WO2014036819A1

WO2014036819A1 - Collection and transmission method of real-time traffic information of limited region in front of automobile

Info

Publication number: WO2014036819A1
Application number: PCT/CN2013/072400
Authority: WO
Inventors: 杨华龙; 杨曦
Original assignee: Yang Hualong
Priority date: 2012-09-04
Filing date: 2013-03-11
Publication date: 2014-03-13
Also published as: CN102842241A

Abstract

A collection and transmission method of real-time traffic information of a limited region in front of an automobile. Based on an automotive navigation system, the method comprises a wireless communication system, a road and communication manner planning system, a real-time traffic information collection and processing system, a database system, and a real-time traffic information transmission system. The present invention transmits information in a radio broadcasting communication manner. A road is divided into regions and communication resources are allocated to the regions. Automobiles in each region exchange information mutually and determine speed information in the region and an information transmitter. The information transmitter transmits real-time traffic information of the limited region in front of the automobile backward in a relay manner based on a weight. An automobile at the back automatically obtains the real-time traffic information at the front. The automobile utilizes the characteristic of a great urban road network density to avoid low-speed and congested road sections in time, so that bearing capability of an urban road is improved and an urban road congestion problem is solved.

Description

Method for collecting and transmitting real-time traffic information in limited area in front of automobile

The invention relates to the collection, coding, road zoning and wireless communication mode planning of the vehicle speed, position and time information based on the satellite navigation vehicle terminal, the information exchange method without the control center between the vehicles and the automatic wireless broadcast of the real-time traffic information Technology such as relay transmission. Background technique

Automobile civilization is an irresistible direction for the development of human society. The smooth flow of traffic is the constant goal pursued by people. Technological advances in areas such as satellite navigation, intelligent transportation systems, and modern communications have laid the foundation for people to achieve smooth traffic.

For the driver of the car, driving safety is a top priority. At present, the technical development direction of the Internet of Vehicles is insufficient for the driver. It distracts the driver and creates a safety hazard. Fully automatic, intelligent transportation information for drivers is the development direction.

The real-time traffic information has high timeliness and large amount of information. The commonality of the methods for providing real-time traffic information in the prior art is that the information is first concentrated and distributed. The disadvantage is that the radio frequency resources are large in occupation, low in economy, and difficult to implement. .

For a long time now and in the future, traffic congestion problems mainly occur in cities. Urban roads have the characteristics of high density and many intersections. If vehicles can get real-time traffic information of limited road sections in front and avoid low-speed and congested road sections, it will greatly improve the carrying capacity of urban roads and people's travel efficiency. Summary of the invention

In order to overcome the above deficiencies of the prior art, the present invention provides a method for automatically obtaining real-time traffic information of roads in front of a limited area using a wireless broadcast communication method on a satellite navigation vehicle terminal. Its function is to enable the vehicle to obtain real-time traffic information of the limited area in front, and to use the characteristics of urban road network density to effectively avoid low-speed and congested road sections, greatly improve the carrying capacity of urban roads, and solve the problem of urban road congestion. The invention is based on an in-vehicle satellite navigation system and is composed of a wireless communication system, a road and communication mode planning system, a real-time traffic information collection and processing system, a database system and a real-time traffic information transmission system (see Fig. 1). Wireless communication system

The 802.11 standard is used as the basis of the wireless communication system, and the system hardware is used in a wireless broadcast manner. Use the four frequency points of 2412MHz, 2432MHz, 2452MHz, 2472MHz in the 2.4G public radio frequency band (represented by h, i, j, k respectively), in time division multiplexing (TDM) method (1, 2, 3, respectively) 4 denotes different time periods, each time period is 10 milliseconds) and 16 virtual frequency points are obtained (the frequency points are coded as: hl, il, jl, kl, h2, i 2, j 2, k2, h3, i 3, j 3 , k3, h4, i4, j 4, k4 ). The 802.11 chip receives all the information of all the logic points and sends information, and the chip is used to access the wireless network. Road and communication mode planning system

Based on the satellite navigation map, the frequent parking places of the intersections (level crossing, interchange, turntable, multi-crossing), T-shaped roads, toll stations, checkpoints, etc. are determined as nodes, and the roads are based on nodes as the starting point, east and south. 4 directions of west and north, each direction is divided into 4 sections (each section has a basic length of 100 meters). If the remainder is less than 50 meters, it will be merged into the last zone. If the remainder is greater than or equal to 50 meters, it will be divided into another zone. . Use A, B, C, and D to sequentially mark the partitions. The vehicles in the west, south, east, and north directions are made with 1, 2, 3, and 4, respectively, to generate westward Al, Bl, Cl, D1, northward A2. , B2, C2, D2, east A3, B3, C3, D3, south A4, B4, C4, D4 A total of 16 different codes representing 16 different zones. 16 radio communication frequency points are allocated to 16 areas, and frequency points of the same time period are allocated to areas in the same direction. The correspondence between road partitions and communication frequency points is shown in Table 1 (see Figure 2):

Table 1 (Road partition and communication frequency correspondence table)

If the total number of the two nodes is a multiple of 4 plus 1, determine the size of the last zone: when it is greater than or equal to 100 meters, divide it into two; otherwise, merge it with the last two zones, and then divide it into two two. The road segment between the two nodes is divided into the number of zones that are not (4N+1) to avoid communication interference.

For non-orthogonal, north-south roads, based on the direction of the road at the node, the direction is determined as the east-west or north-south direction, and the direction is determined to the next node.

When the distance between two nodes is less than 150 meters, the smaller nodes are ignored. The node size is based on the busyness of the road traffic. If the size cannot be distinguished, it is determined that the nodes in the west and north are large.

The complex road sections such as turntable intersections, multi-entry and multiple exits are converted into intersections for division, and the main traffic roads are prioritized (allocation of communication frequency points). For non-main traffic roads, the areas where the main traffic roads have communication interference (the interference distance is set at a straight line of 200 meters) are all marked as A5, and they are partitioned according to the above-mentioned partition rules without affecting the communication of the main traffic roads. For multi-layer, parallel (vertical distance less than 200 m) roads in the same direction, the busiest road sections are identified as the main traffic roads for division, and other areas with communication interference to the main traffic roads are marked as A5. A5 area does not allocate communication frequency Point, only receive wireless signals (see Figure 3).

Using the above rules, the navigation map is planned at one time, and the road and radio frequency planning database (hereinafter referred to as the planning database) is obtained for the application of the system. Real-time traffic information collection and processing system

A speed value is obtained every second from the satellite navigation system, and the speed is divided by 5 times to obtain an average value, which is used as the speed of the area where the vehicle is located. Simplify the speed information to 0, 1, 1, 5, 10, 15, 20, 30, 50, 75, and 90 (km/h). 11 levels above: 0. 1 is set to 0; greater than 0 is less than or equal to 1 5以下为1。 5 is less than 1. 5 is less than 2. 5 is greater than 2. 5 is less than 2. 5 is greater than 2; greater than 2. 5 is less than 7. 5 is set to 5; greater than 7. 5 is less than 12. 5 is set to 10; 5为为15。 More than 17. 5 is greater than 2. 5 is greater than 22. 5 is greater than 2; greater than 22. 5 is less than 37. 5 is set to 30; greater than 37. 5 is less than 62. 5 is set to 50; 5以下为为75. 5为为75. More than 87. 5 is set to 90 or more. The function of the above speed grading method is to increase the stability of the speed value to generate duration information of the speed with actual use value and to reduce the amount of information to be transmitted (hereinafter, the speed represents the speed level of the area in which the vehicle is located). database system

Limited area definition (see Figure 4): The roads included in the front and left and right R km radius of the car are used as finite areas (R initial value is 2 and minimum value is 1). The size of the finite area can be automatically adjusted according to the change in the amount of information and the transmission capacity. The rules are as follows: If the time period of the information transmission period is surplus and the remaining time is greater than 10% of the actual usage time, the R value is increased by one step unit; If it is less than one thousandth of the actual use time, the R value is reduced by one step unit; the R value step unit is 100 meters.

A planning database, a historical database, a vehicle information exchange database, and a real-time database are established. The real-time database is based on a limited area, and the size of the included area varies with the network density and communication capability.

Planning database: Generated once by the road and communication mode planning system for use by the system. Historical database: All the obtained speed data before 30 minutes is averaged and stored in 5 minutes. The time is based on the last time. Each group of information consists of 2 data of position and speed.

Dialogue database: Storage vehicle T1 (conversation) Information generated by the time period itself, information sent by other vehicles in the area, and vehicle information exchange control variables.

Real-time database: This includes the top-level database (real-time traffic information with a speed of 0 in the limited area (R+2) and a duration of more than 5 minutes. Each group of information consists of 2 locations of location and duration); The speed in the finite area (R+1) is 1 and the duration is large In 2 minutes of real-time traffic information, each group of information consists of two data: location and duration); external information database (traffic traffic in limited area (R), traffic temporary control, emergency avoidance information, severe congestion information on urban roads); Limited area database (storing the latest traffic information in each area of the limited area, each group of information consists of three pieces of data: position, speed, duration). Real-time traffic information transmission system

The system is cycled in three periods: T1 (conversation), T2 (transmission), and T3 (foreign). The time is 1. 5 seconds, 3 seconds, and 0.5 seconds. The total time is 5 seconds.

Set the T1 time vehicle information exchange control variable: K; Ki; G i ; J i ; Vi ; Qi ; S i ; G; J; V; Kj ; C; N; D; Tx; Ti.

The variable K is the random number maximum of the vehicle dialogue process; the variable Ki{ Ki = l, 2, 3 ... ( K-2 ),

(K-1), Κ } is the random number of the vehicle dialogue process; the variable Kj is the random number of other vehicles received; the variable V is the number of times the information is sent successfully during the recording of the vehicle conversation; the variable Vi is the record of the vehicle conversation The number of successful transmissions in the process; variable J is the number of times the information is transmitted during the conversation of the vehicle; the variable J i is the number of the transmission of the transmitting vehicle during the recording of the conversation; and the variable C is the number of times of information conflict during the recording of the vehicle conversation; The variable S i is a flag for recording whether the self information is correctly obtained by other vehicles in the vehicle conversation period (0 is no, 1 is YES); the variable G is the number of times the information in the vehicle conversation period is finally succeeded; the variable Gi is the recording vehicle conversation period. The number of the final success of the information; the variable D is used to determine whether there is only one car in the zone; the variable N is used to record the number of dialogue processes; the variable Tx is the T1 time period timer; the variable Ti is the timer of each dialog process; Q i is the vehicle information weight coefficient (the specific value is equal to the sum of the top-level database and the primary database data) The variable M2 is the success or failure information of the sender of the vehicle conversation process (Vi is greater than 0 indicates that the sender of the message is successful); the variable M1 is the vehicle conversation information (including Ki, speed, position, Qi, M2).

T1 time period running rules (see Figure 5):

The vehicle first classifies itself into a certain area according to the geographical location information, and then determines the communication frequency point that should be used according to the road and communication mode planning database information. Vehicle Initialization Conversation Database (K=30 in the information exchange control variable, N=D=G=V=J=C=Kj=Gi=S i=Ti=Tx=0) ₀ Tx timing starts. The unsuccessfully transmitted information vehicle generates a random number Ki (point A) of 1 to K. Ti timing begins. If no other vehicle sends a message in the vehicle listening area numbered Ki, then (10 ( Ki-Kj-C-1 ) +1 ) microseconds (the time units are not explicitly marked in the following subtle units) Initially, the information M1 is randomly sent from 0 to 8 and the self information is exchanged in the control variable J i=J=J+l. If the Ki number is the same, the person who has not received the letter will judge whether the number Ki+5 is less than K: If yes, re-number the process between (Ki+1) and K to participate in the process; otherwise, participate in the next process (hereinafter, use the variable) Represents the information exchange control variable). The vehicle receives the information. If the information is successful, let the variable Gi=G=G+l, Ji=J=J+K Vi=V=V+ Kj=Ki, C=0; for the M2 information, if Vi is greater than 0, Let Si=l in its variable; otherwise, let Ji=J=J+l, C=C+1, Gi=Vi=Ki=0 _{o in} its variable

The vehicle that completes the sending action determines whether the success of its own transmission is successful according to the information sent by the following vehicle: If it succeeds, let Gi=G=G+l, Vi=V=V+l, Si=l in its own variable; otherwise, Let Gi=Vi=Ki+0 in its own variable.

After the vehicle has no signal time greater than (10 (K-Kj-C) +1 ), it is judged that J is equal to 0 to end the dialogue period; otherwise, if the judgment (PI) N and G are both greater than 0, the vehicle numbered G1 Send the message M2. The vehicle is based on the M2 information, and the value of Vi is greater than 0, so that Si=l in the variable. The vehicle that finally completes the sending action judges according to the M2 information (P2) whether the self-delivery succeeds or not: If it succeeds, let Gi=G=G+l, Vi=V=V+l, Kj=Ki, Si=l in its own variable . All vehicles have a value of Si = 0 in Ki = Gi = Vi = 0. Determine whether G is greater than 10: If yes, end the session period; otherwise, add 1 to the N counter to determine whether N is greater than 2: If yes, end the session period; otherwise, determine if Ti is greater than Tl-Tx-1: If yes, end the session period; Otherwise, let V=J=C=Vi=Ji=Ki=Kj=Ti=0 _{o in the} vehicle variable return to point A.

(P2) Otherwise, let Gi=Vi=Ki=0 in its own variable. For all vehicles, the value of Si = 0 is Ki = Gi = Vi = 0. Determine whether G is greater than 10: If yes, end the session period; otherwise, add 1 to the N counter to determine whether N is greater than 2: If yes, end the session period; otherwise, determine if Ti is greater than Tl-Tx-1: If yes, end the session period; Otherwise, let V=J=C=Vi=Ji=Ki=Kj=Ti=0 _{o in the} vehicle variable return to point A.

(P1) Otherwise, it is judged whether (P3) J is greater than 1: If no, the D counter is incremented by 1 and then judged whether D is greater than 2: If yes, it is determined that there is only one car, the car is designated as the information transmitter, and the dialogue period is ended. ; Otherwise, return to point A.

(P3) Otherwise, judge (P4) whether V is greater than 1: If yes, the vehicle numbered VI sends the message M2, VI and other vehicles according to the M2 information for Vi greater than 0, so that Si=l in the variable. The vehicle that finally completes the sending action is judged according to the M2 information (P5). If the self-delivery succeeds: If it succeeds, let Gi=G=G+l, Vi=V=V+l, Kj=Ki, Si=l . All vehicles have a value of Si = 0 in Ki = Gi = Vi = 0. Determine whether G is greater than 10: If yes, end the session period; otherwise, add 1 to the N counter to determine whether N is greater than 2: If yes, end the session period; otherwise, determine if Ti is greater than Tl-Tx-1: If yes, end the session period; Otherwise, let V=J=C=Vi=Ji=Ki=Kj=Ti=0 _{o in the} vehicle variable return to point A.

(P5) Otherwise, let Gi=Vi=Ki+0 in its own variable. For all vehicles, the value of Si = 0 is Ki = Gi = Vi = 0. Determine whether G is greater than 10: If yes, end the session period; otherwise, add 1 to the N counter to determine whether N is greater than 2: If yes, end the session period; otherwise, determine if Ti is greater than Tl-Tx-1: If yes, end the session period; Otherwise, make the vehicle variable V=J=C=Vi=J i=Ki=Kj=Ti=0 _o returns to point A.

( P4 ) Otherwise, let G = 0 in all vehicle variables. In all variables where the vehicle makes S i = 0, K i = Gi = Vi = 0. Determine whether G is greater than 10: If yes, end the session period; otherwise, add 1 to the N counter to determine whether N is greater than 2: If yes, end the session period; otherwise, determine if Ti is greater than Tl-Tx-1: If yes, end the session period; Otherwise, let V=J=C=Vi=J i=Ki=Kj=Ti=0 _{o in the} vehicle variable return to point A.

During the dialogue process, due to the data difference between the Kj and C obtained by the vehicle, the vehicle is not synchronized. The backward vehicle immediately waits for the system to operate, and performs the prescribed action to join the normal dialogue process. The start of the next conversation process starts at a multiple of 5 microseconds for the T1 period.

After the multiple dialogue process, the information of other vehicles is obtained in the dialogue database of the vehicles in the area, and the information in all the vehicle dialogue databases in the area is completely the same. The highest speed value generated by the vehicle in the area is determined as the value of the area, and the value of the area is compared with the value of the previous time. If the values are equal, the duration of the previous time speed is increased by 5 seconds as the current speed. The duration value, otherwise the duration of its speed is set to 5 seconds. When the speed of this area is 0, if the speed of the rear adjacent area is greater than or equal to 10 (km/h) and the duration is longer than 1 minute, the speed of this area takes the rear value and its duration is set to 1 second. If the information weight (Qi) is the largest, the information transmission is the same. If the information weights are the same, the nearest one is the center of the local area. If the distance is equal, the lowest successful transmission number is obtained.

Set the vehicle T2 time period information transmission control variables Td, Ty, Th, Tw and ND, NY, and Li, and record four (top, first, outer and limited areas) database information transmission cumulative time and four database information remaining respectively. Quantity (do not repeat the count, the data margin is 0 means the information has been transmitted).

T2 time period running rules (see Figure 6):

The sending vehicle will prioritize the database information (top level, first level and limited area database information to generate the time closest to the first time, if the time is the same, the nearest to the area is preferred; the external database information priority is the emergency avoidance, urban road Serious congestion, traffic temporary control and traffic light information) transmission, while receiving information. Since the data is relayed, high-level information may be late, and the priority of the database information is re-queued after each set of information is transmitted. First transfer the top-level database information (the longest time is a quarter of the T2 period), then transfer the primary database information (the longest time is a quarter of the T2 period), and then transfer the external database information (the longest time is T2) One-ninth of the time period), the last limited database information is transmitted. Since the data is relay transmission, the database information of the upper level may be late, the database will be continuously updated, and when the information transmission of the next level database is completed, it will be transferred to the detection of the top database information. If the transmission time allocated by the top database is not used up and new The data is transferred to the top-level database information preferentially, otherwise it is transferred to the detection of the secondary database information and runs according to the above rules. Limited area database information is transmitted in 30 groups According to the post-transfer detection top-level database information and run with the above rules. The total time segmentation used for each database information transmission is cumulative.

Finite region R value adjustment rule: If ((T2-Td-Ty-Th-Tw) / (Td+Ty+Th+Tw)) is greater than 0.1, then R is increased by one step unit; if ((T2-Td) -Ty-Th-Tw) / (Td+Ty+Th+Tw) ) is less than 0.001, then R is reduced by one step unit; otherwise, the R value is not adjusted.

Running tasks in the T3 period: Receive traffic lights in the limited area (R), traffic temporary control, emergency avoidance information. Receive heavy traffic congestion on city roads. Adjust the R value. DRAWINGS

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a general frame view of the present invention.

2 is a schematic diagram of a road and communication mode planning system for a simple road in the present invention.

3 is a schematic diagram of a road and communication mode planning system for a complex road in the present invention.

Figure 4 is a schematic illustration of a limited area range in the present invention.

Fig. 5 is a schematic diagram showing the flow of the T1 (conversation) time period in the present invention.

Fig. 6 is a flow chart showing the operation flow of the T2 (transmission) period in the present invention.

Fig. 7 is a schematic view showing the operation of the vehicle in time to avoid the congested road section in the present invention. detailed description

The road and communication mode planning system will partition the roads on the satellite navigation map to realize the wireless communication frequency point conflict-free application and generate a planning database, and establish a historical database, a real-time database and a vehicle dialogue database. Taking the satellite navigation system time (Beijing time) as the standard, every 5 seconds is a cycle, and the vehicles transmit real-time traffic information to each other. The cycle is divided into Tl (1.5 seconds), Τ2 (3 seconds), Τ3 (0). . 5 seconds) 3 time slots.

T1 period: In the first step, let the information exchange control variable Κ=30, N=D=G=V=J=C=Kj=G i=S i=Ti=Tx=0. The second step is to generate real-time traffic information of the vehicle based on the satellite navigation system. In the third step, the vehicle classifies the vehicle into a certain area according to the planning database information, and determines its own communication frequency. In the fourth step, each district vehicle uses the communication frequency points of the district to talk to each other to exchange information, process and process real-time traffic information in the area, and determine the information transmitter (see Figure 5).

T2 period: The fifth step is to make the information transmission control variable Td=Ty=Th=Tw=ND=NY H= and =0. In the sixth step, each zone information transmitter sends real-time traffic information while receiving real-time traffic information from other information transmitters, and other vehicles receive real-time traffic information from the information transmitter as much as possible (see Figure 6).

T3 period: In the seventh step, the vehicle receives external information. In the eighth step, the vehicle adjusts the R value according to the time data required for information transmission in the T2 period: if ((T2-Td-Ty-Th-Tw) I (Td+Ty+Th+Tw)) is greater than 0.1, then R increases a step unit; if ((T2-Td-Ty-Th-Tw) / (Td+Ty+Th+Tw) ) is less than 0. 001 then R is reduced by one step unit; otherwise, the R value is not adjusted. In the ninth step, the task is transferred to the T1 time period.

Through the above steps, the vehicle can obtain real-time traffic information of the limited area in the front within 5 seconds. The satellite navigation system is responsible for displaying and using real-time traffic information. Drivers and satellite navigation systems can timely avoid congestion and low-speed sections based on real-time traffic information. For example, a vehicle at point C of a city road must pass point A to point B (see Figure 7). If congestion occurs at point A, the vehicle continuously enters the AC section, and congestion will occur immediately at point C, which will quickly cause Cl and C2 to occur. Congestion, causing large-scale traffic congestion. The invention provides real-time traffic information in a limited area in front of the vehicle, and the vehicle at point C finds that there is congestion at point A, and the other two routes can be selected (C-C1 - A1 - B1 - B; C - C2 - A2 - B2 - B) ) Arrived at point B, thus avoiding congestion and improving the capacity of urban roads.

Claims

Rights request

A method for collecting and transmitting real-time traffic information in a limited area in front of a vehicle, characterized in that: based on the in-vehicle satellite navigation system, wireless broadcast communication is used for information transmission, the road is divided into zones and communication is assigned thereto. Resources, vehicles in the area collect real-time traffic information in the area, exchange information with each other, determine the information transmitter and transmit the real-time traffic information in the limited area ahead to the rear by weight; the invention includes wireless communication system, road and communication mode planning System, real-time traffic information collection system, database system and real-time traffic information transmission system.

2. The method according to claim 1, wherein: the wireless communication system uses the 802.11 standard as a basis of the wireless communication system, and uses the system hardware in a wireless broadcast mode, using a 24.4G public radio frequency band of 2412 MHz, 2432 MHz. , 2452MHz, 2472MHz four frequency points, get 16 virtual frequency points by time division multiplexing (TDM) method, use 802.11 chip to receive all the information of all logic frequency points and send information, the chip is used to access the wireless network.

3. The method according to claim 1, wherein: the road and communication mode planning system is based on an in-vehicle satellite navigation map, and the road is based on nodes (intersection center points) as east, south, west, Four directions of northward direction, each direction is divided into four sections (each section has a basic length of 100 meters), and 16 different zones are generated and assigned communication frequency points, and the frequency points of the same time period are allocated to the same The direction of the zone; the length of the zone is divided into two sections (4N+1) to avoid communication interference; the complex sections are partitioned and allocated frequency to ensure normal communication of the main road The road partition and frequency allocation information is generated into a road and radio frequency planning database (hereinafter referred to as a planning database).

4. The method according to claim 1, wherein: the real-time traffic information collection and processing system acquires a speed value from the satellite navigation system every second, and adds the average value of 5 speeds divided by 5 as the vehicle location. The speed of the area, the speed information of the area where the vehicle is located is simplified to 0, 1, 2, 5, 10, 15, 20, 30, 50, 75 and 90 (km / h) above 11 levels, its role is to increase The stability of its value is used to generate duration information of the speed grade of the area in which the vehicle has actual use value and to reduce the amount of information that needs to be transmitted (hereinafter, the speed represents the speed grade of the area in which the vehicle is located).

5. The method according to claim 1, wherein: the database system comprises a planning database, a historical database, a vehicle information exchange database, and a real-time database; the real-time database includes a limited area database (in front of the car, left and right R (R) The value is 2 and the minimum value is 1) the latest traffic information of the roads included in the radius of the kilometer), the top-level database (real-time traffic information with a speed of 0 in the front of the car (R+2) and a duration of more than 5 minutes), Primary database (before the car Square (R+l) Real-time traffic information with a speed of 1 in a kilometer radius and a duration of more than 2 minutes), external information database (traffic lights within R km radius in front of the car, temporary traffic control, emergency avoidance information, severe congestion on urban roads) Information); each group of information in the limited area database consists of three pieces of data: position, speed, and duration; each group of information in the top-level database and the primary database consists of 1 position and duration; the size of the limited area can be automatically adjusted. The rule is: If the information transmission time is rich, and the remaining time is greater than ten percent of the actual usage time, the R value is increased by one step unit; if the remaining time is less than one thousandth of the actual usage time, the R value is decreased by one step. Unit; R value step unit is 100 meters.

6. The method according to claim 1, wherein: the real-time traffic information transmission system is divided into three periods of T1 (1.5 seconds), T2 (3 seconds), and T3 (0.5 seconds). The planning database supports cyclic operation in the form of wireless broadcast communication; the task of the T1 period is that the vehicles in the area talk to each other to exchange information, determine the speed of the area and the information transmitter; the task of the T2 period is that the information transmitter of each area will have the top database, The level database, the external database and the limited area database information are transmitted outwards in turn, all vehicles receive information from other vehicles; the task of the T3 period is that all vehicles receive external information, and the limited area is adjusted according to the T2 period operation data and the rules in claim 5. size.

7. The method according to claim 6, wherein: in the T1 period, the information is randomly generated in each area in each session, and the vehicle randomly generates a number from 1 to 30, and the number is based on the time of sending, random. Send each random number, speed, position, and information weight coefficient between 0 and 8 microseconds (the information weight coefficient value is equal to the sum of the top-level database and the primary database data), and the success or failure information of the sender of the dialogue process. Vehicles receive information from other vehicles and determine whether their own transmission is successful and determine whether the information they receive is recognized by other vehicles. The information is not successfully sent. The vehicle regenerates the random number from 1 to 30 for the next dialogue process, multiple conversations. After the process, the vehicle obtains other vehicle information and makes the information of all the vehicles mutually agree; taking the highest speed of the vehicle as the speed of the area, determining the duration of the speed of the area according to the speed of the previous time and its duration in the area; When the speed of this area is 0, if the speed of the rear adjacent area is greater than 10 (km/h) and The duration is greater than 1 minute, the speed of the zone is taken as the rear value, and the duration is set to 1 second; the one with the largest information weight coefficient is used as the information transmitter of the zone (if the information weight is the same, the nearest is the center of the zone; if the distance is If they are equal, the one with the lowest successful transmission number).

8. The method according to claim 6, wherein: the database information of the T2 period is according to a priority level (top level, first level and limited area database information to generate time is the closest, if the time is the same, to the distance area) Most recent priority; external database information prioritization is emergency avoidance, severe urban road congestion, traffic temporary control, traffic light information) transmission, information transmitters receive information while sending information, because high-level information may be late, each group issued Re-queue the information priority level after the information; first transmit the top-level database information (when the usage time is T2) One-fourth of the segment), the second-level database information is transmitted (the usage time is one quarter of the T2 period), the external database information is transmitted again (the usage time is one-ninth of the T2 period), and the limited area database is finally transmitted. Information; Since the upper-level database information may be late, the next-level database information transfer is transferred to the detection top-level database information. If the top-level database allocation transmission time is not used up and new data is available, the top-level database information is preferentially transmitted. Otherwise, it transfers to the detection sub-level database information and runs according to the above rules; the limited area database information is transferred to the detection top-level database information after the transmission of 30 sets of data and runs according to the above rules.

9. The method according to claim 6, wherein: all vehicles in the T3 period receive a limited area traffic light, traffic temporary control, emergency avoidance information, urban road serious congestion information, and implement traffic management department management of the system vehicle, Scheduling and command functions.