MOBILE DEVICE POSITION ESTIMATE SYSTEM

Abstract

Mobile device position estimation system for estimating a relative position of a mobile device with respect to a vehicle by performing radio communication according to a predetermined communication procedure between a vehicle-mounted system (1) mounted on a vehicle and the mobile device (2) carried by a user of the vehicle, wherein the vehicle-mounted system comprises: a transceiver (12X) that is a communication module configured to send and receive radio signals to and from the mobile device; several interceptors (12A, 12B, 12C) configured to receive radio signals transmitted by the mobile device and by the transceiver; and a position estimation unit (F3).which estimates the position of the mobile device based on the result of communication between the transceiver and the mobile device and the reception states of the radio signals by the multiple respective interceptors, wherein the transceiver is configured to send a predetermined response request signal as the radio signal to the mobile device, wherein the mobile device is configured to send a response signal as a response when the mobile device receives the response request signal from the transceiver, the position estimation unit includes: a first propagation time determination unit (S105) which determines a first propagation time, which is a propagation time of the radio signal from the transceiver to the mobile device, based on a round-trip time, which is a duration from when the transceiver sends the response request signal until when the transceiver receives the response signal from the mobile device,is; a second propagation time determination unit (S107) that determines for each of the multiple interceptors a second propagation time, which is a propagation time of the radio signal from the mobile device to the interceptor, based on a signal reception interval that is a duration from when the interceptor receives the response request signal until when the interceptor receives the response signal, and the orbital period; and a position estimation processing unit (S108) that estimates the position of the mobile device based on the first propagation time determined by the first propagation time determination unit and the second propagation times determined by the second propagation time determination unit; multiple of the transceivers are included in the vehicle-mounted system; the vehicle-mounted system further includes a role determination unit (F2);the: designates one of the multiple transceivers as a host device responsible for sending the response request signal to the mobile device; and causes the transceivers, with the exception of the host device, to function as the interceptors, and in a predetermined cycle the role-setting unit changes the transceiver acting as the host device.

Description

CROSS-REFERENCE TO RELATED REGISTRATIONS

[0001] The present application is based on the Japanese patent application number 2018-151310, filed on August 10, 2018, the disclosure of which is hereby incorporated by reference. TECHNICAL AREA

[0002] The present disclosure relates to a mobile device position estimation system that estimates the position of a mobile device with respect to a vehicle based on the propagation time of a signal from the mobile device to a communication device mounted on the vehicle. STATE OF THE ART

[0003] Traditionally, various configurations have been proposed to estimate the position of a mobile device relative to a vehicle (i.e., a mobile device position estimation system) by means of radio communication between a vehicle-mounted system attached to the vehicle and the mobile device carried by the user.

[0004] Patent document 1 discloses a configuration in which a vehicle-mounted system and a mobile device are configured to enable ultra-wideband (UWB) communication, and in which the distance of the mobile device to the vehicle is estimated based on the time it takes for the vehicle-mounted system to transmit a pulse signal used in UWB communication until the vehicle-mounted system receives a response signal from the mobile device (hereinafter referred to as a "roundabout time"). For simplicity, a configuration provided in the vehicle-mounted system to perform radio communication with the mobile device is referred to as a vehicle-mounted communication device. LITERATURE ON THE STATE OF TECHNOLOGY PATENT LITERATURE

[0005] Patent document 1: JP 6093647B OVERVIEW OF THE INVENTION

[0006] To estimate the relative position of a mobile device with respect to a vehicle using the propagation time of a signal between a mobile device and a vehicle-mounted communication device disclosed in patent document 1, it is necessary, assuming the vehicle-mounted system includes several vehicle-mounted communication devices (at least three or more), to estimate the distances from each vehicle-mounted communication device to the mobile device. To estimate the distance from each vehicle-mounted communication device to the mobile device, each vehicle-mounted communication device must individually establish radio communication with the mobile device.

[0007] The present disclosure is based on these circumstances and one objective of the disclosure is to provide a mobile device position estimation system that estimates the position of a mobile device based on the propagation time of a radio signal from the mobile device to a vehicle-mounted system, and that limits the number of times radio communications are performed between the mobile device and the vehicle-mounted system for position estimation.

[0008] A first example of a mobile device position estimation system is a mobile device position estimation system for estimating a relative position of a mobile device with respect to a vehicle by performing radio communication according to a predetermined communication procedure between a vehicle-mounted system mounted on a vehicle and the mobile device carried by a user of the vehicle, wherein the vehicle-mounted system includes a transceiver, which is a communication module configured to send and receive radio signals to and from the mobile device; several interceptors configured to receive radio signals transmitted by the mobile device and by the transceiver; and a position estimation unit.which estimates the position of the mobile device based on the result of communication between the transceiver and the mobile device and the reception states of the radio signals by the multiple respective interceptors, wherein the transceiver is configured to send a predetermined response request signal as the radio signal to the mobile device, wherein the mobile device is configured to send a response signal as a response when the mobile device receives the response request signal from the transceiver, wherein the position estimation unit includes: a first propagation time determination unit, which determines a first propagation time, which is a propagation time of the radio signal from the transceiver to the mobile device, based on a round-trip time, which is a duration from when the transceiver sends the response request signal until when the transceiver receives the response signal from the mobile device.is; a second propagation time determination unit that determines, for each of the multiple interceptors, a second propagation time, which is a propagation time of the radio signal from the mobile device to the interceptor, based on a signal reception interval that is a duration from when the interceptor receives the response request signal until when the interceptor receives the response signal, and the orbital period; and a position estimation processing unit that estimates the position of the mobile device based on the first propagation time determined by the first propagation time determination unit and the second propagation times determined by the second propagation time determination unit.

[0009] According to the configuration described above, a single transmission and reception of radio signals by the transceiver and the mobile device allows the position estimation unit to determine not only the first propagation time, which is the propagation time of the signal from the transceiver to the mobile device, but also the second propagation time, which is the propagation time of the signal from the mobile device to each interceptor. The first propagation time serves as an indicator of the distance from the transceiver to the mobile device, and the second propagation time for each interceptor serves as an indicator of the distance from that interceptor to the mobile device. Therefore, the position of the mobile device can be estimated based on the first propagation time and the second propagation time for each interceptor.Furthermore, according to the above configuration, different pieces of information for estimating the position of the mobile device (in particular the first and second propagation times) are collected in a single radio communication. That is, according to the above configuration, the number of times the radio communications between the mobile device and the vehicle-mounted system are executed for position estimation can be limited in the mobile device position estimation system, which estimates the position of the mobile device based on the propagation time of the radio signal from the mobile device to the vehicle-mounted system.

[0010] A second example of a mobile device position estimation system is a mobile device position estimation system for estimating a relative position of a mobile device with respect to a vehicle by performing radio communication according to a predetermined communication procedure between a vehicle-mounted system mounted on a vehicle and the mobile device worn by a user of the vehicle, wherein the mobile device is configured to: send a response request signal, which is a radio signal that requests the vehicle-mounted system to send a response signal as a reply, and to: when the mobile device receives the response signal, send to the vehicle-mounted system a time difference message signal, which is a radio signal that specifies a round-trip time, which is the duration from receiving the response request signal to receiving the response signal.wherein the vehicle-mounted system comprises: a transceiver, which is a communication module configured to send and receive radio signals to and from the mobile device using a predetermined communication procedure; several interceptors configured to receive radio signals transmitted by the mobile device and the transceiver; and a position estimation unit, which estimates the position of the mobile device based on the result of communication between the transceiver and the mobile device and the reception states of the radio signals by the respective interceptors, wherein the transceiver is configured to send the response signal as a response when it receives the response request signal from the mobile device, and wherein the position estimation unit includes: a first propagation time determination unit, which determines a first propagation time,a propagation time determination unit, which is a propagation time of the radio signal from the transceiver to the mobile device, based on the round-trip time specified in the time difference message signal; a second propagation time determination unit, which determines for each of the multiple interceptors a second propagation time, which is a propagation time of the radio signal from the mobile device to a respective interceptor, based on a signal reception interval that is a duration from when the respective interceptor receives the response request signal until when the respective interceptor receives the response signal, and the round-trip time; and a position estimation processing unit, which estimates the position of the mobile device based on the first propagation time determined by the first propagation time determination unit and the second propagation times determined by the second propagation time determination unit.

[0011] According to the configuration of the second example described above, a single transmission and reception of radio signals by the transceiver and the mobile device of the position estimation unit allows the first propagation time and the second propagation time for each interceptor to be determined, as is the case with the configuration of the first example. Therefore, the second configuration has the same effect as the first configuration. List of characters

[0012] The foregoing and other tasks, features and advantages of the present disclosure will become clearer from the following detailed description in conjunction with the drawings. Fig. Figure 1 is a block diagram illustrating an overall configuration of a mobile device position estimation system. Fig. Figure 2 is a block diagram illustrating a configuration of a vehicle-mounted communication device. Fig. Figure 3 is a functional block diagram of a position estimation device. Fig. Figure 4 is a conceptual diagram illustrating a communication path between the vehicle-mounted system and the mobile device. Fig. Figure 5 is a flowchart illustrating the operation of the position estimating device. Fig. Figure 6 is a conceptual diagram to explain the operations of a mobile device, a host device, and an interceptor device. Fig. Figure 7 is a diagram to illustrate a relationship between a revolution time Tp and a pulse reception interval Tq. Fig. Figure 8 is a diagram illustrating a method for estimating the position of the mobile device. Fig. Figure 9 is a conceptual diagram to explain the operations of the mobile device, the host device, and the interceptor device in modification 1. Fig. Figure 10 is a conceptual diagram to explain the operations of the mobile device, the host device, and the interceptor device in modification 2. Fig. Figure 11 is a conceptual diagram to explain the operations of the mobile device, the host device, and the interceptor device in modification 5. Fig. Figure 12 is a conceptual diagram to explain the operations of the mobile device, the host device, and the interceptor device in modification 6. Fig. Figure 13 is a conceptual diagram to explain the operations of the mobile device, the host device, and the interceptor device in modification 9. FORMS OF EXECUTION OF THE INVENTION <Schematische Konfiguration von Mobilvorrichtungspositionsschätzsystem 100>

[0013] Embodiments of the present disclosure are described below with reference to the drawings. Fig. Figure 1 illustrates an example of a schematic configuration of the mobile device position estimation system. 100 of the present revelation. As in Fig. As shown in Figure 1, the mobile device position estimation system includes 100 a vehicle-mounted system 1 , which is mounted on a vehicle Hv, and a mobile device 2 , which is a communication terminal device worn by a user of the vehicle Hv.

[0014] The vehicle-mounted system 1 and the mobile device 2 are configured to perform bidirectional radio communications using radio waves in a predetermined frequency band. For example, the vehicle-mounted system 1 and the mobile device 2Configured to perform UWB-IR (Ultra Wide Band Impulse Radio) communication. That is, the vehicle-mounted system 1 and the mobile device 2 are configured to transmit and receive pulsed radio waves (hereinafter referred to as "pulse signals") used in ultra-wideband (UWB) communications. A pulse signal used in UWB communications is a signal with a very short pulse width (for example, 2 ns) and a bandwidth of 500 MHz or more (that is, an ultra-wide bandwidth).

[0015] Examples of a frequency band that can be used in UWB communication (hereinafter referred to as the UWB band) include 3.2 GHz to 10.6 GHz, 3.4 GHz to 4.8 GHz, 7.25 GHz to 10.6 GHz, and 22 GHz to 29 GHz. Of these different frequency bands, the UWB band in the present embodiment refers, by way of example, to the 3.2 GHz to 10.6 GHz band. That is, the pulse signal in this embodiment is implemented using radio waves in the 3.2 GHz to 10.6 GHz band. The frequency band used for the pulse signal can be appropriately selected according to the country in which the mobile device positioning estimation system is located. 100 is used. It may be sufficient for the pulse signal bandwidth to be 500 MHz or more, and the bandwidth can be 1.5 GHz or more.

[0016] Various modulation methods can be used for UWB-IR communication, such as pulse position modulation (PPM), which performs modulation using pulse generation positions. Specifically, on-off keying (OOK), pulse width modulation (PWM), pulse amplitude modulation (PAM), pulse code modulation (PCM), and similar methods can be employed. On-off modulation encodes information (e.g., 0 and 1) through the presence or absence of pulse signals, while pulse width modulation encodes information through pulse widths. Pulse amplitude modulation is a method for encoding information through the amplitude of the pulse signal. Pulse code modulation is a method for encoding information through a combination of pulses.

[0017] For simplicity, a communication device capable of UWB communication is referred to as a UWB communication device. UWB communication devices include not only mobile devices. 2 , but also the vehicle-mounted communication device described below 12 , which are in the vehicle-mounted system 1 It includes the mobile device. 2 is configured to send a pulse signal as a response signal when the mobile device 2 a pulse signal from the vehicle-mounted system 1 receives. Specific configurations of the vehicle-mounted system 1 and the mobile device 2 They will be described in order below. <Konfiguration von Mobilvorrichtung 2 >

[0018] First, the mobile device will be configured and operated. 2 described. The mobile device2 It can be implemented using a communication terminal device designed for different uses. For example, the mobile device 2 a smartphone. The mobile device 2 It can be an information processing device such as a tablet. The mobile device 2 It can be a device of a small rectangular type, an oval type (keychain), or a card type, conventionally known as a smart key. Furthermore, the mobile device can be 2 configured as a portable device worn on a user's finger, arm, or the like.

[0019] As in Fig. As shown in 1, the mobile device includes 2 a mobile device page reception circuit 21 , a mobile device side control unit 22 and a mobile device page send switch 23The mobile device side control unit 22 is communicable with any of the mobile device side reception circuits 21 and the mobile device page send switch 23 tied together.

[0020] The mobile device side reception circuit 21 This is a configuration for receiving pulse signals in the UWB band. When a pulse signal is received, the mobile device's side-receiving circuitry generates 21 By performing electrical processing of the signal, such as demodulation, a received signal is generated and this received signal is passed to the mobile device side control unit. 22 off. The mobile device page reception circuit 21 corresponds to a configuration for receiving radio signals from the vehicle-mounted system 1 .

[0021] If the received signal from the mobile device's side receiving circuit 21When entered, the mobile device page control unit generates 22 a baseband signal corresponding to this received signal and transmits this baseband signal to the mobile device side transmitting circuit. 23 out, where the baseband signal corresponds to a response signal. The baseband signal, which is transmitted by the mobile device side control unit 22 to the mobile device page send switch 23 The output is determined by the mobile device page send switch. 23 modulated and sent as a radio signal.

[0022] The mobile device side control unit 22 It can be implemented by a computer including a CPU, RAM, ROM, and the like. Alternatively, the mobile device's side control unit can be used. 22 It can be implemented using one or more ICs. Similarly, the mobile device side control unit can be used. 22It can be implemented using an MPU or GPU. As described later, the mobile device page send circuit is 23 A configuration that converts the baseband signal into a pulse signal and transmits the pulse signal. Accordingly, the mobile device side control unit corresponds to this. 22 a configuration that enables mobile device page sending 23 caused to send a pulse signal as a response signal when the mobile device's side-receiving circuit... 21 receives a pulse signal.

[0023] The mobile device page send switch 23 generates a transmit signal by performing electrical processing such as modulation of the baseband signal received from the mobile device side control unit. 22 The input is entered, and the transmit signal is sent via UWB communication. The mobile device's side transmit circuit. 23corresponds to a configuration for sending a response signal to the vehicle-mounted system 1 In this respect, it takes a predetermined time (hereinafter referred to as response processing time Tα) from the time the mobile device 2 the pulse signal from the vehicle-mounted system 1 It receives the pulse signal until the point at which it sends the response signal. The response processing time Tα is determined by a hardware configuration of the mobile device. 2 determined. An assumed value for the response processing time Tα can be specified in advance through testing or other means.

[0024] Furthermore, the mobile device 2The system has an active mode and a sleep mode as operating modes. The active mode is an operating mode in which processing (receiving and responding) such as generating the response signal as a reply to the signal received from the vehicle-mounted system takes place. 1 is sent, is executable. Sleep mode is an operating mode in which power consumption is reduced by stopping some or all of the functions that are enabled by the mobile device's side control unit. 22 The availability of resources is reduced. For example, sleep mode can be a mode in which the operation of a clock oscillator (not shown) is stopped. The mobile device side control unit 22 It can be configured to switch to active mode when an electrical signal corresponding to the pulse signal from the mobile device side receiving circuit is received. 21 is entered in sleep mode. <Konfiguration von fahrzeugmontierten System 1>

[0025] The configuration of the vehicle-mounted system 1 will be described next. As in Fig. As shown in 1, the vehicle-mounted system includes 1 a position estimating device 11 and several vehicle-mounted communication devices 12 The position estimating device 11 is an electronic control unit (so-called ECU: Electronic Control Unit) that performs processing to estimate the position of the mobile device 2 based on the reception states of the respective vehicle-mounted communication devices 12 of the radio signal from the mobile device 2 executes (hereinafter referred to as the position estimation processing). The position estimation device 11 is considered a computer with a CPU 111 , a flash memory 112 , a RAM 113, an I / O and bus lines that connect these configurations, configures the position estimating device 11 It can be implemented using a GPU or MPU instead of the CPU. It can also be implemented using a combination of CPU, GPU, and / or MPU.

[0026] The flash memory 112 Flash memory is a non-volatile and rewritable storage medium. 112 stores a program (hereinafter referred to as a vehicle program) to instruct the computer to act as the position estimating device 11 to function. Different non-volatile tangible storage media can be used as the specific storage medium for the vehicle program. The execution of the vehicle program by the CPU corresponds to the execution of the procedure according to the vehicle program. The flash memory 112It also stores other data, such as the mounting positions of the respective vehicle-mounted communication devices. 12 in the vehicle Hv (hereinafter referred to as communication device position data), the assumed value of the response processing time Tα at the mobile device 2 , specify assumed values ​​of vehicle device-to-vehicle device propagation times T1A and the like. The flash memory 112 This corresponds to a parameter storage unit. The assumed values ​​can be design values ​​determined through simulation, or they can be measured through actual testing.

[0027] The position estimating device 11 is compatible with each of the several vehicle-mounted communication devices 12 connected to each other, for example via a dedicated signal line. The position estimation device 11can be used with any of the several vehicle-mounted communication devices 12 They must be connected in order to communicate with each other via a communication network that is built into the vehicle.

[0028] Furthermore, the position estimation device 11 It is connected to a body ECU and / or an internal combustion engine ECU (not shown) to communicate with each other via a communication network. The body ECU is an ECU that performs various processing tasks related to vehicle body control. For example, the body ECU drives a door lock motor, which is provided at each door, based on an instruction from the position estimator. 11It locks and unlocks each door. The internal combustion engine ECU is an ECU that controls the operation of the internal combustion engine mounted on the vehicle. For example, when the internal combustion engine ECU receives a start instruction signal to instruct the engine to start from the position estimator. 11 Once this signal is received, the internal combustion engine ECU starts the internal combustion engine. For example, vehicle Hv is a vehicle connected to an internal combustion engine as its energy source, but this is not a limiting factor. Vehicle Hv can be a so-called hybrid vehicle, including both an internal combustion engine and a motor as its energy source, or an electric vehicle, including only a motor as its energy source.

[0029] The vehicle-mounted communication devices 12 are communication devices for performing radio communication (here UWB communication) with the mobile device 2The operation of each vehicle-mounted communication device 12 is provided by the position estimation device 11 controlled. Each of the multiple vehicle-mounted communication devices 12 is configured to use UWB communication with other vehicle-mounted communication devices 12 to be able to execute, which are also mounted on the vehicle Hv. That is, any vehicle-mounted communication device. 12 is configured to communicate wirelessly with the mobile device 2 and other vehicle-mounted communication devices 12 to be able to execute. It may be sufficient that the number of vehicle-mounted communication devices 12 , which are in the vehicle-mounted system 1 Included are at least three. At least one of the several vehicle-mounted communication devices. 12is preferably located in the vehicle interior of the vehicle Hv. Each vehicle-mounted communication device 12 is preferably positioned where it can see through both the interior and exterior of the vehicle interior.

[0030] The vehicle-mounted system 1 The present embodiment includes a right-side communication device. 12A , a left-sided communication device 12B , a rear-side communication device 12C and a front-facing communication device 12X than the vehicle-mounted communication devices 12 The right-side communication device 12A For example, it is located in the C-pillar on the right side of the vehicle. The C-pillar is the third pillar when viewed from the front. The communication device is on the left side. 12BFor example, it is located in the C-pillar on the left side of the vehicle. The rear communication device 12C It is located at the upper end of the rear window. The front communication device 12X is located on an overhead console.

[0031] Each vehicle-mounted communication device 12The device is preferably positioned where it has a good view through both the interior and exterior of the vehicle interior. The reason for this is as follows. First, there is a premise that radio waves used in UWB communication are easily reflected (in other words, shielded) by metal, and therefore a shielding object causes the radio wave to propagate while being diffracted. In a configuration where distance measurement is performed using the propagation time of radio waves, as in the present embodiment, a distance error due to diffraction can occur. Furthermore, to determine the propagation time of the radio wave, it is necessary to receive the signal transmitted by another UWB communication device, and in this case, diffraction by the shielding object significantly reduces the radio wave strength.That is to say, in a configuration where the distance is measured using the propagation time of radio waves as in the present embodiment, a preferred configuration is one that allows signals transmitted by other UWB communication devices to be received normally rather than allowing attenuation of radio wave strength due to diffraction.

[0032] With regard to the foregoing, it is preferred that each vehicle-mounted communication device 12It is mounted in a position where it has a good view both inside and outside the vehicle. Positions that allow for a good view both inside and outside the vehicle include the ceiling or sky of the vehicle interior and various pillars (especially the part at window height). That is to say, the arrangement of the vehicle-mounted communication devices. 12 as described above corresponds to an example of the arrangement in which each vehicle-mounted communication device 12 is in a position that makes it easier to see through the interior and exterior of the vehicle.

[0033] The installation mode (especially the installation position and the number of devices installed) of the vehicle-mounted communication devices 12is not limited to the mode described above. For example, the right-side communication device 12A It should be located near the A-pillar on the right side of the vehicle or near the outer door handle on the front passenger door. The left-side communication device 12B It can alternatively be located on the A-pillar on the left side of the vehicle or on the outer door handle on the front door. The outer door handle refers to a gripping element (so-called door handle) provided on the outer surface of the door for opening and closing the door. The area near the outer door handle includes the inner part of the outer door handle.

[0034] Another mode is the front-facing communication device 12X It should be located in a central section of the vehicle interior ceiling. The front communication device12X It can be located on the central section of the instrument panel in the width direction of the vehicle or near the center console box. Although only a front-facing communication device 12X As shown in the drawings, more than one front-facing communication device is possible. 12X be provided in the vehicle interior.

[0035] The vehicle-mounted communication device 12 It can be located on the B-pillar of the vehicle. Of course, it can also be located on the outer surface of the A-pillar or D-pillar. Furthermore, the vehicle-mounted communication device can... 12 It should be located near a boundary (hereinafter referred to as an upper end section of the side surface) between a side surface section of the vehicle Hv and a roof section. Such a configuration corresponds to a configuration in which the vehicle-mounted communication device 12is arranged on a frame section located on an upper side section of the side window. The upper end section of the side surface corresponds to a roof section of the vehicle Hv, where an upper end section of the vehicle Hv's door is in contact with the vehicle Hv's roof. The vehicle-mounted system 1 This can also include a vehicle-mounted communication device 12 It includes a communication area within the trunk. The vehicle-mounted system 1 This can also be a vehicle-mounted communication device 12 including, which is located on an exterior surface section of the vehicle Hv. The exterior surface section now referred to is a body section that is in contact with a space that is external to the vehicle cabin of the vehicle Hv, and includes a side surface, a rear surface and a front surface of the vehicle Hv.

[0036] The mounting position of each vehicle-mounted communication device 12 In the vehicle Hv, for example, it can be represented as a point in a two-dimensional coordinate system (hereinafter referred to as a two-dimensional vehicle coordinate system) that has its center at an arbitrarily selected position in the vehicle Hv and that is parallel to a horizontal vehicle plane. The horizontal vehicle plane is a plane orthogonal to the vehicle's vertical direction. The X-axis forming the two-dimensional vehicle coordinate system can be parallel to the front-to-rear direction of the vehicle, and the Y-axis can be parallel to the vehicle's width direction. The center of the two-dimensional coordinate system can, for example, be the center of the rear axle. The communication device position data, which specifies the mounting position of each vehicle-mounted communication device, 12They are stored in the flash memory. 112 stored. In the present embodiment, any vehicle-mounted communication device is considered a preferred mode. 12 Each communication device is assigned a unique number. These numbers serve as information for identifying the multiple vehicle-mounted communication devices. 12 In the flash memory 112 are the position of each vehicle-mounted communication device 12 and their communication device numbers, which are linked together and stored as the communication device position data.

[0037] Each of the several vehicle-mounted communication devices 12 includes a control IC 31 , a transmitting circuit 32 and a receiving circuit 33 , as in Fig. 2 is shown. The control IC 31 is with each of the transmission circuits32 and the receiving circuit 33 connected. Furthermore, the control IC is 31 furthermore with the position estimation device 11 connected so that they can communicate with each other. The control IC 31 instructs the transmitter circuit 32 the baseband signal that is received by the position estimator 11 The input is processed and causes it to be sent wirelessly. The control IC 31 provides the data received by the receiving circuit 33 to be received, to the position estimating device 11 Details of the control IC 31 will be described later.

[0038] The transmission circuit 32 generates a pulse signal by performing electrical processing of the baseband signal provided by the control IC 31 The system inputs parameters such as modulation and the like, causing this pulse signal to be emitted as a radio wave. The transmitting circuit... 32for example, using a modulation circuit 321 and a transmitting antenna 322 implemented.

[0039] The modulation circuit 321 is a circuit that modulates the baseband signal supplied by the control IC 31 is entered. The modulation circuit 321 generates a modulation signal according to the data specified by the baseband signal provided by the position estimating device. 11 (hereinafter referred to as transmission data) is entered, and it is sent to the transmitting antenna. 322 The modulation signal is a signal obtained by modulating the transmitted data using a predetermined modulation method (for example, PCM modulation). The modulation signal is a signal sequence in which several pulse signals are arranged to create time intervals corresponding to the transmitted data.

[0040] The modulation circuit 321It includes a circuit that generates an electrical pulse signal (hereinafter referred to as a pulse generation circuit) and a circuit that amplifies and shapes the pulse signal. The transmitting antenna 322 is a configuration that uses the electrical pulse signals generated by the modulation circuit 321 The signal is emitted, converted into radio waves, and radiated into space. That is, the transmitting antenna. 322 It emits a pulsed radio wave with a predetermined bandwidth in the UWB band as a pulse signal. The modulation circuit outputs... 321 the electrical pulse signal to the transmitting antenna 322 The modulation circuit outputs... 321 a signal (hereinafter referred to as a transmission message signal) to the control IC 31 off, which indicates that the pulse signal has been output, so that the modulation circuit 321simultaneously outputs the electrical pulse signal and the signal indicating that the pulse signal has been output.

[0041] The transmission circuit 32 The present embodiment is configured such that the rise time of the pulse signal is one nanosecond. The rise time is the time required from when the signal strength first exceeds 10% of the maximum amplitude until it exceeds 90% of the maximum amplitude. The rise time of the pulse signal is determined by the hardware configuration, such as the circuit configuration of the transmitting circuit. 32 The rise time of the pulse signal can be specified through simulation and / or actual testing. Generally, the rise time of the pulse signal in the UWB band is approximately 1 nanosecond.

[0042] The receiving circuit 33is a configuration that receives radio signals that comply with the communication standards defined in the mobile device position estimation system 100 can be used, such as a pulse signal that serves as a response signal from the mobile device 2 is transmitted. The receiving circuit 33 includes, for example, a receiving antenna 331 and a demodulation circuit 332 The receiving antenna 331 It is an antenna for receiving a pulse signal. The receiving antenna 331 indicates the demodulation circuit 332 an electrical pulse signal corresponding to the pulse signal generated by the mobile device 2 is being sent.

[0043] If the receiving antenna 331 The demodulation circuit receives the pulse signal in the UWB band. 332Electrical processing of this signal, such as demodulation, to generate a received signal, and outputs the received signal to the position estimation device. 11 off. That is, the demodulation circuit 332 is a configuration that demodulates a series of modulation signals (hereinafter referred to as pulse series signals) that have multiple pulse signals supplied by the mobile device 2 and / or other vehicle-mounted communication devices 12 are sent, and in doing so, restores the data that was previously modulated. For example, the demodulation circuit obtains 332 based on the pulse signals emitted by the receiving antenna 331 The pulse series signal, which is generated by the mobile device, is entered. 2 or another vehicle-mounted communication device 12 is being sent.

[0044] The pulse series signal generated by the demodulation circuit332 The signal obtained is such that it consists of several pulse signals originating from the receiving antenna. 331 The inputs must be arranged in chronological order to reflect actual reception intervals. The demodulation circuit 332 includes a frequency conversion circuit that converts the frequency of the pulse signals received by the receiving antenna. 331 It is received, converted into a baseband signal, and output to an amplifier circuit that amplifies the signal level, and so on. Furthermore, when the pulse signal is received from the receiving antenna... 331 The input is sent to the receiving circuit. 33 a signal indicating that the pulse signal has been received (hereinafter referred to as a receive notification signal) to the control IC 31 out of.

[0045] This involves the vehicle-mounted communication device. 12 as an antenna for transmitting (that is, the transmitting antenna) 322) and an antenna for receiving (that is, the receiving antenna) 331 ) including illustrated. However, it can be configured for both transmitting and receiving, to use a single antenna element with a directional coupler. The modulation circuit 321 and the demodulation circuit 332 can be in the control IC 31 be installed. That is, the vehicle-mounted communication device. 12 It can be implemented using a single antenna and a single dedicated IC with different circuit functions. <Funktion von Steuer-IC 31 >

[0046] The control IC 31 , which is in the vehicle-mounted communication device 12 The present embodiment includes controls the operating mode of the vehicle-mounted communication device. 12 based on the instructions from the position estimating device11 The vehicle-mounted communication device 12 This embodiment includes a host mode and an intercept mode as its operating modes. The host mode is the operating mode in which the transmission of pulse signals is permitted (in other words, the right to transmit pulse signals is granted). The host mode corresponds to the operating mode in which radio communication with other UWB communication devices, including the mobile device, is possible. 2 are executable. The interception mode is the operating mode in which only the reception of pulse signals from the mobile device is possible. 2 and another vehicle-mounted communication device 12 The process is executed. That is, interception mode is the operational mode for detecting the pulse signal transmitted by the mobile device. 2 and another vehicle-mounted communication device 12is transmitted. From another perspective, the interception mode corresponds to an operating mode in which the transmission of pulse signals is prohibited (that is, there is no right to transmit).

[0047] Whether a particular vehicle-mounted communication device 12 Operating in host mode or intercept mode, the position estimation device 11 controlled. That is, the control IC 31 The operating mode is switched based on the control signal received from the position estimator. 11 The following is entered. For the sake of simplicity, the vehicle-mounted communication device is described below. 12 , which operates in host mode, referred to as the host device, and the vehicle-mounted communication device 12 The device operating in interception mode is called the interceptor. The host device corresponds to a transceiver.

[0048] The control IC31 It performs a round-trip time measurement and a pulse-receive interval measurement using a clock signal input from a clock oscillator (not shown in the drawings). The round-trip time measurement measures the round-trip time Tp, which is a duration of when the transmit circuit 32 the pulse signal is sent until the receiving circuit 33 The pulse signal is received. The pulse reception interval measurement processing measures the pulse reception interval Tq, which is a time duration when the receiving circuit is... 33 a pulse signal is received until the receiving circuit... 33 It receives another impulse signal.

[0049] The measurement of the orbital period Tp and the pulse reception interval Tq can be performed by counting a clock signal input from a clock oscillator, which is not shown in the drawings. For example, in host mode, when the control IC 31through the position estimation device 11 The control IC is instructed to perform the measurement of the orbital period Tp. 31 The cycle time measurement processing is disabled. In interception mode, when the control IC 31 through the position estimation device 11 When instructed to perform the measurement of the pulse reception interval Tq, the control IC executes 31 The pulse reception interval measurement processing. The timing of the pulse signal transmission by the transmitting circuit. 32 can be done using the input of the transmission message signal from the transmitting circuit 32 The timing of the pulse signal reception by the receiving circuit can be determined. 33 can be done using the input of the received message signal from the receiving circuit 33 to be determined. Furthermore, the tax IC 31 configured to operate based on instructions from the position estimator 11Bidirectional radio communications with a given other vehicle-mounted communication device 12 to execute. <Funktion von Positionsschätzvorrichtung 11 >

[0050] The position estimating device 11 includes a vehicle information acquisition unit F1 , a role definition unit F2 and a position estimation unit F3 , as in Fig. Figure 3 shows functions implemented by the CPU, which executes the vehicle program stored in the flash memory. 112 is stored. Some or all of the different functional blocks that are used by the position estimator. 11Functional blocks that are intended to be implemented can be provided as hardware. A mode in which a specific function is implemented as hardware also includes a mode in which the specific function is implemented using one or more integrated circuits (ICs). Furthermore, some or all of the functional blocks can be implemented through cooperation between software execution by the CPU or similar and the hardware configuration.

[0051] The vehicle information acquisition unit F1The system obtains various pieces of information indicating the vehicle's state (hereinafter referred to as vehicle information) from sensors, switches, etc., installed in the vehicle. Vehicle information includes, for example, the open / closed state of the doors, the locked / unlocked state of each door, the gear position detected by the gear position sensor, the vehicle's power state (e.g., ignition on / off), the parking brake operation state, etc. The types of information included in the vehicle information are not limited to those described above. The readings from the brake sensor, which detects whether the brake pedal (not shown in the drawings) is depressed or not, are also included in the vehicle information.

[0052] The vehicle information acquisition unit F1The vehicle information acquisition unit (VIN) determines the current state of the vehicle based on various pieces of information described above. For example, if the internal combustion engine is off and all doors are locked, the VIN determines... F1 that the vehicle Hv is parked. It goes without saying that the conditions for determining that the vehicle Hv is parked can be designed according to different aspects, and different determination conditions can be applied.

[0053] The role assignment unit F2 controls the operating mode of each vehicle-mounted communication device 12 The role assignment unit F2 causes any of the several vehicle-mounted communication devices 12, to operate as the host device, and to reset all others to operate as the interceptors. As an example, the role-setting unit causes F2 in this embodiment the front-side communication device 12X , as the host device to operate while it operates the right-side communication device 12A , the left-sided communication device 12B and the rear communication device 12 instructs the intercepting devices to operate. Instructing the host device to operate is equivalent to instructing it to operate in host mode, that is, assigning it a role to communicate with the mobile device. 2 . Likewise, causing the intercepting device to operate is equivalent to causing it to operate in intercepting mode.

[0054] Fig. Figure 4 is a conceptual representation of the flow of radio signals between the different configurations used by the mobile device position estimation system. 100 will be provided when the aforementioned role specifications are implemented. Since the front-end communication device 12X When the host device operates, radio communication with the mobile device is established. 2 through the front-facing communication device 12X executed. That is, the position estimation device 11 causes a pulse signal (actually a pulse serial signal indicating multiple bit sequences) to be sent from the front-side communication device. 12X for mobile device 2 is sent. If the mobile device 2 Upon receiving the pulse signal from the host device, it sends a pulse signal as a response signal. The pulse signal received by the mobile device... 2The data is transmitted through the front-end communication device. 12X received, which acts as the host device. The pulse signal, which is transmitted by the front-side communication device. 12X is sent, which acts as the host device, and the pulse signal that is transmitted by the mobile device 2 as the response signal is sent, each of the intercepting devices, such as the right-side communication device, will be detected. 12A , which act as the intercepting devices, receive, as shown by the dashed line in the drawing.

[0055] The position estimation unit F3 is a configuration that performs position estimation processing. Position estimation processing is performed using the [missing information - likely a specific parameter or feature]. Fig. The flowchart shown in section 5 describes the position estimation processing in this embodiment, which includes steps 5. S101 until S108As an example, each step is primarily determined by the position estimation unit. F3 executed.

[0056] Position estimation processing can be performed periodically (for example, every 200 milliseconds) at a predetermined interval while the vehicle is, for example, parked. Position estimation processing can also be configured to run at a predetermined interval, provided that processing for authenticating the mobile device is required. 2 through cryptographic communication with the mobile device 2 is successful. The authentication of the mobile device. 2 This can be carried out, for example, using a challenge-response procedure. Successful authentication corresponds to the determination that the communication partner of the vehicle-mounted system is authorized. 1 an associated mobile device 2 is.

[0057] The first step is S101 An instruction to prepare for the measurement of the orbital period Tp is sent to the host device. In response, the host device switches to a state in which it is ready to measure the orbital period Tp. The state of readiness to measure the orbital period Tp is the state in which, when the next pulse signal is sent, the measurement of the orbital period Tp is started. At step S102 An instruction to prepare for the measurement of the pulse reception interval Tq is sent to each interceptor. In response, each interceptor switches to a state in which it is ready to measure the pulse reception interval Tq. The state of readiness to measure the pulse reception interval Tq is the state in which, when the next pulse signal is received, the measurement of the pulse reception interval Tq is initiated.

[0058] In step S103An instruction is given to send a pulse signal to the host device. Based on this instruction, the host device sends the pulse signal to the mobile device. 2 and starts measuring the orbital period Tp. Afterwards, the host device releases the mobile device from receiving the pulse signal. 2 This indicates that the host device has finished measuring the orbital period Tp. The interceptor then receives the pulse signal from the mobile device. 2 This also triggers the intercepting device to terminate the measurement of the pulse reception interval Tq. The pulse reception interval Tq corresponds to a signal reception interval. The intercepting device is preferably configured to identify whether the source of the received pulse signal is the host device or the mobile device. 2 is, through the frequency band of the signal, a code that is contained in the signal, or the like.

[0059] At step S104 The orbital period Tp is determined by the front-end communication device. 12X obtained, which acts as the host device. At step S105 is based on the orbital period Tp, the first propagation time T12 , which determines the propagation time of the pulse signal from the front-side communication device 12X for mobile device 2 is calculated. Based on the initial propagation time T12 The distance from the host device to the mobile device is determined. 2 Estimated. In particular, the one-way signal propagation time is estimated by subtracting the assumed value of the response processing time Tα at the mobile device. 2 The one-way signal propagation time from the host device to the mobile device is calculated from the round-trip time Tp and then divided by 2. 2 corresponds to an initial spreading time T12The signal propagation time corresponds to the propagation time of a radio signal. The distance from the front-end communication device 12X , which acts as the host device, to the mobile device 2 This is then calculated by multiplying the first propagation time. T12 calculated using the propagation speed of radio waves in air. Step S105 corresponds to a first propagation time determination unit.

[0060] At step S106 The pulse reception intervals Tq are obtained from the respective intercepting devices. At step S107 The second propagation time T2A for each interceptor is estimated based on the pulse reception interval Tq and the orbital period Tp observed by that interceptor. The second propagation time T2A for a given interceptor corresponds to the signal travel time of the pulse signal received by the mobile device. 2is sent, is needed to disconnect from the mobile device 2 to spread out to this specific interceptor. Then the distance from each interceptor to the mobile device is 2 calculated by multiplying the second propagation time T2A for each interceptor by the propagation speed of the radio wave. Step S107 corresponds to a second unit for determining the time of propagation.

[0061] Fig. 6 and Fig. 7 are now used to establish a relationship between the orbital period Tp and the pulse reception interval Tq, which is measured at an intercepting device (for example, a right-side communication device). 12A) is observed, and the feasibility of calculating the propagation time of the signal (and thus the distance) from the mobile device 2 to explain this intercepting device based on the orbital period Tp and the pulse reception interval Tq. Fig. 6 and Fig. Figure 7 conceptually shows the operations in a single position estimation processing of the front-side communication device. 12X , which acts as the host device, the right-side communication device 12A , which acts as the interceptor, and the mobile device 2 .

[0062] T12 in the drawing denotes the duration of the pulse signal transmitted by the front-side communication device. 12X is sent, is needed to connect to the mobile device 2 to propagate (that is, the initial propagation time); T21 denotes the signal travel time of the pulse signal passing through the mobile device 2 is sent, is needed to connect to the front-end communication device. 12X to propagate. Since the propagation time of the pulse signal from the front-end communication device 12X for mobile device 2A relationship that can be considered the same for the outward and return journeys is T12 = T21 is given. T1A denotes the signal propagation time (hereinafter referred to as the vehicle device-to-vehicle device propagation time) of the pulse signal passing through the front-end communication device. 12X is sent, is needed to connect to the right-side communication device 12A to propagate. T2A denotes the signal propagation time (that is, the second propagation time) of the pulse signal transmitted by the mobile device. 2 is sent, is needed to connect to the right-side communication device 12A to spread out.

[0063] The orbital period Tp is equal to the sum of: the time T12 , which is caused by the pulse signal transmitted by the front-side communication device 12X is sent, is needed to connect to the mobile device 2to spread; the response processing time Tα on the mobile device 2 ; and the time that the pulse signal, which is transmitted by the mobile device 2 is sent, is needed to connect to the front-end communication device. 12X to spread out. That is, the relationship Tp = T12 + T21 + Tα is established. Therefore, the first spreading time is T12 The response processing time Tp, observed by the host device, can be determined by inserting it into the following expression 1. The assumed value stored in the flash memory can be considered the response processing time. 112 is registered, applied. The response processing time Tα can be the actual value provided by the mobile device. 2 The measurement is applied as described separately below as modification 1. T12 = ( Tp − T α ) / 2

[0064] Next, a method for calculating the second propagation time T2A is described. The value obtained by summing the second propagation time T2A and the first propagation time T12 and the response processing time Tα at the mobile device 2 The given value is equal to the value obtained by summing the pulse reception interval Tq and the vehicle-to-vehicle-device propagation time T1A. Therefore, the second propagation time T2A can be determined by the following expression 2. T2A = Tq + T1A − ( T12 + T α ) = Tq + T1A − Tp / 2 + T α / 2

[0065] That is, as shown in the preceding expression 2, the second propagation time T2A, which can be used as an indicator of the distance from the mobile device 2 to the right-hand communication device 12AThis is calculated based on the pulse reception interval Tq, the round-trip time Tp, the vehicle-to-vehicle device propagation time T1A, and the response processing time Tα. That is, the preceding expression 2 shows that the second propagation time T2A is calculated using the first propagation time. T12 can be calculated.

[0066] Here, the vehicle-to-vehicle propagation time T1A is a parameter that depends on the distance from the front communication device. 12X to the right-hand communication device 12A is determined. Since the distance from the front communication device 12X to the right-hand communication device 12A Since the vehicle device-to-vehicle device propagation time T1A is constant, it is generally constant. The flash memory 112The present embodiment stores the assumed value of the vehicle device-to-vehicle device propagation time T1A, as described above.

[0067] The position estimation unit F3 The second propagation time T2A is calculated by inserting the orbital period Tp, the pulse reception interval Tq and various parameters stored in the flash memory. 112 are stored in expression 2. Then the position estimation unit is calculated. F3 the distance from the mobile device 2 to the right-hand communication device 12A by multiplying the second propagation time T2A, which is determined by the above, by the propagation speed of the radio waves in air.

[0068] The above example describes a method for calculating the second propagation time T2A and the distance from the right-hand communication device. 12A for mobile device2 based on the orbital period Tp and the pulse reception interval Tq, which is located at the right-side communication device 12A The observed phenomenon is described. Similarly, the second propagation time T2A and the distance (that is, the distance between the interceptor and the mobile device) from another interceptor to the mobile device are described. 2 calculated from the pulse reception interval Tq and the orbital period Tp, which is observed at the intercepting device.

[0069] According to Fig. 5, when calculating the distances from the respective intercepting devices to the mobile device 2 at step S107 Once completed, step S108 executed at step S108 will determine the position of the mobile device 2 regarding the vehicle based on the distances to the mobile device 2The distance from the host device to the respective intercepting devices (i.e., from the respective vehicle-mounted communication devices) and the mounting positions of the respective vehicle-mounted communication devices is estimated. 2 is from the first spread period T12 derived and the distance from the intercepting device to the mobile device 2 is derived from the second propagation time T2A. Therefore, estimating the position of the mobile device corresponds to 2 based on the distances from the vehicle-mounted communication devices to the mobile device 2 Estimating the position of the mobile device 2 based on the first propagation time and the second propagation time T2A for each interceptor.

[0070] As a method for calculating the position of the mobile device 2using the position of each vehicle-mounted communication device and information about the distances from each vehicle-mounted communication device to the mobile device 2 A calculation algorithm can be used that is employed in satellite positioning systems or similar systems. The position of the mobile device 2 With regard to the vehicle Hv, it can be represented as a point in a two-dimensional coordinate system parallel to the road surface plane (that is, the two-dimensional vehicle coordinate system).

[0071] The position of the mobile device 2 can be based on the distances of at least three vehicle-mounted communication devices 12 and the positions of these three vehicle-mounted communication devices 12 be appreciated.

[0072] How conceptually in Fig. As shown in section 8, the position of the mobile device corresponds to 2 the coordinates of an intersection point of circles (or spheres) that are used for the respective vehicle-mounted communication devices 12 are drawn, with each circle having its center at the mounting position of this vehicle-mounted communication device. 12 has and its radius is the estimated distance from this vehicle-mounted communication device 12 for mobile device 2 is. The circle Cx, which is represented as a solid line in Fig. Figure 8 shows a circle with radius Rx and its center at the front communication device. 12X The radius Rx is the estimated distance from the front-end communication device. 12X for mobile device 2The circle Ca, shown by a single dotted line, denotes a circle with radius Ra and its center at the right-hand communication device. 12A The radius Ra is the estimated distance from the right-hand communication device. 12A for mobile device 2 The circle Cb, indicated by a double-dotted line, denotes a circle with radius Rb and its center at the left-hand communication device. 12B The radius Rb is the estimated distance from the left-hand communication device. 12B for mobile device 2 The dotted line Cc denotes a circle with radius Rc and its center at the rear communication device. 12C The radius Rc is the estimated distance from the rear communication device. 12C for mobile device 2 fixed. The point Pm in Fig. 8 denotes the position of the mobile device 2 The position of the mobile device 2 It can be at the point where the distances from the respective circle are minimal. <Zusammenfassung von Ausführungsform>

[0073] In the embodiment mentioned above, the front-side communication device transmits 12X , which acts as the host device, sends the pulse signal for position estimation to the mobile device 2 and the mobile device 2 The pulse signal is sent as a response signal to the pulse signal sent by the host device. The host device measures the orbital period Tp and reports it to the position estimator. 11 , where the cycle time Tp is the time from sending the pulse signal to the mobile device 2 until it is received by the receiving circuit 33 of the pulse signal. The vehicle-mounted communication device12 (that is, the intercepting device) with the exception of the host device measures and reports to the position estimating device 11 the pulse reception interval Tq, which is from the time it receives the pulse signal sent by the host device until the time it receives the pulse signal sent by the mobile device 2 is sent. Then the position estimator calculates. 11 (in other words) estimates the position of the mobile device 2 regarding the vehicle Hv based on a revolution time and several pulse reception intervals Tq, which are observed at respective intercepting devices.

[0074] According to this configuration, the position of the mobile device can be 2 by a single sending and receiving of signals between the vehicle-mounted system 1 and the mobile device 2be appreciated. In other words, there is no need for multiple vehicle-mounted communication devices. 12 individual radio communication with the mobile device 2 execute. Accordingly, the mobile device position estimation system, which determines the position of the mobile device, can be used. 2 Regarding the vehicle Hv, based on the propagation time of the radio signal, estimates the number of times radio communications with the mobile device occur. 2 The process used for position estimation will be limited.

[0075] The embodiment of the present disclosure has been described above. The present disclosure is not intended to be limited to the above embodiment, but has a technical scope that covers different modifications described below, and can likewise be implemented with different changes not described below without departing from the spirit and scope of the present disclosure. For example, different modifications described below can be implemented in combination to a reasonable extent that does not cause technical inconsistency. It should be noted that sections having the same functions as those in the above embodiment are designated with the same reference numerals, and their description is omitted.In a case where only part of the configuration is described, the preceding embodiment is applicable to the remaining part of the configuration. <Modifikation 1>

[0076] In the embodiment described above, a design value is stored in the flash memory. 112 The pre-registered value (in other words, the assumed value) is used as the response processing time Tα, but this is not limiting. The mobile device 2 can be configured to measure the response processing time required when the mobile device is connected, using a timer not shown in the drawings. 2 receives the signal from the host device until, when the mobile device 2 the response signal is sent as a response, and the measured response processing time Tα is sent to the host device via radio communication.

[0077] As in Fig. As shown in 9, the response processing time Tα, which is determined by the mobile device, can be 2 The measurement is communicated via data communication that is separate from the pulse signal Ps used for position estimation. For example, the mobile device 2 configured to send a pulse series signal (hereinafter referred to as the processing time message signal Sg) that indicates the actual measured value of the response processing time Tα (in other words, the actual processing time) at a time when a predetermined time has elapsed since the pulse signal used for position estimation was sent. If the actual response processing time Tα can be represented by a single pulse signal, the mobile device can 2 be configured to send the pulse signal in the position estimation processing that indicates the actual response processing time Tα.

[0078] If the host device of the present modification receives the processing time message signal from the mobile device 2 The host device receives and supplies the position estimating device. 11 with data indicating the actual measured value of the response processing time specified in the received processing time message signal Sg. If the position estimating device 11 The device stores the actual measured value of the response processing time obtained from the host device. 11 the data in the RAM 113 and uses them to delay the initial spread T12 and to calculate the second propagation time T2A for each interceptor. In this configuration, the RAM corresponds to... 113 a response processing time retention unit.

[0079] According to the configuration disclosed in Modification 1, the vehicle-mounted system can 1a distance from any vehicle-mounted communication device 12 for mobile device 2 using the actual response processing time Tα of the mobile device 2 Calculate. According to this configuration, the accuracy for estimating the distance from any vehicle-mounted communication device can be increased. 12 for mobile device 2 to be improved. Furthermore, the response processing time Tα of the mobile device must be improved. 2 not be constant, thus limiting the software extensibility of the mobile device 2 is increased. (Modification 2)

[0080] The role assignment unit F2 , which are determined by the position estimation device 11 It is intended to be configured to dynamically control the vehicle-mounted communication device. 12 to change the device that operates as the host device, as in Fig. As shown in 10. For example, each time the position estimation processing is executed, the role assignment unit can F2 be configured to use the vehicle-mounted communication device 12 , which acts as the host device, in the order of the front-end communication device 12X , the right-hand communication device 12A , the left-sided communication device 12B and the rear communication device 12C to change (in other words, replace). This configuration is equivalent to a configuration in which the host device is changed in rotation.

[0081] According to this type of configuration, even if there is a malfunction in the front communication device. 12X occurs, as long as another vehicle-mounted communication device is present 12 operated normally, the position of the mobile device 2can be estimated by using the standard vehicle-mounted communication device 12 is caused to operate as the host device. That is, it can increase the robustness of the mobile device position estimation system.

[0082] An alternative configuration could be such that a position obtained by averaging the results of multiple position estimation processes performed while the host device is being modified is used as the current position of the mobile device. 2 is used. Since the positions of the respective vehicle-mounted communication devices 12 Since they differ, the change in the vehicle-mounted communication device 12, which acts as the host device, determines the degree of multipath influence on the orbital period Tp and the pulse reception interval Tq. Therefore, this configuration can reduce the influence of multipath interference caused by the environment around the vehicle Hv. (Modification 3)

[0083] In the embodiment described above, the design value (in other words, the assumed value) stored in the flash memory 112 The vehicle-to-vehicle propagation time T1A is registered as the time used from the host device to the interceptor, although this is not a limitation. The vehicle-to-vehicle propagation time T1A can be a value measured by actually performing radio communication between the host device and each interceptor with a predetermined timing (that is, an actually measured value).

[0084] For example, the position estimating device selects 11 The intercepting device, which is a measurement target (hereinafter referred to as the measurement target device), selects from among several intercepting devices and operates the measurement target device in an operating mode in which the measurement target device sends a pulse signal as a response signal when the measurement target device receives a pulse signal from the host device. Then the position estimating device 11 the host device to send the pulse signal to the measurement target intercept device.

[0085] When the target interceptor receives the pulse signal from the host device, it transmits the pulse signal as the response signal. The host device obtains the time between transmitting the pulse signal and receiving it from the target interceptor (i.e., the round-trip time). The value obtained by subtracting the response processing time at the target device from the round-trip time obtained through the preceding processing, and then dividing by 2, is the vehicle device-to-vehicle device propagation time T1A from the host device to the target device. This calculation can be performed, for example, by the position estimation unit. F3 The process can be executed. A predetermined value can be applied as the response processing time of the target device.

[0086] When the vehicle's power supply is switched off for driving, or when the gear selector is set to the park position, or similar, radio communication for measuring the vehicle-to-vehicle propagation time T1A can be performed, for example, as a preparatory operation for position estimation processing. The measurement target device can be changed sequentially. That is, radio communication for measuring the vehicle-to-vehicle propagation time T1A can be performed for any combination of vehicle-mounted communication devices. 12 The radio communication for determining the vehicle-to-vehicle-device propagation time T1A can be performed periodically with a predetermined cycle, independently of the position estimation processing. <Modifikation 4>

[0087] Regarding the foregoing modification 3, the position estimation device 11determine whether the vehicle-mounted communication device 12 is mounted at a predetermined position of the vehicle, based on the vehicle device-to-vehicle device propagation time T1A, which is obtained by establishing bidirectional radio communication between the vehicle-mounted communication devices 12 is executed. Determine whether the vehicle-mounted communication device 12 The determination of whether a communication module has been completely removed from the vehicle Hv to determine whether it is mounted at the predetermined position in the vehicle corresponds to determining whether the vehicle-mounted communication device is installed at the predetermined position in the vehicle. 12 to remove the vehicle's high voltage (Hv) and whether there is an occurrence of a baseband signal relay attack.

[0088] If the vehicle-mounted communication device 12If the vehicle Hv has been moved away and there is no occurrence of the baseband signal relay attack, this corresponds to an increase in the distance between the vehicle-mounted communication devices. 12 Therefore, the vehicle-to-vehicle-device propagation time T1A is relatively long in this case. On the other hand, if the vehicle-mounted communication device 12 When normally installed in the vehicle, the vehicle-to-vehicle propagation time T1A is expected to be within a certain range. Therefore, if the vehicle-to-vehicle propagation time T1A, determined by actual radio communication between the vehicle-mounted communication devices, 12 If the measured value is outside the predetermined normal range, this indicates a probability that the vehicle-mounted communication devices 12from the vehicle Hv and there is an occurrence of the baseband signal relay attack. The normal range of the vehicle device-to-vehicle device propagation time T1A can be specified in advance by testing and / or other means and can be stored in the flash memory. 112 be registered. The lower limit of the normal range can be appropriately set, for example, to 0 seconds. The normal range can be defined only by the upper limit. The upper limit of the normal range can be set to a level such as 33 nanoseconds, which is assumed not to be observed when the vehicle-mounted communication device is in operation. 12 attached to the vehicle Hv. 33 Nanoseconds are a length that indicates the distance between the vehicle-mounted communication devices 12 It is approximately 10 meters.

[0089] For example, while the vehicle Hv is in the parked state, the position estimation device initiates 11 The present modification periodically synchronizes the vehicle-mounted communication devices for each combination of vehicle-mounted communication devices that have a positional relationship to each other that enables the radio communications to be carried out, thereby increasing the vehicle-device-to-vehicle-device propagation time T1A for each combination of the vehicle-mounted communication devices. 12is obtained. Then it is determined whether these vehicle-to-vehicle device propagation times T1A are within the normal range. If, among the multiple vehicle-to-vehicle device propagation times T1A, there is a vehicle-to-vehicle device propagation time T1A that deviates from the normal range, it can be determined that the vehicle-to-vehicle communication device 12 , which is located in the vehicle Hv, has been completely removed from the vehicle Hv by removing the communication module, and that the relay attack is carried out at the baseband signal level.

[0090] If it is determined that the aforementioned relay action (so-called relay attack) is taking place, the position estimation device prohibits 11For example, the operation of the electronic vehicle key system. The electronic vehicle key system referred to here is a system in which the vehicle-mounted system 1 and the mobile device 2 communicate wirelessly with each other using radio waves in a predetermined frequency band, so that the vehicle-mounted system 1 the mobile device 2 It authenticates the vehicle and executes predetermined vehicle control actions such as unlocking the doors and starting the engine. The electronic vehicle key system corresponds to a so-called smart entry system.

[0091] If the position estimating device 11 Determined that the aforementioned relay action will take place, the position estimating device can 11be configured to cooperate with a wide area communication device, not shown in the drawings, to exchange contact information (e.g., telephone number or email address of a user or security company) pre-stored in flash memory 112 were registered to provide emergency contact information. The term "wide area communication device" refers to a communication device for wireless access to a public communications network provided by a telecommunications provider, such as a mobile network or the internet.

[0092] According to the foregoing configuration, disclosed as the present modification, it is possible to suppress the illegal use of the vehicle's high-voltage transmission, even if the vehicle-mounted communication device is... 12, which is located in the vehicle Hv, is completely removed from the vehicle Hv by removing the module and the baseband signal level relay attack takes place. <Modifikation 5>

[0093] The signal sent and received for position estimation does not have to be a single pulse signal, but can be a pulse series signal of a specific length, as in Fig. Figure 11 is shown. An embodiment according to the above idea is described below as modification 5.

[0094] The host device in this modification sends the pulse series signal (hereinafter referred to as the response request signal Sa), which represents a specific bit sequence that the mobile device 2The host device requests the response signal to be sent. The host device measures, as the cycle time Tp, for example, the duration from when the host device sends the first pulse of the response request signal Sa until when the host device receives the end of the response signal Sb from the mobile device. 2 receives. If the mobile device 2 Upon receiving the response request signal Sa from the host device, the mobile device sends 2 The pulse series signal, representing a specific sequence of bits, is called the response signal Sb. The length Tγ (in other words, the number of bits) of the response signal Sb is preferably set equal to the length Tβ of the response request signal Sa to simplify the computational processing described below. As an example, setting Ty = Tβ is assumed.

[0095] According to this specification, the time required for the radio signal transmitted through the front-end communication device to travel can be 12X is sent to the mobile device 2 spreads (that is, the initial spreading period) T12 ), can be determined by the following expression 3. The lengths Tβ and Tγ of the usable signals can be the assumed values ​​stored in the flash memory. 112 are stored. T12 = ( Tp − T α − T β − T γ ) / 2 = ( TP − T α − 2 ⋅ T β ) / 2

[0096] T2A, which denotes the distance from the host device to the intercepting device, can be determined by the following expression 4. T 2 A = Tq + T 1 B − T γ − ( T 12 + T β + T α ) = Tq + T 1 A + T β − T 12 − T β − T α = Tq + T 1 A + T 12 − T α

[0097] In the preceding expression 4, the vehicle device-to-vehicle device propagation time T1A can be a value stored in the flash memory. 112is registered, or a measured value determined by the procedure described in Modification 3. The first propagation time T12 can be determined by the preceding expression 3. The response processing time Tα at the mobile device 2 can be a value stored in the flash memory 112 is registered, or the actual measured value recorded by the mobile device 2 will be communicated as described above in Modification 1.

[0098] The position estimation unit F3 can determine the second propagation time T2A, which serves as an indicator of the distance from the mobile device 2 to serve as an intercepting device, by calculating the preceding expression 4 Therefore, the distance from the mobile device can be 2The intercepting device is calculated in the same way. That is to say, the present modification has the same effect as the embodiment mentioned above.

[0099] The response request signal Sa preferably includes a code indicating that the target is the mobile device. 2 The response signal Sb preferably includes a code indicating that the target is the host device and / or includes the response processing time Tα. The response signal Sb can be configured as a signal containing a response code used in the authentication processing of the challenge-response procedure. <Modifikation 6>

[0100] In the embodiment described above, each vehicle-mounted communication device reports 12 the position estimating device 11The length of time between a predetermined event occurring and another predetermined event occurring, such as the orbital period Tp and the pulse reception interval Tq, although this is not a limitation. As in Fig. As shown in 12, any vehicle-mounted communication device can 12 be configured to sequentially use the position estimator 11 The time to report is when it sends the pulse signal, and the time it receives the pulse signal. The event here refers to either the sending of the pulse signal or the receiving of the pulse signal.

[0101] The vehicle-mounted system 1 The present modification is configured such that each vehicle-mounted communication device 12 sequentially the occurrence of the predetermined events of the position estimating device 11 reports, so that the position estimating device 11recognizes the timing of performances at the different events and the position of the mobile device 2 estimates. The reporting (in other words, notification) of the occurrence of various events from each vehicle-mounted communication device. 12 for the position estimation device 11 can be performed by outputting an electrical pulse signal.

[0102] For example, when the host device sends the pulse signal to the position estimating device 11 When the host device sends the electrical pulse signal to the position estimating device, it sends the electrical pulse signal to the position estimating device. 11 and when the host device receives the pulse signal from the mobile device 2 Upon receiving the electrical pulse signal, the host device sends it to the position estimating device. 11, wherein the host device sequentially reports the pulse signal transmission time and the pulse signal reception time. Accordingly, the position estimation device determines 11 a first clock time Tm1, which indicates when the host device sent the pulse signal, and a second clock time Tm2, ​​which indicates when the host device received the pulse signal from the mobile device. 2 has received. Each time the interceptor receives the pulse signal, the interceptor transmits the corresponding electrical pulse signal to the position estimator. 11 from. Consequently, the position estimation device determines 11 a third clock time Tm3, which indicates when the interceptor has received the pulse signal sent by the host device, and a fourth clock time Tm4, which indicates when the interceptor has received the pulse signal sent by the mobile device 2is sent. With such a configuration, the position estimation device can 11 It also calculates the orbital period Tp and the pulse reception interval Tq and thus has the same effect as in the embodiment described above.

[0103] In this respect, communication between the vehicle-mounted communication device 12 and the position estimating device 11 affected by delays originating from the length of the electrical wiring from the vehicle-mounted communication device 12 for the position estimation device 11, the rise time of the pulse signal for communication, and the like. Therefore, it is more likely that the method disclosed in this modification contains errors compared to the embodiment described above. In other words, the configuration of the embodiment described above is not determined by the length of the electrical wiring from the vehicle-mounted communication device. 12 for the position estimation device 11 regarding the calculation of the distance from the intercepting device to the mobile device 2 affected, thereby affecting the mobile device 2 can be estimated more accurately than the configuration disclosed in the present modification.

[0104] The position estimating device 11The present modification can be configured to calculate the vehicle device-to-vehicle device propagation time T1A using a delay time that is specified in advance by testing and that originates from the length of the electrical wiring from the vehicle-mounted communication device. 12 for the position estimation device 11 and includes pulse signal generation processing and / or pulse signal acquisition processing. According to this configuration, the deterioration of the mobile device's position estimation accuracy can occur. 2 compared to the embodiment, reduced. <Modifikation 7>

[0105] In modification 6, the host device and each interceptor notify the position estimator. 11 about the timing for sending / receiving the pulse signal 11 by outputting an electrical pulse signal to the position estimating device11 However, this is not a limitation. If any vehicle-mounted communication device 12 Any vehicle-mounted communication device that has a timing function can 12 Data indicating the cycle time of the event's occurrence is sent to the position estimator. 11 output when it detects the occurrence of the predetermined event.

[0106] For example, the host device can be configured to sequentially provide data specifying the clock time of transmitting and / or receiving the pulse signal, with the clock times determined based on the clock information held by the host device. Furthermore, the host device can be configured to sequentially provide data specifying the clock time of receiving the pulse signal, with the clock time determined based on the clock information held by the interceptor device. The transmit and receive clock times can be expressed, for example, in Coordinated Universal Time (UTC). The clock time of the occurrence of each event can be expressed in a time system based on the frequency of the cesium atom (so-called atomic time). <Modifikation 8>

[0107] In modification 7, the position estimation device 11The transmission timing of the pulse signal is determined by the host device. Furthermore, since the vehicle device-to-vehicle device propagation time T1A from the host device to each interceptor is determined according to the distance between the host device and that interceptor, the time TA is inherently a constant value and the value stored in the flash memory. 112 Once registered, it can be used. Therefore, the position estimation device can be used. 11 Determine the third clock time Tm3, at which a respective interceptor receives the pulse signal sent by the host device, by adding the vehicle-device-to-vehicle-device propagation time T1A to the first clock time Tm1 at an interceptor from the basis of the interceptor, where the first clock time Tm1 corresponds to the timing or the time at which the host device sends the pulse signal.

[0108] Accordingly, it is possible to configure the intercepting device of modification 7 for reporting to the position estimating device from the operation / configuration. 11 the time when the pulse signal sent by the host device is received. In other words, the interceptor can be configured to report only the fourth clock time, Tm4. This configuration corresponds to a configuration that includes a partial reporting or partial reporting operating mode for the interceptor, in which data relating to the clock time of reception of the pulse signal sent by the host device is omitted. 2 is sent (that is, the fourth clock cycle) of the position estimating device 11 are provided, with data that includes the clock time of the reception of the pulse signal sent by the host device (that is, the third clock time), the position estimating device 11not be provided. The case in which the partial message operation mode is applied is preferred over a case in which, for example, the clock information is transmitted between the position estimator. 11 and the intercepting device is synchronized, or in which a clock information deviation amount is known. The idea disclosed in modification 8 is equally applicable to modification 6.

[0109] It is conceivable that the clock information for each of the vehicle-mounted communication devices may not be completely identical (in other words, there may be a discrepancy). Therefore, the vehicle-mounted communication devices 12 The present modification preferably operates in a synchronized state using signals provided by the position estimating device. 11or be entered from an external source. For example, it is preferred that the position estimating device 11 the present modification to any vehicle-mounted communication device 12 outputs a signal to resolve the misalignment of clock information between the devices (in other words, to synchronize).

[0110] In another aspect, the position estimating device can 11 The present modification is configured to determine a clock information deviation amount between the host device and the interceptor, and to calculate the cycle time Tp of the pulse reception interval Tq after correcting the clock time information reported by the interceptor, using the deviation amount. For example, the position estimator calculates 11An expected clock time at which the interceptor receives the pulse signal transmitted by the host device is calculated by adding the vehicle-to-vehicle propagation time T1A to the transmit clock time of the pulse signal sent by the host device. The difference between the expected time and the actual receive clock time reported by the interceptor is then used as the clock information deviation amount between the host device and the interceptor.

[0111] According to the embodiment described above, the orbital period Tp or the pulse reception interval Tq, which is used to estimate the position of the mobile device, 2 can be used within a single vehicle-mounted communication device 12 measured and therefore the vehicle-mounted communication devices must 12They are not synchronized with each other. This means that the configuration of the embodiment described above has the advantage that no synchronization between the vehicle-mounted communication devices is necessary. 12 necessary, and the advantages of having fewer estimation errors resulting from synchronization errors. Every vehicle-mounted communication device 12 The embodiment described above only needs to be equipped with a function for measuring the time between the occurrence of a specific event and the occurrence of a specific event (a so-called timer) and does not need to be equipped with a function for maintaining clock information (i.e., a clock function). Accordingly, the configuration disclosed in the embodiment has the advantage that the configuration of the vehicle-mounted communication device 12compared to the configuration that was in the modifications 7 and 8 It is revealed, it is simplified. (Modification 9)

[0112] In the embodiment described above, the position of the mobile device 2 estimated by the fact that the host device sends the pulse signal and the mobile device 2 the response signal to the pulse signal, although this does not constitute a limitation. As in Fig. As shown in 13, the position of the mobile device can be determined. 2 can be estimated by the fact that the mobile device 2 the pulse signal is sent and the host device interprets the pulse signal as the response to the pulse signal from the mobile device. 2 sends. This configuration is subsequently described as modification 9.

[0113] The mobile device 2In this modification, the time from sending the pulse signal to the host device until receiving the pulse signal from the host device is measured as the orbital period Tp. A pulse series signal indicating the measured orbital period Tp (hereinafter referred to as the time difference message signal Sp) is sent separately.

[0114] When the host device receives the pulse signal from the mobile device 2 The host device receives the pulse signal and, in response to it, sends the pulse signal to the mobile device. 2 That is to say, the host device in this modification corresponds to the vehicle-mounted communication device. 12 , which send a predetermined response signal in response to the response request signal from the mobile device 2 is sent, sends. When the host device receives the time difference message signal Sp from the mobile device. 2Upon receiving, the host device shares the position estimator's information. 11 the data specified in the signal (especially the orbital period Tp).

[0115] In the present modification, the reception of the pulse signal by the intercepting device detaches from the mobile device. 2 It also appears that the interceptor starts measuring the pulse reception interval Tq. That is, the interceptor measures the pulse reception interval Tq as the duration of when the interceptor receives the pulse signal from the mobile device. 2 receives until the interceptor receives the pulse signal from the host device and reports it to the position estimator. 11 .

[0116] In this configuration, the propagation time T21 (=T12) of the signal from the mobile device 2 The host device is determined by the following expressions. In this respect, Tδ represents the... Fig. Figure 13 shows the response processing time at the host device, which is a parameter whose specific value has been determined through testing and / or other means. In other words, the applied response processing time Tδ can be the value stored in the flash memory. 112 is registered. The position estimation unit F3 The present modification leads to the processing according to step S105 Calculating the initial spread time T12 by inserting the orbital period Tp, which is specified in the time difference message signal Sp, into the following expression 5. T12 = ( Tp − T δ ) / 2

[0117] Here, the usable vehicle device-to-vehicle device propagation time T1A can be the value stored in the flash memory. 112is registered, or the measured value determined by the procedure described above as the modification. T21 can be used with the above expression 5 Tq is the parameter observed by the intercepting device. Tδ is the response processing time at the host device, as described above, and the value stored in the flash memory. 112 Once registered, it can be applied. Accordingly, the position of the mobile device can be determined. 2 can also be estimated using the above method. The position estimation unit F3 This modification allows the arithmetic processing of the expression to be processed as a step corresponding to the step. S107 carry out.

[0118] According to the above configuration, there is no need for the mobile device 2operates in a constant receive-ready state, so that it can receive signals from the vehicle-mounted system 1 can receive. Therefore, the energy consumption of the mobile device can be... 2 will be reduced. <Modifikation 10>

[0119] The above are modes in which each vehicle-mounted communication device 12 It includes both transmitting and receiving functions, although this is not a limitation. When the vehicle-mounted communication devices 12 , which act as the host and intercept devices, are fixed, the vehicle-mounted communication device must 12 , which acts as the intercepting device, not necessarily the transmitting circuit 32 It may be sufficient for the intercepting device to include the receiving function. This is particularly true if the front-facing communication device... 12Xas the host device and the right-side communication device 12A , the left-sided communication device 12B and the rear communication device 12C When the intercepting devices are used, the right-hand communication device must be used. 12A , the left-sided communication device 12B and the rear communication device 12C not necessarily the transmission circuit 32 include. It may be sufficient that the vehicle-mounted communication device 12 , which is intended to function as the host device, the transmitting circuit 32 contains. <Zusätzliche Anmerkungen>

[0120] Means and / or functions of the position estimator can be implemented by: software stored in a tangible storage device and a computer that executes the software; software only; hardware only; or a combination thereof. Some or all of the functions of the position estimator 11 can be implemented as hardware. A mode in which a particular function is implemented as hardware includes a mode in which the function is implemented using one or more integrated circuits or the like. If some or all of the functions of the position estimating device 11 This can be provided by an electronic circuit, which is hardware; this can be provided by: a digital circuit including several logic circuits; or an analog circuit. The position estimating device 11can be provided by a single computer or a set of computer resources connected by a data communication device. QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] JP 2018151310

[0001] JP 6093647 B

[0005]

Claims

[1] Mobile device position estimation system for estimating a relative position of a mobile device with respect to a vehicle by performing radio communication according to a predetermined communication procedure between a vehicle-mounted system (1) mounted on a vehicle and the mobile device (2) carried by a user of the vehicle, wherein the vehicle-mounted system comprises: a transceiver (12X) which is a communication module configured to send and receive radio signals to and from the mobile device; several interceptor devices (12A, 12B, 12C) configured to receive radio signals transmitted by the mobile device and the transceiver; and a position estimation unit (F3) that estimates the position of the mobile device based on the result of communication between the transmitter-receiver and the mobile device and the states of reception of the radio signals by the multiple respective interceptors, wherein the transceiver is configured to send a predetermined response request signal as the radio signal to the mobile device, wherein the mobile device is configured to send a response signal as a response when the mobile device receives the response request signal from the transceiver, and The position estimation unit includes: a first propagation time determination unit (S105) that determines a first propagation time, which is a propagation time of the radio signal from the transceiver to the mobile device, based on a round-trip time, which is a duration from when the transceiver sends the reply request signal until when the transceiver receives the reply signal from the mobile device; a second propagation time determination unit (S107) that determines for each of the multiple interceptors a second propagation time, which is a propagation time of the radio signal from the mobile device to the interceptor, based on a signal reception interval that is a duration from when the interceptor receives the response request signal until when the interceptor receives the response signal, and the orbital period; and a position estimation processing unit (S108) that estimates the position of the mobile device based on the first propagation time determined by the first propagation time determination unit and the second propagation times determined by the second propagation time determination unit. [2] Mobile device position estimation system according to claim 1, comprising: a parameter storage unit (112) that stores: an assumed value of a vehicle device-to-vehicle device transmission time required for the radio signal sent by the transceiver to be received by the interceptor; and an assumed value of a response processing time required from when the mobile device receives the response request signal until when the mobile device sends the response signal. wherein the mobile device position estimation system is configured such that: The first propagation time determination unit calculates the first propagation time by dividing a value by 2, which is obtained by subtracting the assumed value of the response processing time from the round-trip time; and The second propagation time determination unit calculates the second propagation time by: the signal reception interval plus the assumed value of the vehicle device-to-vehicle device propagation time minus the first propagation time minus the assumed value of the response processing time. [3] Mobile device position estimation system according to claim 2, wherein the mobile device is configured to: measure the response processing time required from when the mobile device receives the response request signal until when the mobile device sends the response signal as a response; and send a radio signal indicating the measured response processing time as a processing time notification signal. the position estimating unit includes a response processing time retention unit (113) which retains the response processing time specified in the processing time message signal as an actual processing time when the position estimating unit receives the processing time message signal sent by the mobile device, the mobile device position estimation system is configured such that: the first propagation time determination unit determines the first propagation time using the actual processing time instead of the assumed value of the response processing time that is pre-registered, when the actual processing time is retained by the response processing time retention unit; and The second propagation time determination unit determines the second propagation time using the actual processing time instead of the assumed value of the response processing time that is pre-registered, if the actual processing time is retained by the response processing time retention unit. [4] Mobile device position estimation system according to any one of claims 1 to 3, wherein several of the transmitters and receivers are included, The mobile device position estimation system includes a role designation unit (F2) that: designates one of the multiple transceivers as a host device responsible for sending the response request signal to the mobile device; and causes the transceivers, except for the host device, to function as the interceptors, and In a predetermined cycle, the role assignment unit changes the send-receiver, which acts as the host device. [5] Mobile device position estimation system according to any one of claims 1 to 4, wherein the transceiver is configured to perform measurements of the orbital period and to provide data indicating a result of the measurement to the position estimating unit, the multiple intercept devices are each configured to perform measurements of the signal reception interval and to provide data indicating a result of the measurement to the position estimation unit, and the mobile device position estimation system is configured such that: the first propagation time determination unit determines the first propagation time based on the orbital period provided by the transmit-receiver; and The second propagation time determination unit determines the second propagation time for each interceptor based on the signal reception interval provided by each interceptor and the first propagation time. [6] Mobile device position estimation system according to any one of claims 1 to 4, wherein the transceiver is configured to sequentially provide the position estimating unit with data specifying a clock time for sending the response request signal and data specifying a clock time for receiving the response signal from the mobile device. the multiple intercept devices are each configured to sequentially provide the position estimation unit with data specifying a clock time of receiving the response request signal, and data specifying a clock time of receiving the response signal. the first propagation time determination unit is configured to determine the orbital period based on the data provided by the transceiver, and to determine the first propagation time based on the orbital period, and the second propagation time determination unit is configured to determine the signal reception interval for each interceptor based on the data provided by the interceptor, and to determine the second propagation time for each interceptor based on the signal reception interval for each interceptor and the first propagation time. [7] Mobile device position estimation system according to claim 6, wherein the intercepting device includes an operating mode in which the data indicating the clock time of receiving the response signal are provided to the position estimation unit, while the data indicating the time of receiving the response request signal are not provided to the position estimation unit. [8] Mobile device position estimation system for estimating a relative position of a mobile device with respect to a vehicle by performing radio communication according to a predetermined communication procedure between a vehicle-mounted system (1) mounted on a vehicle and the mobile device (2) carried by a user of the vehicle, wherein The mobile device is configured to: send a response request signal, which is a radio signal that requests the vehicle-mounted system to send a response signal as a reply; and to: when the mobile device receives the response signal, send a time difference message signal to the vehicle-mounted system, which is a radio signal that specifies a round-trip time, which is the duration from receiving the response request signal to receiving the response signal. the vehicle-mounted system features: a transceiver (12X) which is a communication module configured to send and receive radio signals to and from the mobile device using a predetermined communication method; several interceptor devices (12A, 12B, 12C) configured to receive radio signals transmitted by the mobile device and the transceiver; and a position estimation unit (F3) that estimates the position of the mobile device based on the result of communication between the transmitter / receiver and the mobile device, and the states of reception of the radio signals by respective interceptors, wherein the transceiver is configured to send the response signal as a response when the transceiver receives the response request signal from the mobile device, and The position estimation unit includes: a first propagation time determination unit (S105) that determines a first propagation time, which is a propagation time of the radio signal from the transceiver to the mobile device, based on the round-trip time specified in the time difference message signal, a second propagation time determination unit (S107) that determines for each of the multiple interceptors a second propagation time, which is a propagation time of the radio signal from the mobile device to a respective interceptor, based on a signal reception interval that is a duration from when the respective interceptor receives the response request signal until when the respective interceptor receives the response signal, and the orbital period; and a position estimation processing unit (S108) that estimates the position of the mobile device based on the first propagation time determined by the first propagation time determination unit and the second propagation times determined by the second propagation time determination unit.