JP3528720B2 - Route guidance information providing apparatus and route guidance information providing system - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a route guidance information providing device, and a route guidance information providing system having a plurality of communication terminals for receiving route guidance information and a route guidance information providing device.

[0002]

2. Description of the Related Art As a route guidance information providing system of this type, there is a vehicle navigation system in which route guidance information is provided from an information center to an in-vehicle device. In this system, route guidance information is provided for each constant section length (= information valid section length) of the guide route. At the predetermined timing before the end of the travel for the information valid section length,
The following route guidance information is provided to the in-vehicle device. That is, in the conventional system, the transmission timing of the route guidance information is determined by the travel situation of the vehicle-mounted device.

[0003]

However, in such a system, since the transmission timing of information is determined by the travel situation of the vehicle-mounted device, the route guidance information is provided to a large number of vehicle-mounted devices at the same timing. In order to deal with this, the processing capacity of the information center must be greatly increased compared to the average processing time, which increases the scale of the information center and the consumption of the information center. There has been the problem of increased power and installation costs.

[0004]

In view of the above problems, the present invention adjusts and determines each information effective section length of route guidance information to be transmitted to a plurality of communication terminals. It is possible to reduce the processing load on the information center by distributing the timing of providing the next route guidance information of the machine.

Further, according to the present invention, the transmission timings of the route guidance information to be transmitted to a plurality of communication terminals are adjusted and determined among them, and the route guidance information is provided at this timing. The timing of providing information can be dispersed to reduce the processing load on the information center.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention in which the route guidance information providing system according to the present invention is applied to a vehicle navigation system will be described below with reference to the drawings. FIG. 1 shows a conceptual diagram of a vehicle navigation system according to this embodiment, and FIG. 2 shows a block diagram of a schematic system configuration of the vehicle navigation system.

The vehicular navigation system 10 has a route guidance information providing device such as an information center 20 and a communication terminal such as an in-vehicle device 30. The information center 20 can provide route guidance information to a plurality of vehicle-mounted devices 30.

The information center 20 adjusts the information effective section lengths of the route guidance information to be transmitted to the plurality of vehicle-mounted devices 30 to determine the information effective section lengths, and the information effective section length determining unit 22. A route guidance information generation unit 21 that generates route guidance information of a section length, a storage unit 23 that stores various information such as map information, and route guidance information and other information between the vehicle-mounted device 30. And a wireless communication unit 24 for communicating information.

Further, the vehicle-mounted device 30 has a wireless communication unit 35 for communicating route guidance information and other information with the information center 20 or another vehicle-mounted device 30, and route guidance information received by the wireless communication unit 35. Is controlled by the route guidance control unit 31, which controls the implementation of the route guidance based on the above, the control unit 36 including the route guidance control unit 31, and the route guidance control unit 31.
A display unit 33 that provides display guidance of a route and a voicing unit 34 that is also controlled by the route guidance control unit 31 and that provides voice guidance of the route.
And a storage unit 32 that stores various kinds of information such as map information. Hereinafter, the determination of the information effective section length and the generation and provision of the route guidance information based on this determination will be described in the present embodiment.

<Embodiment 1.1 Determination of Information Valid Section Length According to Moving Speed> FIG. 3 is a flowchart showing determination of the information valid section length and provision of route guidance information according to the present embodiment. When the route guidance information generation unit 21 generates route guidance information for a plurality of vehicle-mounted devices 30 (S101), it compares the load of the information center 20 with a default value n (S102), and when the load is greater than the default value n. First, a plurality of vehicle-mounted devices 30 that generate route guidance information
For each moving speed, for example, the section average moving speed Vx between two predetermined points is acquired (S103), and the moving average speed Vave. Is calculated (S104). Next, the average moving speed Vx and the average moving speed Vave. Based on the following equation (1), the information effective section length L1 (i) of the route guidance information transmitted to each vehicle-mounted device 30 is calculated (S105).

## EQU00001 ## L1 (i) =. Alpha..Vave. / Vx (i) · Ls (1) (α: variation coefficient, Ls: reference section length, i: vehicle-mounted device ID) From this formula, the information effective section length L1 (i) is the section average moving speed Vx. The smaller is, the longer the value is set. That is,
If the travel speed is small, that is, the travel time of the information valid section is long, the travel time is set to be long by giving a longer information valid section length, and the travel speed is large and the travel time of the information valid section is short. In contrast, by giving a shorter information valid section length and setting a shorter travel time, it is possible to further spread the transmission timing. Next, the route guidance information generation unit 21 generates route guidance information of the information valid section length for each vehicle-mounted device 30 determined in step S105 (S106). If the load on the information center 20 is lower than the predetermined value n in step S102, the information valid section length of each route guidance information is set to the reference section length Ls (S107), and the route guidance information is generated to be mounted on each vehicle. Provided to the machine 30 (S10
8). In this way, the information effective section length of each in-vehicle device 30 is
By adjusting and determining different lengths according to the respective moving speeds, it is possible to disperse the transmission timings of the next route guidance information. Further, by setting the information effective section length in inverse proportion to the moving speed, it is possible to further widely disperse the transmission timing of the route guidance information.

<Embodiment 1.2 Determination of Information Valid Section Length According to Position of In-Vehicle Unit> FIG. 4 is a flowchart showing determination of the information valid section length and provision of route guidance information according to the present embodiment. Route guidance information generation unit 21
Compares the load of the information center 20 with a default value n (S112) when generating route guidance information for a plurality of vehicle-mounted devices 30 (S112). The plurality of vehicle-mounted devices 30 are grouped for each vehicle-mounted device 30 whose current position is close (S113). Next, the distance Lx of the other vehicle-mounted devices A and B with respect to the last vehicle-mounted device C in these groups is calculated (S114). The distance Lx to the rearmost in-vehicle device C in this group
Based on the following equation (2), the information effective section length L2
(I) is determined (S115).

[Equation 2] L2 (i) = (α · Lx (i) +1) · Ls (2) (where, α: variation coefficient, Ls: reference section length, i: vehicle-mounted device ID) The information effective section length is set to a longer value as the distance Lx is larger. Next, the route guidance information generation unit 21
Generates route guidance information of the information valid section length for each vehicle-mounted device 30 determined in step S115 (S11).
6). If the load on the information center 20 is lower than the predetermined value n in step S112, the information valid section length of each route guidance information is set to the reference section length Ls (S11).
7), route guidance information is generated and provided to each in-vehicle device 30 (S118). In this way, by setting the information effective section length of each vehicle-mounted device 30 to a different length according to the position of the vehicle-mounted device 30, it is possible to disperse the transmission timing of these next route guidance information.

<Embodiment 1.3 Determination of Information Effective Section Length Using Random Number> FIG. 5 is a flowchart showing determination of the information effective section length and provision of route guidance information according to the present embodiment. When generating route guidance information for a plurality of vehicle-mounted devices 30 (S121), the route guidance information generation unit 21 compares the load of the information center 20 with a default value n (S122), and the load is lower than the default value n. If larger,
The information valid section length of each vehicle-mounted device 30 is determined using a random number (S123). That is, the information valid section length of each in-vehicle device 30 is determined to be different length using random numbers. Next, the route guidance information generation unit 21 generates the route guidance information of the information effective section length for each in-vehicle device 30 determined in step S123 and provides it to the in-vehicle device 30 (S12).
4). If the load on the information center 20 is lower than the predetermined value n in step S122, the information valid section length of each route guidance information is set to the reference section length Ls (S12).
5), route guidance information is generated and provided to each vehicle-mounted device 30 (S126). In this way, by determining the information effective section length of each vehicle-mounted device 30 by using the random number, the transmission timing of the next route guidance information can be dispersed.

Next, a second embodiment of the present invention in which the route guidance information providing system according to the present invention is applied to a vehicle navigation system will be described with reference to the drawings. FIG. 6 is a block diagram showing a schematic configuration of the vehicle navigation system 10 of the present embodiment, and FIG.
FIG. 8 is a flow chart of the information center side showing the adjustment of the transmission timing of the present embodiment, FIG. 8 shows an example of the adjustment of the transmission timing of a plurality of vehicle-mounted devices, and FIG. FIG. 10 shows a flow chart on the machine side, FIG. 10 shows a communication sequence in the case where transmission timings do not overlap, and FIG. 11 shows a communication sequence in the case where transmission timings overlap.

In the present embodiment, the control unit 25 has a transmission timing determining unit that determines transmission timings of route guidance information to be transmitted to a plurality of communication terminals by adjusting them. Hereinafter, adjustment of the transmission timing in this embodiment will be described.

For example, when the route guidance information is generated in response to the route guidance information request signal from the vehicle-mounted device 30 (S20).
1), the information center 20 acquires the movement status information of the vehicle-mounted device 30 (S202). This movement status information includes the current position of the vehicle-mounted device 30, the traveling direction, the moving speed, and the like.
Then, the route guidance information is generated and provided to the vehicle-mounted device 30 (S203). Then, the traffic condition information regarding the congestion of the guide route is acquired (S204), and the next transmission time of the route guide information to each in-vehicle device 30 is predicted in consideration of the acquired traffic condition information (S205). Storage unit 23
The route guidance information transmission predicted time table stored in is updated (S206). Then, it is checked whether or not the route guidance information transmission predicted times overlap (S207), and if there is any overlap, a plurality of in-vehicle devices including the in-vehicle device 30 in which the predicted transmission times overlap so as to eliminate this duplication. The transmission timing is adjusted for 30 (S208). FIG. 8 shows an example of adjusting the transmission timing. In this example, the predicted route guidance information transmission times of the four vehicle-mounted devices (A, B, C, D) are C, (B and D), and A in this order from the earliest time, that is, The route guidance information transmission predicted times of the vehicle-mounted devices B and D overlap (FIG. 8A). At this time, the transmission timing determination unit 26 shifts the time of the vehicle-mounted device C to an earlier side, and changes the time of the vehicle-mounted device D to a time later than the vehicle-mounted device C and earlier than the vehicle-mounted device B, for example. As a result, non-overlapping transmission timings are arranged in the order of C, D, B, A from the earliest time (FIG. 8B). Alternatively, it is also possible to shift the time of the vehicle-mounted device D to the side earlier than the vehicle-mounted device C, thereby forming non-overlapping transmission timings in the order of D, C, B, and A from the earliest time (FIG. 8).
(C)). When changing the time, it is desirable to change this to an earlier time. Further, in the case of this example, the time may be changed for the vehicle-mounted device B, and the time may be changed for the other vehicle-mounted devices. On the other hand, the information center 20 has the above-described steps S201 to S208.
Independently of, the steps S211 to S215 check whether or not the transmission time is changed as a result of the adjustment of the transmission time. This state is shown in FIG. First, the information center 20 acquires the current time (S211), acquires the route guidance information transmission predicted time of each vehicle-mounted device 30 from the route guidance information transmission predicted time table (S212), and calculates the route guidance information transmission predicted time. When the transmission time is changed, it is checked whether or not the transmission time is changed, for example, a predetermined time (for example, 1 minute) (S213), and if the transmission time is changed, the corresponding in-vehicle device 30 is checked. It is determined that it is necessary to request the transmission of the route guidance information (S214), and a request signal for notifying that the request to obtain the route guidance information is required is transmitted to the in-vehicle device 30 (S2).
15).

When the request signal for obtaining the route guidance information in step S215 is received from the information center 20 (S221), the in-vehicle device 30 side obtains the remaining information valid section length (information remaining section length) ( (S222), the information remaining section length is compared with the predetermined section length (S223), and if it is smaller than the predetermined section length, the information center 20 is requested to transmit the route guidance information (S224). By this comparison, the transmission timing change is canceled when the information valid section is sufficiently left, and the occurrence of useless information communication is suppressed. Then, the route guidance information is received (S225),
Upon completion of this reception (S226), route guidance based on this route guidance information is started (S227).

FIG. 10 is a diagram showing a communication sequence between the information center 20 and the vehicle-mounted device 30 in the case where duplication of transmission times of route guidance information is not predicted. At this time, information center 2
On the 0 side, duplicate transmission times are not predicted, so
Step S208 is not executed. Incidentally, steps S211 to S2
Regarding step 15, independently of steps S201 to S208,
Since it is a routine for checking whether or not the transmission time is changed in steps S201 to S208, it is not shown in this communication sequence diagram (FIG. 10). The vehicle-mounted device 30 transmits a request signal for transmission of route guidance information and a signal a indicating the movement status of the vehicle-mounted device 30 (S224).
The information center 20 receives this signal a (S201,
S202). The information center 20 accordingly responds to the in-vehicle device 3
The route guidance information b is transmitted to 0 (S203), and the vehicle-mounted device 30 receives this route guidance information b (S225).
This sequence is repeated thereafter.

On the other hand, FIG. 11 shows the information center 20 and the on-vehicle device 30 when the transmission times of the route guidance information are predicted to overlap.
It is a figure which shows the communication sequence with. When the overlap is predicted, the information center 20 transmits a request signal c for obtaining route guidance information (S215), and the vehicle-mounted device 30 receives this (S221). In response to this, the vehicle-mounted device 30 transmits a request signal for transmitting the route guidance information and the signal a indicating the movement status of the vehicle-mounted device 30 to the information center 20 (S22).
4). The information center 20 receives the signal a (S20
2) The route guidance information b is transmitted to the vehicle-mounted device 30 (S203).

As described above, in this embodiment, the overlap of the transmission times of the route guidance information for a plurality of vehicle-mounted devices is predicted, and these transmission timings are adjusted based on this prediction, so that the load on the information center is reduced. be able to. Also,
By adjusting the transmission timing only when duplication is predicted, the load on the information center is reduced and the communication time and cost are saved.

The present invention is not limited to the above embodiment. For example, the information valid section length determination unit (3 in FIG.
7) may be provided on the in-vehicle device side. In this case, the information valid section length is adjusted and determined by the information valid section length determination unit 37 based on various information, and the information of the determined information valid section length is sent to the route guidance information generation unit 21. Based on the route guidance information is generated. Further, the adjustment of the information effective section length may be performed based on an index other than the moving speed or the position. Further, the calculation of the information valid section length is not limited to the above-mentioned calculation formula. Further, the transmission timing determination unit (38 in FIG. 6) may be provided on the in-vehicle device side. In this case, the transmission timing is adjusted and determined by the transmission timing determination unit 38 based on various information, the determined transmission timing is sent to the route guidance information generation unit 21, and the route guidance information is transmitted at this transmission timing. It
Further, when adjusting the transmission timing, in the above-described second embodiment, the information center transmits a route guidance information acquisition request to the in-vehicle device, but this is transmitted to the in-vehicle device due to the arrival of the predicted time. You may make it transmit route guidance information directly. Then, in the first or second embodiment, the adjustment of the information effective section length or the adjustment of the transmission timing may be performed for a plurality of vehicle-mounted devices that are communicating with the same base station. As a result, wireless congestion can be further reduced.

[0021]

As described above, according to the present invention,
By adjusting the information effective section length of route guidance information for multiple in-vehicle devices or adjusting the timing of route guidance information transmission, the timing of route guidance information transmission can be dispersed and the processing load on the information center can be reduced. The expansion of the scale of the center is prevented, and the power consumption and installation cost of the information center are reduced.

[Brief description of drawings]

FIG. 1 is a conceptual diagram of a vehicle navigation system according to a first embodiment of the present invention.

FIG. 2 is a block diagram showing a schematic system configuration of a vehicle navigation system according to the first embodiment of the present invention.

FIG. 3 is a flowchart showing determination of an effective information section length and provision of route guidance information according to the first embodiment of the present invention.

FIG. 4 is a flowchart showing determination of an information valid section length and provision of route guidance information according to the embodiment 1.2 of the present invention.

FIG. 5 is a flowchart showing determination of an effective information section length and provision of route guidance information according to the embodiment 1.3 of the present invention.

FIG. 6 is a block diagram showing a schematic system configuration of a vehicle navigation system according to a second embodiment of the present invention.

FIG. 7 is a flowchart on the information center side showing adjustment of transmission timing in the vehicle navigation system according to the second embodiment of the present invention.

FIG. 8 is an explanatory diagram showing an example of transmission timing adjustment in the vehicle navigation system according to the second embodiment of the present invention.

FIG. 9 is a flowchart on the in-vehicle device side showing adjustment of transmission timing in the vehicle navigation system according to the second embodiment of the present invention.

FIG. 10 is a diagram showing a communication sequence in the vehicle navigation system according to the second embodiment of the present invention when transmission timings do not overlap.

FIG. 11 is a diagram showing a communication sequence in the case where there are overlapping transmission timings in the vehicle navigation system according to the second embodiment of the present invention.

[Explanation of symbols]

10 vehicle navigation system (route guidance information providing system), 20 information center (route guidance information providing device), 21 route guidance information generation unit, 22,37 information effective section length determination unit, 24,35 wireless communication unit, 26, 38
Transmission timing determination unit, 30 In-vehicle device (communication terminal).

Continuation of front page (51) Int.Cl. ⁷ identification code FI H04B 7/26 H04B 7/26 H (56) References JP-A-10-103933 (JP, A) JP-A-2000-28371 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) G01C 21/00-21/36 G08G 1/00-9/02 G09B 23/00-29/14 H04B 7/26

Claims (7)

(57) [Claims] 1. A route guidance information providing device for transmitting route guidance information to a communication terminal, wherein information valid section lengths of route guidance information to be transmitted to a plurality of communication terminals are adjusted among them to determine information validity. Route guidance information having section length determination means, route guidance information generation means for generating route guidance information of the determined information valid section length, and communication means for transmitting the generated route guidance information to a communication terminal. Providing device. 2. The route guidance information providing device according to claim 1, wherein the information valid section length determining means determines the information valid section length based on a moving speed of each communication terminal. 3. The route guidance information providing device according to claim 1, wherein the information valid section length determining means determines the information valid section length based on the position of each communication terminal. 4. The route guidance information providing device according to claim 1, wherein the information valid section length determining means determines the information valid section length by using a random number. 5. In a route guidance information providing device for transmitting route guidance information to a communication terminal, a transmission timing determination for determining the respective transmission timings of the route guidance information to be transmitted to a plurality of communication terminals by adjusting between them. A route guidance information providing device comprising: a unit; and a communication unit that transmits the route guidance information to each communication terminal at the determined transmission timing. 6. An information valid section length determining means for determining each information valid section length of route guidance information to be transmitted to a plurality of communication terminals by adjusting the information valid section length between them, and route guidance of the determined information valid section length. Route guidance information generating means for generating information,
A route guidance information providing system including: a route guidance providing device including: a communication unit that transmits the generated route guidance information to a communication terminal; and a plurality of communication terminals that receive the route guidance information and perform route guidance. . 7. A transmission timing determining means for determining transmission timings of route guidance information to be transmitted to a plurality of communication terminals by adjusting the transmission timings, and the route guidance information at each of the determined transmission timings. A route guidance information providing system including: a route guidance information providing device including a communication unit that transmits to a communication terminal; and a plurality of communication terminals that receive route guidance information and perform route guidance at the determined transmission timing.