JP3797268B2 - Car navigation system - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present inventionnavigationRelates to the device.
[0002]
[Background Art and Problems to be Solved by the Invention]
Conventionally, in an in-vehicle navigation device, a route from a departure point to a destination is searched, a section distance to a guidance intersection where a next right / left turn should be guided along the route, and a direction to be guided at the guidance intersection (that is, And the direction in which the vehicle should turn according to the route) is displayed, and the section distance is updated according to the travel of the vehicle. Hereinafter, the direction to be guided at the guidance intersection is referred to as a guidance direction.
[0003]
  In such an in-vehicle navigation device, it is necessary to acquire position information such as a departure place.ButYes, complicated processing is required when obtaining position information based on GPS signals received from GPS (Global Positioning System) satellites.
[0004]
Therefore, the present inventors have made a communication network that simplifies the processing of the in-vehicle navigation device by combining the in-vehicle navigation device and a communication navigation device that performs position calculation by a server of the mobile communication network. The system was considered as follows.
[0005]
That is, in the communication network system, when the occupant sets a destination for the operation unit of the in-vehicle navigation device, the in-vehicle navigation device uses the destination information indicating the destination and each GPS signal (or the positioning received from the base station). Information) is transmitted to the server via the base station of the mobile communication network. Then, this server searches for a route based on the destination information and each GPS signal (or positioning information), and the section distance to the next guidance intersection to be guided in this route and the guidance at the guidance intersection. The direction is calculated, and the section distance and the guidance direction are transmitted to the in-vehicle navigation device via the base station.
[0006]
After that, when the in-vehicle navigation device receives the transmitted section distance and the guidance direction, based on each section distance and each guidance direction, the guidance direction at the next guidance intersection and the section distance to the next guidance intersection Is displayed. In addition to this, each GPS signal (or positioning information received from the base station) is transmitted to the server via the base station at regular intervals, and current location information is transmitted to the server based on each GPS signal (or positioning information). Is calculated for each transmission, and the current location information is transmitted from the server via the base station for each calculation.
[0007]
Here, when receiving the current location information, the in-vehicle navigation device updates the display distance to the next guidance intersection based on the current location information every time the information is received. As a result, it was considered that the display distance to the next guidance intersection can be sequentially updated according to the travel distance of the vehicle, and the passengers can be better guided to the next guidance intersection.
[0008]
However, in order to update the display distance to the next guidance intersection, it is necessary to transmit each GPS signal to the server at regular intervals and acquire current location information from the server for each transmission. Communication costs are incurred. On the other hand, instead of acquiring the current location information from the server, it may be possible to measure the travel distance of the vehicle based on the rotation of the wheels and update the display distance to the next guidance intersection based on the travel distance. .
[0009]
In this case, although communication costs can be reduced, there is a possibility that the mileage cannot be measured accurately depending on the running state of the vehicle and road conditions, and the actual distance to the next guidance intersection and the display distance are greatly separated. Thus, there is a possibility that the passenger cannot be well guided to the next guidance intersection. Therefore, when the vehicle arrives before the guidance intersection, it is considered that it is necessary to acquire the current location information with high accuracy and update the display distance to the next guidance intersection based on this location information.
[0010]
  In view of the above points, the present invention reduces the communication cost and enables accurate current location information to be acquired when the vehicle reaches before the intersection.navigationAn object is to provide an apparatus.
[0011]
[Means for Solving the Problems]
  In order to achieve the above object, according to the present invention, in the first aspect of the present invention, an in-vehicle that can wirelessly communicate with a base station of a mobile communication networknavigationA receiving means (S2) for receiving positioning information necessary for calculating the vehicle position, a setting means (S1) for setting a destination, and the set destination and received positioning information. To the base stationMake a route search request andMobile communication network based on the received positioning information and destinationCalculate the current location of the vehicle and from the current location of the vehicleInformation on the distance to the next intersection that should be turned along the route searched for the route to the destination.And direction information to turn at the intersectionCalculated by the mobile communication network, and this calculated distance informationAnd direction informationRoute information acquisition means (S3, S4) for acquiring the vehicle via the base station, measurement means (19b) for measuring the travel distance of the vehicle,Display means (16) and display control means (S7) for displaying the acquired distance information and direction information on the display means and updating the distance information displayed on the display means based on the measured travel distance )When,Measured mileage andGetBased on the distance informationSelfTravel distance determination means (S9) for determining whether or not the distance from the vehicle position to the next intersection to bend is less than a predetermined distance, and the distance from the vehicle position to the next intersection to be bent is less than the predetermined distance When the travel distance determination means determines that, the received location information is transmitted to the base station, and based on the transmitted location information, the mobile communication network calculates the current location information of the vehicle, and the calculated current location Current location information acquisition means (S11, S11b) for acquiring information via a base station;Display update means (S12) for updating the distance information displayed on the display means based on the acquired current location information;It is characterized by having.
[0012]
  Here, in order to reliably guide the occupant to the next intersection to be guided according to the route, it is necessary to notify the occupant of the exact distance to the intersection when the vehicle reaches before the intersection. . Along with this, in-vehiclenavigationThe device needs to obtain accurate current location information when the vehicle reaches before the intersection.
[0013]
  For example, in-vehiclenavigationBy acquiring current location information from the mobile communication network at regular intervals, the device can inevitably acquire accurate current location information from the mobile communication network when the vehicle reaches the intersection. However, excessive communication costs are required.
[0014]
  On the other hand, according to the first aspect of the present invention, when the distance from the own vehicle position to the intersection is less than the predetermined distance, the current location information acquisition means calculates the current location information of the own vehicle through the mobile communication network. This current location information can be acquired via the base station. Thus, the current location information can be acquired from the mobile communication network only when the distance from the vehicle position to the intersection is less than the predetermined distance. Therefore, accurate current location information can be acquired when the vehicle arrives before the intersection while reducing communication costs.According to the first aspect of the present invention, since the display update means (S12) updates the distance information displayed on the display means based on the acquired current location information, the vehicle is at the intersection. When reaching the near side, accurate distance information can be notified.
[0015]
  Here, like the invention according to claim 2,The display control means preferably updates the distance information displayed on the display means based on the measured travel distance from the time when the route search request is made.
[0017]
  Also,As in the invention according to claim 3, the detection means (19a) for detecting that the own vehicle is bent at the intersection is used.Each time the detection circuit detects that the vehicle is bent at the intersection, the route information acquisition means may acquire distance information and direction information to the next intersection to be bent via the base station. it can.
[0021]
  Also,The display control meansOn the basis ofDisplayedHaveUpdate the distance informationIfDrove for a long time or long distanceWhenThere is a possibility that the distance information includes an error.
[0022]
  Therefore, the claim4Invention described inThenWhenever the time determination means (S92) for determining whether or not a certain period has elapsed and the time determination means for determining that a certain period or more has elapsed, the received positioning information is transmitted to the base station. Current location information acquisition means (S10b, S10c) for calculating the current location information of the vehicle based on the obtained positioning information and acquiring the calculated current location information via the base station, and the acquired current location information On the basis of the,Display meansDisplayedHaveDisplay updating means (10d) for updating the distance informationis doing.
[0023]
Thus, even if the distance information displayed by the display means includes an error, it can be corrected correctly.
[0024]
  Also, Claims5As in the invention described in the above, based on the measured travel distance, travel determination means (S93) for determining whether or not the host vehicle has traveled more than a certain distance, and travel determination that the host vehicle has traveled more than a certain distance Each time the means determines, the received positioning information is transmitted to the base station, and based on the transmitted positioning information, the current location information of the vehicle is calculated in the mobile communication network, and the calculated current location information is sent to the base station. Based on the current location information acquisition means (S10b, S10c) acquired via the acquired current location information,Display meansDisplayedHaveDisplay updating means (10d) for updating the distance information,You may comprise so that it may have.
[0025]
In Japanese Patent Laid-Open No. 2001-84493, it has been proposed to reduce the communication cost by downloading the map data of the belt-like area along the route from the gazette mobile communication network. There is no description of anything that reduces the communication cost of downloading data, and acquires accurate current location information before the intersection while reducing the communication cost.
[0026]
Incidentally, the reference numerals in parentheses of each means described above are an example showing the correspondence with specific means described in an embodiment described later.
[0027]
DETAILED DESCRIPTION OF THE INVENTION
In FIG. 1, the structure of the mobile communication network of the vehicle-mounted radio | wireless communication apparatus K which concerns on one Embodiment of this invention is shown.
[0028]
The mobile communication network includes a base station B and a server S. The base station B performs wireless communication with the in-vehicle wireless communication device K, and positioning signals necessary for calculating the position of the in-vehicle wireless communication device K. Send. This positioning signal indicates the time synchronized with the GPS satellite F.
[0029]
The server S has an arithmetic processing unit E and a map database D. The arithmetic processing unit E is composed of a computer and, as will be described later, in response to a route search request from the in-vehicle wireless communication device K, searches for a route from the departure point to the destination, and the next guidance intersection in this route Each of the distances up to and including the guidance directions for each guidance intersection and processing for transmitting the distances between the sections and the guidance directions are performed. Further, as will be described later, the arithmetic processing unit E obtains the position of the in-vehicle wireless communication device K in response to the current position calculation request from the in-vehicle wireless communication device K via the base station B, and based on this position, A process for calculating the distance to the guide intersection as current location information is performed. This current location information corresponds to the current location information described in claims 1, 8, and 9.
[0030]
Further, as shown in FIG. 1, the in-vehicle wireless communication device K includes an antenna 11, a radio unit 12, a voice processing unit 13, a voice input unit 14, a voice output unit 15, a display unit 16, an operation unit 16a, a storage unit 17, A GPS antenna 18, a GPS receiver 19, a gyro 19 a, a distance sensor 19 b, and an arithmetic processing unit 20 are included.
[0031]
The radio unit 12 receives a downlink communication signal from the base station via the antenna 11 and transmits an uplink communication signal from the antenna 11 to the base station. As a radio system of the radio unit 12, a CDMA system can be used.
[0032]
The voice processing unit 13 performs digital / analog conversion of the downlink communication signal and outputs the received signal to the voice output unit 15, and analog / digital converts the transmission signal input via the voice input unit 14 to perform the uplink communication signal. Is output to the wireless unit 12.
[0033]
The voice input unit 14 is a microphone, which receives a transmission voice and outputs a transmission signal. The voice output unit 15 includes a speaker that generates a received voice based on a received signal and a ringer that generates a ringtone. Furthermore, the operation unit 16a includes keys assigned with various functions.
[0034]
The GPS receiver 19 receives each GPS signal from each GPS satellite E via the GPS antenna 18. In addition, this GPS signal is used for the position calculation of the vehicle-mounted wireless communication device K similarly to the positioning signal from the base station. The display unit 16 is a color liquid crystal display and performs various displays such as a map. Further, the gyro 19a detects an angular velocity when the vehicle is traveling in order to detect that the vehicle is bent. The distance sensor 19b detects a travel distance based on wheel rotation.
[0035]
  Storage unit 17Is, DRAM, SRAM, flash ROM, etc., and stores computer programs, road map data, and data associated with the processing of the arithmetic processing unit 20.
[0036]
The arithmetic processing unit 20 is composed of a microcomputer, a digital signal processor, and the like. As will be described later, a destination set via the operation unit 16a, a positioning signal from the base station, and each GPS signal are transmitted to the radio unit 12. To the server S, the server S calculates the current location information and route information, and performs processing for acquiring the current location information and route information from the server S.
[0037]
Next, as an operation of the present embodiment, an example in which a vehicle occupant is guided from a departure point Sa to a destination Sj as shown in FIG. 2 will be described. 2 is a diagram illustrating a route N from the departure point Sa to the destination Sj, FIGS. 3A and 4 are flowcharts illustrating processing of the in-vehicle wireless communication device K, and FIG. FIG. 3C is a flowchart showing processing of the server S. In FIGS. 3A to 3C and FIG. 4, symbol S indicates a step.
[0038]
First, the base station B transmits a positioning signal at regular intervals by repeatedly performing positioning signal transmission (S50) and standby (S51).
[0039]
Here, the user sets a destination Sj for the operation unit 16a of the in-vehicle wireless communication device K (S1). Thereafter, the arithmetic processing unit 20 of the in-vehicle wireless communication device K receives each GPS signal from each GPS satellite F via the GPS receiving unit 19 and also receives a positioning signal from the base station B via the wireless unit 12. To do. Accordingly, the arithmetic processing unit 20 sends each GPS signal, positioning signal, destination information (which indicates the latitude and longitude of the destination Sj), and a route request for requesting a route search to the server S. The signal is transmitted via the wireless unit 12 (S3). Further, the built-in distance counter that counts the travel distance of the vehicle based on the detection of the distance sensor 19b is reset.
[0040]
Next, when the base station B receives the route request signal and each GPS signal, positioning signal, and destination information transmitted in S3 (S51), the base station B receives each GPS signal, positioning signal, and destination information. And a request signal are transmitted to the server S.
[0041]
Accordingly, the arithmetic processing unit E of the server S determines YES in S102 because there is a route search request from the in-vehicle wireless communication device K. In addition to this, the arithmetic processing unit E calculates the current location (terminal position) of the in-vehicle wireless communication device K based on each GPS signal and positioning signal. Further, the arithmetic processing unit E sets the current location as the departure location Sa, and based on the departure location information indicating the coordinates of the departure location Sa, the destination information, and the road data stored in the map database D, from the departure location Sa. A route to the destination Sj is searched. In addition, the arithmetic processing unit E obtains route information to be transmitted to the in-vehicle wireless communication device K based on the route and road data as shown in FIGS. 5 and 6 (S103).
[0042]
FIG. 5 is a table showing details of the route information, and FIG. 6 is a diagram showing details of the route information together with the route N.
[0043]
Here, in FIG. 6, departure point Sa to guidance intersection Sb, guidance intersection Sb to Sc, guidance intersection Sc to Sd, guidance intersection Sd to Se, guidance intersection Sf to Sg, guidance difference point Sg to Sh, guidance intersection Sh to Si. , 1, 2, 3,... 9 are set as the section number n for each section from the guidance intersection Si to the destination Sj.
[0044]
Then, as route information, L1 is obtained as the section distance of the section number n = 1. Similarly, L2, L3, L4,... L8, L9 are obtained as the section distances of the section numbers n = 2, 3, 4,. Further, as the route information, the direction D1 is obtained as the guidance direction at the guidance intersection Sb. Similarly, D2, D3,... D9 are obtained as the guidance directions of the guidance intersections Sc, Sd,.
[0045]
In addition to this, the arithmetic processing unit E obtains map data in the belt-like area Z along the route N as shown in FIG. This map data is used when the in-vehicle wireless communication device K itself resets the route to the destination when it deviates from the route N. When the arithmetic processing unit E obtains the map data and the route information in this way, the map data and the route information are transmitted to the base station B (S104). Accordingly, the base station B transmits map data and route information to the in-vehicle wireless communication device K.
[0046]
  Next, when the arithmetic processing unit 20 of the in-vehicle wireless communication device K receives the map data and the route information via the wireless unit 12 (S4), the map data and the route information are stored in the storage unit 17 and the section number. n = 1 is set (S5). further,Built-inWhile resetting the timer, the voice processing unit 13 performs a process for notifying the occupant by voice that the route guidance between the departure point Sa and the guidance intersection Sb (that is, the section number 1) is started (S6).
[0047]
Next, based on the detection of the distance sensor 16b, the arithmetic processing unit 20 obtains a travel distance Lm from the process of the route search request process (S3) to the current time (that is, from the departure point Sa to the current location). Based on the travel distance Lm and the section distance L1, the distance from the current location to the guidance intersection Sb (hereinafter referred to as the remaining distance Wz) is obtained (Wz = L1-Lm), and this remaining distance Wz is shown in FIG. In this manner, the display unit 16 displays the image (S7). Further, the arithmetic processing unit 20 causes the display unit 16 to display the guidance direction D1 at the guidance intersection Sb with the arrow Y. In FIG. 8, the remaining distance Wz from the current location to the guidance intersection Sb is 2 km, and the guidance direction D1 is on the right.
[0048]
Next, the arithmetic processing unit 20 determines whether or not the vehicle is bent based on the angular velocity detection of the gyro 19a (S8). If it is determined that the vehicle is not bent, that is, the vehicle is traveling straight, it is determined whether or not the remaining distance Wz is smaller than the predetermined distance la (S9). If the remaining distance Wz is larger than the predetermined distance la, NO is determined.
[0049]
Next, the arithmetic processing unit 20 determines whether or not a predetermined period ta has elapsed after the start of route guidance for the section number 1 (that is, after the processing of S6) based on the timing of the built-in timer (S92). When it is determined that the predetermined period ta or more has not elapsed since the start of the route guidance for the section number 1, based on the accumulated travel distance Ls by the distance counter, the current time after the processing of the route request process (ie, from the departure point Sa to the current location) ) Is determined as to whether or not the travel distance is larger than the set distance lb (S93). When it is determined that the travel distance Ls after the route request process is smaller than the set distance lb, the built-in timer is incremented and the remaining distance display process (S7) is performed.
[0050]
Thereafter, it is determined that the vehicle has traveled straight, it is determined that the remaining distance Wz is larger than the predetermined distance la, and it is determined that the predetermined period ta or more has not elapsed after the start of the route guidance for the section number 1 As long as it is determined that the travel distance Ls is smaller than the set distance lb, the remaining distance display process (S7), the bending determination process (S8), the remaining distance determination process (S9), the timer determination process (S92), The travel distance determination process (S93) and the timer increment process (S13) are repeated. Thereby, the remaining distance display to the guidance intersection Sb by the display unit 16 is updated based on the detection of the distance sensor 16b.
[0051]
Here, when the vehicle approaches the guidance intersection Sb and the arithmetic processing unit 20 determines that the remaining distance Wz is smaller than the predetermined distance la in S9, the position detection using the server S is performed as follows. .
[0052]
That is, in order to request the server S to calculate the current location information, the arithmetic processing unit 20 transmits a request signal, each GPS signal, and a positioning signal to the base station B via the wireless unit 12 (S10). ). Further, the calculation prohibition flag X is set to prohibit the server S from requesting the calculation of the current location information (S11).
[0053]
Thereafter, when the base station B receives the transmitted request signal, each GPS signal, and positioning signal (S51), it transmits the request signal, each GPS signal, and positioning signal to the server S. Accordingly, the arithmetic processing unit E of the server S determines that the request signal, each GPS signal, and positioning signal have been received as YES in S101, and there is a request for calculation of current location information instead of a route search request. As a result, NO is determined in S102 and YES is determined in S105.
[0054]
Next, the arithmetic processing unit E of the server S calculates the current location based on each GPS signal and positioning signal, calculates the distance from the current location to the guidance intersection Sb (S106), and uses this distance as the current location information as a base. It transmits to the vehicle-mounted wireless communication device K via the station B (S107). Accordingly, the in-vehicle wireless communication device K can receive the current location information from the server S via the base station B (S11b).
[0055]
Here, the arithmetic processing unit 20 of the in-vehicle wireless communication device K updates the display of the remaining distance Wz based on the current location information from the server S. Specifically, the arithmetic processing unit 20 displays the “distance from the current location calculated by the server S to the guidance intersection Sb” on the display unit 16 instead of the remaining distance Wz.
[0056]
Thereafter, as long as the arithmetic processing unit 20 determines that the vehicle is traveling straight and determines that the remaining distance Wz is smaller than the predetermined distance la, the calculation processing unit 20 requests the own position calculation process (S10), and the distance display update process. Except (S12), the timer reset process (S6), the remaining distance display process (S7), the bending determination process (S8), the remaining distance determination process (S9), and the flag X set process (S91) are repeated. Note that the processing of the self-position calculation processing request (S10) and the distance display update processing (S12) is not performed because the calculation prohibition flag X is set as described above.
[0057]
Here, when the vehicle bends, if the arithmetic processing unit 20 determines YES in S8 based on the detection of the gyro 19a and determines YES in S8, the direction in which the vehicle is bent is based on the detection of the gyro 19a as the guide direction D1. It is determined whether or not they match, and based on the detection of the distance line sensor 16b, whether or not the intersection where the vehicle bends matches the guidance intersection Sb is determined as follows (S14).
[0058]
First, when it is determined that the turning direction of the vehicle coincides with the guidance direction D1, the travel distance from the search request processing (S3) to the current time (ie, the departure location Sa to the current location) is obtained. When it is less than “section distance L1 + allowable error β” and more than “section distance L1−allowable error β”, the vehicle bends in the correct direction at the correct intersection according to the route, that is, the vehicle guides at the guidance intersection Sb. It is determined that the vehicle is bent in the same direction as D1.
[0059]
Next, when the section number n = 2 is set, the section number 2 (Sb to Sc) is compared with the final section number N = 9 (Si to Sj) to determine whether or not the route guidance has ended. (S18). Since the section number 2 is smaller than the last section number 9, it is determined as NO because the route guidance has not been completed. While resetting the built-in distance counter, the calculation prohibition flag X is reset (S18a), and the request for calculating the current location information to the server S is permitted.
[0060]
  Next, the arithmetic processing unit 20 performs processing for notifying the occupant by voice that the guidance between the guidance intersections Sb to Sc is started by the voice processing unit 13 (S6). Thereafter, based on the detection of the distance sensor 16b, the arithmetic processing unit 20 travels from the departure point Sa to the current location (that is, after the search request processing (S3) to the current time).TheBased on the travel distance Lm and the section distances L1 and L2, the remaining distance Wz from the current location to the guidance intersection Sc is obtained (Wz = L1 + L2−Lm), and the remaining distance Wz and the guidance direction D2 are guided. Similar to the case of the intersection Sb, it is displayed on the display unit 16 (S7).
[0061]
Thereafter, the arithmetic processing unit 20 does not bend the vehicle, the remaining distance Wz is larger than the predetermined distance la, and after the start of the route guidance for the section number 2 (that is, after the processing of S6), the predetermined period ta or more does not elapse. As long as it is determined that the travel distance Ls is smaller than the set distance lb, the remaining distance display process (S7), the bending determination process (S8), the remaining distance determination process (S9), the timer determination process (S92), the travel distance The determination process (S93) and the timer increment process (S13) are repeated.
[0062]
Here, when the vehicle travels to the front of the guidance intersection Sc and the arithmetic processing unit 20 determines in S9 that the remaining distance Wz is smaller than the predetermined distance la, the current location information request processing (S10), flag X A set process (S11) is performed. Accordingly, the arithmetic processing unit E of the server S calculates the current location of the in-vehicle wireless communication device K, calculates the distance from the current location to the guidance intersection Sb (S106), and uses this distance as current location information to the base station. It transmits to the vehicle-mounted radio | wireless communication apparatus K via B (S107).
[0063]
As a result, the arithmetic processing unit 20 of the in-vehicle wireless communication device K displays the “distance from the current location calculated by the server S to the guidance intersection Sc” on the display unit 16 instead of the remaining distance Wz.
[0064]
After that, as long as the arithmetic processing unit 20 determines that the vehicle is not bent and determines that the remaining distance Wz is smaller than the predetermined distance la, the calculation processing unit 20 requests the own position calculation process (S11), the distance display update process ( Except S12), the timer reset process (S6), the remaining distance display process (S), the bending determination process (S8), the remaining distance determination process (S9), and the flag X set process (S91) are repeated.
[0065]
Here, when the vehicle bends in the guide direction D2 at the guidance intersection Sc, the arithmetic processing unit 20 determines YES in S8 because the vehicle is bent, and the vehicle is bent based on the detection of the gyro 19a. It is determined that the direction matches the guide direction D2.
[0066]
In this case, the arithmetic processing unit 20 calculates the travel distance from the time when the vehicle bends in the guidance direction D2 at the guidance intersection Sb to the current time (that is, the travel distance from the determination of YES in the previous S14 to the current time). When calculated based on the detection of the distance sensor 16b, this travel distance is less than “section distance L2 + allowable error β” and more than “section distance L2—allowable error β”, so that the vehicle is correct at the correct intersection according to the route. It is determined that the vehicle is bent in the direction (S14).
[0067]
Next, when the section number n = 3 is set in S17, the arithmetic processing unit 20 performs S7 to S11, S11b, S12 to S14, S17 of the transition after the timer reset process (S6), as in the case of the section number 2. Each process of S18a and S91-S93 is performed.
[0068]
Thus, when the vehicle bends in the same direction as the guidance direction D2 at the guidance intersection Sc, the section distance L3 to the next guidance intersection Se and the guidance direction D3 are displayed on the display unit 16. Thereafter, when the remaining distance Wz to the next guidance intersection Se is less than the predetermined distance la, the server S is used to detect the current location information (distance from the current location to the guidance intersection Se), and based on this current location information, the next location information is detected. Update the display distance to the guidance intersection.
[0069]
Thereafter, when the vehicle bends in the same direction as the guidance directions D3, D4,... D7 at each of the guidance intersections Sd, Se... Sh, the arithmetic processing unit 20 makes a section distance Ln (4 ≦ n ≦ 8) and the guide direction Dn (4 ≦ n ≦ 8) are displayed on the display unit 16 (S7). When the vehicle approaches the next guidance intersection and the remaining distance Wz to the next guidance intersection is less than the predetermined distance la (S9: YES), the current location information is detected using the server S (S10). The display distance to the next guidance intersection is updated based on the current location information (S12).
[0070]
Further, when the vehicle bends in the same direction as D8 at the guidance intersection Si, the arithmetic processing unit 20 displays the section distance L9 of the guidance intersections Si to Sj on the display unit 16 (S7), and intersection determination processing (S14), The section number setting process (S17) and the route end determination process (S18) are executed to end the guidance process.
[0071]
  If the arithmetic processing unit 20 determines in S92 that the predetermined period ta or more has elapsed after the start of route guidance for each section, the process proceeds to S94, where the count value T of the built-in timer is decremented by the predetermined period ta. (T = T-ta). Thereafter, the arithmetic processing unit 20 performs S10, S11bSimilarly to the process of, current location information is detected using the server S (S10b, S10cThe display distance to the next guidance intersection is updated based on the current location information (S10d).
[0072]
Thereafter, as long as the vehicle advances straight, the remaining distance Wz is larger than the predetermined distance la, and the count value of the built-in timer is equal to or longer than the predetermined period ta, the arithmetic processing unit 20 performs the remaining distance display process (S7). Bending determination processing (S8), remaining distance determination processing (S9), timer determination processing (S92), timer decrement processing (S94), current location information request processing (S10b), current location information reception processing (S10d), remaining distance display The update process (10c) and the timer increment process (S13) are repeated.
[0073]
Thus, when it is determined that the vehicle is not bent and the remaining distance Wz is larger than the predetermined distance la, the current location information is detected using the server S every predetermined period ta, and the next time is detected for each detection. Update the display distance to the guidance intersection.
[0074]
  If the arithmetic processing unit 20 determines in S93 that the integrated travel distance Ls of the distance counter is larger than the set distance lb, the calculation processing unit 20 decrements the integrated travel distance Ls of the distance counter by the set distance lb (Ls = Ls-lb). In addition to this, S10, S11bSimilarly to the process of, current location information is detected using the server S (S10b, S10cThe display distance to the next guidance intersection is updated based on the current location information (S10d).
[0075]
  Thereafter, the arithmetic processing unit 20 determines that the vehicle travels straight, the remaining distance Wz is larger than the predetermined distance la, and the count value of the built-in timer is the predetermined period ta.Smaller thanFurther, as long as it is determined that the integrated travel distance Ls of the distance counter is larger than the set distance lb, the remaining distance display process (S7), the bending determination process (S8), the remaining distance determination process (S9), and the timer determination process ( S92), travel distance determination processing (S93), distance counter decrement processing (S95), current location information request processing (S10b), current location information reception processing (S10d), remaining distance display update processing (10c), timer increment processing (S13) repeat.
[0076]
Thus, when the vehicle travels straight and the remaining distance Wz is determined to be larger than the predetermined distance la, the current location information is detected using the server S every time the vehicle travels the travel distance Ls, Each time this is detected, the display distance to the next guidance intersection is updated.
[0077]
Further, after determining YES in S8 that the vehicle is bent in S8, the arithmetic processing unit 20 determines NO in S14 when the direction in which the vehicle is bent does not match the guide direction. Or after determining with YES in S8, when the intersection where the vehicle bends differs from the applicable guidance intersection, it determines with NO at S14. As described above, when NO is determined in S14, it is determined whether or not there is map data for guiding an occupant from the current location to the destination Sj although the route has been deviated (S15).
[0078]
Here, as described above, when the map data is received from the arithmetic processing unit E together with the route information, it is determined as YES because there is map data. Along with this, the arithmetic processing unit 20 searches for the route to the destination Sj based on the map data, and obtains the section distance and guidance direction to the next guidance intersection to be guided in this route. Based on the section distance and the guidance direction, the processes after S5 are executed in the same manner as described above. As a result, even if the route is off the route, if there is map data, there is no need for the server S to search for the route via communication with the base station B, and communication costs are not incurred.
[0079]
  Furthermore, there is no map data in S15, and NO is determined in S15.TheSometimes, since the process proceeds to the process of S2, the subsequent processes of the position calculation information acquisition means (S2) are described above.TanoSince the process is executed, the route can be re-searched using the server S.
[0080]
As described above, in order to reliably guide the occupant to the next intersection to be guided according to the route, it is necessary to notify the occupant of the exact distance to the intersection when the vehicle arrives before the intersection. is there. Accordingly, the in-vehicle wireless communication device K needs to acquire accurate current location information when the vehicle reaches the intersection.
[0081]
For example, the in-vehicle wireless communication device K acquires the current location information from the server S at regular intervals, so that when the host vehicle arrives in front of the guidance intersection, the vehicle location communication inevitably provides accurate current location information. Although it may be possible to obtain it from the network, an excessive communication cost is required.
[0082]
On the other hand, when the distance from the vehicle position to the guidance intersection is less than the predetermined distance, the server S can calculate the current location information and acquire the current location information via the base station B. Thus, the current location information can be acquired from the server S only when the distance from the vehicle position to the guidance intersection is less than the predetermined distance. Therefore, accurate current location information can be acquired when the vehicle reaches before the guidance intersection while reducing communication costs.
[0083]
In addition, when the vehicle travels off the route and the in-vehicle wireless communication device K does not have map data for performing route search by itself, the server S is used to guide the occupant to the destination Sj. It is necessary to make a route re-search request and a request for calculating current location information. For this reason, it is necessary to generate a trigger for making a route re-search request (including a departure location calculation request). Therefore, in this embodiment, the timing at which the vehicle deviates from the route is detected using the gyro 19c, and a route re-search request is made to the server S at a good timing by using this timing as the trigger. be able to.
[0084]
In the present embodiment, since the route guidance is performed only by displaying the distance to the next guidance intersection to be guided and the guidance direction (turning corner information) on the display unit 16, the map used for the map display is used. No data is required, and there is no need to download this map data as disclosed in JP-A-2001-84493. In addition, as described above, when receiving the current location information, distance, guidance direction, etc. as turning corner information, when the vehicle arrives in front of the intersection, an accurate distance from the vehicle position to the guidance intersection is obtained. Since the passenger can be notified, reliable route guidance can be given to the passenger.
[0085]
  In the above embodiment, when the in-vehicle wireless communication device K makes a route re-search request to the server S, all the section distances L1, L2... L9, the guidance directions D1, D2 from the departure point Sa to the destination Sj. ... D8 is acquired from the server S. However, when the route is re-searched out of the route, part of the section distance and the guidance direction acquired from the server S is not used for route guidance. , This some data wastedInThere is a possibility. Therefore, each time the vehicle turns at the guidance intersection, the server S communicates with the server S via the base station B to determine the section distance to the guidance intersection to be guided next and the guidance direction at the next guidance intersection from the server S. To getInThan,UselessData acquisition can be prevented.
[0086]
In the above-described embodiment, the example in which the gyro 19c is used to detect that the vehicle is bent is described. However, the present invention is not limited to this, and the steering operation angle or the like is detected, and the vehicle is based on the operation angle. It may be detected that is bent.
[0087]
Furthermore, in the above embodiment, the in-vehicle wireless communication device K has been described with respect to an example in which only the distance to the next guidance intersection and the guidance direction are displayed to perform route guidance. May be displayed, the current location may be displayed as a mark on the display map, and the section distance and the guidance direction may be displayed.
[0088]
  Moreover, in the said embodiment, if the vehicle-mounted radio | wireless communication apparatus K performs the calculation request | requirement of present location information with respect to the server S (S10, S10b),Server SWhen finding the current location of the in-vehicle wireless communication device KBothThe example in which the distance from the current location to the next guidance intersection to be guided is obtained and this distance is transmitted as the current location information to the in-vehicle wireless communication device K has been described. When the current location (latitude, longitude) of the wireless communication device K is obtained, the current location itself may be transmitted to the in-vehicle wireless communication device K as current location information. In this case, the in-vehicle wireless communication device K needs to obtain a distance from the current location to the next guidance intersection to be guided based on the current location information.
[0089]
  Hereinafter, the correspondence relationship between the above-described embodiment and the configuration of the scope of the claims will be described. Step S2 corresponds to a receiving unit, step S1 corresponds to a setting unit, and steps S3 and S4 correspond to a path information acquisition unit. The distance sensor 19b corresponds to the measuring means, step S9 corresponds to the travel distance determining means, and step S910, S11b corresponds to current location information acquisition means, the gyro 10a corresponds to detection means, and the display unit 16displayStep S12 corresponds to a display update unit, step S92 corresponds to a time determination unit, and steps S10b and S10c are claimed.4, 5The step 10d corresponds to the present location information acquisition means described in claim 10.4, 5A positioning signal and a GPS signal corresponding to the display update means described in (1) correspond to positioning information, a guidance direction corresponds to direction information, and a guidance intersection to be guided next corresponds to an intersection to be bent next.
[Brief description of the drawings]
FIG. 1 is a diagram showing a configuration of a mobile communication network according to an embodiment of the present invention.
FIG. 2 is a diagram showing a route searched for by the server shown in FIG. 1;
FIG. 3 is a flowchart showing a part of each process of the in-vehicle wireless communication device, the base station, and the server shown in FIG. 1;
4 is a flowchart showing the rest of the processing of the in-vehicle wireless communication device shown in FIG.
FIG. 5 is a chart showing section distances and guidance directions obtained by the server shown in FIG. 1;
6 is a diagram showing a section distance and a guidance direction shown in FIG. 5 together with a route.
7 is a diagram for explaining map data obtained by the server shown in FIG. 1; FIG.
8 is a diagram showing a display of the in-vehicle wireless communication device shown in FIG. 1. FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 11 ... Antenna, 12 ... Radio | wireless part, 13 ... Audio | voice processing part, 14 ... Audio | voice input part,
15 ... Audio output unit, 16 ... Display unit, 16a ... Operation unit, 17 ... Storage unit,
18 ... GPS antenna, 19 ... GPS receiver, 19a ... Gyro,
19b ... distance sensor, 20 ... arithmetic processing unit, S ... server, B ... base station.

Claims (5)

An in-vehicle navigation device capable of wireless communication with a base station of a mobile communication network,
Receiving means (S2) for receiving positioning information necessary for calculating the vehicle position;
Setting means (S1) for setting the destination;
And the set destination with the received positioning information performs transmission to the route search request to the base station, in the mobile communication network based on the transmitted positioning information and the destination of that vehicle While calculating the present location and searching for a route from the present location of the host vehicle to the destination, distance information to an intersection to be bent next along the searched route and direction information to be bent at the intersection are mobile communication Route information acquisition means (S3, S4) for calculating by the network and acquiring the calculated distance information and direction information via the base station;
Measuring means (19b) for measuring the travel distance of the own vehicle;
Display means (16);
Display control means (S7) for displaying the acquired distance information and direction information on the display means, and updating the distance information displayed on the display means based on the measured travel distance; ,
Based on the measured travel distance and the acquired distance information, travel distance determination means (S9) for determining whether the distance from the own vehicle position to the intersection to be bent next is less than a predetermined distance; ,
When the travel distance determination means determines that the distance from the vehicle position to the next intersection to be bent is less than a predetermined distance, the received positioning information is transmitted to the base station and transmitted. Current location information acquisition means (S11, S11b) for causing the mobile communication network to calculate the current location information of the vehicle based on the positioning information, and acquiring the calculated current location information via the base station;
An in-vehicle navigation device comprising: a display update unit (S12) that updates the distance information displayed on the display unit based on the acquired current location information . Wherein the display control unit, based on the travel distance in which the route search request is the measurement from the time it was made, in claim 1, characterized in that updating the distance information displayed on said display means The on-vehicle navigation device described. Have a detection means (19a) for detecting that the vehicle has curved at the intersection, that the vehicle is bent at the intersection every time the detecting circuit detects, said path information acquiring unit, wherein vehicle navigation system according to the distance information and direction information to the intersection and then turn to the claim 1 or 2, characterized in that to get through the base station. Time determination means (S92) for determining whether or not a certain period of time has elapsed,
Each time the timekeeping determination means determines that the predetermined period has elapsed, the received positioning information is transmitted to the base station, and the current location of the vehicle is transmitted through the mobile communication network based on the transmitted positioning information Current location information acquisition means (S10b, S10c) for calculating information and acquiring the calculated current location information via the base station;
Based on the obtained current location information, and the display updating means for updating the display on the display unit Tei Ru said distance information (10d), in any one of claims 1 to 3, characterized in that it has a The on-vehicle navigation device described. Based on the measured travel distance, travel determination means (S93) for determining whether or not the vehicle has traveled more than a certain distance;
Each time the travel determination means determines that the host vehicle has traveled more than a certain distance, the received positioning information is transmitted to the base station, and the host vehicle is transmitted through the mobile communication network based on the transmitted positioning information. Current location information acquisition means (S10b, S10c) for calculating the current location information and acquiring the calculated current location information via the base station;
Based on the obtained current location information, and the display updating means for updating the display on the display unit Tei Ru said distance information (10d), in any one of claims 1 to 3, characterized in that it has a The on-vehicle navigation device described.

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