up input stage multisystem splitter is connected with omnidirectional antenna through electric bridge.
2. the GSM that uses on the bullet train according to claim 1 is characterized in that: the high speed agc circuit that also includes the 40dB great dynamic range of near-far interference between the donor base station that can self adaptation changes fast and the reception antenna.
3. the GSM that uses on the bullet train according to claim 1 and 2 is characterized in that: also include can the self adaptation motor-car GSM select frequency automatically functional module of the variation of host base station carrier in the way.
4. according to the GSM that uses on claim 1, the 2 or 3 described bullet trains, it is characterized in that: the sluggish hand-off process module in sub-district that also includes the frequent switching that reduces train travelling process.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
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| CN2011202571042U CN202121581U (en) | 2011-07-20 | 2011-07-20 | Mobile communication system for use on high-speed train |
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| Application Number | Priority Date | Filing Date | Title |
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| CN2011202571042U CN202121581U (en) | 2011-07-20 | 2011-07-20 | Mobile communication system for use on high-speed train |
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| CN202121581U true CN202121581U (en) | 2012-01-18 |
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| CN2011202571042U Expired - Fee Related CN202121581U (en) | 2011-07-20 | 2011-07-20 | Mobile communication system for use on high-speed train |
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Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102684733A (en) * | 2012-05-04 | 2012-09-19 | 西安亿力通微波科技有限公司 | Dual-network bidirectional orthogonal power synthesis system |
| CN102781062A (en) * | 2012-07-09 | 2012-11-14 | 中国科学院信息工程研究所 | Communication scheduling method and system and monitoring system and method |
| CN102883382A (en) * | 2012-09-27 | 2013-01-16 | 南京恩瑞特实业有限公司 | System and method for switching wireless media in rail transit |
| CN105656568A (en) * | 2014-11-24 | 2016-06-08 | 中国移动通信集团浙江有限公司 | Method and device for searching wireless electromagnetic ambient interference on high speed railway |
| CN112615634A (en) * | 2020-12-29 | 2021-04-06 | 江苏铁锚玻璃股份有限公司 | Vehicle window with public mobile communication signal enhancement function |
| CN113103969A (en) * | 2021-04-19 | 2021-07-13 | 北京绿程锦绣能源科技有限公司 | Mobile carrier with unauthorized carrier processing device |
| CN113259010A (en) * | 2021-05-20 | 2021-08-13 | 罗文松 | Optical transceiver access system based on multiple systems |
| CN116886137A (en) * | 2023-09-06 | 2023-10-13 | 中天射频电缆有限公司 | Cross polarization leaky cable MIMO communication system |
-
2011
- 2011-07-20 CN CN2011202571042U patent/CN202121581U/en not_active Expired - Fee Related
Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102684733A (en) * | 2012-05-04 | 2012-09-19 | 西安亿力通微波科技有限公司 | Dual-network bidirectional orthogonal power synthesis system |
| CN102781062A (en) * | 2012-07-09 | 2012-11-14 | 中国科学院信息工程研究所 | Communication scheduling method and system and monitoring system and method |
| CN102781062B (en) * | 2012-07-09 | 2015-11-11 | 中国科学院信息工程研究所 | Client/server adaptation scheme, system and monitoring system and method |
| CN102883382A (en) * | 2012-09-27 | 2013-01-16 | 南京恩瑞特实业有限公司 | System and method for switching wireless media in rail transit |
| CN102883382B (en) * | 2012-09-27 | 2015-11-11 | 南京恩瑞特实业有限公司 | Wireless medium switched system and method thereof in a kind of track traffic |
| CN105656568A (en) * | 2014-11-24 | 2016-06-08 | 中国移动通信集团浙江有限公司 | Method and device for searching wireless electromagnetic ambient interference on high speed railway |
| CN105656568B (en) * | 2014-11-24 | 2018-03-23 | 中国移动通信集团浙江有限公司 | The method and apparatus for searching interference of the high ferro wireless electromagnetic environment to GSM R |
| CN112615634A (en) * | 2020-12-29 | 2021-04-06 | 江苏铁锚玻璃股份有限公司 | Vehicle window with public mobile communication signal enhancement function |
| CN113103969A (en) * | 2021-04-19 | 2021-07-13 | 北京绿程锦绣能源科技有限公司 | Mobile carrier with unauthorized carrier processing device |
| CN113259010A (en) * | 2021-05-20 | 2021-08-13 | 罗文松 | Optical transceiver access system based on multiple systems |
| CN116886137A (en) * | 2023-09-06 | 2023-10-13 | 中天射频电缆有限公司 | Cross polarization leaky cable MIMO communication system |
| CN116886137B (en) * | 2023-09-06 | 2023-11-24 | 中天射频电缆有限公司 | Cross polarization leaky cable MIMO communication system |
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| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20120118 Termination date: 20160720 |
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| CF01 | Termination of patent right due to non-payment of annual fee |