CN104993978B - The measurement method of train-ground communication transmission delay in Rail Transit System - Google Patents
The measurement method of train-ground communication transmission delay in Rail Transit System Download PDFInfo
- Publication number
- CN104993978B CN104993978B CN201510405476.8A CN201510405476A CN104993978B CN 104993978 B CN104993978 B CN 104993978B CN 201510405476 A CN201510405476 A CN 201510405476A CN 104993978 B CN104993978 B CN 104993978B
- Authority
- CN
- China
- Prior art keywords
- transmitting terminal
- receiving terminal
- data packet
- cpu
- terminal
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L43/00—Arrangements for monitoring or testing data switching networks
- H04L43/08—Monitoring or testing based on specific metrics, e.g. QoS, energy consumption or environmental parameters
- H04L43/0852—Delays
Abstract
An embodiment of the present invention provides a kind of measurement methods of train-ground communication transmission delay in Rail Transit System.This method includes:The time synchronization that the timer conter of CPU is carried out between transmitting terminal and receiving terminal, obtains the time deviation δ between the transmitting terminal and the receiving terminala；The transmitting terminal sends the data packet of the current count value Cs for the timer conter for carrying transmitting terminal CPU to the receiving terminal after the timed interval of setting arrives；After the receiving terminal receives the data packet, according to the current count value Cr, the current count value Cs of the timer conter of the transmitting terminal CPU and the time deviation δ of the timer conter of receiving terminal CPUaCalculate the end-to-end data transfer delay of the data packet.The embodiment of the present invention can accurately measure the data transfer delay of uplink and downlink during train fast moves in City Rail Transit System.
Description
Technical field
The present invention relates to train-ground communication transmission delays in technical field of rail traffic more particularly to a kind of Rail Transit System
Measurement method.
Background technology
As the communication technology especially radiotechnics develops rapidly, people begin one's study based on the communication technology
CBTC systems (Communication Based Train Control System, train operation control system).CBTC systems
, in real time transmission vehicle-ground two-way large capacity information reliable using wireless communication, train is in the process of running by radio communication
Earthward center sends the status informations such as the position of itself, speed to network in real time.It ground will centrally through cordless communication network
The information such as front obstacle, temporary speed limitation are sent to train.Train is according to front obstacle information, Train Parameters, line parameter circuit value
Etc. the real-time calculating speed curve of information, control train run under safe speed.
The characteristics of CBTC systems is the two-way communication that train and ground installation are realized with wireless communication media, to replace
Track circuit realizes Train Detection and Identification as media.The outstanding advantages of CBTC systems can be achieved on pair between vehicle-ground
It to communication, and transmits and contains much information, transmission speed is fast, it is easy to realize moving automatic block system, largely reduce section and apply
If cable, reduces one-time investment and reduce line service, carrying capacity of the block section can be increased substantially, flexible organization is double
It unidirectionally dispatches a car to operation and continuously, is easily adapted to the Train Detection and Identification etc. that different speeds, different freight volumes, different type are drawn
Deng.
The safe category information transmission of CBTC systems transmission includes train position information and ground that train is earthward sent
The Train Control information etc. sent to train.These information are data very high to security requirement, therefore, to train-ground communication
Reliability requirement is very high.For under the not high environment of QoS requirement, the communication delay of short time is acceptable, still
For communication reliability, the higher industrial control field of real-time has the break period of communication stringent limitation requirement,
In industrial real-time communication network, real time data can be subdivided into signal, order, state, event and request, in these real time datas
In, acyclic network-control or alarm priority highest account for about 9.5%；Acyclic processing data or event, preferentially
Grade is taken second place, and accounts for about 10%；Periodically third request and response processing priority, account for about the 80% of monitoring data amount, period
Property file transmission information, priority be the 4th, account for about 0.5%；Other non real-time data priorities are minimum.These are in real time
Data information has great significance for " steady, soon, accurate " of control, if causing real time information not have because of the delay of communication
There is delivered in real time, that will cause entire control system that cannot complete expected control targe, the serious wound that will also cause personnel
It dies.It is no, it is specified that the delay of train-ground communication and ground vehicle communication was no more than 0.5~2 second in IEEE 1474.1 (2004) standard
Then train will emergency braking.
At present industry for communication delay test often use dedicated communications field tool, such as Ping, Fastping,
Ixcharit etc., but these tools test be all data transmission two-way time, measurement result is data packet from one end
The other end is reached, the time then returned from the other end.This measurement method is in the wireless system of wired system or static state
There is good effect, because the transmission environment of uplink and downlink is essentially identical in such systems, the transmission delay of uplink and downlink can recognize
To be approximately uniform.Therefore the data two-way time divided by 2 that only needs test obtains of delay end to end are obtained with.
But in CBTC land mobile communication systems, due to fast moving for train, channel condition is sufficiently complex, switches and frequently occurs, on
The transmission delay of downlink will have prodigious difference.Therefore, it is not that the testing tool of traditional communication delay, which is used in CBTC systems,
Suitably.
Invention content
The embodiment provides a kind of measurement methods of train-ground communication transmission delay in Rail Transit System, with reality
Now effectively calculate train-ground communication transmission delay in Rail Transit System.
To achieve the goals above, this invention takes following technical solutions.
The measurement method of train-ground communication transmission delay in a kind of Rail Transit System, sets mobile unit and ground access is set
An equipment in standby is transmitting terminal, another equipment is receiving terminal, the method includes：
The time synchronization that the timer conter of CPU is carried out between the transmitting terminal and the receiving terminal, obtains the hair
Time deviation δ between sending end and the receiving terminala；
The transmitting terminal sends the timer conter for carrying transmitting terminal CPU after the timed interval of setting arrives
The data packet of current count value Cs gives the receiving terminal；
After the receiving terminal receives the data packet, according to the current count value Cr of the timer conter of receiving terminal CPU,
The current count value Cs of the timer conter of the transmitting terminal CPU and time deviation δaThe end for calculating the data packet is arrived
End data transmission delay.
Preferably, the time of the timer conter that CPU is carried out between the transmitting terminal and the receiving terminal is same
Further include before step：Track train is parked in a fixed position so that wireless between mobile unit and ground access device
Received signal strength is more than receiving sensitivity.
Preferably, the time of the timer conter that CPU is carried out between the transmitting terminal and the receiving terminal is same
Step, obtains the time deviation δ between the transmitting terminal and the receiving terminala, including：
Step a：After the timed interval for determining setting reaches, transmitting terminal is by the current meter of the timer conter of CPU
Numerical value Cs1 is inserted into the packet header of data packet, and the data packet is issued receiving terminal；
Step b：After the receiving terminal receives the data packet, the timer conter of the current CPU of record receiving terminal
Numerical value Cr, and counter values Cr is inserted into the packet header of the data packet received, then the data packet is returned into the hair
Sending end；
Step c：After the transmitting terminal receives the data packet that the receiving terminal returns, the current CPU of record transmitting terminal
Time counter value Cs2, from the data packet received extract first time transmission data packet when counter values Cs1, and
The counter values Cr of receiving terminal, calculates the time deviation between the transmitting terminal and receiving terminal when data packet reaches receiving terminal
δ：
δ=Cr/Fr- (Cs1+Cs2)/2Fs
The Fs is the count frequency of transmitting terminal timer conter.
Preferably, the method further includes：
Repeating said steps a-c obtains the time deviation δ between multiple transmitting terminal and receiving terminal, takes the multiple time inclined
Average value between poor δ obtains the final time deviation δ between transmitting terminal and receiving terminala。
Preferably, described to include after the timed interval for determining setting reaches：
If the when a length of T1 of the timed interval of setting, transmitting terminal read the timer conter of the CPU of sending device
Count frequency Fs reads the initial value of the timer conter of transmitting terminal CPU when timing starts, and after periodically starting, transmitting terminal is continuous
The current count value for updating timer counter, calculates current timing such as following formula:
T2=(C2-C1)/Fs
Wherein T2 is current timing, and C1 is the initial value of timer conter, and C2 is the current meter of timer counter
Numerical value, Fs are the count frequencies of transmitting terminal timer conter, work as T2>When=T1, it is determined that the timed interval of setting reaches.
Preferably, after the receiving terminal receives the data packet, according to the current of the timer conter of receiving terminal CPU
Count value Cr, the current count value Cs of the timer conter of the transmitting terminal CPU and the time deviation δaCalculate the number
According to the end-to-end data transfer delay of packet, including：
After receiving terminal receives data packet, the time counter value Cr of current receiving terminal CPU is recorded, extracts and is taken in data packet
The time counter value Cs of the CPU of the transmitting terminal delivery time of band, and combine previous time synchronous phase obtain transmitting terminal with
Final time deviation δ between receiving terminala, the transmitting terminal for calculating current data packet prolongs to the data transmission between receiving terminal
Chi Wei：
D=Cs/Fs-Cr/Fr- δa
Preferably, the method further includes：Repeat the end-to-end data transfer delay of the current data packet
Calculating process obtains continuous end-to-end data transfer delay in real time.
Preferably, the method further includes：The transmitting terminal is become into receiving terminal, the receiving terminal is become to send
End calculates transmitting terminal to the data transfer delay between receiving terminal, to individually again according to above-mentioned process flow
Transmitting terminal is calculated to receiving terminal, the data transfer delay of receiving terminal to transmitting terminal.
Preferably, CBTC systems are applied in the Rail Transit System.
By embodiments of the invention described above provide technical solution it can be seen from the embodiment of the present invention by elder generation in transmitting terminal
It is timed the time synchronization of counter between receiving terminal, then timing ga(u)ge is carried by being transmitted between transmitting terminal and receiving terminal
The data packet of the current count value Cs of number device, to calculate the end-to-end data transfer delay of data packet, so as to accurately survey
The data transfer delay of uplink and downlink during train fast moves in amount City Rail Transit System.This method is to evaluating city rail
The performance of road traffic land mobile communication system, is of great significance.
The additional aspect of the present invention and advantage will be set forth in part in the description, these will become from the following description
Obviously, or practice through the invention is recognized.
Description of the drawings
In order to illustrate the technical solution of the embodiments of the present invention more clearly, required use in being described below to embodiment
Attached drawing be briefly described, it should be apparent that, drawings in the following description are only some embodiments of the invention, for this
For the those of ordinary skill of field, without having to pay creative labor, other are can also be obtained according to these attached drawings
Attached drawing.
Fig. 1 is the measurement method of train-ground communication transmission delay in a kind of Rail Transit System that the embodiment of the present invention one provides
Process chart；
Fig. 2 is a kind of land mobile communication system structure chart of urban track traffic provided by Embodiment 2 of the present invention.
Specific implementation mode
Embodiments of the present invention are described below in detail, the example of the embodiment is shown in the accompanying drawings, wherein from beginning
Same or similar element or element with the same or similar functions are indicated to same or similar label eventually.Below by ginseng
The embodiment for examining attached drawing description is exemplary, and is only used for explaining the present invention, and is not construed as limiting the claims.
Those skilled in the art of the present technique are appreciated that unless expressly stated, singulative " one " used herein, " one
It is a ", " described " and "the" may also comprise plural form.It is to be further understood that is used in the specification of the present invention arranges
It refers to there are the feature, integer, step, operation, element and/or component, but it is not excluded that presence or addition to take leave " comprising "
Other one or more features, integer, step, operation, element, component and/or their group.It should be understood that when we claim member
Part is " connected " or when " coupled " to another element, it can be directly connected or coupled to other elements, or there may also be
Intermediary element.In addition, " connection " used herein or " coupling " may include being wirelessly connected or coupling.Wording used herein
"and/or" includes any cell of one or more associated list items and all combines.
Those skilled in the art of the present technique are appreciated that unless otherwise defined, all terms used herein (including technology art
Language and scientific terminology) there is meaning identical with the general understanding of the those of ordinary skill in fields of the present invention.Should also
Understand, those terms such as defined in the general dictionary, which should be understood that, to be had and the meaning in the context of the prior art
The consistent meaning of justice, and unless defined as here, will not be with idealizing or the meaning of too formal be explained.
For ease of the understanding to the embodiment of the present invention, done further by taking several specific embodiments as an example below in conjunction with attached drawing
Explanation, and each embodiment does not constitute the restriction to the embodiment of the present invention.
Embodiment one
The present invention is for communication interruption time caused by channel switching possibility in CBTC land mobile communication systems, it is proposed that a kind of
The measurement method of train-ground communication transmission delay in Rail Transit System, the specific process flow of this method is as shown in Figure 1, including such as
Under processing step：
Step S110：Train is parked in a fixed position so that the channel between mobile unit and ground access device
Good environment in sighting distance so that the wireless reception of signals intensity between mobile unit and ground access device, which is more than, receives spirit
Sensitivity.Above-mentioned mobile unit can be vehicle-mounted mobile platform.
Step S120：Transmitting terminal (can be mobile unit can also be ground access device) is sent with specified time interval
The data packet of specified size, proceeds by the synchronous flow of the timer conter of the CPU between transmitting terminal and receiving terminal：
A. it is the precision for improving measurement result, transmitting terminal uses timing technology, is T1 when needing deadline interval
Accurate timing when, transmitting terminal read sending device CPU timer conter count frequency Fs, then read timing start
When CPU timer conter initial value, after periodically starting, transmitting terminal constantly update timer counter current count value,
Calculate current timing such as following formula:
T2=(C2-C1)/Fs (1)
Wherein T2 is current timing, and C1 is the initial value of timer conter, and C2 is the current meter of timer counter
Numerical value, Fs are the count frequencies of transmitting terminal timer conter.
As current fixed time interval T2>When=T1, periodically terminate, as long as the CPU that transmitting terminal uses has sufficiently high performance, this
Kind timing accuracy can reach 1us.
After timing arrival, the current count value Cs1 of the timer conter of CPU is inserted into the packet of data packet by transmitting terminal
In head, and data packet is issued into receiving terminal.
B. after receiving terminal receives data packet, the timer conter numerical value Cr of the current CPU of record receiving terminal, and should
Counter values Cr is inserted into the packet header of the data packet received, which is returned to transmitting terminal.
C. after transmitting terminal receives the data packet that receiving terminal returns, the time counter value Cs2 of current CPU is recorded,
Counter values Cs1 and data packet when then extracting first time transmission data packet from data packet connect when reaching receiving terminal
The counter values Cr of receiving end, using the numerical value of these three counters, we can obtain following two equatioies：
Cs1/Fs+d1+ δ=Cr/Fr
(2)
Cr/Fr+d2- δ=Cs2/Fs
In above formula, d1 is transmission delay of the transmitting terminal to receiving terminal, and d2 is transmission delay of the receiving terminal to transmitting terminal, and δ is
Time deviation between transmitting terminal and receiving terminal, Fs and Fr are the CPU count frequencies of transmitting terminal and receiving terminal respectively.Due at this time
The channel of mobile unit and ground access device is in the good environment of sighting distance, the transmission delay of uplink and downlink we can approximation recognize
To be equal, therefore using formula (3), d1, d2 eliminated, the time deviation between transmitting terminal and receiving terminal can be obtained
δ=Cr/Fr- (Cs1+Cs2)/2Fs (3)
D. step a-c is repeated, the time deviation δ between multiple transmitting terminal and receiving terminal is obtained, then takes the multiple time
Average value between deviation δ obtains the final time deviation δ between transmitting terminal and receiving terminala。
Step S130：After completing the time synchronization between transmitting terminal and receiving terminal, the survey of delay time can be started
Amount, testing procedure are as follows：
Transmitting terminal (can be train can also be ground) sends the data packet for specifying size with specified time interval.It sends
End uses timing technology, and after timing arrival, the current count value Cs of the timer conter of CPU is inserted by transmitting terminal
Header data packet header, and data packet is issued into receiving terminal.
Step S140：After receiving terminal receives data packet, the time counter value Cr of itself current CPU is recorded, number is extracted
According to the time counter value Cs of the CPU of the transmitting terminal delivery time carried in packet, and combine the transmitting terminal that synchronous phase obtains with
Final time deviation δ between receiving terminala, the transmitting terminal for calculating current data packet prolongs to the data transmission between receiving terminal
Chi Wei：
D=Cs/Fs-Cr/Fr- δa (4)
Step S130, step S140 are repeated, measures and obtains continuous end-to-end data transfer delay in real time.
In practical applications, transmitting terminal can be become receiving terminal by the role exchange between transmitting terminal and receiving terminal,
Receiving terminal is become into transmitting terminal.Then, the same processing procedure executed above, calculates receiving terminal to the data between transmitting terminal
Transmission delay.Therefore, the method for the embodiment of the present invention can individually calculate transmitting terminal to receiving terminal (uplink), receiving terminal
To the data transfer delay of transmitting terminal (downlink).
Embodiment two
A kind of land mobile communication system structure for urban track traffic that the embodiment provides is as shown in Figure 2.We are to measure
For downstream propagation delay (test of uplink is essentially identical, it is only necessary to transmitting terminal and receiving terminal location swap), such as Fig. 2 institutes
Show, when train operation outbound, stops in the good position of channel condition, then, complete the CPU between transmitting terminal and receiving terminal
Run time synchronizes, and synchronizing process is as follows：
UDP (User Datagram Protocol, User Datagram Protocol) is used between sending device and receiving device
Communication, transmitting terminal use timing technology, reads the timing frequency Fs and counter of the precision timer of sending device CPU
Value Cs, the timing frequency with the difference of timer twice divided by timer are exactly fixed time interval, once fixed time interval is equal to set
Fixed 10ms sends interval, and CPU counter value is just inserted into the packet header of data packet, the data packet of 100byte is sent to by transmitting terminal
Receiving terminal.After receiving terminal receives data, the timer value Cr of the timer conter of the CPU of data packet arrival time is recorded,
And timer value Cr is inserted into the packet header of data packet, data packet is returned into transmitting terminal.Transmitting terminal is calculated according to formula (2) and is completed
The primary calculating of time deviation δ between transmitting terminal and receiving terminal, above-mentioned time deviation δ are also both ends CPU run times offset
Amount.Above procedure is then repeated several times, obtains the time deviation δ between average transmitting terminal and receiving terminal.
After completion synchronizes, train brings into operation, and measuring phases start：
Transmitting terminal sends the data packet for specifying size with specified time interval.In this experiment, we are arranged between transmission
Every being 10ms, data package size is 100Bytes.Transmitting terminal uses timing technology, after timing arrival, transmitting terminal
The current value Cs of CPU counter is inserted into header data packet header, and data packet is issued into receiving terminal.Receiving terminal receive data packet with
Afterwards, itself current CPU counter value is recorded, extracts the CPU counter value Cs of transmitting terminal delivery time, and obtain in conjunction with synchronous phase
The both ends CPU run time deviations obtained calculate the transmission end-to-end delay of current data packet according to formula (3).In the operation of train
In the process, transmitting terminal persistently carries out sending and receiving for data with receiving terminal, can thus obtain in train travelling process in real time,
The real-time measurement of downstream propagation delay.
In conclusion the time that the embodiment of the present invention is timed counter by elder generation between transmitting terminal and receiving terminal is same
Step, then the data packet by transmitting the current count value Cs for carrying timer conter between transmitting terminal and receiving terminal, to calculate
The end-to-end data transfer delay for going out data packet fast moved so as to accurately measure train in City Rail Transit System
The data transfer delay of uplink and downlink in journey.This method has important the performance of evaluation urban rail-transport vehicle-ground communication system
Meaning.
The embodiment of the present invention is by by the role exchange between transmitting terminal and receiving terminal, can individually calculate transmission
The data transfer delay for holding receiving terminal (uplink), receiving terminal to transmitting terminal (downlink), it is multiple so as to be suitable for channel condition
The miscellaneous Rail Transit System for applying CBTC systems.
One of ordinary skill in the art will appreciate that：Attached drawing is the schematic diagram of one embodiment, module in attached drawing or
Flow is not necessarily implemented necessary to the present invention.
As seen through the above description of the embodiments, those skilled in the art can be understood that the present invention can
It is realized by the mode of software plus required general hardware platform.Based on this understanding, technical scheme of the present invention essence
On in other words the part that contributes to existing technology can be expressed in the form of software products, the computer software product
It can be stored in a storage medium, such as ROM/RAM, magnetic disc, CD, including some instructions are used so that a computer equipment
(can be personal computer, server either network equipment etc.) executes the certain of each embodiment of the present invention or embodiment
Method described in part.
Each embodiment in this specification is described in a progressive manner, identical similar portion between each embodiment
Point just to refer each other, and each embodiment focuses on the differences from other embodiments.Especially for device or
For system embodiment, since it is substantially similar to the method embodiment, so describing fairly simple, related place is referring to method
The part of embodiment illustrates.Apparatus and system embodiment described above is only schematical, wherein the conduct
The unit that separating component illustrates may or may not be physically separated, the component shown as unit can be or
Person may not be physical unit, you can be located at a place, or may be distributed over multiple network units.It can root
According to actual need that some or all of module therein is selected to achieve the purpose of the solution of this embodiment.Ordinary skill
Personnel are without creative efforts, you can to understand and implement.
The foregoing is only a preferred embodiment of the present invention, but scope of protection of the present invention is not limited thereto,
Any one skilled in the art in the technical scope disclosed by the present invention, the change or replacement that can be readily occurred in,
It should be covered by the protection scope of the present invention.Therefore, protection scope of the present invention should be with scope of the claims
Subject to.
Claims (8)
1. the measurement method of train-ground communication transmission delay in a kind of Rail Transit System, which is characterized in that setting mobile unit and
An equipment in the access device of ground is transmitting terminal, another equipment is receiving terminal, the method includes：
The time synchronization that the timer conter of CPU is carried out between the transmitting terminal and the receiving terminal, obtains the transmitting terminal
Time deviation δ between the receiving terminala；
The transmitting terminal sends the current of the timer conter for carrying transmitting terminal CPU after the timed interval of setting arrives
The data packet of count value Cs gives the receiving terminal；
It is described according to the current count value Cr of the timer conter of receiving terminal CPU after the receiving terminal receives the data packet
The current count value Cs of the timer conter of the transmitting terminal CPU and time deviation δaCalculate the end-to-end number of the data packet
According to transmission delay；
The time synchronization of the described timer conter that CPU is carried out between the transmitting terminal and the receiving terminal, described in acquisition
Time deviation δ between transmitting terminal and the receiving terminala, including：
Step a：After the timed interval for determining setting reaches, transmitting terminal is by the current count value of the timer conter of CPU
Cs1 is inserted into the packet header of data packet, and the data packet is issued receiving terminal；
Step b：After the receiving terminal receives the data packet, the timer conter numerical value of the current CPU of record receiving terminal
Cr, and counter values Cr is inserted into the packet header of the data packet received, then the data packet is returned into the transmitting terminal；
Step c：After the transmitting terminal receives the data packet that the receiving terminal returns, the record current CPU's of transmitting terminal determines
Hour counter value Cs2, counter values Cs1 and data from the data packet received when extraction first time transmission data packet
The counter values Cr of receiving terminal, calculates the time deviation δ between the transmitting terminal and receiving terminal when packet reaches receiving terminal：
δ=Cr/Fr- (Cs1+Cs2)/2Fs
The Fs is the count frequency of transmitting terminal timer conter, and Fr is the CPU count frequencies of receiving terminal.
2. the measurement method of train-ground communication transmission delay in Rail Transit System according to claim 1, which is characterized in that
Further include before the time synchronization of the timer conter for carrying out CPU between the transmitting terminal and the receiving terminal：It will
Track train is parked in a fixed position so that the wireless reception of signals intensity between mobile unit and ground access device is more than
Receiving sensitivity.
3. the measurement method of train-ground communication transmission delay in Rail Transit System according to claim 1, which is characterized in that
The method further includes：
Repeating said steps a-c obtains the time deviation δ between multiple transmitting terminal and receiving terminal, take multiple time deviation δ it
Between average value, obtain the final time deviation δ between transmitting terminal and receiving terminala。
4. the measurement method of train-ground communication transmission delay in Rail Transit System according to claim 2, which is characterized in that
The transmitting terminal setting timed interval arrive after, including：
If the when a length of T1 of the timed interval of setting, transmitting terminal read the counting of the timer conter of the CPU of sending device
Frequency Fs reads the initial value of the timer conter of transmitting terminal CPU when timing starts, and after periodically starting, transmitting terminal is constantly updated
The current count value of timer counter calculates current timing such as following formula:
T2=(C2-C1)/Fs
Wherein T2 is current timing, and C1 is the initial value of timer conter, and C2 is the current count value of timer counter,
Fs is the count frequency of transmitting terminal timer conter, works as T2>When=T1, it is determined that the timed interval of setting reaches.
5. the measurement method of train-ground communication transmission delay in Rail Transit System according to any one of claims 1 to 4,
It is characterized in that, after the receiving terminal receives the data packet, according to the current count value of the timer conter of receiving terminal CPU
Cr, the current count value Cs of the timer conter of the transmitting terminal CPU and the time deviation δaCalculate the data packet
End-to-end data transfer delay, including：
After receiving terminal receives data packet, the time counter value Cr of current receiving terminal CPU is recorded, is carried in extraction data packet
The time counter value Cs of the CPU of transmitting terminal delivery time, and the transmitting terminal for combining previous time synchronous phase to obtain and reception
Final time deviation δ between enda, the transmitting terminal of current data packet is calculated to the data transfer delay between receiving terminal
For：
D=Cs/Fs-Cr/Fr- δa。
6. the measurement method of train-ground communication transmission delay in Rail Transit System according to claim 5, which is characterized in that
The method further includes：The calculating process of the end-to-end data transfer delay of the current data packet is repeated, is obtained real
When continuous end-to-end data transfer delay.
7. the measurement method of train-ground communication transmission delay in Rail Transit System according to claim 6, which is characterized in that
The method further includes：The transmitting terminal is become into receiving terminal, the receiving terminal is become into transmitting terminal, according to above-mentioned processing
Flow, calculates transmitting terminal to the data transfer delay between receiving terminal again, to individually calculate transmitting terminal to connecing
The data transfer delay of receiving end, receiving terminal to transmitting terminal.
8. the measurement method of train-ground communication transmission delay in Rail Transit System according to claim 1, which is characterized in that
CBTC systems are applied in the Rail Transit System.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510405476.8A CN104993978B (en) | 2015-07-10 | 2015-07-10 | The measurement method of train-ground communication transmission delay in Rail Transit System |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510405476.8A CN104993978B (en) | 2015-07-10 | 2015-07-10 | The measurement method of train-ground communication transmission delay in Rail Transit System |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN104993978A CN104993978A (en) | 2015-10-21 |
| CN104993978B true CN104993978B (en) | 2018-08-07 |
Family
ID=54305734
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201510405476.8A Active CN104993978B (en) | 2015-07-10 | 2015-07-10 | The measurement method of train-ground communication transmission delay in Rail Transit System |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN104993978B (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109842603A (en) * | 2017-11-29 | 2019-06-04 | 北京通号国铁城市轨道技术有限公司 | A kind of method for synchronizing time and device |
| CN111008239B (en) * | 2018-10-07 | 2023-03-24 | 上海希路智能科技有限公司 | Data synchronization method and system of asynchronous system and terminal equipment |
| WO2020104017A1 (en) * | 2018-11-20 | 2020-05-28 | Nokia Technologies Oy | Latency-bounded packet delivery in mobile communication system |
| CN110086686B (en) * | 2019-03-08 | 2022-10-11 | 上海大学 | One-way transmission delay measurement method for train control data service of rail transit LTE-M communication system |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101753199A (en) * | 2009-12-22 | 2010-06-23 | 上海磁浮交通发展有限公司 | Vehicle-ground wireless communication synchronization maintenance method |
| CN103929263A (en) * | 2014-04-30 | 2014-07-16 | 北京华力创通科技股份有限公司 | Network communication method, network communication delay determining method and network communication local time synchronizing method |
| CN104079401A (en) * | 2014-06-19 | 2014-10-01 | 南京航空航天大学 | High-precision and short-period real-time communication procedure based on chain industry Ethernet |
| KR101472896B1 (en) * | 2013-12-13 | 2014-12-16 | 현대자동차주식회사 | Method and apparatus for enhancing security in in-vehicle communication network |
| CN104243079A (en) * | 2014-10-09 | 2014-12-24 | 四川省绵阳西南自动化研究所 | Microsecond clock synchronization method for real-time Ethernet |
| CN104486135A (en) * | 2014-11-18 | 2015-04-01 | 北京交控科技有限公司 | System and method for communication calibration of rail vehicle |
-
2015
- 2015-07-10 CN CN201510405476.8A patent/CN104993978B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101753199A (en) * | 2009-12-22 | 2010-06-23 | 上海磁浮交通发展有限公司 | Vehicle-ground wireless communication synchronization maintenance method |
| KR101472896B1 (en) * | 2013-12-13 | 2014-12-16 | 현대자동차주식회사 | Method and apparatus for enhancing security in in-vehicle communication network |
| CN103929263A (en) * | 2014-04-30 | 2014-07-16 | 北京华力创通科技股份有限公司 | Network communication method, network communication delay determining method and network communication local time synchronizing method |
| CN104079401A (en) * | 2014-06-19 | 2014-10-01 | 南京航空航天大学 | High-precision and short-period real-time communication procedure based on chain industry Ethernet |
| CN104243079A (en) * | 2014-10-09 | 2014-12-24 | 四川省绵阳西南自动化研究所 | Microsecond clock synchronization method for real-time Ethernet |
| CN104486135A (en) * | 2014-11-18 | 2015-04-01 | 北京交控科技有限公司 | System and method for communication calibration of rail vehicle |
Non-Patent Citations (2)
| Title |
|---|
| Research on the influence of communication delay on safety location of train in communication based train control;Lijie Chen;《Intelligent Vehicles Symposium》;20090714;全文 * |
| 网络条件下列车追踪模型及延迟传播的研究;荀径等;《物理学报》;20070930;第56卷(第9期);第5158-5164页 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN104993978A (en) | 2015-10-21 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN104993978B (en) | The measurement method of train-ground communication transmission delay in Rail Transit System | |
| CN100479361C (en) | Synchronous medium access controller | |
| CN102449940B (en) | Network synchronization method and apparatus for performing time synchronization between nodes | |
| CN110086686B (en) | One-way transmission delay measurement method for train control data service of rail transit LTE-M communication system | |
| CN106515790B (en) | A kind of auxiliary anti-collision early warning method based on bilateral round trip ranging | |
| CN107316348B (en) | Interference suppression method, electronic toll collection system and road side unit equipment | |
| EP1881339A1 (en) | An apparatus for multilateration and method | |
| ATE466348T1 (en) | METHOD FOR COMMUNICATION BETWEEN A CENTRAL STATION AND SEVERAL TRANSPONDERS AND A COMMUNICATION DEVICE | |
| CN104378823A (en) | Single-side synchronous bidirectional ranging method | |
| CN104931855A (en) | Power transmission line fault-based traveling wave header identification and extraction device and method | |
| DE102011107164A1 (en) | Method and system for locating a current position or a coupling point of a mobile unit by means of leaky waveguide | |
| CN107346981A (en) | Data transmission method for uplink, method of reseptance and data sending device, reception device | |
| WO2017165808A1 (en) | Methods and apparatus for clock drift mitigation with snoop-based ranging | |
| WO2014145430A1 (en) | Traffic analysis system using wireless networking devices | |
| CN108551378B (en) | A kind of radiofrequency signal remote transmission method | |
| CN105791042B (en) | Communication quality testing method in ETC system | |
| CN103607727A (en) | Method and equipment for testing performance of vehicle networking vehicle-road Zigbee wireless network | |
| CN102255791A (en) | Inter-equipment link delay determination method and system | |
| CN103383812B (en) | A kind of issue hourage system and method with being accurate to second | |
| CN104386093A (en) | Train positioning device and method | |
| RU2511760C1 (en) | Method of determining the track section non-occupancy at spans | |
| CN104809884A (en) | Over-speed vehicle detecting method and system | |
| CA2101216C (en) | Method of correcting measurement errors caused by clock deviations in a secondary radar system | |
| CN112600726B (en) | Multi-station networking real-time data interaction method | |
| CN106549822A (en) | The method of the response time of testing time sync message, device and test equipment |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |