WO2016114169A1

WO2016114169A1 - Receiving apparatus, communication apparatus, calculation method, and computer program

Info

Publication number: WO2016114169A1
Application number: PCT/JP2016/050096
Authority: WO
Inventors: 大輔宮脇
Original assignee: 株式会社オートネットワーク技術研究所; 住友電装株式会社; 住友電気工業株式会社
Priority date: 2015-01-14
Filing date: 2016-01-05
Publication date: 2016-07-21
Also published as: JP2016131327A

Abstract

Provided is a receiving apparatus capable of reducing the number of components needed when acquiring digital data representing the waveform of each signal when received analog signals are separated into two signals having mutually orthogonal phases and capable of reducing the processing load when acquiring said digital data. The receiving apparatus converts received analog signals into first digital data at a first A/D conversion unit and converts periodic signals corresponding to the analog signals into second digital data at a second A/D conversion unit. The receiving apparatus, with a selection unit, selects the second digital data converted at time points corresponding to when an integral multiple of 1/4 the period of the periodic signals has elapsed from a predetermined time point and the first digital data converted synchronously with each of the second digital data. The receiving apparatus, on the basis of the selected data, calculates digital data representing the waveform of each signal when the analog signals are separated into two signals having mutually orthogonal phases at a first calculation unit and a second calculation unit.

Description

Reception device, communication system, calculation method, and computer program

The present application relates to a receiving device that calculates digital data representing the waveform of each signal when the received analog signal is separated into two signals that are orthogonal to each other, and a communication system including the receiving device. The present invention also relates to a calculation method and computer program for calculating digital data representing the waveform of each signal when an arbitrary analog signal is separated into two signals whose phases are orthogonal to each other.

Conventionally, a receiving apparatus that receives an analog signal from the outside and separates the received analog signal into two signals whose phases are orthogonal to each other is known. The receiving apparatus converts each separated signal into digital data, and performs various processes such as demodulation of the analog signal by using the converted digital data. In general, a receiving apparatus includes a quadrature detector and an A / D converter, thereby acquiring the digital data. Specifically, the receiving apparatus separates an analog signal received using a quadrature detector into two signals that are orthogonal to each other. Thereafter, the receiving apparatus converts each separated signal into digital data using an A / D converter.

On the other hand, the receiving device (array antenna device) described in Patent Document 1 converts a received analog signal into digital data in advance by an A / D converter. Thereafter, the receiving device multiplies the converted digital data by a sine wave signal and a cosine wave signal, thereby separating the analog signal into two signals whose phases are orthogonal to each other, and represents digital data representing the waveform of each signal. Is calculated.

Japanese Patent No. 5190536

In recent years, a receiving apparatus including a plurality of receiving antennas is known in order to increase the receiving sensitivity of a desired analog signal. Such a receiving apparatus needs to perform various processes on each analog signal received by each receiving antenna. As described above, in the case of a receiving device that acquires desired digital data using a quadrature detector and an A / D converter, as many quadrature detectors as the number of reception antennas are necessary, and the components of the analog circuit that constitutes the quadrature detector Score increases. Therefore, there is a problem that the cost for configuring the receiver increases. Moreover, in the receiving apparatus described in Patent Document 1, a sine wave signal or a cosine wave signal is multiplied with all digital data converted by the A / D converter. Therefore, when there are a plurality of receiving antennas, there is a problem that the processing load of the receiving apparatus increases.

The purpose of the present application is to reduce the number of parts required to acquire digital data representing the waveform of each signal when the received analog signal is separated into two signals whose phases are orthogonal to each other, and to reduce the processing load upon acquisition. It is an object to provide a receiving apparatus, a communication system, a calculation method, and a computer program that can be reduced.

A receiving device according to one embodiment of the present invention receives an analog signal, and based on the received analog signal and an analog periodic signal corresponding to the analog signal, the analog signal is a first signal and a first signal whose phases are orthogonal to each other. A receiving device for calculating digital data representing a waveform of each signal when separated into two signals, a first A / D converter for converting a received analog signal into first digital data, and the first A / D conversion A second A / D converter that converts the periodic signal into second digital data in synchronization with the first digital data, and among the second digital data converted by the second A / D converter, 1 of the periodic signal from a predetermined time point / 4 second digital data converted at each timing corresponding to the time when an integral multiple of four cycles has passed, and the first digital data converted in synchronization with each of the second digital data, The waveform of the first signal is expressed by multiplying the selection unit to be selected, and the value of the first digital data and the value of the second digital data that are selected by the selection unit and converted at an arbitrary timing synchronized with each other. A first calculation unit that calculates digital data, a value of the first digital data converted at the arbitrary timing, and a second digital that is selected by the selection unit and converted at one timing continuous to the arbitrary timing The waveform of the second signal is obtained by multiplying the value of the data, or by multiplying the value of the second digital data converted at the arbitrary timing and the value of the first digital data converted at the one timing. And a second calculation unit that calculates digital data representing.

A communication system according to one embodiment of the present invention includes the above-described reception device and a transmission device that transmits an analog signal, and the reception device receives the analog signal transmitted from the transmission device, and receives the received analog signal. Digital data representing the waveform of each signal when the signal is separated into a first signal and a second signal whose phases are orthogonal to each other is calculated.

The calculation method according to one aspect of the present invention is based on separation of an analog signal into a first signal and a second signal whose phases are orthogonal to each other based on an arbitrary analog signal and an analog periodic signal corresponding to the analog signal. A digital data representing a waveform of each signal in the first A / D conversion step for converting the analog signal into first digital data, and in synchronization with the first A / D conversion step, A second A / D conversion step for converting the periodic signal into second digital data, and the second digital data converted in the second A / D conversion step, which is an integral multiple of a quarter period of the periodic signal from a predetermined time point The second digital data converted at each timing corresponding to the point in time that has passed, and the first digital data converted in synchronization with each of the second digital data are selected. A digital signal representing the waveform of the first signal by multiplying the value of the first digital data and the value of the second digital data selected at the selection step and converted at an arbitrary timing synchronized with each other. A first calculation step for calculating data; a value of the first digital data converted at the arbitrary timing; and the second digital data selected by the selection unit and converted at one timing continuous with the arbitrary timing. Or the value of the second digital data converted at the arbitrary timing and the value of the first digital data converted at the one timing to multiply the waveform of the second signal. A second calculation step of calculating digital data to be represented.

The computer program according to one embodiment of the present invention is based on an arbitrary analog signal and an analog periodic signal corresponding to the analog signal, and separates the analog signal into two signals whose phases are orthogonal to each other. A computer program for causing a computer to calculate digital data representing a waveform, wherein the computer is synchronized with a first A / D converter that converts the analog signal into first digital data, and the first A / D converter. A second A / D conversion unit that converts the periodic signal into second digital data, and second digital data converted by the second A / D conversion unit, which is a quarter cycle of the periodic signal from a predetermined time point. The second digital data converted at each timing corresponding to the time point at which the integral multiple has elapsed, and the second digital data are changed in synchronization with the second digital data. A selection unit that selects the first digital data, and by multiplying the value of the first digital data and the value of the second digital data that are selected by the selection unit and converted at any timing synchronized with each other, A first calculation unit that calculates digital data representing a waveform of the first signal, a value of the first digital data converted at the arbitrary timing, and one timing selected by the selection unit and continuing to the arbitrary timing Or by multiplying the value of the second digital data converted at step 1 or the value of the second digital data converted at the arbitrary timing and the value of the first digital data converted at the one timing. And functioning as a second calculation unit for calculating digital data representing the waveform of the second signal.

Note that the present application can be realized not only as a receiving device and a communication system including such a characteristic processing unit, but also as a communication method using such characteristic processing as a step, It can be realized as a program for execution. Further, it can be realized as a semiconductor integrated circuit that realizes part or all of the receiving device and the communication system, or can be realized as another system including the receiving device and the communication system.

According to the above, the number of parts required for acquiring digital data representing the waveform of each signal when the received analog signal is separated into two signals whose phases are orthogonal to each other is reduced, and the processing load for acquisition is reduced. Can be reduced.

1 is a schematic diagram illustrating a configuration example of a communication system according to Embodiment 1. FIG. It is a block diagram which shows the structure of a transmitter. It is a block diagram which shows the structure of a receiver. It is a flowchart which shows the process sequence of the receiver when detecting the penetration | invasion into a vehicle interior. It is explanatory drawing explaining the process sequence of a component calculation process. It is explanatory drawing which shows the specific example of a conversion result table. It is explanatory drawing which shows notionally the conversion result of a 2nd A / D conversion process. It is explanatory drawing which shows the specific example of a selection result table. It is explanatory drawing which shows the specific example of a calculation result table. It is a flowchart which shows the subroutine of a component calculation process. It is a flowchart which shows the subroutine of a selection process. It is a flowchart which shows the subroutine of a 1st calculation process. It is a flowchart which shows the subroutine of a 2nd calculation process. 6 is a block diagram illustrating a configuration of a receiving device according to Embodiment 2. FIG. It is a flowchart which shows the process sequence of the receiver when detecting the penetration | invasion into a vehicle interior. It is a flowchart which shows the subroutine of the selection process in a modification.

[Description of Embodiment of the Present Invention]
First, embodiments of the present invention will be listed and described. Moreover, you may combine arbitrarily at least one part of embodiment described below.

(1) A receiving apparatus according to an aspect of the present invention receives an analog signal, and the first analog signals are in phase with each other based on the received analog signal and an analog periodic signal corresponding to the analog signal. A receiving device for calculating digital data representing a waveform of each signal when separated into a signal and a second signal, a first A / D converter for converting a received analog signal into first digital data, and the first A A second A / D converter that converts the periodic signal into second digital data in synchronization with the / D converter, and the second digital data converted by the second A / D converter from the predetermined time point to the period Second digital data converted at each timing corresponding to a point when an integral multiple of a quarter period of the signal has elapsed, and first digital data converted in synchronization with each of the second digital data By multiplying the value of the first digital data and the value of the second digital data that are selected by the selection unit and converted at an arbitrary timing synchronized with each other. A first calculation unit that calculates digital data to be represented, and a value of the first digital data converted at the arbitrary timing and the second selection unit selected by the selection unit and converted at one timing continuous to the arbitrary timing By multiplying the value of the digital data, or by multiplying the value of the second digital data converted at the arbitrary timing and the value of the first digital data converted at the one timing, A second calculating unit that calculates digital data representing the waveform.

In the present application, the first A / D conversion unit converts the received analog signal into first digital data. The second A / D conversion unit converts an analog periodic signal corresponding to the received analog signal into second digital data in synchronization with the first A / D conversion unit. The selection unit converts the second digital data converted by the second A / D conversion unit at each timing corresponding to a point when an integral multiple of ¼ period of the periodic signal has elapsed from a predetermined point in time. Select data. The selection unit selects the first digital data converted in synchronization with each of the second digital data. The first calculation unit is digital data that represents the waveform of the first signal by multiplying the value of the first digital data and the value of the second digital data that are selected by the selection unit and converted at an arbitrary timing synchronized with each other. Is calculated. The second calculation unit calculates the value of the first digital data converted at the arbitrary timing and the value of the second digital data selected by the selection unit and converted at one timing continuous to the arbitrary timing. By multiplying, digital data representing the waveform of the second signal is calculated. Alternatively, the second calculation unit multiplies the value of the second digital data converted at the arbitrary timing by the value of the first digital data converted at the one timing, whereby the second signal Digital data representing the waveform is calculated.
Therefore, digital data representing the waveform of each signal when the received analog signal is separated into two signals whose phases are orthogonal to each other can be calculated without using a quadrature detector. Therefore, the number of parts required for acquiring the digital data can be reduced. Further, digital data representing the waveform of each signal can be calculated using the first digital data and the second digital data selected by the selection unit. Therefore, it is possible to reduce the processing load when acquiring the digital data. Note that the second calculation unit only needs to be configured to multiply the first digital data and the second digital data whose phases are different from each other corresponding to a quarter period of the periodic signal.

(2) The periodic signal has a sine wave shape having an initial phase corresponding to the analog signal, and the selection unit is a second digital data corresponding to the value of the periodic signal when the phase is 90 degrees or 270 degrees. In addition, it is preferable that at least the first digital data converted in synchronization with the second digital data is selected.

In the present application, the periodic signal has a sine wave shape having an initial phase corresponding to the analog signal. The selection unit selects at least the second digital data corresponding to the value of the periodic signal when the phase is 90 degrees or 270 degrees and the first digital data converted in synchronization with the second digital data. The value of the periodic signal when the phase is 90 degrees or 270 degrees is the maximum value or the minimum value of the periodic signal. Therefore, for example, by selecting the value of the periodic signal when the phase is 90 degrees, 180 degrees, 270 degrees, and 360 degrees, the local maximum point, the local minimum point, and the center point of the periodic signal can be acquired. The selection unit can select the second digital data representing the outline of the periodic signal and the first digital data converted in synchronization with the second digital data by acquiring each point. Therefore, the values of the digital data calculated by the first calculation unit and the second calculation unit can be made closer to the values of the first signal and the second signal, respectively.

(3) Calculate digital data representing a waveform of each signal provided with a plurality of receiving antennas and separating the analog signals received by the plurality of receiving antennas into a first signal and a second signal whose phases are orthogonal to each other. Thus, a certain configuration is preferable.

In the present application, the receiving device includes a plurality of receiving antennas. Further, the receiving device calculates digital data representing the waveform of each signal when the analog signals received by the plurality of receiving antennas are separated into the first signal and the second signal whose phases are orthogonal to each other.

(4) A communication system according to an aspect of the present invention includes the above-described reception device and a transmission device that transmits an analog signal, and the reception device receives and receives an analog signal transmitted from the transmission device. Digital data representing the waveform of each signal when the analog signal is separated into a first signal and a second signal whose phases are orthogonal to each other is calculated.

The present application includes the above-described receiving device and a transmitting device that transmits an analog signal. The receiving device receives the analog signal transmitted from the transmitting device, and calculates digital data representing the waveform of each signal when the received analog signal is separated into a first signal and a second signal whose phases are orthogonal to each other. Therefore, digital data representing the waveform of each signal when the received analog signal is separated into two signals whose phases are orthogonal to each other can be calculated without using a quadrature detector. Therefore, it is possible to reduce the number of parts of the receiving device required when acquiring the digital data. Further, the receiving device can calculate digital data representing the waveform of each signal using the first digital data and the second digital data selected by the selection unit. Therefore, it is possible to reduce the processing load on the receiving apparatus when acquiring the digital data.

(5) The transmission device is configured to transmit an analog signal as needed, and the reception device stores information related to the analog signal received in a specific state around itself, and stores the information in the storage unit. The specific state and the analog signal are transmitted based on the calculated information and the values calculated by the first calculation unit and the second calculation unit when receiving the analog signal transmitted from the transmission device as needed. It is preferable to include a comparison unit that compares the surrounding state of the transmission device and a detection unit that detects an event that occurs within the communication range of the transmission device based on the comparison result of the comparison unit.

In the present application, the transmission device transmits an analog signal as needed. The receiving device stores information on the analog signal received in a specific state around the receiving device in the storage unit. Based on the information stored in the storage unit and the values calculated by the first calculation unit and the second calculation unit described above when receiving the analog signal transmitted from the transmission device as needed And the surrounding state when the analog signal is transmitted are compared by the comparator. Based on the comparison result of the comparison unit, the reception device detects an event that has occurred in the transmission device and its own communication range by the detection unit. Therefore, the receiving apparatus can detect a change in state within the communication range.

(6) The information stored in the storage unit is a feature amount related to the specific state, and the reception device is based on each value calculated by the first calculation unit and the second calculation unit. A feature amount calculation unit that calculates a feature amount related to the surrounding state is further provided, and the comparison unit compares the feature amount calculated by the feature amount calculation unit with the feature amount related to the specific state. A configuration is preferred.

In the present application, the information stored in the storage unit of the receiving device is a feature amount related to a specific state. Based on the values calculated by the first calculation unit and the second calculation unit, the reception device calculates the feature amount related to the surrounding state of the reception device by the feature amount calculation unit. The comparison unit compares the feature amount calculated by the feature amount calculation unit with the feature amount related to the specific state stored in the storage unit.

(7) In the calculation method according to one aspect of the present invention, based on an arbitrary analog signal and an analog periodic signal corresponding to the analog signal, the analog signal is converted into a first signal and a second signal whose phases are orthogonal to each other. A calculation method for calculating digital data representing a waveform of each signal when separated, wherein the analog signal is converted into first digital data, and the first A / D conversion step is synchronized with the first A / D conversion step. A second A / D conversion step for converting the periodic signal into second digital data, and the second digital data converted in the second A / D conversion step from the predetermined time point to a quarter period of the periodic signal. Second digital data converted at each timing corresponding to the time when an integral multiple of the first multiple has passed, and first digital data converted in synchronization with each of the second digital data The waveform of the first signal is represented by multiplying the selection step to be selected, and the value of the first digital data and the value of the second digital data selected at the selection step and converted at any timing synchronized with each other. A first calculation step for calculating digital data; a value of the first digital data converted at the arbitrary timing; and a second digital signal selected by the selection unit and converted at one timing continuous with the arbitrary timing The waveform of the second signal is obtained by multiplying the value of the data, or by multiplying the value of the second digital data converted at the arbitrary timing and the value of the first digital data converted at the one timing. A second calculation step of calculating digital data representing

In the present application, the first A / D conversion step converts an analog signal into first digital data. In the second A / D conversion step, the periodic signal corresponding to the analog signal is converted into second digital data. In the selection step, the second digital data converted at each timing to be loaded when an integral multiple of ¼ period of the periodic signal has elapsed from a predetermined time point in the second digital data converted in the second A / D conversion step. Select data. In the selection step, the first digital data converted in synchronization with the second digital data is selected. In the first calculation step, digital data representing the waveform of the first signal is obtained by multiplying the value of the first digital data and the value of the second digital data selected at the selection step and converted at an arbitrary timing synchronized with each other. Is calculated. In the second calculation step, the value of the first digital data converted at the arbitrary timing and the value of the second digital data selected by the selection unit and converted at one timing continuous to the arbitrary timing are calculated. By multiplying, digital data representing the waveform of the second signal is calculated. Alternatively, the second calculation step multiplies the value of the second digital data converted at the arbitrary timing by the value of the first digital data converted at the one timing, so that the second signal Digital data representing the waveform is calculated.
Therefore, digital data representing the waveform of each signal when the received analog signal is separated into two signals whose phases are orthogonal to each other can be calculated without using a quadrature detector. Therefore, by using the calculation method of the present application, it is possible to reduce the number of components having a configuration required when acquiring the digital data. Further, digital data representing the waveform of each signal can be calculated using the first digital data and the second digital data selected in the selection step. Therefore, the processing load of the configuration using the calculation method of the present application when acquiring the digital data can be reduced. The second calculation step may be a procedure that multiplies the first digital data and the second digital data that are different in phase from each other by an amount corresponding to a quarter period of the periodic signal.

(8) The computer program according to one aspect of the present invention is based on the fact that the analog signal is separated into two signals whose phases are orthogonal to each other based on an arbitrary analog signal and an analog periodic signal corresponding to the analog signal. A computer program for causing a computer to calculate digital data representing the waveform of each signal, wherein the computer converts the analog signal into first digital data, and the first A / D converter. In synchronization with the second digital data, a second A / D converter that converts the periodic signal into second digital data, and the second digital data converted by the second A / D converter 1 / of the periodic signal from a predetermined time point. The second digital data converted at each timing corresponding to the time point at which an integral multiple of four cycles has passed, and the second digital data are synchronized with each other. A selection unit that selects the converted first digital data, and a value of the first digital data and a value of the second digital data that are selected by the selection unit and converted at any timing synchronized with each other, A first calculation unit that calculates digital data representing a waveform of the first signal, a value of the first digital data converted at the arbitrary timing, and the selection unit, and one selected continuously from the arbitrary timing Multiply the value of the second digital data converted at the timing, or multiply the value of the second digital data converted at the arbitrary timing and the value of the first digital data converted at the one timing. Thus, it functions as a second calculator that calculates digital data representing the waveform of the second signal.

In the present application, the computer converts an analog signal into first digital data, and converts a periodic signal corresponding to the analog signal into second digital data. The computer selects, from the converted second digital data, the second digital data converted at each timing corresponding to the time when an integral multiple of ¼ period of the periodic signal has elapsed from a predetermined time. Further, the computer selects the first digital data converted in synchronization with the second digital data. The computer multiplies the value of the first digital data and the value of the second digital data, which are converted at an arbitrary timing synchronized with each other, among the selected first digital data and second digital data, thereby obtaining the first signal. The digital data representing the waveform is calculated. The computer includes a value of the first digital data converted at the arbitrary timing, and a value of the second digital data converted at one timing continuous to the arbitrary timing among the selected second digital data. Is multiplied to calculate digital data representing the waveform of the second signal. Alternatively, the second calculation unit multiplies the value of the second digital data converted at the arbitrary timing by the value of the first digital data converted at the one timing, whereby the second signal Digital data representing the waveform is calculated.
Therefore, digital data representing the waveform of each signal when the received analog signal is separated into two signals whose phases are orthogonal to each other can be calculated without using a quadrature detector. Therefore, the number of parts required for acquiring the digital data can be reduced. In addition, digital data representing the waveform of each signal can be calculated using the first digital data and the second digital data selected by causing the computer to function as a selection unit. Therefore, it is possible to reduce the processing load on the computer when acquiring the digital data. When the computer functions as the second calculation unit, it is only necessary to multiply the first digital data and the second digital data whose phases are different from each other corresponding to a quarter period of the periodic signal.

[Details of the embodiment of the present invention]
A specific example of a communication system according to an embodiment of the present invention will be described below with reference to the drawings. In addition, this invention is not limited to these illustrations, is shown by the claim, and it is intended that all the changes within the meaning and range equivalent to the claim are included.

(Embodiment 1)
FIG. 1 is a schematic diagram illustrating a configuration example of a communication system according to the first embodiment. The communication system according to the first embodiment includes a receiving device 1 and a transmitting device 2 that are provided in a passenger compartment of the vehicle C. The transmission device 2 includes a transmission antenna 2a and transmits an analog radio signal from the transmission antenna 2a. The receiving apparatus 1 includes a plurality of receiving antennas 1a, and receives an analog radio signal transmitted from the transmitting apparatus 2 via each receiving antenna 1a. The radio signal received by the receiving apparatus 1 includes, for example, a radio signal directly propagated from the transmission antenna 2a to the reception antenna 1a, a radio signal reflected and propagated at various locations such as an inner wall, a seat, and a floor surface in the vehicle interior and a vehicle Radio signals reflected and propagated at various places such as outdoor persons and obstacles are included. The receiving device 1 and the transmitting device 2 are connected via a communication line 3 and output an analog reference signal described later from the transmitting device 2 to the receiving device 1. The receiving device 1 detects an event occurring in the communication range of the transmitting device 2 and itself based on the analog radio signal and the reference signal transmitted from the transmitting device. The receiving device 1 according to the first embodiment detects, for example, the presence or absence of an intruder into the passenger compartment of the vehicle C and the presence or absence of a person approaching the vehicle C as events. In the following description, unless otherwise specified, the radio signal transmitted by the transmission device 2 and the reference signal output are analog signals. In the following, the configuration and processing when the receiving device 1 detects the presence or absence of an intruder into the vehicle interior of the vehicle C will be mainly described.

FIG. 2 is a block diagram illustrating a configuration of the transmission device 2. The transmission device 2 includes a control unit 21, a storage unit 22, a temporary storage unit 23, a transmission unit 24, and an output unit 25, and each unit is connected via a bus. The control unit 21 includes, for example, one or more CPUs (Central Processing Unit), a multi-core CPU, and the like. The control unit 21 reads a later-described control program stored in the storage unit 22 and controls each unit.

The storage unit 22 includes a nonvolatile memory such as an EEPROM (Electrically-Erasable-and Programmable-ROM), a flash memory, and an HDD (Hard Disk-Drive). The storage unit 22 stores a control program. The control program is a computer program in which the processing content when the control unit 21 transmits a wireless signal, the processing content when the reference signal is output, and the processing content when each unit is controlled is described.

The temporary storage unit 23 is configured by a memory such as SRAM (Static RAM) or DRAM (Dynamic RAM). The temporary storage unit 23 temporarily stores various data generated by the control unit 21 performing processing based on the control program.

The transmission unit 24 is connected to the transmission antenna 2a, and transmits a radio signal having a predetermined frequency from the transmission antenna 2a according to the control of the control unit 21. The predetermined frequency is, for example, a frequency within various frequency bands such as an LF (LowencyFrequency) band and an UHF (Ultra High Frequency) band, and is not particularly limited. The radio signal need not be modulated, but may be modulated by various modulation schemes.

The receiving device 1 is connected to the output unit 25 via the communication line 3. For example, the control unit 21 causes the oscillation circuit to generate a reference signal corresponding to a radio signal to be transmitted to the transmission unit 24, and outputs the reference signal from the output unit 25 to the reception device 1. The reference signal is a periodic signal. For example, when the radio signal is not modulated, the reference signal is the same analog signal as the radio signal. When the modulation is performed, the reference signal is a carrier wave before modulation. In the first embodiment, the reference signal is an analog signal indicating a sine wave waveform.

FIG. 3 is a block diagram showing the configuration of the receiving device 1. The receiving device 1 includes a control unit 11, a storage unit 12, a temporary storage unit 13, a receiving unit 14, a reading unit 15, and a second A / D conversion unit 16, and each unit is connected via a bus. The control unit 11 includes, for example, one or a plurality of CPUs, a multi-core CPU, and the like. The control unit 11 reads a control program described later stored in the storage unit 12 and controls each unit.

The storage unit 12 includes a nonvolatile memory such as an EEPROM, a flash memory, or an HDD. The storage unit 12 stores reference information 12a. The reference information 12a is information related to a radio signal received by the receiving device 1 when the surroundings of the receiving device 1 are in a specific state. The reference information 12a is, for example, information related to the arrival angle of the radio signal and information related to the delay profile when the radio signal transmitted from the transmission device 2 is received by each of the receiving antennas 1a in a state where there is no person in the cabin of the vehicle C. This is information related to radio wave propagation characteristics such as. The control unit 11 refers to the reference information 12a when detecting whether or not the vehicle C has entered the passenger compartment. The storage unit 12 stores a control program. The control program is a computer program in which processing details when a wireless signal is received from the transmission device 2, processing details when a reference signal is input, and processing details for controlling each unit are described.

The temporary storage unit 13 is configured by a memory such as SRAM or DRAM. The temporary storage unit 13 temporarily stores various data generated by the control unit 11 performing processing based on the control program.

The reception unit 14 includes the same number of first A / D conversion units 14a as the number of reception antennas 1a. The first A / D converter 14a includes, for example, an A / D converter, and is connected to one receiving antenna 1a. The first A / D converter 14a converts an analog signal received from the connected receiving antenna 1a into digital data. In accordance with an instruction from the control unit 11, the reception unit 14 causes the first A / D conversion unit 14 a to convert the received analog signal into digital data, and outputs the converted digital data to the control unit 11. Hereinafter, the digital data converted by the first A / D conversion unit 14a is referred to as first digital data.

The reading unit 15 is configured to be able to read information from the recording medium 4 such as a CD-ROM, DVD, Blu-ray disc, or flexible disk. The control unit 11 stores the data recorded on the recording medium 4 read by the reading unit 15 in the temporary storage unit 13 or the storage unit 12. In the recording medium 4, a control program 4 a for operating the receiving device 1 by being executed by the control unit 11 is recorded. The control program stored in the storage unit 12 may be a copy of the control program 4 a read by the reading unit 15 from the recording medium 4. The recording medium 4 may store other information to be stored in the storage unit 12 such as the reference information 12 a and the control unit 11 may store the information in the storage unit 12.

The second A / D conversion unit 16 includes, for example, an A / D converter, converts an input analog signal into digital data, and outputs the converted digital data to the control unit 11. The second A / D conversion unit 16 is connected to the input / output unit 17. The input / output unit 17 is connected to the transmission device 2 via the communication line 3. The input / output unit 17 is an interface that inputs the reference signal output from the transmission device 2 and outputs the input reference signal to the second A / D conversion unit 16. is there. The second A / D conversion unit 16 converts the reference signal output from the input / output unit 17 into digital data in accordance with an instruction from the control unit 11. Hereinafter, the digital data converted by the second A / D converter 16 is referred to as second digital data.

In the communication system configured as described above, the transmission device 2 repeatedly transmits a radio signal at a predetermined time interval such as 1 second. In addition, the transmission device 2 outputs a reference signal to the reception device 1 every time a radio signal is transmitted. Each time the reception antenna 1a receives the radio signal from the transmission device 2, the reception device 1 separates the reception signal corresponding to each reception antenna 1a into two signals whose phases are orthogonal to each other. Calculate digital data to represent. The receiving device 1 detects the presence or absence of an intruder using each calculated digital data and the reference information 12a stored in the storage unit 12. Hereinafter, of the two signals, digital data representing the waveform of the signal corresponding to the first signal of the present application is referred to as an in-phase component, and digital data representing the waveform corresponding to the second signal of the present application is referred to as a quadrature component. In addition, although the transmission apparatus 2 demonstrated the example which transmits a radio signal repeatedly, you may transmit a radio signal continuously.

FIG. 4 is a flowchart showing a processing procedure of the receiving apparatus 1 when detecting entry into the vehicle interior. The control unit 11 of the reception device 1 determines whether or not the reception unit 14 has received a radio signal transmitted from the transmission device 2 (step S11). When it determines with not receiving the radio signal (S11: NO), the control part 11 waits until it receives a radio signal.

When it is determined that a wireless signal has been received (S11: YES), the control unit 11 determines whether or not a reference signal from the transmission device 2 has been input to the input / output unit 17 (step S12). When it determines with the reference signal not being input (S12: NO), the control part 11 waits until a reference signal is input. Note that the processing in step S11 and step S12 may be performed in parallel, or the processing order may be reversed. In addition, when one of the reception of the radio signal and the input of the reference signal is not performed until a predetermined time such as 1 second elapses, the control unit 11 finishes the process. May be.

When it is determined that the reference signal has been input (S12: YES), the control unit 11 performs a component calculation process (step S13). The component calculation process is a process of calculating an in-phase component and a quadrature component in each radio signal received by each receiving antenna 1a. The component calculation process is executed using the received radio signal and the input reference signal, details of which will be described later.

Next, the control unit 11 calculates the feature amount using the in-phase component and the quadrature component calculated from the radio signal received by each receiving antenna 1a (step S14). The feature amount is a feature amount related to the surrounding state of the reception device 1 when the wireless signal from the transmission device 2 is received in step S11. For example, the control unit 11 calculates information related to the arrival angle of the received radio signal using the calculated in-phase component and quadrature component. The control unit 11 functions as a feature amount calculation unit by executing a control program in step S14.

Next, the control unit 11 compares the calculated feature amount with the reference information 12a stored in the storage unit 12 (step S15). For example, the control unit 11 performs comparison using a comparison method of various information such as the calculated feature amount and the correlation value of the reference information 12a. The control unit 11 functions as a comparison unit by executing a control program in step S15.

Next, the control unit 11 determines the presence or absence of an intruder into the vehicle C based on the comparison result of step S15 (step S16). For example, when the comparison is performed by calculating the correlation with the reference information 12a in step S15, the control unit 11 determines that there is an intruder when the correlation is equal to or less than a predetermined value. The predetermined value is, for example, 0.9. The control unit 11 functions as a detection unit by executing a control program in step S16.

If it is determined that there is an intruder (S16: YES), the control unit 11 outputs an alarm (step S17). For example, the control unit 11 may output a warning by sounding a horn of the vehicle C by in-vehicle communication such as CAN (Controller Area Network) communication, or output a warning by blinking the headlight of the vehicle C. May be. In addition, the control unit 11 is configured to be connectable to a communication network such as the Internet, and by notifying that the intruder is located in the passenger compartment through the communication network to the portable device possessed by the owner of the vehicle C. An alarm may be output. Thereafter, the control unit 11 finishes the process. On the other hand, when it determines with there being no intruder (S16: NO), the control part 11 complete | finishes a process, without outputting an alarm.

Next, the component calculation process will be described. In the component calculation process, the first A / D conversion process, the second A / D conversion process, the selection process, the first calculation process, and the second calculation process are performed in combination. FIG. 5 is an explanatory diagram for explaining the processing procedure of the component calculation processing.

In the component calculation process, first, the received radio signal and the input reference signal are converted into digital data by the first A / D conversion process and the second A / D conversion process, respectively. In the first A / D conversion process, the control unit 11 converts the radio signal received by each receiving antenna 1a into first digital data by the corresponding first A / D conversion unit 14a. In the second A / D conversion process, the control unit 11 converts the input reference signal into second digital data by the second A / D conversion unit 16. At this time, the control unit 11 synchronizes the first A / D conversion process and the second A / D conversion process. Further, the control unit 11 stores the first digital data and the second digital data converted in synchronization in association with a later-described conversion result table 131 (see FIG. 6) stored in the temporary storage unit 13.

Thereafter, a selection process is performed on the first digital data converted by the first A / D conversion process and the second digital data converted by the second A / D conversion process. In the selection process, the control unit 11 selects second digital data corresponding to the maximum point, the minimum point, and the zero cross point of the waveform of the reference signal. The maximum point is the phase of the reference signal that is an integer multiple of 90 degrees, and the minimum point is the phase of the reference signal that is an integer multiple of 270 degrees. The zero cross point is the center of the waveform of the reference signal. In the first embodiment, the value of the zero cross point is Vref. That is, in the selection process, the second digital data converted at each timing corresponding to an integral multiple of a quarter period of the reference signal is selected. In the selection process, the control unit 11 selects the first digital data converted in synchronization with each of the second digital data. Further, in the selection process, the control unit 11 stores the first digital data and the second digital data converted at timing synchronized with each other in a selection result table 132 (see FIG. 8) described later stored in the temporary storage unit 13. Store in association with each other.

Thereafter, in the component calculation process, a first calculation process and a second calculation process are performed. In the first calculation process, the control unit 11 multiplies the value of the first digital data and the value of the second digital data selected in the selection process and converted at a timing synchronized with each other. In the second calculation process, the control unit 11 uses the value of the second digital data used for the multiplication of the first calculation process as the value of the other first digital data different from the first digital data used for the multiplication of the first calculation process. Multiply by. The other first digital data is converted at a timing shifted by ¼ period of the reference signal as compared with the first digital data used for multiplication in the first calculation process. In this way, the second digital data is multiplied by the first digital data converted in synchronism with the first digital data converted at a timing shifted by a quarter cycle from the first digital data. Thus, each of the in-phase component and the quadrature component can be calculated.

Here, specific examples of the conversion result table 131, the selection result table 132, and the calculation result table 133 that are temporarily stored in the temporary storage unit 13 in the component calculation process are shown. 6 is an explanatory diagram showing a specific example of the conversion result table 131, FIG. 7 is an explanatory diagram conceptually showing the conversion result of the second A / D conversion process, and FIG. 8 is a specific example of the selection result table 132. FIG. 9 is an explanatory diagram showing a specific example of the calculation result table 133. Below, the example in case the receiver 1 is provided with the two receiving antennas 1a is shown. The first digital data obtained by converting the radio signal received by one receiving antenna 1a to the t-th in the first A / D conversion process is V11 [t], and the radio signal received by the other receiving antenna 1a is converted. The first digital data thus set is assumed to be V12 [t]. Further, the second digital data obtained by converting the reference signal to the t-th in the second A / D conversion process is represented as V2 [t].

As shown in FIG. 6, the conversion result table 131 stores the first digital data V11, V12 and the second digital data V2 for each timing number. The timing number represents the order converted by the first A / D conversion process or the second A / D conversion process. Further, as shown in FIG. 7, the value of the second digital data converted by the second A / D conversion process changes depending on the conversion timing. The value that the second digital data can take is within the range of values that the reference signal can take.

As shown in FIG. 8, the selection result table 132 stores first digital data V11 and V12 and second digital data V2 for each selection number. The selection number represents the order in which the control unit 11 selects the second digital data V2 from the conversion result table 131. The selection result table 132 stores second digital data corresponding to the maximum point, the minimum point, and the zero-cross point of the reference signal by the selection process. For example, V2 [3] in FIG. 8 is the second digital data selected as the maximum point of the reference signal by the control unit 11 as shown in FIG.

As shown in FIG. 9, the calculation result table 133 stores the in-phase component and the quadrature component of each receiving antenna 1a for each calculation number. The calculation number represents the order in which the control unit 11 calculates the in-phase component and the quadrature component. In the first calculation process, the control unit 11 multiplies the value of the first digital data and the value of the second digital data that have the same selection number in the selection result table 132, that is, converted at the same timing, to thereby obtain the in-phase component. calculate. In the second calculation process, the control unit 11 converts the first digital data converted from each other at a timing in which the value of the selection number is shifted by one in the selection result table 132, that is, shifted by ¼ period of the reference signal. And the quadrature component is calculated by multiplying the second digital data.

Next, the details of the processing procedure of the component calculation process will be described. Hereinafter, description will be made using the examples shown in FIGS. 6 to 9 as appropriate.

FIG. 10 is a flowchart showing a subroutine of component calculation processing. The control unit 11 of the receiving device 1 performs a first A / D conversion process and a second A / D conversion process (step S21). The control unit 11 instructs each of the first A / D conversion unit 14a and the second A / D conversion unit 16 to synchronize the radio signal and the reference signal with the first digital data and the second digital data at a predetermined sampling timing. To convert to At a predetermined sampling timing, for example, the control unit 11 causes the first A / D conversion unit 14a and the second A / D conversion unit 16 to convert the time corresponding to 1/10 of the cycle of the reference signal.

Next, the control unit 11 stores the converted first digital data and second digital data in the conversion result table 131 (step S22). The control unit 11 stores the first digital data and the second digital data converted in synchronization in the conversion result table 131 so that they have the same timing number. Thereafter, based on the second digital data stored in the conversion result table 131, the control unit 11 calculates the second digital data corresponding to the maximum point, the minimum point, and the zero cross point of the reference signal and the corresponding first digital data. A selection process is performed (step S23). As described above, in the selection process, the second digital data corresponding to the maximum point, the minimum point, and the zero-cross point are selected in association with the first digital data converted in synchronization with the second digital data. Store in the result table 132. Next, the control unit 11 performs a first calculation process based on the second digital data and the first digital data stored in the selection result table 132 (step S24), and then performs a second calculation process (step S25). . The control unit 11 stores the calculation result in the calculation result table 133 in each of the first calculation process and the second calculation process. Thereafter, the control unit 11 finishes the component calculation process. Note that the control unit 11 functions as a selection unit by executing a control program in step S23. Moreover, the control part 11 functions as a 1st calculation part by executing a control program by step S24. Furthermore, the control unit 11 functions as a second calculation unit by executing a control program in step S25.

FIG. 11 is a flowchart showing a subroutine of selection processing. The control unit 11 of the receiving device 1 secures the area of the counter n in the temporary storage unit 13, and sets the value of the counter n to 1 (step S31). Next, the control unit 11 initializes a flag (step S32). The flag is increased from the value of the second digital data converted earlier in the value of the second digital data converted later in the two second digital data in which the timing converted by the second A / D conversion process continues. It is information indicating whether or not it is decreasing. For example, when the second digital data converted later is increased from the previously converted second digital data, the flag value is 1, and when the second digital data is decreased, the flag value is −1. It is. For example, the control unit 11 secures a flag area in the temporary storage unit 13 and performs initialization by setting the value of the flag to 0.

Next, the control unit 11 reads the binary values V2 [n] and V2 [n + 1] from the conversion result table 131 of the temporary storage unit 13 (step S33). For example, when the value of the counter n is 1, the control unit 11 reads the binary values V2 [1] and V2 [2] from the conversion result table 131. Thereafter, the control unit 11 determines whether or not the read value of V2 [n + 1] is larger than the value of V2 [n] (step S34).

When it is determined that the value of V2 [n + 1] is larger than V2 [n] (S34: YES), the control unit 11 determines whether or not the value of the flag is a value indicating a decrease (step S35). For example, the control unit 11 determines whether or not the value of the flag is -1. When it determines with it not being a value which shows reduction (S35: NO), the control part 11 advances a process to step S37. If it is determined that the value indicates a decrease (S35: YES), the control unit 11 assumes that V2 [n] corresponds to the minimum point of the reference signal, and V2 [n] and the corresponding first digital data V11 [ n] and V12 [n] are stored in the selection result table 132 (step S36). Thereafter, the control unit 11 sets a value indicating an increase in the flag value, assuming that the value of V2 [n + 1] read in step S33 is increased from the value of V2 [n] (step S37). For example, the control unit 11 sets the value of the flag to 1.

On the other hand, when it is determined in step S34 that the value of V2 [n + 1] is equal to or less than the value of V2 [n] (S34: NO), the control unit 11 determines whether or not the flag value is an increase value. Determination is made (step S38). For example, the control unit 11 determines whether or not the value of the flag is 1. When it determines with it not being a value which shows increase (S38: NO), the control part 11 advances a process to step S40. When it is determined that the value indicates an increase (S38: YES), the control unit 11 assumes that V2 [n] corresponds to the maximum point of the reference signal, and V2 [n] and the corresponding first digital data V11 [ n] and V12 [n] are stored in the selection result table 132 (step S39). Thereafter, the control unit 11 sets a value indicating a decrease in the value of the flag, assuming that the value of V2 [n + 1] read in step S33 has decreased from the value of V2 [n] (step S40). For example, the control unit 11 sets the flag value to -1.

Here, in step S37 or step S40, a value indicating increase or a value indicating decrease is set as the flag value. In step S44 described later, the value of the counter n is updated so as to increase by one. That is, the value of the flag determined in the process of step S35 or step S38 is not a value based on the determination result in step S34 performed immediately before the process but a value based on the determination result in the previous step S34. For example, the flag value determined in step S35 or step S38 when the value of the counter n is 2 is the flag value set in step S37 or step S40 when the value of the counter n is 1.
Therefore, the control unit 11 determines in step S34 that the value of V2 [n] is larger than the value of V2 [n + 1], and in step S35, the value of V2 [n] decreases from the value of V2 [n−1]. It is assumed that V2 [n] is a local minimum point when it is determined that the value of the flag is set. For example, when each of the second digital data converted by the second A / D conversion process has a value as shown in FIG. 7, the control unit 11 assumes that V2 [7] and V2 [17] are minimum points, In step S36, it is stored in the selection result table 132.
Further, the control unit 11 determines in step S34 that the value of V2 [n] is less than or equal to the value of V2 [n + 1], and in step S35, the value of V2 [n] increases from the value of V2 [n−1]. It is assumed that V2 [n] is the maximum point when it is determined that the value of the flag is set. For example, when each of the second digital data converted by the second A / D conversion process has a value as shown in FIG. 7, the control unit 11 assumes that V2 [3] and V2 [12] are maximum points, In step S36, it is stored in the selection result table 132.

After performing the process of step S37 or step S40, the controller 11 determines whether or not V2 [n] is the second digital data corresponding to the center of the waveform of the reference signal, that is, the zero cross point (step S41). . For example, when the value of V2 [n] is smaller than Vref and the value of V2 [n + 1] is larger than Vref, the control unit 11 determines that the second digital data corresponds to the zero cross point. In addition, for example, when the value of V2 [n] is larger than Vref and the value of V2 [n + 1] is smaller than Vref, the control unit 11 also provides second digital data in which V2 [n] corresponds to the zero cross point. It is determined that For example, when each of the second digital data converted by the second A / D conversion process has a value as shown in FIG. 7, the control unit 11 sets V2 [5], V2 [9], and V2 [15]. The second digital data corresponding to the zero cross point is determined.

If it is determined that the second digital data does not correspond to the zero cross point (S41: NO), the control unit 11 advances the process to step S43. When it is determined that the second digital data corresponds to the zero cross point (S41: YES), the control unit 11 selects V2 [n] and the corresponding first digital data V11 [n], V12 [n] as the selection result table 132. (Step S42).

Next, the control unit 11 determines whether the selection of the second digital data corresponding to the maximum point, the minimum point, and the zero cross point is completed (step S43). For example, the control unit 11 makes a determination based on whether or not all the second digital data stored in the conversion result table 131 has been read at least once. If it is determined that the selection has not been completed (S43: NO), the control unit 11 increments the counter n by 1 (step S44), and returns the process to step S33. When it determines with selection having been completed (S43: YES), the control part 11 finishes a selection process.

FIG. 12 is a flowchart showing a subroutine of the first calculation process. The control unit 11 of the receiving device 1 secures the area of the counter i in the temporary storage unit 13, and sets 1 to the value of the counter i (step S51). Next, the control unit 11 reads out the i-th first digital data and the i-th second digital data with the selection number from the selection result table 132, and multiplies the read values (step S52). For example, when the value of the counter i is 1, the control unit 11 multiplies one value of V11 [3] or V12 [3] by the value of V2 [3]. Then, the control part 11 memorize | stores the calculation result of step S52 in the calculation result table 133 as an in-phase component (step S53).

Next, the control unit 11 determines whether or not the first digital data for all antennas whose selection numbers in the selection result table 132 are stored in the i-th row are multiplied with the second digital data stored in the i-th row. Is determined (step S54). When it determines with not multiplying all antennas (S54: NO), the control part 11 returns a process to step S52. For example, when the control unit 11 multiplies the value of V11 [3] and the value of V2 [3] by the process of the previous step S52, the value of V12 [3] and V2 [3] by the process of the next step S52. Multiply by the value of.

If it is determined that all antennas have been multiplied (S54: YES), the control unit 11 determines whether all multiplications have been completed (step S55). For example, the control unit 11 determines whether or not multiplication of all the first digital data stored in the selection result table 132 with the corresponding second digital data is completed. When it is determined that the full multiplication has not been completed (S55: NO), the control unit 11 increments the counter i by 1 (step S56), and returns the process to step S52. When it is determined that all multiplications have been completed (S55: YES), the control unit 11 ends the first calculation process.

FIG. 13 is a flowchart showing a subroutine of the second calculation process. The control unit 11 of the receiving device 1 secures the area of the counter j in the temporary storage unit 13, and sets 1 to the value of the counter j (step S61). Next, the control unit 11 reads the first digital data with the selection number j + 1 and the second digital data with the jth from the selection result table 132, and multiplies the read values (step S62). For example, when the value of the counter j is 1, the control unit 11 multiplies one value of V11 [5] or V12 [5] by the value of V2 [3]. Then, the control part 11 memorize | stores the calculation result of step S62 in the calculation result table 133 as an orthogonal component (step S63).

Next, the control unit 11 determines whether or not the first digital data for all antennas whose selection numbers in the selection result table 132 are stored in the (j + 1) th row are multiplied with the second digital data stored in the jth. Is determined (step S64). When it determines with not multiplying all antennas (S64: NO), the control part 11 returns a process to step S62. For example, when the control unit 11 multiplies the value of V11 [5] and the value of V2 [3] in the process of the previous step S62, the value of V12 [5] and V2 [3] in the process of the next step S62. Multiply by the value of.

If it is determined that all antennas have been multiplied (S64: YES), the control unit 11 determines whether all multiplications have been completed (step S65). For example, the control unit 11 determines whether all the second digital data stored in the selection result table 132 have been multiplied with the corresponding first digital data. When it is determined that the full multiplication has not been completed (S65: NO), the control unit 11 increments the counter j by 1 (step S66), and returns the process to step S62. When it is determined that all multiplications have been completed (S65: YES), the control unit 11 ends the second calculation process.

In the second calculation process of the first embodiment, it has been described that the j + 1-th first digital data and the j-th second digital data are multiplied in step S62. However, the j-th first digital data and the j + 1-th digital data are described. The second digital data may be multiplied. That is, in the second calculation process, the control unit 11 uses the value of the second digital data different from the second digital data used for the multiplication of the first calculation process to the first digital data used for the multiplication of the first calculation process. Multiply the data value. The other second digital data is converted at a timing shifted by ¼ period of the reference signal as compared with the second digital data used for the multiplication in the first calculation process. Even in this case, the control unit 11 can calculate the orthogonal component.

With the above configuration and processing, the receiving apparatus 1 calculates digital data representing the waveform of each signal when the received analog signal is separated into two signals whose phases are orthogonal to each other without using a quadrature detector. Can do. Therefore, the number of parts required for acquiring the digital data can be reduced. Further, digital data representing the waveform of each signal can be calculated using the first digital data and the second digital data selected by the selection process. Therefore, it is possible to reduce the processing load when acquiring the digital data.

Also, for example, by selecting a periodic signal when the phase is 90 degrees, 180 degrees, 270 degrees, and 360 degrees, the maximum point, the minimum point, and the center point of the reference signal can be acquired. By acquiring each point in the selection process, it is possible to select the second digital data representing the outline of the reference signal and the first digital data converted in synchronization with the second digital data. . Therefore, the value of the digital data calculated in the first calculation process and the second calculation process can be made closer to the value of each signal when the received analog signal is separated into two signals whose phases are orthogonal to each other.

In addition, the receiving device 1 can detect a change in state within the communication range with the transmitting device 2. In the first embodiment, the example in which the receiving device 1 detects the presence or absence of an intruder in the cabin of the vehicle C has been described. However, if the event occurs within the communication range with the transmitting device 2, the vehicle 1 Other events occurring inside the room may be detected, or other events occurring outside the vehicle compartment may be detected.
For example, the receiving device 1 may detect whether a person approaches the vehicle C as an event that has occurred outside the passenger compartment. At this time, the reference information 12a stored in the storage unit 12 of the receiving device 1 is, for example, wireless when the receiving antenna 1a receives the wireless signal transmitted from the transmitting device 2 in the state where there is no person around the vehicle C. Information related to the arrival angle of the signal and information related to the delay profile. At this time, in step S <b> 16 in FIG. 4, the control unit 11 of the receiving device 1 determines whether or not a person approaches the vehicle C by the same process as described above. If it is determined in step S16 that there is a person approaching (S16: YES), the control unit 11 is convenient when getting on the vehicle C, such as turning on an interior lamp for lighting of the vehicle C (not shown). Vehicle control that can improve performance.

In the component calculation process in the first embodiment, as illustrated in FIG. 10, it has been described that the second calculation process is performed after the first calculation process is performed, but the second calculation process is performed. The first calculation process may be performed later. Further, the first calculation process and the second calculation process may be performed in parallel.

(Embodiment 2)
In the first embodiment, the receiving device 1 uses the reference signal output from the transmitting device 2 and digital data representing the waveform of each signal when the radio signal from the transmitting device 2 is separated into two signals whose phases are orthogonal to each other. Was calculated. In the second embodiment, an example in which the receiving device 1 generates a reference signal and calculates the second digital data will be described. Since the other configurations and operations except the configurations and operations described below are the same as those in the first embodiment, detailed description on the same configurations and descriptions of the operations and effects are omitted for the sake of brevity.

In the communication system according to Embodiment 2, the receiving device 1 and the transmitting device 2 are not connected by the communication line 3. In the first embodiment, transmission of a radio signal from the transmission device 2 to the reception device 1 has been described. However, in the second embodiment, a radio signal is further transmitted from the reception device 1 to the transmission device 2. Therefore, in addition to the configuration described in the first embodiment, the transmission device 2 includes a reception antenna for receiving a radio signal and a reception unit that outputs the radio signal received from the reception antenna to the control unit 21.

Next, the receiving device 1 according to the second embodiment will be described. FIG. 14 is a block diagram illustrating a configuration of the receiving device 1 according to the second embodiment. The receiving device 1 according to the second embodiment does not include the input / output unit 17 but includes the transmitting unit 18 and the oscillation circuit 19. The transmission unit 18 is connected to the control unit 11 via a bus, and transmits a radio signal from a transmission antenna (not shown) according to an instruction from the control unit 11. The oscillation circuit 19 is connected to the second A / D conversion unit 16, generates a reference signal according to an instruction from the control unit 11, and outputs the reference signal to the second A / D conversion unit 16. The second A / D converter 16 converts the reference signal from the oscillation circuit 19 into second digital data.

FIG. 15 is a flowchart showing the processing procedure of the receiving apparatus 1 when detecting entry into the vehicle interior. Note that the processing from step S74 to step S78 in FIG. 15 is the same as the processing from step S13 to step S17 in FIG.

The control unit 11 of the reception device 1 wirelessly transmits a transmission request for a wireless signal for detecting an event occurring in the passenger compartment of the vehicle C to the transmission device 2 (step S71). Thereafter, the control unit 11 determines whether or not a radio signal is received from the transmission device 2 that has received the transmission request (step S72). When it determines with not receiving the radio signal (S72: NO), the control part 11 waits until a radio signal is received.

If it is determined that a radio signal has been received (S72: YES), the control unit 11 generates a reference signal corresponding to the oscillation circuit 19 corresponding to the received radio signal (step S73). For example, the control unit 11 stores in advance information related to the phase of a radio signal transmitted by the transmission device 2, and causes the oscillation circuit 19 to generate a reference signal based on the information. Thereafter, the control unit 11 advances the process to step S74 and subsequent steps using the received wireless signal and the reference signal generated by the oscillation circuit 19.

With the above-described configuration and processing, the receiving device 1 does not connect the transmitting device 2 via the communication line 3, and the waveform of each signal when the received analog signal is separated into two signals whose phases are orthogonal to each other is obtained. Representing digital data can be calculated.

(Modification)
In the modification, an example will be described in which a subroutine for selection processing is executed in a processing procedure different from the processing procedure shown in FIG. Since the other configurations and operations except for the configurations and operations described below are the same as those in the first and second embodiments, a detailed description of the same configuration and a description of the operations and effects are omitted for the sake of brevity. .

FIG. 16 is a flowchart showing a subroutine of selection processing in the modification. The control unit 11 of the receiving device 1 secures the area of the counter n in the temporary storage unit 13 and sets the value of the counter n to 2 (step S81). Next, the control unit 11 reads the three values V2 [n−1], V2 [n], and V2 [n + 1] from the conversion result table 131 in the temporary storage unit 13 (step S82). For example, when the value of the counter n is 2, the control unit 11 reads out the three values V2 [1], V2 [2], and V2 [3] from the conversion result table 131.

Thereafter, the control unit 11 performs a maximum point determination process using the read three values of V2 [n−1], V2 [n], and V2 [n + 1] (step S83). The maximum point determination process is a process for determining whether or not V2 [n] is the second digital data corresponding to the maximum point of the waveform of the reference signal. For example, the control unit 11 has a value of V2 [n]. When it is larger than the values of V2 [n−1] and V2 [n + 1], it is determined that V2 [n] is a local maximum point. For example, when each of the second digital data converted by the second A / D conversion process has a value as shown in FIG. 7, the control unit 11 corresponds to V2 [3] and V2 [12] as local maximum points. It determines with it being 2nd digital data.

Next, the control unit 11 determines whether or not V2 [n] is the second digital data corresponding to the maximum point by the maximum point determination process (step S84). When it is determined that V2 [n] is the second digital data corresponding to the maximum point (S84: YES), the control unit 11 determines whether or not V2 [n] is already stored in the selection result table 132. (Step S85). When it determines with having memorize | stored (S85: YES), the control part 11 advances a process to step S91. When it is determined that it has not been stored (S85: NO), the control unit 11 stores V2 [n] and the corresponding first digital data V11 [n], V12 [n] in the selection result table 132 (step S86). Thereafter, the process proceeds to step S91.

When it is determined that V2 [n] is not the second digital data corresponding to the maximum point (S84: NO), the control unit 11 determines the three values V2 [n−1], V2 [n], and V2 [n + 1]. The minimum point determination process is performed using (Step S87). The minimum point determination process is a process for determining whether or not V2 [n] is second digital data corresponding to the minimum point of the waveform of the reference signal. For example, the control unit 11 has a value of V2 [n]. When the value is smaller than the values of V2 [n−1] and V [n + 1], it is determined that the value of V2 [n] is a minimum point. For example, when each of the second digital data converted by the second A / D conversion process has a value as shown in FIG. 7, the control unit 11 corresponds to V2 [7] and V [17] as minimum points. It determines with it being 2nd digital data.

Next, the control unit 11 determines whether or not V2 [n] is the second digital data corresponding to the minimum point by the minimum point determination process (step S88). When it is determined that V [n] is the second digital data corresponding to the minimum point (S88: YES), the control unit 11 advances the process to step S85.

When it is determined that V2 [n] is not the second digital data corresponding to the minimum point (S88: NO), the control unit 11 calculates the three values V2 [n−1], V2 [n], and V2 [n + 1]. The zero-cross point determination process is performed using them (step S89). The process of step S89 is the same as the process of step S41 in FIG.

Next, the control unit 11 determines whether or not V [n] is the second digital data corresponding to the zero cross point by the zero cross point determination process (step S90). When it is determined that V2 [n] is the zero cross point (S90: YES), the process proceeds to step S85.

When it is determined that V2 [n] is not the second digital data corresponding to the zero cross point (S90: NO), the control unit 11 has completed the selection of the second digital data corresponding to the maximum point, the minimum point, and the zero cross point. It is determined whether or not (step S91). For example, the control unit 11 may determine whether all the second digital data stored in the conversion result table 131 has been read at least once, or in step S86 by a predetermined selection number. The determination may be made based on whether or not processing has been performed. If it is determined that the selection has not been completed (S91: NO), the control unit 11 increments the counter n by 1 (step S92), and the process returns to step S82. When it determines with selection having been completed (S91: YES), the control part 11 finishes a selection process.

The control unit 11 can select the second digital data corresponding to the maximum point, the minimum point, and the zero cross point even when the selection process is performed according to the above processing procedure. Note that the processing procedure of the selection processing subroutine described above is only an example, and any processing procedure can be used as long as the second digital data corresponding to the maximum point, the minimum point, and the zero-cross point of the reference signal can be selected. Needless to say, the processing procedure may be other than that shown in FIG.

In addition, although the communication system in

Embodiment

1 and 2 and a modification demonstrated detecting the event which generate | occur | produced in the vehicle interior of the vehicle C, it may be comprised so that the event which occurred in the other indoor space may be detected. Good.

It should be considered that the embodiment disclosed this time is illustrative in all respects and not restrictive. The scope of the present invention is defined not by the above-described meaning but by the scope of claims, and is intended to include all modifications within the meaning and scope equivalent to the scope of claims.

DESCRIPTION OF SYMBOLS 1 Reception apparatus 1a Reception antenna 2 Transmission apparatus 2a Transmission antenna 3 Communication line 4 Recording medium 4a Control program 11 Control part (selection part, 1st calculation part, 2nd calculation part)
DESCRIPTION OF SYMBOLS 12 Memory | storage part 12a Reference | standard information 13 Temporary memory | storage part 14 Reception part 14a 1st A / D conversion part 15 Reading part 16 2nd A / D conversion part 17 Input / output part 18 Transmission part 19 Oscillation circuit 21 Control part 22 Storage part 23 Temporary storage part 24 transmitter 25 output unit

Claims

The waveform of each signal when an analog signal is received and the analog signal is separated into a first signal and a second signal whose phases are orthogonal to each other based on the received analog signal and an analog periodic signal corresponding to the analog signal A receiving device for calculating digital data representing
A first A / D converter that converts the received analog signal into first digital data;
A second A / D converter that converts the periodic signal into second digital data in synchronization with the first A / D converter;
Of the second digital data converted by the second A / D converter, the second digital data converted at each timing corresponding to the time when an integral multiple of ¼ period of the periodic signal has elapsed from a predetermined time, and A selection unit for selecting the first digital data converted in synchronization with each of the second digital data;
A digital data representing the waveform of the first signal is calculated by multiplying the value of the first digital data and the value of the second digital data selected by the selection unit and converted at an arbitrary timing synchronized with each other. 1 calculation unit;
Multiply the value of the first digital data converted at the arbitrary timing and the value of the second digital data selected by the selection unit and converted at one timing continuous to the arbitrary timing, or the arbitrary A second calculation unit that calculates digital data representing the waveform of the second signal by multiplying the value of the second digital data converted at the timing of the first digital data and the value of the first digital data converted at the one timing And a receiving device.
The periodic signal has a sinusoidal shape having an initial phase corresponding to the analog signal,
The selection unit selects at least the second digital data corresponding to the value of the periodic signal when the phase is 90 degrees or 270 degrees, and the first digital data converted in synchronization with the second digital data. The receiving device according to claim 1.
With multiple receiving antennas,
The digital data representing the waveform of each signal when the analog signals received by the plurality of receiving antennas are separated into a first signal and a second signal whose phases are orthogonal to each other is calculated. The receiving device described.
A receiving device according to any one of claims 1 to 3,
A transmitter for transmitting an analog signal,
The receiving device receives the analog signal transmitted from the transmitting device, and calculates digital data representing the waveform of each signal when the received analog signal is separated into a first signal and a second signal whose phases are orthogonal to each other There is a communication system.
Based on an arbitrary analog signal and an analog periodic signal corresponding to the analog signal, digital data representing the waveform of each signal when the analog signal is separated into a first signal and a second signal whose phases are orthogonal to each other is calculated. A calculation method for
A first A / D conversion step of converting the analog signal into first digital data;
A second A / D conversion step for converting the periodic signal into second digital data in synchronization with the first A / D conversion step;
Second digital data converted at each timing corresponding to a time point at which an integral multiple of ¼ period of the periodic signal has elapsed from a predetermined time point among the second digital data converted in the second A / D conversion step, And a selection step of selecting the first digital data converted in synchronism with each of the second digital data,
The digital data representing the waveform of the first signal is calculated by multiplying the value of the first digital data and the value of the second digital data selected at the selection step and converted at an arbitrary timing synchronized with each other. 1 calculation step;
Multiply the value of the first digital data converted at the arbitrary timing and the value of the second digital data selected by the selection unit and converted at one timing continuous to the arbitrary timing, or the arbitrary A second calculation step of calculating digital data representing the waveform of the second signal by multiplying the value of the second digital data converted at the timing of the first digital data and the value of the first digital data converted at the one timing. A calculation method including and.
Based on an arbitrary analog signal and an analog periodic signal corresponding to the analog signal, the computer calculates digital data representing the waveform of each signal when the analog signal is separated into two signals whose phases are orthogonal to each other. A computer program,
The computer,
A first A / D converter that converts the analog signal into first digital data;
A second A / D converter that converts the periodic signal into second digital data in synchronization with the first A / D converter;
Of the second digital data converted by the second A / D converter, the second digital data converted at each timing corresponding to the time when an integral multiple of ¼ period of the periodic signal has elapsed from a predetermined time, and A selection unit for selecting the first digital data converted in synchronization with each of the second digital data;
A digital data representing the waveform of the first signal is calculated by multiplying the value of the first digital data and the value of the second digital data selected by the selection unit and converted at an arbitrary timing synchronized with each other. 1 calculation unit;
Multiply the value of the first digital data converted at the arbitrary timing and the value of the second digital data selected by the selection unit and converted at one timing continuous to the arbitrary timing, or the arbitrary A second calculation unit that calculates digital data representing the waveform of the second signal by multiplying the value of the second digital data converted at the timing of the first digital data and the value of the first digital data converted at the one timing A computer program that functions as a computer.