JP2020088436A - Position determination system and position determination system control method - Google Patents

Abstract

To provide a position determination system and position determination system control method capable of achieving both of improvement of accuracy in determining a position of a portable terminal and suppression of an increase of power consumption.SOLUTION: A vehicle 1 has a position determination system 30 for determining a position of a portable terminal 2 with respect to the vehicle 1 when radio communication is to be performed with the portable terminal 2. The position determination system 30 includes: a position determination section 31 for determining a position of the portable terminal 2 with the use of an average value of reception intensities of multiple position detection signals transmitted between the portable terminal 2, and an outdoor antenna 16 and an indoor antenna 17 of the vehicle 1; and a transmission control section 33 for controlling a transmission interval of a position detection signal. The transmission control section 33 changes over the outdoor antenna 16 and the indoor antenna 17 between a burst state where a predetermined number of position detection signals are consecutively transmitted in a regulated period and a non-burst state where a position detection signal is transmitted by allowing a transmission interval to be longer than that of the burst state.SELECTED DRAWING: Figure 1

Description

The present invention relates to a position determination system that determines the position of a mobile terminal when the mobile terminal communicates with a communication partner, and a control method of the position determination system.

Conventionally, for example, in a vehicle, there is known an authentication system that controls the vehicle through wireless communication between a mobile terminal carried by a user and an in-vehicle device mounted in the vehicle. As an authentication system, a smart verification system is known in which a mobile terminal automatically responds to a radio wave transmitted from a vehicle-mounted device and performs ID verification (smart verification) by wireless communication.

Patent Document 1 discloses a smart verification system including a position determination system that determines the position of a mobile terminal with respect to a vehicle. In this position determination system, the reception intensity when the radio wave transmitted from the vehicle is received by the mobile terminal is measured, and the position where the reception intensity matches is determined as the position of the mobile terminal. In the smart verification system, the position determination system determines whether the mobile terminal is located outside or inside the vehicle.

JP, 2018-12933, A

By the way, if the position of the mobile terminal is determined by using a parameter based on a plurality of radio waves, such as an average value, the accuracy of the position determination can be expected to improve. However, on the other hand, there is a problem that power consumption is increased by transmitting a plurality of radio waves in a short time.

An object of the present invention is to provide a position determination system and a control method of the position determination system, which are capable of both improving the accuracy of the position determination of a mobile terminal and suppressing the increase in power consumption.

The position determination system for solving the above problem is a position determination system that determines the position of the mobile terminal when the mobile terminal wirelessly communicates with the communication partner, and the mobile terminal and the communication partner On the other hand, using a parameter based on a plurality of radio waves transmitted intermittently repeatedly, a position determination unit that determines the position of the mobile terminal with respect to the communication partner, and a transmission that controls the transmission interval of the transmission unit that transmits the radio waves. A control unit, wherein the transmission control unit operates the transmission unit in a burst state in which a predetermined number of the radio waves are continuously transmitted in a prescribed period, and the transmission interval is extended from the burst state. Switch between non-burst states that transmit radio waves.

A control method of a position determination system for solving the above-mentioned problem is a control method of a position determination system that determines the position of the mobile terminal when the mobile terminal and a communication partner wirelessly communicate with each other. And a step of determining the position of the mobile terminal with respect to the communication partner by using a parameter based on a plurality of radio waves intermittently repeatedly transmitted from one of the communication partners to the other, and transmission of a transmission unit that transmits the radio wave. A step of controlling an interval, wherein the step of controlling the transmission interval is configured so that the operation of the transmitter is performed in a burst state in which a predetermined number of radio waves are continuously transmitted in a prescribed period, and Switching between a non-burst state in which the radio wave is transmitted by extending the transmission interval.

INDUSTRIAL APPLICABILITY The position determination system and the control method of the position determination system according to the present invention make it possible to improve the accuracy of the position determination of the mobile terminal and suppress the increase in power consumption.

The block diagram which shows the structure of the position determination system in an authentication system. The figure which shows the antenna provided in a vehicle, and a prescribed position (area). The flowchart which shows the flow of switching of the state of an antenna by a transmission control part. The figure which shows the transmission timing of the position detection signal in a measurement mode. The flowchart which shows the flow of the process of a position determination. The figure which shows the synchronization of the switching timing to a burst state between an outdoor antenna and an indoor antenna by a transmission synchronization part.

Hereinafter, one embodiment of the position determination system will be described with reference to FIGS.
As shown in FIG. 1, the vehicle 1 as a communication partner includes an authentication system 3 that authenticates whether the mobile terminal 2 is correct or not through wireless communication. The mobile terminal 2 is preferably a high-performance mobile phone having a telephone function and capable of communicating with the vehicle 1 using short-range wireless communication. The authentication system 3 of this example is a short-range wireless verification system that executes ID verification by short-range wireless communication triggered by communication from the vehicle 1. The short-range wireless communication is preferably, for example, Bluetooth (registered trademark) communication.

The vehicle 1 is provided with a verification ECU (Electronic Control Unit) 4 that performs ID verification, a body ECU 5 that manages the power supply of in-vehicle electrical components, and an engine ECU 7 that controls the engine 6. These ECUs are connected through a communication line 8 inside the vehicle. The communication line 8 is composed of, for example, a CAN (Controller Area network) or a LIN (Local Interconnect network).

The electronic key ID and the key unique key of the mobile terminal 2 registered in the vehicle 1 are written and stored in the memory 9 of the verification ECU 4. In the authentication system 3, a series of ID collation is automatically executed by mutual communication between the collation ECU 4 and the mobile terminal 2, and the door lock is locked and unlocked and the engine is started on condition that the ID collation is established. Is allowed.

The body ECU 5 controls the operation of the door lock mechanism 11 as a mechanical portion that locks and unlocks the vehicle door 10. The vehicle door 10 is provided with an exterior door handle 12 for operating the opening and closing of the vehicle door 10. The exterior door handle 12 is provided with a touch sensor 13 that detects a user's touch operation on the exterior door handle 12 as a trigger for unlocking the door, for example. Further, the vehicle exterior door handle 12 is provided with a lock button 14 that is operated, for example, when locking the door. The body ECU 5 controls the operation of the door lock mechanism 11 based on the detection signals of the touch sensor 13 and the lock button 14 when the ID verification is established and the portable terminal 2 is located outside the vehicle 1. .

The engine ECU 7 controls the operation of the engine 6 of the vehicle 1. The vehicle 1 is provided with an engine switch 15 for operating the power transition of the engine 6. The engine switch 15 is preferably a push-type switch, for example. The engine ECU 7 controls the transition of the engine 6 by operating the engine switch 15 under a predetermined condition. The predetermined condition here means that ID verification is established, the portable terminal 2 is located inside the vehicle 1, and the brake pedal (not shown) of the vehicle 1 is stepped on. , The transmission of the vehicle 1 is in the parking range, and a combination thereof.

The vehicle 1 includes an outdoor antenna 16 and an indoor antenna 17 for performing near field communication with the mobile terminal 2. The outdoor antenna 16 is provided outside the vehicle 1. The indoor antenna 17 is provided on the indoor side of the vehicle 1. The outdoor antenna 16 and the indoor antenna 17 of this example perform Bluetooth communication with the mobile terminal 2, and in the case of this example, perform BLE (Bluetooth Low Energy) communication. The outdoor antenna 16 and the indoor antenna 17 have their own unique antenna IDs. In the BLE communication of this example, the mobile terminal 2 is a master and the vehicle 1 is a slave. The relationship between the master and the slave is not limited to this, and the vehicle 1 may be the master and the mobile terminal 2 may be the slave. The outdoor antenna 16 and the indoor antenna 17 periodically transmit an advertisement message to an area near the vehicle 1 in a predetermined order.

The mobile terminal 2 includes a terminal control unit 20 that controls the operation of the mobile terminal 2, a network communication module 21 that performs network communication in the mobile terminal 2, and a terminal communication unit that performs short-range wireless communication (BLE communication) in the mobile terminal 2. And 22. The terminal control unit 20 is provided with a user interface application (not shown) that manages the operation of the authentication system 3 in the mobile terminal 2. The terminal control unit 20 uses the user interface application to execute various processes such as ID collation with the vehicle 1, locking/unlocking operation of the vehicle door 10, and starting operation of the engine 6.

The electronic key ID and the key unique key of the mobile terminal 2 are written and stored in the memory 24 of the mobile terminal 2. The electronic key ID and the key unique key are acquired from a server or the like through network communication, for example, and are registered (electronic key registration) in the vehicle 1 through near field communication.

When the mobile terminal 2 receives the advertisement message from the vehicle 1 and establishes the BLE communication connection with the vehicle 1, the mobile terminal 2 automatically performs ID verification by mutual communication through the BLE communication with the vehicle 1. For example, when the electronic key registration of the mobile terminal 2 is completed and the BLE communication connection is established between the vehicle 1 and the mobile terminal 2, the electronic key ID is transmitted and received between the verification ECU 4 and the terminal control unit 20. The electronic key ID is verified, and cryptographic authentication such as challenge response authentication using the key unique key is performed. When the verification ECU 4 confirms that the verification and the authentication are established, the verification ECU 4 determines that the ID verification is established. It should be noted that the series of ID collation is automatically executed without the user operating the mobile terminal 2 or the vehicle 1.

The authentication system 3 includes a position determination system 30 that determines the position of the mobile terminal 2 with respect to the vehicle 1 when the vehicle 1 and the mobile terminal 2 communicate with each other. The position determination system 30 of the present example determines at which position (area) the mobile terminal 2 is relative to the vehicle 1 when the vehicle 1 and the mobile terminal 2 perform ID verification. In addition, this position determination may be performed at any timing during ID collation communication. That is, the position determination may be performed before ID verification, after ID verification, or during ID verification.

As shown in FIG. 2, in the case of this example, one outdoor antenna 16 and one indoor antenna 17 are provided in the vehicle 1. The position determination system 30 determines in which of the outdoor area Ea and the indoor area Eb the mobile terminal 2 is located based on the radio waves from these antennas. Note that these areas may be changed appropriately according to the location and the number of antennas to be arranged.

Returning to FIG. 1, the position determination system 30 includes a position determination unit 31 that determines the position of the mobile terminal 2 with respect to the vehicle 1. The position determination unit 31 of this example is provided in the verification ECU 4 of the vehicle 1. The position determination unit 31 causes the outdoor antenna 16 and the indoor antenna 17 to BLE-transmit the position detection signal Sd including the antenna ID. In the series of position determination process, the position detection signal Sd is transmitted from the outdoor antenna 16 and the indoor antenna 17 a plurality of times. Further, the transmission powers of the position detection signals Sd from the outdoor antenna 16 and the indoor antenna 17 are the same.

The position determination system 30 includes a measurement unit 32 that measures the reception intensity of radio waves between the outdoor antenna 16 and the indoor antenna 17 and the mobile terminal 2 for each radio wave of each frequency (each channel). The measurement unit 32 of this example is provided in the terminal control unit 20 of the mobile terminal 2. Upon receiving the position detection signal Sd from the outdoor antenna 16 and the indoor antenna 17 via the terminal communication unit 22, the measurement unit 32 measures the reception strength (RSSI: Received Signal Strength Indicator) of the position detection signal Sd. Here, the reception intensity of the position detection signal Sd transmitted from the outdoor antenna 16 is defined as the reception intensity Pr1, and the reception intensity of the position detection signal Sd transmitted from the indoor antenna 17 is defined as the reception intensity Pr2. The measurement unit 32 measures the received signal strength for each received position detection signal Sd, and transmits the measured received strength (reception strength data) of the position detection signal Sd to the verification ECU 4.

When receiving the reception intensity (reception intensity data) from the measurement unit 32, the position determination unit 31 determines whether the portable terminal 2 is inside or outside the vehicle 1 from the reception intensities measured for each of the outdoor antenna 16 and the indoor antenna 17. It is determined whether it is located at. In the case of the present example, the position determination unit 31 calculates the average value of the reception intensities measured for each of the outdoor antenna 16 and the indoor antenna 17, and determines whether the portable terminal 2 is inside or outside the vehicle based on the magnitude relationship of the average values. To do. The average value is an example of a parameter based on a plurality of radio waves.

The position determination system 30 includes a transmission control unit 33 that controls the transmission intervals of the position detection signals Sd of the outdoor antenna 16 and the indoor antenna 17. The transmission control unit 33 transmits the position detection signal Sd to the outdoor antenna 16 and the indoor antenna 17 in a burst state in which a predetermined number of position detection signals Sd are continuously transmitted in a prescribed period, and a transmission interval is extended from the burst state. Switch to the non-burst state to send.

The transmission control unit 33 switches between the standby mode in which the outdoor antenna 16 and the indoor antenna 17 remain in the non-burst state and the measurement mode in which the burst state and the non-burst state are periodically switched. The transmission control unit 33 sets the outdoor antenna 16 and the indoor antenna 17 to the standby mode when the mobile terminal 2 is not located near the vehicle 1, and sets the measurement mode when the mobile terminal 2 is located near the vehicle 1. Note that the case where the mobile terminal 2 is located in the vicinity of the vehicle 1 includes the cases where the reception intensities Pr1 and Pr2 are larger than the threshold value, the case where the operation unit 35 that operates the vehicle 1 is operated, and a combination thereof. The operation unit 35 includes, for example, the touch sensor 13, the lock button 14, the engine switch 15, and buttons (not shown) for operating door lock/unlock and engine start in the user interface application.

The position determination system 30 includes a transmission synchronization unit 34 that adjusts the timing of switching to the burst state between the outdoor antenna 16 and the indoor antenna 17. The transmission synchronization unit 34 simultaneously switches the outdoor antenna 16 and the indoor antenna 17 to the burst state when the operation unit 35 that is operated to operate the vehicle 1 is operated.

Next, the operation and effect of the position determination system (transmission control unit 33) will be described with reference to FIGS. Here, a case where the mobile terminal 2 approaches the vehicle 1 from a distance from the vehicle 1 will be described. In this example, as a premise, the position determination unit 31 performs radio wave transmission from the outdoor antenna 16 and the indoor antenna 17 on a regular or irregular basis when monitoring establishment of wireless communication between the vehicle 1 and the mobile terminal 2. .. In the case of this example, it is assumed that the position detection signal Sd is transmitted from the outdoor antenna 16 and the indoor antenna 17.

As shown in FIG. 3, in step S101, when the mobile terminal 2 is not located near the vehicle 1, the transmission control unit 33 sets the outdoor antenna 16 and the indoor antenna 17 in the standby mode. In the standby mode, the outdoor antenna 16 and the indoor antenna 17 execute radio wave transmission in a non-burst state. That is, when the mobile terminal 2 is not located near the vehicle 1, the position determination system 30 monitors the rough position of the mobile terminal 2 using the non-burst state.

As shown in FIG. 4, the non-burst state of the present example refers to a transmission state of “t2” in which the transmission interval of the radio waves transmitted intermittently is wide. The burst state in this example is a transmission state of "t1" in which the transmission interval of the repeatedly transmitted radio waves is intermittently narrow.

Returning to FIG. 3, in step S102, the transmission control unit 33 determines whether the mobile terminal 2 is located near the vehicle 1 based on the position detection signal Sd transmitted in the non-burst state. In the case of this example, the transmission control unit 33 acquires the reception intensity data of the reception intensities Pr1 and Pr2 measured by the measurement unit 32 via wireless. Then, the transmission control unit 33 determines whether or not the reception intensity data is equal to or more than the threshold value, and when the reception intensity data is equal to or more than the threshold value, determines that the mobile terminal 2 is located near the vehicle 1. When the mobile terminal 2 is located near the vehicle 1, the transmission control unit 33 proceeds to step S103. On the other hand, when the reception intensities Pr1 and Pr2 are less than the threshold value, the transmission control unit 33 determines that the mobile terminal 2 is not located near the vehicle 1. When the transmission control unit 33 determines that the mobile terminal 2 is not located near the vehicle 1, the transmission control unit 33 leaves the outdoor antenna 16 and the indoor antenna 17 in the standby mode.

In step S103, when it is determined that the mobile terminal 2 is located near the vehicle 1, the transmission control unit 33 sets the outdoor antenna 16 and the indoor antenna 17 in the measurement mode. In the measurement mode, the outdoor antenna 16 and the indoor antenna 17 transmit the position detection signal Sd at transmission intervals according to the respective states while periodically and repeatedly switching between the burst state and the non-burst state.

As shown in FIG. 5, in step S201, the position determination unit 31 determines the position of the mobile terminal 2 by transmitting the position detection signal Sd from the outdoor antenna 16 and the indoor antenna 17 at each timing of the non-burst state and the burst state. Send it. In the measurement mode, the outdoor antenna 16 and the indoor antenna 17 repeatedly switch between the burst state and the non-burst state at the cycle T, and transmit the position detection signal Sd at a transmission interval according to each state (see FIG. 4 ).

In step S202, the measurement unit 32 measures the reception intensity of the position detection signal Sd. The position detection signal Sd may include each antenna ID, and the mobile terminal 2 on the receiving side may be able to identify which of the outdoor antenna 16 and the indoor antenna 17 is the radio wave. Upon receiving the position detection signal Sd, the measuring unit 32 measures the reception intensity (reception intensity Pr1 and reception intensity Pr2) of the position detection signal Sd, and returns the measured reception intensity data to the outdoor antenna 16 and the indoor antenna 17. To notify you.

In the case of the present example, the position determination unit 31 repeats a series of processes of position detection signal transmission, reception intensity measurement, and reception intensity data notification by changing the frequency (channel) in each of the outdoor antenna 16 and the indoor antenna 17. Run (shown only once in Figure 5). As a result, the position determination unit 31 acquires a data group of the reception intensity Pr1 and the reception intensity Pr2 measured during communication with the mobile terminal 2 in each of the outdoor antenna 16 and the indoor antenna 17. The reception intensity data is stored in the memory 9.

In step S203, when the position determination unit 31 receives the reception intensity (reception intensity data) from the measurement unit 32, the average value of these reception intensities is calculated from the reception intensities measured for each of the outdoor antenna 16 and the indoor antenna 17. calculate. The position determination unit 31 calculates an average value from a plurality of recently received reception intensity data. For example, when the position determination unit 31 receives new reception strength data, the position determination unit 31 excludes the old reception strength data and calculates an average value from the group of reception strength data to which the new reception strength data is added. Thus, the average value is a moving average. The position determination unit 31 calculates an average value Pr1′ of the reception intensities Pr1 from the stored plurality of reception intensities Pr1. Further, the position determination unit 31 calculates an average value Pr2′ of the reception intensities Pr2 from the stored plurality of reception intensities Pr2.

The position determination unit 31 determines whether the mobile terminal 2 is located inside or outside the vehicle 1 by comparing the magnitudes of the average value Pr1′ and the average value Pr2′. When the average value Pr1′ is equal to or larger than the average value Pr2′ (Pr1′≧Pr2′), the position determination unit 31 determines that the mobile terminal 2 is located in the outdoor area Ea of the vehicle 1 (outdoor determination). On the other hand, when the average value Pr1′ is less than the average value Pr2′ (Pr1′<Pr2′), the position determination unit 31 determines that the mobile terminal 2 is located in the indoor area Eb of the vehicle 1 (indoor determination). For example, the body ECU 5 controls the operation of the door lock mechanism 11 based on the detection signals of the touch sensor 13 and the lock button 14 when the ID verification is established and the outdoor determination is made. Further, the engine ECU 7 controls the transition of the engine 6 by operating the engine switch 15 on condition that the ID collation is established and the indoor determination is made. As described above, the position determination system 30 determines in which area of the vehicle 1 the mobile terminal 2 is located, whereby control according to the position of the mobile terminal 2 becomes possible.

Note that the BLE communication connection and ID verification between the vehicle 1 and the mobile terminal 2 may be executed at any timing before, after, or during the position determination communication.
Here, the idea when the position determination of the mobile terminal 2 is performed using the average values Pr1' and Pr2' will be described. The reception intensities Pr1 and Pr2 have variations among a plurality of measurements. For example, in BLE communication, a frequency hopping method is used to switch between a plurality of channels (frequencies), and variations occur in reception strength between channels. Therefore, by comparing the magnitudes of the average values Pr1′ and Pr2′, compared with the case of comparing the reception intensities (instantaneous values) at one point of the reception intensities Pr1 and Pr2, the positions due to the variations in the reception intensities Pr1 and Pr2 are compared. The influence on the judgment is suppressed.

By the way, the transmission interval of the position detection signal Sd affects the accuracy of position determination. For example, when the transmission interval is wide and the position of the mobile terminal 2 changes, the actual position of the mobile terminal 2 and the position determined by the average values Pr1′ and Pr2′ may differ. Therefore, the accuracy of position determination is improved by narrowing the transmission interval of the position detection signal Sd. On the other hand, by extending the transmission interval of the position detection signal Sd, the power consumption for transmitting and receiving the position detection signal Sd is reduced.

As shown in FIG. 4, the outdoor antenna 16 and the indoor antenna 17 repeat the burst state and the non-burst state at the cycle T in the measurement mode. In FIG. 4, the arrow indicates the time axis, and the transmission timing of the position detection signal Sd is indicated by the solid line on the time axis. In the burst state, the outdoor antenna 16 and the indoor antenna 17 transmit the position detection signal Sd at the transmission interval t1 defined in the burst state. In the non-burst state, the outdoor antenna 16 and the indoor antenna 17 transmit the position detection signal Sd at the transmission interval t2 defined in the non-burst state. For example, the transmission interval t1 is 5 to 20 ms, the transmission interval t2 is 100 to 200 ms, and the cycle T is 500 to 1000 ms. Note that these transmission intervals and cycles are examples, and can be changed as appropriate according to the specifications.

In the burst state, the outdoor antenna 16 and the indoor antenna 17 continuously transmit a predetermined number of position detection signals Sd during a prescribed period. The predetermined number of position detection signals Sd transmitted in the burst state is preferably the same as the number of reception intensity data used by the position determination unit 31 to calculate the average values Pr1′ and Pr2′. As a result, the average values Pr1' and Pr2' can be calculated from the reception intensity data acquired during the burst state period. Therefore, by using the burst state, in the reception intensity data used for calculating the average values Pr1′ and Pr2′, the period from the acquisition of the oldest reception intensity data to the acquisition of the newest reception intensity data is shortened. .. This is advantageous for improving the accuracy of position determination.

In the non-burst state, the outdoor antenna 16 and the indoor antenna 17 transmit the position detection signal Sd with a transmission interval longer than that in the burst state. As a result, in the non-burst state, the power consumption required for transmitting the position detection signal Sd can be suppressed more than in the burst state. Further, the position determination system 30 acquires the reception intensities Pr1 and Pr2 even when the outdoor antenna 16 and the indoor antenna 17 are in the non-burst state.

When the mobile terminal 2 is not located in the vicinity of the vehicle 1, the transmission control unit 33 of this example keeps the outdoor antenna 16 and the indoor antenna 17 in the standby mode, that is, the non-burst state. it can. Further, when the mobile terminal 2 is located in the vicinity of the vehicle 1, the transmission control unit 33 causes the position determination unit 31 to perform the position determination using the reception intensity data acquired in a short period in the measurement mode including the burst state. be able to. This can improve the accuracy of position determination. Further, in the measurement mode, the burst state and the non-burst state are periodically repeated, so that the power consumption can be prevented from excessively increasing.

In the measurement mode, the number of position detection signals Sd transmitted from each antenna in the non-burst state during the period T is preferably equal to or less than the number of position detection signals Sd transmitted from each antenna in the burst state. As a result, the reception intensity data group used to calculate the average values Pr1′ and Pr2′ is likely to include the reception intensity data acquired in the burst state even in the non-burst state. That is, for the calculation of the average values Pr1′ and Pr2′, the reception intensity data group acquired mainly in the burst state can be used. The data acquired in the non-burst state corrects the average values Pr1′ and Pr2′ and is used for the control of the transmission control unit 33.

Next, the operation and effect of the transmission synchronization unit 34 will be described with reference to FIG.
As illustrated in FIG. 6, when the operation unit 35 detects an operation, the transmission synchronization unit 34 adjusts the timing at which the outdoor antenna 16 and the indoor antenna 17 are switched to the burst state. When the operation unit 35 is operated, the transmission synchronization unit 34 causes the position detection signal Sd to be transmitted in the burst state at the same timing regardless of the burst state and the non-burst state of each antenna. Since both the outdoor antenna 16 and the indoor antenna 17 are in the burst state at the same time, the average values Pr1′ and Pr2′ can be calculated accurately at the same timing.

As described above, in this example, the position determination unit 31 that determines the position of the mobile terminal 2 based on the plurality of position detection signals Sd and the transmission control unit 33 that controls the transmission interval of the position detection signal Sd are provided. Further, the transmission control unit 33 is configured to switch the outdoor antenna 16 and the indoor antenna 17 between the burst state and the non-burst state. According to this configuration, the transmission interval in the burst state is narrowed to improve the position determination accuracy. Further, in the non-burst state, it is possible to extend the transmission interval and suppress an increase in power consumption. By switching between these two states, it is possible to both improve the accuracy of the position determination of the mobile terminal 2 and suppress the increase in power consumption.

In this example, the transmission control unit 33 monitors the rough position of the mobile terminal 2 and determines whether to switch the outdoor antenna 16 and the indoor antenna 17 to the measurement mode including the burst state based on the monitoring result. did. According to this configuration, it is possible to control which of the improvement of the accuracy of the position determination and the suppression of the power consumption is prioritized according to the position of the mobile terminal 2. This contributes to both improvement in the accuracy of the position determination of the mobile terminal 2 and suppression of an increase in power consumption.

In this example, the transmission control unit 33 sets the outdoor antenna 16 and the indoor antenna 17 in the standby mode in which the reception intensity Pr1 and Pr2 of the position detection signal Sd are smaller than the threshold, and the reception intensity Pr1 and Pr2 are maintained. When is above the threshold, the measurement mode is set. According to this configuration, when the reception intensities Pr1 and Pr2 are smaller than the threshold value, it can be estimated that the mobile terminal 2 is not located near the vehicle 1. When the reception intensities Pr1 and Pr2 are equal to or greater than the threshold value, it can be estimated that the mobile terminal 2 is located near the vehicle 1. That is, depending on whether or not the mobile terminal 2 is located in the vicinity of the vehicle 1, whether to prioritize the accuracy of position determination or power consumption suppression is controlled. This can preferably control the transmission interval of the position detection signal Sd.

In this example, when the outdoor antenna 16 and the indoor antenna 17 are in the measurement mode, the number of position detection signals Sd transmitted in the non-burst state during the period T is the number of position detection signals Sd transmitted in the burst state. Below. According to this configuration, the average values Pr1′ and Pr2′ can be calculated mainly using the reception intensity data acquired in the burst state. This can maintain the accuracy of position detection when it is periodically switched between the burst state and the non-burst state.

In this example, the transmission synchronization unit 34 is provided between the outdoor antenna 16 and the indoor antenna 17 to adjust the switching timing to the burst state. According to this configuration, both the outdoor antenna 16 and the indoor antenna 17 can calculate the average values Pr1' and Pr2' based on the position detection signal Sd transmitted at the same timing in the burst state. This contributes to the improvement of the position determination accuracy.

The present embodiment can be modified and implemented as follows. The present embodiment and the following modified examples can be implemented in combination with each other within a technically consistent range.
The outdoor antenna 16 and the indoor antenna 17 may be switched to the measurement mode when the operation unit 35 is operated, and may be set to the standby mode when the operation unit 35 is not operated. That is, the transmission control unit 33 may determine whether or not the mode including the burst state of the outdoor antenna 16 and the indoor antenna 17 is set based on whether or not the operation unit 35 is operated. Also with this configuration, the transmission interval of the position detection signal Sd can be suitably controlled.

The synchronization of the switching timing of each antenna to the burst state by the transmission synchronization unit 34 is triggered by the operation of the operation unit 35, but is not limited to this. For example, synchronization may be performed at a timing when the reception intensities Pr1 and Pr2 are equal to or higher than a threshold value or at a predetermined time by a timer.

The transmission synchronization unit 34 may be omitted from the constituent elements.
When the outdoor antenna 16 and the indoor antenna 17 are periodically switched between the burst state and the non-burst state, the number of position detection signals Sd transmitted in each state during one cycle is the present embodiment. It is not limited to this, and may be changed as appropriate. That is, the number of position detection signals Sd transmitted in the non-burst state may be larger than the number of position detection signals Sd transmitted in the burst state during one cycle.

The operation unit 35 may be a touch sensor 13, a lock button 14, an engine switch 15, and a button (not shown) for operating door lock/unlock or engine start in a user interface application.

The outdoor antenna 16 and the indoor antenna 17 do not have to take the measurement mode and the standby mode, and may be switched between the burst state and the non-burst state.
The case where the mobile terminal 2 is located in the vicinity of the vehicle 1 includes the cases where the reception intensities Pr1 and Pr2 are larger than the threshold value, the case where the operation unit 35 which operates the vehicle 1 is operated, and a combination thereof. When the reception intensities Pr1 and Pr2 are used as a reference for determining that the mobile terminal 2 is located in the vicinity of the vehicle 1, when the reception intensity Pr1 and/or the reception intensity Pr2 is at least one of the threshold values or more, the mobile terminal 2 May be determined to be located near the vehicle 1.

The transmission control unit 33 is not limited to periodically switching the outdoor antenna 16 and the indoor antenna 17 between the burst state and the non-burst state, and may have no periodicity. For example, the burst state may be set only when the operation unit 35 is operated.

-The radio wave transmission interval may be switched in the non-burst state. Further, in the burst state, the radio wave transmission interval may be switched. Thus, the radio wave transmission interval may be further variable in each of the non-burst state and the burst state.

The process of monitoring the position of the mobile terminal 2 roughly using the non-burst state and switching each antenna between the non-burst state and the burst state may be omitted. For example, each antenna may be switched between the burst state and the non-burst state at a predetermined cycle regardless of the position of the mobile terminal 2.

The measuring unit 32 may be provided on the vehicle 1 side. For example, even if the position detection signal Sd transmitted from the mobile terminal 2 is received by a plurality of antennas on the vehicle 1 side and the position of the mobile terminal 2 is determined based on the magnitude relationship of the average values calculated from the reception intensities thereof. Good.

The position determination unit 31 may be provided on the mobile terminal 2 side.
The average value is not limited to the moving average, and may be other arithmetic average, geometric average, or harmonic average. Alternatively, a weighted moving average or the like may be used.

The parameter based on a plurality of radio waves is not limited to the average value, but may be the median value or the mode value. These can be appropriately changed according to the distribution (variation) of the reception strength. However, it is preferable to use the average value in terms of reliability with a small number of data and considering all data.

The position determination unit 31 is not limited to determining whether the mobile terminal 2 is located inside or outside the vehicle 1, and whether the mobile terminal 2 is on the driver seat side or the passenger seat side of the vehicle 1. , The front side or the rear side, or the coordinates of the mobile terminal 2 with respect to the vehicle 1 may be determined.

-The arrangement of the transmission unit is not particularly limited, and can be appropriately changed according to the specifications. For example, it may be arranged on the driver's seat side and the passenger's seat side of the vehicle 1 regardless of whether the vehicle 1 is indoors or outdoors.
The number of transmitting units may be one, two, three or more. That is, the number of transmitters is not limited, and a plurality of transmitters may be provided inside and outside the vehicle 1. For example, when four transmitters are provided outside the vehicle 1, the transmitters outside the vehicle include a driver seat side in front of the vehicle, a driver seat side in the rear of the vehicle, a passenger seat side in front of the vehicle, and a passenger seat in the rear of the vehicle. It may be provided on the side. Further, when the two transmitters are provided inside the vehicle 1, it may be provided on the driver seat side and the passenger seat side inside the vehicle.

The measuring unit 32 may be configured to calculate an average value of a plurality of position detection signals Sd and send back (notify) the vehicle 1 side. That is, the parameter calculation based on a plurality of radio waves may be performed on either the vehicle 1 side or the mobile terminal 2 side.

Each frequency of the plurality of position detection signals Sd (radio waves) transmitted is not limited to a channel determined by frequency hopping of BLE communication.
The size relationship serving as a reference for position determination is not limited to this embodiment, and can be changed as appropriate based on, for example, data that was tested in a state in which the position determination system 30 was mounted on the vehicle 1.

The BLE communication connection between the vehicle 1 (collation ECU 4) and the mobile terminal 2 may be performed at any time during a series of communication processes. Further, after the vehicle 1 and the mobile terminal 2 are connected for communication, the ID verification of the vehicle 1 and the mobile terminal 2 may be performed at any timing. That is, the timing at which the ID verification is performed may be before the position determination, after the position determination, or during the position determination.

-The communication standard and band of the authentication system 3 and the position determination system 30 are not limited to the embodiment, and Wi-Fi may be used, for example. Also, different bands may be used between these systems.

The method of performing the communication connection (pairing) of the near field communication between the vehicle 1 and the mobile terminal 2 is not particularly limited. For example, pairing may be performed only by operating one of the devices. Further, when the operation is performed on the vehicle 1 side at the time of pairing, a device such as a car navigation system mounted on the vehicle 1 can be applied as the input/output device. That is, when performing pairing, the operating device, operating method, authentication method, and the like can be changed as appropriate.

The mobile terminal 2 acquires the electronic key ID and the key unique key from the server through network communication, but the method is not limited to this. For example, a mode may be employed in which the electronic key ID and the key unique key registered in advance in the vehicle 1 are given to the mobile terminal 2 by logging in to the vehicle 1 (user ID and password authentication) using BLE communication.

The ID collation performed by the authentication system 3 is not limited to the electronic key ID collation and the cryptographic authentication of the key unique key, but may be any one that can confirm the correctness of the mobile terminal 2.
-In a series of authentication, the order of ID collation and position detection of the mobile terminal 2 is not particularly limited. For example, the ID collation may be performed after the position detection, or the ID collation and the position detection may be performed so as to overlap with each other.

The mobile terminal 2 is not limited to a high-performance mobile phone, and may be an electronic key tied to the vehicle 1.
The authentication system 3 and the position determination system 30 are not limited to being mounted on the vehicle 1 and can be changed to various devices and devices.

DESCRIPTION OF SYMBOLS 1... Vehicle, 2... Portable terminal, 3... Authentication system, 4... Collation ECU, 13... Touch sensor, 14... Lock button, 15... Engine switch, 16... Outdoor antenna, 17... Indoor antenna, 20... Terminal control part, 30... Position determination system, 31... Position determination unit, 32... Measuring unit, 33... Transmission control unit, 34... Transmission synchronization unit, 35... Operation unit.

Claims (7)

A position determination system for determining the position of a mobile terminal when the mobile terminal wirelessly communicates with a communication partner,
A position determination unit that determines the position of the mobile terminal with respect to the communication partner by using a parameter based on a plurality of radio waves intermittently repeatedly transmitted from one of the mobile terminal and the communication partner to the other,
A transmission control unit that controls a transmission interval of the transmission unit that transmits the radio wave;
The transmission control unit operates the transmission unit in a burst state in which a predetermined number of the radio waves are continuously transmitted in a prescribed period, and in a non-burst state in which the radio waves are transmitted with a transmission interval longer than the burst state. Position determination system to switch between and. The transmission control unit monitors a rough position of the mobile terminal with respect to the communication partner, and determines whether or not to transmit the radio wave from the transmission unit in a mode including at least the burst state based on the result of the monitoring. The position determination system according to claim 1, wherein the determination is performed. The transmission control unit causes the transmission unit to transmit the radio wave in the non-burst state when the reception intensity when the radio wave transmitted from the transmission unit is received by the other side is smaller than a threshold, and the reception intensity The position determination system according to claim 2, wherein, when is greater than or equal to the threshold value, the radio wave is transmitted from the transmission unit in a manner including at least the burst state. When the transmission control unit does not detect an operation on the operation unit provided to operate the communication partner, the transmission control unit causes the transmission unit to transmit the radio wave in the non-burst state, and operates the operation unit. The position determination system according to claim 2, wherein the radio wave is transmitted from the transmission unit in a manner including at least the burst state when the signal is detected. When the transmission unit is periodically switched between the burst state and the non-burst state by the transmission control unit, during one cycle, the radio wave transmitted by the transmission unit in the non-burst state The position determination system according to any one of claims 2 to 4, wherein the number is equal to or less than the predetermined number of the radio waves transmitted by the transmitting unit in the burst state. A plurality of the transmission units provided to the communication partner,
The position determination system according to any one of claims 1 to 5, further comprising: a transmission synchronization unit that adjusts a switching timing to the burst state among a plurality of the transmission units. A method of controlling a position determination system for determining the position of a mobile terminal when the mobile terminal and a communication partner wirelessly communicate with each other,
Using a parameter based on a plurality of radio waves intermittently repeatedly transmitted from one of the mobile terminal and the communication partner to the other, determining the position of the mobile terminal with respect to the communication partner,
A step of controlling a transmission interval of the transmission unit that transmits the radio wave,
In the step of controlling the transmission interval, the operation of the transmitter is performed in a burst state in which a predetermined number of the radio waves are continuously transmitted in a prescribed period, and the radio waves are transmitted with a transmission interval longer than that in the burst state. A control method for a position determination system that switches between a non-burst state.