Identification system, identification device, and wire harness

Abstract

This identification system comprises: a wire harness which includes an electric wire and a reflection part that reflects a signal flowing through the electric wire; and an identification device which is connected to the wire harness and which identifies the wire harness on the basis of a reflection signal from the reflection part. The reflection part is provided with a plurality of open stubs. The reflection signal contains an identification code corresponding to the plurality of open stubs. The identification code is for identifying the wire harness. The identification device comprises a signal generation circuit for sending a signal to the electric wire and a read circuit for reading the identification code from the reflection signal, which is based on a reflected wave from the reflection part.

Description

Identification system, identification device, and wire harness

[0001] This application claims priority to Japanese Patent Application No. 2024-016755, filed February 7, 2024, and incorporates by reference all of the contents of that application.

[0002] Vehicles are equipped with various on-board devices. These devices include various ECUs (Electronic Control Units) that control functions necessary for the vehicle, such as steering and braking. These ECUs are connected to each other to form a network. Each ECU communicates with each other via this network to realize basic vehicle functions, such as "driving," "turning," and "stopping." Wiring harnesses are usually used to connect the on-board devices.

[0003] Such in-vehicle devices require technology to prevent hacking or data tampering of the in-vehicle devices (ECUs).Patent Document 1, listed below, proposes a connector system for preventing communication between a wire harness and unintended devices.

[0004] The connector system described in Patent Document 1 includes a first connector and a second connector connected thereto. The second connector includes a processing unit that creates verification information and transmits it to the first connector. The first connector includes a verification unit that verifies the second connector based on the verification information received from the second connector. The verification unit determines that verification has failed if it is unable to receive the verification information. The first connector further includes a switch that, when connected to the second connector, switches between electrically connecting the transmission line in the first connector and the transmission line in the second connector, and a control unit that controls the switch based on the verification results of the verification unit.

[0005] If the second connector is an unauthorized connector, the verification unit of the first connector determines that the verification has failed. The control unit of the first connector maintains the switch in the off state. This interrupts the electrical connection between the transmission line of the first connector and the transmission line of the second connector. This prevents communication between the wire harness and unintended devices, ensuring the security of communication between devices.

[0006] International Publication No. 2019 / 187349

[0007] According to an aspect of the present disclosure, there is provided an identification system including: a wire harness including electric wires and a reflector that reflects a signal flowing through the electric wires; and an identification device connected to the wire harness and configured to identify the wire harness based on a reflected signal from the reflector. The reflector includes a plurality of open stubs, and the reflected signal includes an identification code corresponding to the plurality of open stubs, the identification code being a code that identifies the wire harness. The identification device includes a signal generating circuit that transmits the signal to the electric wires, and a reading circuit that reads the identification code from the reflected signal based on a wave reflected from the reflector.

[0008] The present disclosure can be realized not only as an identification system, an identification device, and a wire harness that include such characteristic configurations, but also as other systems or devices that include an identification system, an identification device, or a wire harness.

[0009] FIG. 1 is a diagram illustrating an identification system according to a first embodiment. FIG. 2 is a block diagram illustrating a configuration example of a first in-vehicle device illustrated in FIG. 1. FIG. 3 is a block diagram illustrating a configuration example of the identification system illustrated in FIG. 1. FIG. 4 is a block diagram illustrating a configuration example of the first in-vehicle device illustrated in FIG. 1. FIG. 5 is a diagram illustrating an example of an open stub. FIG. 6 is a diagram illustrating a configuration example of the identification system illustrated in FIG. 1. FIG. 7 is a diagram illustrating a configuration example of a reflection unit in the identification system illustrated in FIG. 6. FIG. 8 is a diagram illustrating a configuration example of a shift register in the identification system illustrated in FIG. 1. FIG. 9 is a diagram illustrating an example of a shift register. FIG. 10 is a diagram illustrating an example of a timing chart of the shift register illustrated in FIG. 9. FIG. 11 is a block diagram illustrating a configuration example of an identification system according to a second embodiment. FIG. 12 is a diagram illustrating an example of a register in the identification system illustrated in FIG. 11. FIG. 13 is a diagram illustrating an example of a register. FIG. 14 is a diagram illustrating an example of a timing chart of the register illustrated in FIG. 13. FIG. 15 is a block diagram illustrating a configuration example of an identification system according to a third embodiment. FIG. 16 is a diagram illustrating the configuration example of the identification system illustrated in FIG. 15. FIG. 17 is a diagram for explaining a configuration example of a reflector in the identification system of FIG. 16 . FIG. 18 is a block diagram showing a configuration example of an identification system according to a fourth embodiment. FIG. 19 is a diagram for explaining a configuration example of the identification system shown in FIG. 18 . FIG. 20 is a diagram for explaining a configuration example of a reflector in the identification system of FIG. 19 . FIG. 21 is a plan view for explaining a configuration example of a wire harness according to a fifth embodiment. FIG. 22 is a perspective view for explaining a configuration example of a wire harness according to a sixth embodiment. FIG. 23 is a diagram for explaining an example of a manufacturing method of a wire harness according to the sixth embodiment. FIG. 24 is a diagram for explaining an example of a manufacturing method of a wire harness according to the sixth embodiment. FIG. 25 is a diagram for explaining an example of a manufacturing method of a wire harness according to the sixth embodiment. FIG. 26 is a diagram for explaining a configuration example of a reflector in the wire harness according to the sixth embodiment. FIG. 27 is a diagram for explaining a configuration example and a manufacturing method of a wire harness according to a seventh embodiment.FIG. 28 is a diagram for explaining an example of a configuration and a manufacturing method of a wire harness according to a seventh embodiment. FIG. 29 is a diagram for explaining an identification device according to an eighth embodiment. FIG. 30 is a block diagram showing an example of a configuration of the identification device shown in FIG. 29. FIG. 31 is a diagram showing an identification system according to a ninth embodiment. FIG. 32 is a block diagram of the identification system according to the ninth embodiment. FIG. 33 is a diagram showing details of the identification system of FIG. 32. FIG. 34 is a diagram showing a passive element unit of the ninth embodiment. FIG. 35 is a block diagram of an identification system according to a tenth embodiment. FIG. 36 is a diagram showing details of the identification system of FIG. 35. FIG. 37 is a partially enlarged view of the passive element unit. FIG. 38A is a diagram illustrating a portion of the frequency characteristics of a transmitted signal in the tenth embodiment. FIG. 38B is a diagram showing another example of a portion of the frequency characteristics of a transmitted signal in the tenth embodiment.

[0010] The connector system described in Patent Document 1 is an excellent system in terms of ensuring security. However, because the processing unit, verification unit, and control unit are realized by electronic devices, and the electronic devices and switches are built into the connector, it is difficult to simplify the configuration. As a result, manufacturing costs tend to be high.

[0011] The present disclosure has been made to solve such problems, and one object of the present disclosure is to provide an identification system, an identification device, and a wire harness that contribute to improving communication security with a simple configuration.

[0012] Effect of the Present Disclosure According to the present disclosure, it is possible to provide an identification system, an identification device, and a wire harness that contribute to improving communication security with a simple configuration.

[0013] [Description of Embodiments of the Present Disclosure] Preferred embodiments of the present disclosure will be listed and described below. At least some of the embodiments described below may be combined in any combination.

[0014] [Summary of the embodiment] (1) An identification system according to a first aspect of the present disclosure includes: a wire harness including an electric wire and a reflecting portion that reflects a signal flowing through the electric wire; and an identification device connected to the wire harness and that identifies the wire harness based on a reflected signal from the reflecting portion, wherein the reflecting portion includes a plurality of open stubs, the reflected signal includes an identification code corresponding to the plurality of open stubs, and the identification code is a code that identifies the wire harness; and the identification device includes: a signal generating circuit that transmits the signal to the electric wire; and a reading circuit that reads the identification code from the reflected signal that is based on a wave reflected from the reflecting portion.

[0015] The reflecting section includes a plurality of open stubs that reflect a signal. The plurality of open stubs are configured so that the reflected signal includes an identification code for identifying the wire harness. The identification device identifies the connected wire harness by reading the identification code from the reflected signal. This makes it possible to determine whether a normal wire harness is connected, thereby improving communication security with a simple configuration.

[0016] (2) In the above (1), the reflector may be configured so that the reflected signal includes an identification code for identifying the wire harness based on a combination of the presence or absence of the open stub, thereby making it possible to easily generate an identification code for identifying the wire harness.

[0017] (3) In the above (1) or (2), the reading circuit may include a directional coupler that extracts the reflected wave reflected by the reflecting portion, and a wave detector that detects the reflected wave from the directional coupler, thereby facilitating identification of the wire harness.

[0018] (4) In the above (3), the electric wire may have a plurality of positions, the plurality of positions to which the open stubs can be electrically connected in accordance with the identification code and may be arranged at equal intervals on the electric wire, the number of the plurality of open stubs may be less than the number of the plurality of positions, the plurality of open stubs may have equal electrical lengths and may be electrically connected to any of the plurality of positions, and the reading circuit may further include a register that latches the reflected wave from the detector to extract the identification code from the reflected signal, thereby making it easier to read the identification code.

[0019] (5) In the above (4), the register may be configured to serially latch the reflected waves, which makes it easier to read the identification code.

[0020] (6) In the above (4), the register may be configured to latch the reflected signals in parallel, which also makes it easier to read the identification code.

[0021] (7) In the above (3), the electric wire may have a plurality of positions, and the plurality of positions may be capable of electrically connecting the open stubs according to the identification code. The number of the plurality of open stubs may be less than the number of the plurality of positions, and the plurality of open stubs may be electrically connected to any of the plurality of positions so that the electrical length of the open stub increases with increasing distance from the directional coupler. This may suppress the mixing of reflections from each open stub, thereby reducing the output of the signal transmitted from the signal generating circuit. As a result, power can be used more effectively when transmitting the signal.

[0022] (8) In the above (7), the directional coupler may include a plurality of couplers having different electrical lengths, and when the open stub is formed at any of the plurality of positions, the plurality of couplers may have an electrical length equal to the electrical length of any of the open stubs, and the plurality of couplers may be further arranged so that the electrical lengths of the couplers increase with increasing distance from the reflecting portion. This makes it easier to extract a reflected signal from the reflection of each open stub.

[0023] (9) In the above (8), a plurality of the detectors may be provided corresponding to the plurality of couplers. This allows the identification code to be distinguished in the frequency axis direction, making it easier to read the identification code.

[0024] (10) In any of (7) to (9) above, the plurality of open stubs may be formed so that the electrical lengths of the open stubs are ¼ wavelength of the fundamental wave of the signal transmitted by the signal generating circuit and ¼ wavelength of an odd multiple of the fundamental wave. This makes it easy to suppress the mixing of reflections from each open stub, and therefore it is easy to reduce the output of the signal transmitted from the signal generating circuit. As a result, power can be used more effectively when transmitting the signal.

[0025] (11) In any one of the above (1) to (10), the reflecting portion may be a separate member from the electric wire, provided along the electric wire, and may include a connection portion connected to the electric wire, and the plurality of open stubs provided integrally with the connection portion. This makes it possible to easily provide the reflecting portion in the wire harness.

[0026] (12) An identification device according to a second aspect of the present disclosure is an identification device for identifying a wire harness, and includes: a signal generating circuit connected to the wire harness and transmitting a predetermined signal to electric wires of the wire harness; and a reading circuit reading an identification code for identifying the wire harness from a reflected signal based on a reflected wave of the signal from the wire harness.

[0027] Such an identification device can read the identification code with a simple configuration, thereby easily improving communication security.

[0028] (13) A wire harness according to a third aspect of the present disclosure includes an electric wire and a reflecting portion that reflects a signal flowing through the electric wire, the reflecting portion including a plurality of open stubs configured such that a reflected signal from the reflecting portion includes an identification code for identifying the wire harness.

[0029] Such a wire harness can improve communication security with a simple configuration.

[0030] (14) In the above (13), the reflecting portion may be a separate member from the electric wire, provided along the electric wire, and may include a connection portion connected to the electric wire, and the plurality of open stubs provided integrally with the connection portion. This makes it possible to easily provide the reflecting portion in the wire harness.

[0031] (15) In the above (13) or (14), the electric wire may be a first electric wire not used for communication, and the wiring harness may further include a second electric wire used for communication. This increases the degree of freedom in designing the reflecting portion.

[0032] (16) In any one of the above (13) to (15), the wire harness may further include a sheet-like holding member that holds the electric wires. This makes it possible to obtain a flat wire harness that can improve communication security with a simple configuration.

[0033] (17) An identification system according to a fourth aspect of the present disclosure includes a wire harness including an electric wire and a passive element unit provided between a first end and a second end of the electric wire, and an identification device that identifies the wire harness based on an identification signal obtained from the electric wire. The identification signal is either a reflected signal obtained at the first end when a predetermined signal is input from the first end, or a transmitted signal obtained at the second end when the predetermined signal is input from the first end. The passive element unit includes a plurality of open stubs. The combination of electrical lengths of the plurality of open stubs or the arrangement of the plurality of open stubs is unique. Because the passive element unit of the above configuration includes a plurality of open stubs, the reflected signal and transmitted signal, which are identification signals, are affected by the combination of electrical lengths of the plurality of open stubs or the arrangement of the plurality of open stubs. Because the combination of electrical lengths of the plurality of open stubs or the arrangement of the plurality of open stubs is unique, the influence on the reflected signal and transmitted signal is also unique. Therefore, the connected wire harness can be identified by the reflected signal and transmitted signal. This makes it possible to determine whether or not a normal wire harness is connected, thereby improving communication security with a simple configuration.

[0034] (18) In the above (17), the reflected signal and the transmitted signal may include an identification code based on a combination of the electrical lengths of the plurality of open stubs or an arrangement of the plurality of open stubs. In this case, the unique combination of the electrical lengths of the plurality of open stubs or the arrangement of the plurality of open stubs serves as the identification code.

[0035] (19) In the above (17) or (18), the combination of the electrical lengths of the plurality of open stubs may include a plurality of electrical lengths corresponding to some of the plurality of signal components included in the predetermined signal. In this case, the identification code can be represented by the plurality of signal components in the reflected signal and the transmitted signal.

[0036] (20) In the above (18), the identification device may include a directional coupler capable of extracting multiple signal components contained in the predetermined signal from the identification signal, and an acquisition unit that acquires the identification code based on an output of the directional coupler. In this case, the identification code represented by the multiple signal components can be acquired from the identification signal.

[0037] (21) In the above (20), the directional coupler may be capable of extracting the plurality of signal components from the reflected signal. In this case, the identification device can obtain an identification code from the reflected signal.

[0038] (22) In the above (18), when the combination of the electrical lengths of the plurality of open stubs includes a plurality of electrical lengths corresponding to some of the plurality of signal components included in the predetermined signal, the predetermined signal includes a square wave, the plurality of signal components include a fundamental wave component of the predetermined signal and harmonic components having frequencies that are odd multiples of the fundamental wave frequency, and the electrical lengths of the plurality of open stubs are ¼ wavelength of the some of the plurality of signal components corresponding to the plurality of open stubs, the identification device may obtain the transmitted signal from a position on the electric wire that is closer to the second end than the passive element unit. In this case, the identification device can obtain an identification code from the transmitted signal.

[0039] (23) In the above (22), when the multiple open stubs each have a stub body and a directional coupling portion connecting the electric wire and the stub body, the directional coupling portion may be configured to extract a signal component corresponding to each of the multiple open stubs. In this case, the multiple open stubs can be made to function by coupling the directional coupling portion to the electric wire. This makes it easy to configure the passive element portion 1090 and the wire harness separately. Furthermore, by adjusting the gap between the electric wire and the directional coupling portion, the filter characteristics of the multiple open stubs can be adjusted, thereby increasing the degree of freedom in designing the multiple open stubs.

[0040] (24) In the above (22) or (23), the identification device may include a directional coupler capable of extracting the plurality of signal components from the transmitted signal, and an acquisition unit that acquires the identification code based on an output of the directional coupler. In this case, the identification code represented by the plurality of signal components can be acquired from the transmitted signal.

[0041] (25) In the above (22) or (23), the identification device may include a determination unit that outputs a determination result regarding the identification based on the power of the transmitted signal. In this case, the determination result regarding the identification based on the identification code can be output without acquiring multiple signal components representing the identification code from the transmitted signal.

[0042] (26) An identification device according to a fifth aspect of the present disclosure includes a circuit that identifies a wire harness having an electric wire, the wire including a passive element unit including a plurality of open stubs with a unique combination or arrangement of electrical lengths and disposed between a first end and a second end, based on an identification signal obtained from the electric wire, The identification signal is either a reflected signal obtained at the first end when a predetermined signal is input from the first end, or a transmitted signal obtained at the second end when the predetermined signal is input from the first end.

[0043] (27) A wire harness according to a sixth aspect of the present disclosure includes an electric wire and a passive element portion provided between a first end and a second end of the electric wire. The passive element portion includes a plurality of open stubs. A combination of electrical lengths of the plurality of open stubs or an arrangement of the plurality of open stubs is unique.

[0044] [Details of Embodiments of the Present Disclosure] Specific examples of an identification system, an identification device, or a wire harness according to embodiments of the present disclosure will be described below with reference to the drawings. Note that in the following embodiments, identical components are assigned the same reference numerals. Their functions and names are also identical. Therefore, detailed description thereof will not be repeated.

[0045] (First embodiment) [Overall configuration] Referring to Fig. 1 , an identification system 50 according to this embodiment is a system for identifying a connected wire harness 80, and includes the wire harness 80 and an identification device 100 for identifying the wire harness 80. The wire harness 80 connects communication between devices. The identification system 50 is mounted on, for example, a vehicle 40. The vehicle 40 is equipped with various on-vehicle devices including a first on-vehicle device 60 and a second on-vehicle device 70. The wire harness 80 connects communication between, for example, the first on-vehicle device 60 and the second on-vehicle device 70.

[0046] The wire harness 80 includes an electric wire portion 82, a first connector 84 connected to a first end of the electric wire portion 82, and a second connector 86 connected to a second end of the electric wire portion 82. The electric wire portion 82 includes one or more electric wires (also referred to as "transmission lines") that transmit signals. The wire harness 80 is provided with a reflecting portion 90 that reflects signals traveling through the transmission lines (electric wires). The reflecting portion 90 includes a plurality (N: N is an integer greater than or equal to 2) of open stub filters (hereinafter simply referred to as "open stubs"). The plurality of open stubs are configured so that a reflected signal includes an identification code for identifying the wire harness 80. Therefore, the reflecting portion 90, which is formed by the plurality of open stubs, functions as an identifier for identifying the wire harness 80. Details of the reflecting portion 90 will be described later.

[0047] The identification device 100 is mounted on, for example, a first in-vehicle device 60. In addition to the identification device 100, the first in-vehicle device 60 includes a first communication unit 62, a first control unit 64, a first electrical board 66, and a connector 68. The first control unit 64 controls the first communication unit 62 and the identification device 100. The first communication unit 62, the first control unit 64, and the identification device 100 are mounted on the first electrical board 66. The connector 68 is provided on the first electrical board 66 and is connected to, for example, a first connector 84 of the wire harness 80.

[0048] The second in-vehicle device 70 includes a second communication unit 72, a second control unit 74, a second electrical board 76, and a connector 78. The second control unit 74 controls the second communication unit 72. The second communication unit 72 and the second control unit 74 are mounted on the second electrical board 76. The connector 78 is provided on the second electrical board 76 and is connected to, for example, a second connector 86 of the wire harness 80.

[0049] The identification device 100 transmits a predetermined signal toward the reflector 90 of the wire harness 80 and identifies the wire harness 80 based on the reflected wave of the signal. In the present embodiment, the identification device 100 obtains an identification code for identifying the wire harness 80. The identification device 100 may be configured to be mounted on the second in-vehicle device 70 instead of the first in-vehicle device 60, or may be configured to be mounted on both the first in-vehicle device 60 and the second in-vehicle device 70.

[0050] 2, the first in-vehicle device 60 includes a first communication unit 62, the identification device 100, and a first control unit 64 that controls these. When the first in-vehicle device 60 is an ECU, the first communication unit 62 includes a PHY (PHYsical layer). The PHY is configured by a chip mounted on the ECU that transmits and receives signals.

[0051] The first control unit 64 includes a CPU (Central Processing Unit) 640 and a storage unit 642. The storage unit 642 stores software (computer programs) executed by the CPU 640 and various information (data). The storage unit 642 includes an identification information storage unit 644 that stores identification information for identifying a wire harness. The identification information includes, for example, product information such as the model number and type of the wire harness. The identification information storage unit 644 stores, for example, the product information of the wire harness and an identification code for identifying the wire harness in association with each other.

[0052] The CPU 640 of the first control unit 64 determines the type of the connected wire harness 80 based on the identification code acquired by the identification device 100 and the information stored in the identification information storage unit 644. For example, the CPU 640 of the first control unit 64 determines whether the connected wire harness 80 is a genuine wire harness. This makes it possible to determine whether the connected wire harness is genuine or not.

[0053] When the first control unit 64 detects that a legitimate wire harness is not connected to the first in-vehicle device 60 (that an unauthorized wire harness is connected), it executes a predetermined process, such as halting (blocking) communication by the first communication unit 62. This prevents communication with unintended devices, thereby preventing hacking of the in-vehicle device or data tampering.

[0054] (Identification Device 100) Referring to FIG. 3 , the identification device 100 includes a pulse generating circuit 102 and a reading circuit 110. The pulse generating circuit 102 is a type of signal generating circuit and transmits a predetermined pulse signal to an electric wire (transmission line) on which a reflecting unit 90 is provided. The pulse generating circuit 102 emits a square-wave pulse signal. The driving of the pulse generating circuit 102 is controlled, for example, by the first control unit 64 (see FIG. 2 ), and the pulse generating circuit 102 emits a pulse signal to the reflecting unit 90 at a predetermined timing. Specifically, the pulse generating circuit 102 emits a pulse signal to the reflecting unit 90, for example, when the ignition of the vehicle is turned on, when the identification system 50 is started, or at a predetermined time. Note that the timing at which the pulse generating circuit 102 emits the pulse signal may be other than these. Furthermore, the signal transmitted by the signal generating circuit to the electric wire may be a signal other than a pulse signal (for example, a step signal).

[0055] The electric wires of the genuine wire harness 80 are provided with the reflecting section 90 described above. The reflecting section 90 includes a plurality of open stubs 92. The pulse signal emitted by the pulse generating circuit 102 is reflected by the reflecting section 90, and the reflected wave is input to the reading circuit 110. The reading circuit 110 reads the identification code from the reflected wave. The reading circuit 110 includes a directional coupler 112 that extracts the reflected wave (reflected signal) reflected by the reflecting section 90, a wave detector 114 that detects the reflected wave from the directional coupler 112, and a shift register 116 that latches the reflected wave from the wave detector 114 to extract the identification code from the reflected signal.

[0056] More specifically, the directional coupler 112 extracts a reflected wave (reflected signal) from the reflected wave reflected by the reflector 90, the reflected wave corresponding to the characteristics of the open stub 92 that constitutes the reflector 90. The detector 114 is electrically connected to one end of the directional coupler 112, and extracts a signal wave from the reflected wave extracted by the directional coupler 112. The shift register 116 is connected to the end of the detector 114 opposite to the directional coupler 112 (an end different from the end to which the directional coupler is connected), and latches the reflected wave (reflected signal) from the detector 114 to extract the identification code contained in the reflected signal.

[0057] 4, the second in-vehicle device 70 includes a second communication unit 72 and a second control unit 74 that controls the second communication unit 72. When the second in-vehicle device 70 is an ECU, the second communication unit 72 includes a PHY. The PHY is configured by a chip mounted on the ECU that transmits and receives signals.

[0058] The second control unit 74 includes a CPU 740 and a storage unit 742. The storage unit 742 stores software (computer programs) executed by the CPU 740 and various information (data).

[0059] (Open Stub) The characteristics of the open stub will be described with reference to Fig. 5. The open stub 42 is a narrow-band filter provided on the transmission line (electrical wire 44) and has a predetermined electrical length. The open stub 42 is a band reject filter that exhibits short-circuit characteristics at a specific frequency (resonant frequency f). In other words, the open stub 42 is a filter that blocks frequency components in a band including the resonant frequency f and passes other frequency components.

[0060] The resonant frequency f is controlled by the electrical length of the open stub 42, and the bandwidth and depth thereof are controlled by the width of the open stub 42. The shape of the open stub 42 is set so that the resonant frequency f is located within a predetermined band.

[0061] The open stub 42 has a function of reflecting a signal. The identification system 50 utilizes the function of reflecting a signal that the open stub has in order to identify the wire harness.

[0062] [System Configuration] The configuration of the identification system 50 according to this embodiment will be described in more detail with reference to FIGS.

[0063] Referring to FIG. 6 , the identification system 50 includes the wire harness 80 and the identification device 100, as described above. The wire harness 80 includes an electric wire 88 (transmission line), a reflecting portion 90 provided on the electric wire 88, and a first connector 84. The electric wire 88 of the wire harness 80 is connected to the identification device 100 by connecting the first connector 84 to the connector 68 of the first on-board device 60 (see FIG. 1 ). The pulse generating circuit 102 of the identification device 100 is connected to the electric wire 88 via the connector 68 and the first connector 84. A directional coupler 112 is disposed between the pulse generating circuit 102 and the connector 68. The electrical length b of the directional coupler 112 can be set so as to maximize the reflected waveform from the reflecting portion 90. For example, the electrical length b of the directional coupler 112 can be set to the same length as the electrical length of the open stub that constitutes the reflecting portion 90. This configuration maximizes the degree of coupling of the directional coupler 112.

[0064] The configuration of the reflector 90 will be described in more detail with reference to Fig. 7. The reflector 90 is provided at a predetermined position on the electric wire 88 (transmission line). The plurality of open stubs 92 (each open stub will also be referred to as an "open stub 92" unless it is necessary to distinguish between them) that make up the reflector 90 are configured so that the reflected signal contains an identification code for identifying the wire harness 80. The identification code is configured by the combination of the presence or absence of the open stubs 92.

[0065] Specifically, the electric wire 88 provided with the reflecting portion 90 has a plurality (M locations) of positions 500a, 500b, 500c, 500d, 500e, ..., 500m (collectively referred to as "positions 500") where the open stub 92 can be formed according to the identification code. These positions 500 are arranged at equal intervals, separated by a predetermined distance L. The predetermined distance L can be, for example, approximately 3 cm.

[0066] At each position 500, the state in which an open stub 92 is formed is represented by [1], and the state in which an open stub 92 is not formed is represented by [0]. Thus, each position corresponds to one bit of the identifier. For example, consider a case in which open stubs 92a, 92b, 92c, and 92n are formed at positions 500a, 500b, 500e, and 500m, respectively, and no open stubs 92 are formed at positions 500c and 500d. In this case, the multiple open stubs 92 are configured so that their reflected signals include an identification code of [11001...1]. Note that in FIGS. 6 and 7, the state in which an open stub 92 is formed is represented by a solid line, and the state in which an open stub 92 is not formed is represented by a dashed line.

[0067] The identification code is a code of 2 or more bits. For example, the identification code may be an 8-bit code. In this case, the number of the multiple positions 500 is "8", and the number of the multiple open stubs 92 is 2 or more and 7 or less. The number of open stubs 92 and the positions at which the open stubs 92 are formed are determined according to the set identification code.

[0068] The multiple open stubs 92 have the same electrical length a. The number (N) of the multiple open stubs 92 is less than the number (M) of the multiple positions 500. That is, the number (N) of the multiple open stubs 92 and the number (M) of the multiple positions 500 have the relationship 2≦N<M. These multiple open stubs 92 are electrically connected to one of the multiple positions 500. In other words, no open stub 92 is formed at one of the multiple positions 500. Therefore, a code in which all bits are [1] ([11111...1]) and a code in which all bits are [0] ([00000...0]) are not set as identification codes.

[0069] For example, if an unauthorized wire harness without a reflecting portion is connected, a code in which all bits are [0] will be detected because no reflected waves will be detected. Furthermore, if an unauthorized wire harness with electric wires that are not connected to the identification device 100 is connected, a code in which all bits are [1] will be detected because the pulse signal will be reflected. If a code in which all bits are [0] or a code in which all bits are [1] is set as the identification code, it becomes difficult to determine whether the connected wire harness is a legitimate wire harness or an unauthorized wire harness. On the other hand, by excluding in advance from the identification code the code in which all bits are [0] and the code in which all bits are [1], it becomes easier to detect that an unauthorized wire harness has been connected.

[0070] The electric wire 88 on which the reflecting portion 90 is provided may be a dedicated line for identification (an electric wire not used for communication), or may be a communication line used for communication.

[0071] Referring again to FIG. 6 , the pulse generation circuit 102 of the identification device 100 transmits a square-wave pulse signal to the reflection unit 90. The pulse generation circuit 102 includes, for example, a first Schmitt trigger inverter 120, a second Schmitt trigger inverter 122, a resistor 124, and a capacitor 126. The second Schmitt trigger inverter 122 is connected in series with the first Schmitt trigger inverter 120. The resistor 124 is connected in parallel with the first Schmitt trigger inverter 120. The capacitor 126 is connected in series with the first Schmitt trigger inverter 120 on the side of the first Schmitt trigger inverter 120 opposite the second Schmitt trigger inverter 122. The first Schmitt trigger inverter 120, the resistor 124, and the capacitor 126 constitute an oscillation circuit 128. The second Schmitt trigger inverter 122 has the function of shaping the signal waveform from the oscillation circuit 128. The pulse generating circuit 102 generates, for example, one pulse signal and emits it toward the wire harness 80. However, the pulse generating circuit 102 is not limited to this circuit configuration.

[0072] The directional coupler 112 monitors the reflected wave from the wire harness 80 and supplies the reflected wave to the detector 114. The detector 114 includes, for example, a Schottky diode 130 and a low-pass filter 132 connected to the cathode side of the Schottky diode 130. The low-pass filter 132 includes, for example, a coil 134 and a capacitor 136. The reflected wave (reflected signal) from the detector 114 is supplied to a shift register 116 (see FIG. 3 ).

[0073] Referring to FIG. 8, the shift register 116 serially latches the reflected wave (reflected signal) from the detector 114 (see FIG. 6). The shift register 116 includes flip-flops, the number of which corresponds to the number of bits of the identification code. Adjacent flip-flops are connected to each other, and the reflected wave (reflected signal) is serially input to these flip-flops. The clock signal (CLK) has a clock period corresponding to the spacing (distance L: see FIG. 7) between multiple positions where open stubs may be formed (i.e., a clock period corresponding to the period E of the reflected wave). Each flip-flop in the shift register 116 latches the reflected wave (reflected signal) in synchronization with the rising edge of the clock signal. As a result, each flip-flop in the shift register 116 latches the reflected wave and outputs a value of [1], or a value of [0] if there is no reflected wave. In this way, the shift register 116 extracts the identification code contained in the reflected signal. In addition, in FIGS. 6 and 8, the portion of the reflected wave (reflected signal) indicated by the broken line indicates that there is no reflected wave due to the absence of an open stub.

[0074] (Configuration Example of Shift Register) With reference to FIG. 9, a configuration example of the shift register 116a for reading an identification code when the identification code is composed of 8 bits will be described.

[0075] This shift register 116a includes eight flip-flops 140a to 140h (collectively referred to as "flip-flops 140"). The eight flip-flops 140 are connected in series. The reflected signal is input to the leftmost flip-flop 140a, which latches the reflected wave. The output of flip-flop 140a is designated as output Q0. The output Q0 from flip-flop 140a is input to the next flip-flop 140b, which latches the output Q0.

[0076] Similarly, the next flip-flop 140c receives the output Q1 from flip-flop 140b and latches the output Q1. The flip-flop 140d receives the output Q2 from flip-flop 140c and latches the output Q2. The flip-flop 140e receives the output Q3 from flip-flop 140d and latches the output Q3. The flip-flop 140f receives the output Q4 from flip-flop 140e and latches the output Q4. The flip-flop 140g receives the output Q5 from flip-flop 140f and latches the output Q5. The flip-flop 140h receives the output Q6 from the flip-flop 140g and latches the output Q6, and outputs an output Q7.

[0077] FIG. 10 is an example of a timing chart of the shift register 116a shown in FIG. 9. Referring to FIG. 10, the measurement pulse wave is an input signal for generating a reflected wave. Specifically, the measurement pulse wave is a pulse wave generated by the pulse generating circuit 102 (see FIG. 6). The reflected wave corresponds to the reflected signal in FIG. 9. Q[7...0] is the data obtained by latching the reflected wave, i.e., the identification code. In this example, the 8-bit identification code is [11001111].

[0078] As described above, the identification system 50 according to this embodiment includes the wire harness 80 provided with the reflecting unit 90, and the identification device 100 to which the wire harness 80 is connected. The identification device 100 identifies the wire harness 80 based on a reflected signal from the reflecting unit 90. The identification device 100 includes a pulse generating circuit 102 that emits a pulse signal to the reflecting unit 90, and a reading circuit 110 that reads an identification code from the reflected signal based on the wave reflected from the reflecting unit 90. The reflecting unit 90 includes a plurality of open stubs 92 that reflect the pulse signal from the pulse generating circuit 102. The plurality of open stubs 92 are configured so that the reflected signal includes an identification code for identifying the wire harness 80.

[0079] The identification device 100 identifies the connected wire harness by reading the identification code from the reflected signal, thereby determining whether or not a normal wire harness is connected, thereby improving communication security with a simple configuration.

[0080] The reflecting section 90 is configured so that the reflected signal includes an identification code for identifying the wire harness 80 based on the combination of the presence or absence of the open stub 92. This makes it possible to easily generate an identification code for identifying the wire harness.

[0081] The reading circuit 110 includes a directional coupler 112, a detector 114, and a shift register 116. The directional coupler 112 extracts the reflected wave reflected by the reflecting unit 90. The detector 114 is connected to the directional coupler 112 and extracts a reflected signal from the reflected wave. The shift register 116 latches the reflected signal (reflected wave) from the detector 114 to extract the identification code from the reflected signal. By configuring the identification device 100 in this manner, it is possible to read the identification code with a simple circuit configuration. Therefore, a system for reading an identification code (identifier) ​​can be constructed by combining simple circuits without using expensive equipment such as a TDR (Time Domain Reflectometry).

[0082] As described above, the shift register 116 may be configured to serially latch the reflected signals, which makes it easier to read the identification code.

[0083] Second Embodiment The identification system according to this embodiment differs from the first embodiment in that it latches reflected waves in parallel at regular time intervals, whereas the first embodiment latches reflected waves serially. The other configurations are the same as those of the first embodiment.

[0084] 11, an identification system 52 according to the present embodiment includes an identification device 200 instead of identification device 100 (see FIG. 3). Identification device 200 includes a reading circuit 210 instead of reading circuit 110 (see FIG. 3). Reading circuit 210 includes a plurality of registers arranged in parallel (hereinafter, the plurality of registers will be collectively referred to as "registers 216") instead of shift register 116 (see FIG. 3).

[0085] Referring to FIG. 12 , a register 216 latches the reflected wave (reflected signal) from the detector 114 (see FIG. 11 ) in parallel. The register 216 includes flip-flops, the number of which corresponds to the number of bits of the identification code. The reflected wave (reflected signal) is input in parallel to these flip-flops. A clock signal (CLK) is input to each flip-flop in sequence at a time interval (i.e., an interval corresponding to the period E of the reflected wave) corresponding to the distance (distance L) between multiple positions 500 (see FIG. 7 ) where open stubs may be formed. For this reason, delay lines (DL) 218 ​​for delaying the clock signal are provided between adjacent flip-flops. Each delay line 218 is a component that slows down the propagation of an electrical signal and is composed of, for example, a coil (inductance) and a capacitor (capacitance).

[0086] Each flip-flop of register 216 latches the reflected wave (reflected signal) in synchronization with the rising edge of the clock signal. As a result, each flip-flop of register 216 latches the reflected wave and outputs a value of [1], or outputs a value of [0] if there is no reflected wave. In this way, register 216 extracts the identification code contained in the reflected signal. Note that in Figure 12, the portion of the reflected wave (reflected signal) indicated by a dashed line indicates that there is no reflected wave due to the absence of an open stub.

[0087] (Example of shift register configuration) Referring to Figure 13, an example of the configuration of multiple registers (hereinafter, multiple registers will be collectively referred to as "registers 216a") arranged in parallel for reading an identification code when the identification code is composed of 8 bits will be described.

[0088] This register 216a includes eight flip-flops 140a to 140h (collectively referred to as "flip-flops 140"). Reflected signals are input in parallel to the eight flip-flops 140. The output of each flip-flop is the opposite of that in the first embodiment. That is, in this embodiment, from the leftmost flip-flop 140a to the rightmost flip-flop 140h, the output is Q7 → Q0.

[0089] 14 is an example of a timing chart of the register 216a. Referring to Fig. 14, the clock signal (CLK) is a single pulse wave that is input to each flip-flop while being delayed by a time D through a delay line (DL). The time D corresponds to an interval according to the period E of the reflected wave (see Fig. 12).

[0090] 13, a clock signal (CLK) is input to the leftmost flip-flop 140a, which latches the reflected wave in synchronization with the rising edge of the clock signal and outputs Q7. A clock signal (CLK_Delay1) delayed by time D is input to the next flip-flop 140b, which latches the reflected wave in synchronization with the rising edge of the clock signal and outputs Q6.

[0091] Similarly, the next flip-flop 140c receives a clock signal (CLK_Delay2) delayed by a further time D, which latches the reflected wave in synchronization with the rising edge of the clock signal and outputs Q5. The next flip-flop 140d receives a clock signal (CLK_Delay3) delayed by a further time D, which latches the reflected wave in synchronization with the rising edge of the clock signal and outputs Q4. The next flip-flop 140e receives a clock signal (CLK_Delay4) delayed by a further time D, which latches the reflected wave in synchronization with the rising edge of the clock signal and outputs Q3. The next flip-flop 140f receives a clock signal (CLK_Delay5) delayed by a further time D, which latches the reflected wave in synchronization with the rising edge of the clock signal and outputs Q2. A clock signal (CLK_Delay6) that is further delayed by time D is input to flip-flop 140g, which latches the reflected wave in synchronization with the rising edge of the clock signal and outputs Q1. A clock signal (CLK_Delay7) that is further delayed by time D is input to flip-flop 140h, which latches the reflected wave in synchronization with the rising edge of the clock signal and outputs Q0.

[0092] 14, each flip-flop latches and outputs the reflected wave in parallel as described above. Q[7...0] is the data obtained by latching the reflected wave, i.e., the identification code. In this example, the 8-bit identification code is [11001111].

[0093] In this way, in the identification system 52 according to this embodiment, the register 216 latches the reflected wave in parallel to extract the identification code. This makes it easier to latch the reflected wave even when the period E of the reflected wave is short (i.e., the frequency is high). This also makes it easier to read the identification code.

[0094] Other effects are the same as those of the first embodiment.

[0095] (Third embodiment) The identification system according to this embodiment differs from the above-described embodiments in that the electrical lengths of the multiple open stubs that make up the reflector are different from one another, and the identification device has a circuit configuration that corresponds to such a reflector.

[0096] 15 , the identification system 54 according to the present embodiment includes a wire harness 600 and an identification device 300. The wire harness 600 includes a reflecting portion 610. The reflecting portion 610 includes a plurality of open stubs 612 (each open stub will also be referred to as an "open stub 612" unless it is necessary to distinguish between them). The wire harness 600 has a configuration similar to that of the wire harness 80 (see FIG. 1 ) according to the first and second embodiments. However, the wire harness 600 according to the present embodiment differs from the above-described embodiments in that the reflecting portion 610 is provided instead of the reflecting portion 90 (see FIG. 1 ).

[0097] The identification device 300 includes a read circuit 310 instead of the read circuit 110 (see FIG. 3) or the read circuit 210 (see FIG. 11). The read circuit 310 includes a directional coupler 312 and a detector 314 instead of the directional coupler 112 (see FIG. 3) and the detector 114 (see FIG. 3), respectively.

[0098] 16 , the multiple open stubs 612 that make up the reflector 610 have different electrical lengths. Because open stubs have spurious resonances, the multiple open stubs 612 in the reflector 610 have electrical lengths that prevent the spurious resonances from overlapping. The multiple open stubs 612 are arranged so that the electrical lengths of the open stubs 612 increase with increasing distance from the directional coupler 312. In other words, the multiple open stubs 612 are arranged in descending order of resonant frequency from the side closest to the directional coupler 312 to the side furthest from the directional coupler 312.

[0099] 17 , the configuration of the reflecting portion 610 will be described in more detail. The electric wire 88 on which the reflecting portion 610 is provided has a plurality (M locations) of positions 500a, 500b, 500c, 500d, 500e, ..., 500m (collectively referred to as "positions 500") at which open stubs 612 can be formed according to the identification code. For example, consider a case where open stubs 612a, 612b, 612c, and 612n are formed at positions 500a, 500b, 500e, and 500m, respectively, and no open stubs 612 are formed at positions 500c and 500d. The open stub 612a at position 500a has an electrical length a1, the open stub 612b at position 500b has an electrical length a2, the open stub 612c at position 500e has an electrical length a3, and the open stub 612n at position 500m has an electrical length a4. The relationship between the electrical lengths of the open stubs 612 is electrical length a1 < electrical length a2 < electrical length a3 < electrical length a4. In this case, for example, the frequency f1 component of the pulse signal is reflected by the open stub 612n, the frequency fn-1 component of the pulse signal is reflected by the open stub 612b, and the frequency fn component of the pulse signal is reflected by the open stub 612a. The resonant frequencies increase in the order of frequency fn > frequency fn-1 > frequency 1. Therefore, by arranging the open stubs 612 reflecting the highest resonant frequencies in a direction away from the directional coupler 312, the mixture of reflections from the open stubs 612 is suppressed. If an open stub is formed at position 500c, the open stub will reflect, for example, the frequency fn-2 component of the pulse signal. Note that the intervals between multiple positions where open stubs 612 can be formed may or may not be equal.

[0100] 16 , the directional coupler 312 includes multiple directional couplers (couplers) 312a to 312m having different electrical lengths. The number of the multiple directional couplers is, for example, the same as the number of positions (M positions) at which the open stub 612 can be formed. That is, the directional coupler 312 includes the same number of directional couplers (couplers) as the number of bits in the identification code. The multiple directional couplers 312a, 312b, ..., 312m correspond to the open stubs 612 that can be formed at multiple positions 500a, 500b, ..., 500m, respectively. Specifically, when the open stub 612 is formed at any of the multiple positions 500a, 500b, ..., 500m, the multiple directional couplers 312a, 312b, ..., 312m have electrical lengths equal to the electrical lengths of any of the open stubs 612. The plurality of directional couplers 312 a , 312 b , . . . , 312 m are arranged such that the electrical length of the directional couplers 312 increases with increasing distance from the reflecting section 610 .

[0101] For example, the electrical length b1 of directional coupler 312a closest to reflector 610 is set to the same length as the electrical length a1 of open stub 612a closest to directional coupler 312, and the electrical length b2 of directional coupler 312b next closest to reflector 610 is set to the same length as the electrical length a2 of open stub 612b next closest to directional coupler 312. The electrical length bm of directional coupler 312m farthest from reflector 610 is set to the same length as the electrical length a4 of open stub 612n farthest from directional coupler 312. As a result, the reflected wave of frequency fn from open stub 612a is extracted by directional coupler 312a, the reflected wave of frequency fn-1 from open stub 612b is extracted by directional coupler 312b, and the reflected wave of frequency f1 from open stub 612n is extracted by directional coupler 312m.

[0102] If no open stub is formed at any of the multiple positions 500, the electrical length of the directional coupler 312 corresponding to that position is set to the same as the electrical length of the open stub that would be set if an open stub were formed at that position.

[0103] A plurality of detectors 314 are provided corresponding to the plurality of directional couplers 312. That is, the detectors 314 include a plurality of detectors 314a, 314b, ..., 314m (collectively referred to as "detectors 314") that are connected one-to-one to each of the plurality of directional couplers 312. The output from each of the detectors 314a, 314b, ..., 314m corresponds to each bit of the identification code. Each detector 314 has a configuration similar to that of the detector 114 in the first embodiment (see FIG. 6).

[0104] 16 and 17, the state in which the open stub 612 is formed is indicated by a solid line, and the state in which the open stub 612 is not formed is indicated by a dashed line. Furthermore, the electric wire 88 on which the reflecting portion 610 is provided may be a dedicated line for identification (an electric wire not used for communication) or may be a communication line used for communication.

[0105] As described above, in the identification system 54 according to this embodiment, the plurality of open stubs 612 are electrically connected to any of the plurality of positions 500 so that the electrical length of the open stubs 612 increases with increasing distance from the directional coupler 312. This makes it possible to prevent reflections from the open stubs from mixing together, thereby reducing the output of the pulse signal transmitted from the pulse generating circuit 102. As a result, the power used when transmitting the pulse signal can be used effectively.

[0106] The directional coupler 312 includes a plurality of directional couplers 312a, 312b, ..., 312m having different electrical lengths. When an open stub 612 is formed at any of the plurality of positions 500, each of the plurality of directional couplers 312a, 312b, ..., 312m has an electrical length equal to the electrical length of one of the open stubs 612. The plurality of directional couplers 312a, 312b, ..., 312m are arranged such that the electrical length of the directional coupler 312 increases with increasing distance from the reflecting portion 610. This makes it easier to extract a reflected signal from the reflection of each open stub 612.

[0107] A plurality of detectors 314 are provided corresponding to a plurality of directional couplers 312. This allows the identification code to be identified in the frequency axis direction, making it easier to read the identification code. Note that in the first and second embodiments, the identification code is identified in the time axis direction.

[0108] (Fourth Embodiment) The identification system according to this embodiment differs from the third embodiment in that the electrical lengths of the open stubs constituting the reflector are set based on the pulse signal generated by the pulse generation circuit. Specifically, the multiple open stubs are formed so that the electrical lengths of the open stubs are odd multiples of a quarter wavelength of the fundamental wave of the pulse signal transmitted by the pulse generation circuit. The remaining configuration is the same as that of the third embodiment.

[0109] 18 , an identification system 56 according to the present embodiment includes a wire harness 700 and an identification device 400. The wire harness 700 includes a reflecting portion 710. The reflecting portion 710 includes a plurality of open stubs 712. The wire harness 700 has a configuration similar to that of the wire harness 80 (see FIG. 1 ) according to the first and second embodiments. However, the wire harness 700 according to the present embodiment differs from the above-described embodiments in that the reflecting portion 710 is provided instead of the reflecting portion 90 (see FIG. 1 ).

[0110] The identification device 400 includes a read circuit 410 instead of the read circuit 310 (see FIG. 15). The read circuit 410 includes a directional coupler 412 instead of the directional coupler 312 (see FIG. 15).

[0111] 19, the square wave pulse signal generated by the pulse generating circuit 102 is a combination of a fundamental wave and a harmonic wave. Therefore, the frequency components of the pulse signal are expressed by the following equation (1).

[0112] Here, V is the peak value.

[0113] The pulse width T of the pulse signal is given by the following equation (2).

[0114]

[0115] The frequency of the pulse signal may be the same as the fundamental wave (sinx) or an odd multiple of the fundamental wave (sin3x, sin5x, . . . ).

[0116] The multiple open stubs 712 (each open stub will also be referred to as an "open stub 712" unless it is necessary to distinguish between them) that make up the reflector 710 have different electrical lengths. Specifically, as described above, the multiple open stubs 712 are formed so that their electrical lengths are a quarter wavelength of the fundamental wave (sin x) and a quarter wavelength of an odd multiple of the fundamental wave.

[0117] 20 , an electric wire 88 provided with a reflecting portion 710 has a plurality (M locations) of positions 500a, 500b, 500c, 500d, 500e, ..., 500m at which open stubs 712 can be formed according to an identification code. As in the above-described embodiment, consider a case in which open stubs 712a, 712b, 712c, and 712n are formed at positions 500a, 500b, 500e, and 500m, respectively, and no open stubs 712 are formed at positions 500c and 500d. The open stub 712a at position 500a has an electrical length c1, the open stub 712b at position 500b has an electrical length c2, the open stub 712c at position 500e has an electrical length c3, and the open stub 712n at position 500m has an electrical length c4. The electrical lengths of the open stubs 712 are related as follows: electrical length c1 < electrical length c2 < electrical length c3 < electrical length c4. Furthermore, the electrical length of each open stub 712 is set to ¼ wavelength of the fundamental wave (sin x) and ¼ wavelength of an odd-numbered multiple of the fundamental wave. The electrical length of one of the multiple open stubs 712 may be the same as the fundamental wave (sin x). In this case, for example, the frequency f component of the pulse signal is reflected by open stub 712 n, the frequency (2n-3)f component of the pulse signal (frequency component that is (2n-3) times f: n is an integer greater than or equal to 2) is reflected by open stub 712 b, and the frequency (2n-1)f component of the pulse signal (frequency component that is (2n-1) times f) is reflected by open stub 712 a. If an open stub is formed at position 500 c, for example, the frequency (2n-5)f component of the pulse signal is reflected by that open stub.

[0118] 19 , the directional coupler 412 includes a plurality of directional couplers (couplers) 412a, 412b, ..., 412m having different electrical lengths. The electrical lengths of these directional couplers 412 correspond to the electrical length of the open stub 712. In this respect, the directional coupler 412 differs from that of the third embodiment. The other configurations of the directional coupler 412 are the same as those of the third embodiment.

[0119] 19 and 20, the state in which the open stub 712 is formed is indicated by a solid line, and the state in which the open stub 712 is not formed is indicated by a dashed line. Furthermore, the electric wire 88 on which the reflecting portion 710 is provided may be a dedicated line for identification (an electric wire not used for communication) or may be a communication line used for communication.

[0120] As described above, in the identification system 56 according to this embodiment, the multiple open stubs 712 are formed so that the electrical lengths of the open stubs are ¼ wavelength of the fundamental wave and ¼ wavelength of an odd multiple of the fundamental wave of the pulse signal transmitted by the pulse generating circuit 102. This makes it easy to prevent reflections from the open stubs 712 from mixing together, and therefore makes it easy to reduce the output of the pulse signal transmitted from the pulse generating circuit 102. As a result, power can be used more effectively when transmitting the pulse signal.

[0121] The other configurations and effects are the same as those of the third embodiment.

[0122] Fifth Embodiment Referring to FIG. 21 , a wire harness 800 according to the present embodiment is a harness using a flat cable 810, and includes electric wires 812, a sheet-like holding member 820 that holds the electric wires 812, a first connector 84, and a second connector 86.

[0123] The sheet-like holding member 820 is made of, for example, an insulating resin material (resin sheet). The electric wires 812 include a first electric wire 814 for identification and a second electric wire 816 for communication. The first electric wire 814 for communication is a dedicated transmission line not used for communication. The second electric wire 816 for communication is a communication line that connects communication between devices. Both the first electric wire 814 and the second electric wire 816 are wired to extend along the longitudinal direction of the holding member 820. Note that the electric wires 812 may be configured to include electric wires other than the first electric wire 814 and the second electric wire 816.

[0124] The first connector 84 is connected to a first end of the electric wire 812, and the second connector 86 is connected to a second end of the electric wire 812. The first electric wire 814 for identification is electrically connected to at least one of the first connector 84 and the second connector 86. For example, when the first connector 84 is connected to the above-mentioned identification device, the first electric wire 814 for identification is connected to at least the first connector 84. When the second connector 86 is connected to the above-mentioned identification device, the first electric wire 814 for identification is connected to at least the second connector 86.

[0125] The wire harness 800 further includes a reflecting portion 830, similar to the reflecting portion shown in the above embodiment, provided on the first electric wire 814 for identification. The reflecting portion 830 includes a plurality of open stubs, similar to the above embodiment. The plurality of open stubs are, for example, individually connected to the first electric wire 814 to form the reflecting portion 830.

[0126] As a wire harness using a flat cable, an assembly harness such as e-STEALTH (registered trademark) is known. The wire harness 800 according to the present embodiment can also be configured using such an assembly harness.

[0127] According to this embodiment, it is possible to obtain a flat wire harness 800 that can improve communication security with a simpler configuration.

[0128] The other configurations and effects are the same as those of the first to third embodiments.

[0129] 22 , a wire harness 850 according to the present embodiment differs from the fifth embodiment in that a reflecting portion 860 is formed by a member separate from the electric wires. The other configurations are the same as those of the fifth embodiment.

[0130] The wire harness 850 includes a flat cable 852 as an electric wire portion. The flat cable 852 includes a first electric wire 870 for identification purposes that is not used for communication, and a second electric wire 872 for communication purposes. A reflecting portion 860 (reflective member) is connected to the first electric wire 870 for identification purposes. The reflecting portion 860 includes a plurality of open stubs 862 and a connection portion 864 to which the plurality of open stubs 862 are connected. The reflecting portion 860 is formed by processing a flat member such as a metal plate or a metal foil, so that the plurality of open stubs 862 and the connection portion 864 are integrally formed. The plurality of open stubs 862 are each integrally formed with the connection portion 864 so as to intersect with the connection portion 864 at a predetermined angle (e.g., 90 degrees). For example, the reflecting portion 860 is formed by processing a copper plate or copper foil, etc., using a punching process, laser processing, or the like. The reflecting portion 860 is disposed on the first electric wire 870 such that the connecting portion 864 is along the first electric wire 870. The reflecting portion 860 may be fixed to the first electric wire 870 by, for example, spot welding or the like.

[0131] The flat cable 852 includes a base film 874 on which the first electric wire 870, the reflecting portion 860, and the second electric wire 872 are arranged, and a cover film 876 that covers the first electric wire 870, the reflecting portion 860, and the second electric wire 872. The base film 874 and the cover film 876 are made of flexible insulating films (sheets).

[0132] The flat cable 852 may be configured to further include other electric wires in addition to the first electric wire 870 and the second electric wire 872. Furthermore, the number of layers in which the electric wires are arranged is not limited to one, and a configuration in which multiple layers are stacked is also possible.

[0133] Note that connectors are not shown in Fig. 22. As shown in the fifth embodiment, the wire harness 850 has a first connector 84 (see Fig. 21) and a second connector 86 (see Fig. 21) provided at the ends of a flat cable 852.

[0134] (Method of manufacturing wire harness 850) First, the base film 874, the cover film 876, the first electric wire 870, the second electric wire 872, the reflective portion 860, the first connector, and the second connector are prepared. As for the reflective portion 860, as described above, the reflective portion 860 is formed by processing a copper plate, copper foil, or the like.

[0135] 23 , the first connector 84 is attached to a first end in the longitudinal direction of the base film 874, and the second connector 86 is attached to a second end in the longitudinal direction. Next, the first electric wire 870 and the second electric wire 872 are placed on the base film 874. One end of the first electric wire 870 and the second electric wire 872 are each electrically connected to a predetermined channel of the first connector 84, and the other end of the first electric wire 870 and the second electric wire 872 are each electrically connected to a predetermined channel of the second connector 86.

[0136] 24 , a reflecting portion 860 (a reflecting member) is placed at a predetermined position on a first electric wire 870, and a connecting portion 864 is fixed to the first electric wire 870 by spot welding. For example, the connecting portion 864 is fixed to the first electric wire 870 by spot welding at three locations, ie, positions 860a, 860b, and 860c.

[0137] 25, cover film 876 is attached to base film 874 so as to cover first electric wire 870, reflecting portion 860, and second electric wire 872. In this manner, wire harness 850 according to the present embodiment is obtained.

[0138] 26 , in the reflecting portion 860, the connecting portion 864 has a plurality of positions 500a, 500b, 500c, 500d, 500e, ..., 500m where a plurality of open stubs 862 (each open stub will be referred to as an "open stub 862" unless it is necessary to distinguish between them) can be formed. However, by providing the reflecting portion 860 to the first electric wire 870, it can be said that the first electric wire 870 also has a plurality of positions 500a, 500b, 500c, 500d, 500e, ..., 500m. Although FIG. 26 illustrates a configuration in which the plurality of open stubs 862 have the same electrical length, this embodiment is not limited to such a configuration. The plurality of open stubs 862 may have different electrical lengths, as shown in the third and fourth embodiments.

[0139] In the wire harness 850 of the present embodiment, as described above, the reflecting portion 860 is configured by a member separate from the first electric wire 870. The reflecting portion 860 is provided along the first electric wire 870 and includes the connection portion 864 connected to the first electric wire 870, and a plurality of open stubs 862 provided integrally with the connection portion 864. This makes it possible to easily provide the reflecting portion 860 in the wire harness 850.

[0140] The other configurations and effects are the same as those of the above-described embodiment.

[0141] Seventh Embodiment A wire harness according to this embodiment differs from the sixth embodiment in that a reflective portion is formed by patterning a conductive layer provided on an insulating film by etching. The other configurations are the same as those of the sixth embodiment.

[0142] Referring to FIG. 27 , a reflective portion 880 is formed on a base film 874a constituting a flat cable. The reflective portion 880 includes a plurality of open stubs 882 (each open stub will also be referred to as an "open stub 882" unless it is necessary to distinguish between them) and a connection portion 884 to which the plurality of open stubs 882 are connected. The base film 874a is a film member having a conductive layer formed on one side, such as a flexible substrate, and the reflective portion 880 is formed by etching the conductive layer (not shown) on the base film 874a into the shape of the reflective portion. The reflective portion may also be a copper foil sticker having an adhesive layer on one side formed in the shape of the reflective portion. In this case, the sticker-like reflective portion may be attached to the base film 874a, for example.

[0143] 28 , a first connector 84 is attached to a first end of a base film 874a in the longitudinal direction, and a second connector 86 is attached to a second end of the base film 874a in the longitudinal direction. Next, a first electric wire 870 and a second electric wire 872 are arranged on the base film 874a. The first electric wire 870 is arranged so as to be located above a connecting portion 884 of the reflecting portion 880, thereby electrically connecting the reflecting portion 880 to the first electric wire 870. Thereafter, a cover film is attached to the base film 874a.

[0144] In the wire harness 890 of this embodiment, the reflecting portion 880 can also be easily provided on the wire harness 890. Other configurations and effects are similar to those of the above-described embodiment.

[0145] (Eighth embodiment) Referring to Figure 29, the identification device 900 of this embodiment differs from the above-mentioned embodiments in that it is not implemented in an on-board device, but is used outside the vehicle exclusively to identify the type of wire harness 1000.

[0146] Similar to the above-described embodiment, the wire harness 1000 includes an electric wire portion 1010 and a connector 1020 connected to an end of the electric wire portion 1010. The wire harness 1000 is provided with a reflecting portion 1030 similar to the above-described reflecting portion.

[0147] The identification device 900 includes a connector 902 to which a connector 1020 of the wire harness 1000 is connected.

[0148] 30, an identification device 900 includes a pulse generating circuit 910, a reading circuit 920, a control circuit 930, a display unit 940, and an operation unit 950. The pulse generating circuit 910 and the reading circuit 920 have the same configurations as the pulse generating circuit and the reading circuit shown in the above embodiment.

[0149] The operation unit 950 accepts operations by a user. The control circuit 930 controls the pulse generating circuit 910 and the display by the display unit 940 in response to instructions from the operation unit 950. The control circuit 930 includes a CPU 932 and a storage unit 934. The storage unit 934 stores software (computer programs) executed by the CPU 932 and various information (data). The storage unit 934 includes an identification information storage unit 936 that stores identification information for identifying a wire harness. The identification information includes, for example, product information such as the model number and type of the wire harness. The identification information storage unit 936 stores, for example, product information of the wire harness and an identification code for identifying the wire harness in association with each other.

[0150] The CPU 932 determines the type and other information of the connected wire harness 1000 based on the identification code from the reading circuit 920 and the information stored in the identification information storage unit 936. The CPU 932 displays the determination result on the display unit 940. The display unit 940 displays product information and other information of the wire harness 1000 connected to the identification device 900.

[0151] As described above, the identification device 900 according to the present embodiment can easily identify the type of the wire harness 1000, thereby facilitating management of the wire harness 1000. For example, it is possible to effectively prevent the wire harness from being attached incorrectly.

[0152] Ninth Embodiment Fig. 31 is a diagram showing an identification system 1050 according to a ninth embodiment. Fig. 32 is a block diagram of the identification system 1050 according to the ninth embodiment. The identification system 1050 of this embodiment differs from the above-described embodiments in that it identifies a wire harness based on a transmitted signal that has passed through the electric wires of the wire harness. The identification system 1050 of this embodiment includes a wire harness 1080 and an identification device 1100 that identifies the wire harness 1080. The configuration other than the identification system 1050 is the same as that of the first embodiment.

[0153] The wire harness 1080 of this embodiment has a passive element portion 1090 instead of a reflector portion. The electric wire portion 82, the first connector 84, and the second connector 86 of the wire harness 1080 have the same configuration as those of the above-described embodiments. The passive element portion 1090 has the same configuration as the reflector portion 90. The passive element portion 1090 includes a plurality of open stubs. The plurality of open stubs are configured so that an identification code for identifying the wire harness 1080 is included in the transmitted signal. Therefore, the passive element portion 1090 formed by the plurality of open stubs functions as an identifier for identifying the wire harness 1080. Details of the passive element portion 1090 will be described later.

[0154] The identification device 1100 provides a predetermined signal to the wire harness 1080. When the predetermined signal is provided to the wire harness 1080, the identification device 1100 identifies the wire harness 1080 based on a transmitted signal obtained from the wire harness 1080. In other words, the transmitted signal is an identification signal. The identification device 1100 may be configured to be mounted in the second in-vehicle device 70 instead of the first in-vehicle device 60, or may be configured to be mounted in both the first in-vehicle device 60 and the second in-vehicle device 70.

[0155] As shown in FIG. 32 , the identification device 1100 has a pulse generating circuit 102 and a reading circuit 1110. The configuration of the pulse generating circuit 102 is as described above. That is, the pulse generating circuit 102 has the function of providing a predetermined signal to the wire harness 1080. The reading circuit 1110 has a directional coupler 1112 and a detector 1114. The directional coupler 1112 has the function of extracting multiple signal components contained in the predetermined signal. The detector 1114 detects the output of the directional coupler 1112 and outputs an identification code. That is, the detector 1114 functions as an acquisition unit that acquires the identification code based on the output of the directional coupler 1112.

[0156] The wire harness 1080 has an electric wire 1088 in addition to the passive element portion 1090. The electric wire 1088 has a first end 1088a and a second end 1088b. The passive element portion 1090 is provided between the first end 1088a and the second end 1088b. The first end 1088a is connected to the pulse generating circuit 102. The second end 1088b is connected to the directional coupler 1112. The pulse generating circuit 102 inputs a predetermined signal from the first end 1088a. The directional coupler 1112 extracts multiple signal components from a transmitted signal obtained from the second end 1088b when the predetermined signal is input.

[0157] Fig. 33 is a diagram showing details of the identification system 1050 of Fig. 32. In Fig. 33, the passive element section 1090 of the wire harness 1080 includes a plurality of open stubs 1092. The plurality of open stubs 1092 have different electrical lengths. The combination of the electrical lengths of the plurality of open stubs 1092 is unique. Therefore, the transmitted signal includes an identification code based on the combination of the electrical lengths of the plurality of open stubs 1092.

[0158] The combination of electrical lengths of the plurality of open stubs 1092 includes a plurality of electrical lengths corresponding to some of the plurality of signal components contained in the predetermined signal. The predetermined signal generated by the pulse generating circuit 102 is a square wave, and includes a fundamental wave component and harmonic components having frequencies that are odd multiples of the fundamental wave frequency, as shown in the above-mentioned formula (1).

[0159] That is, the plurality of signal components contained in the predetermined signal having a fundamental frequency f include a frequency f component, a frequency 3f component, a frequency 5f component, a frequency 7f component, and so on. Here, the plurality of signal components contained in the predetermined signal are assumed to be a frequency f component (fundamental wave component), a frequency 3f component, a frequency 5f component, a frequency 7f component, a frequency 9f component, and a frequency 11f component. Of these signal components, a portion of the plurality of open stubs 1092 is assumed to be a frequency f component, a frequency 3f component, a frequency 7f component, a frequency 9f component, and a frequency 11f component. That is, the plurality of signal components contained in the predetermined signal are the six signal components described above, and a portion of these six signal components is assumed to be five signal components excluding the frequency 5f component. In this case, the plurality of open stubs 1092 includes five open stubs 1092 corresponding to the five frequency components, as shown in FIG. 33 .

[0160] 34 is a diagram showing a passive element section 1090 of the ninth embodiment. As described above, the passive element section 1090 of this embodiment has five open stubs 1092a, 1092b, 1092c, 1092e, and 1092f. The five open stubs 1092 of this embodiment have the same configuration as those of the other embodiments described above. Therefore, the five open stubs 1092 may be provided integrally with the wire harness 1080, or may be provided separately from the electric wires 1088.

[0161] The open stub 1092a, which has the shortest electrical length d1, corresponds to the 11f frequency component. The open stub 1092b, which has electrical length d2, corresponds to the 9f frequency component. The open stub 1092c, which has electrical length d3, corresponds to the 7f frequency component. The open stub 1092e, which has electrical length d4, corresponds to the 3f frequency component. The open stub 1092f, which has electrical length d5, corresponds to the f frequency component.

[0162] Although the open stubs 1092 in this embodiment are arranged in order of shortest electrical length from the pulse generating circuit 102 side, the multiple open stubs 1092 do not have to be arranged in order of length. Furthermore, the intervals between adjacent pairs of open stubs 1092 do not have to be the same, and they may be arranged at unequal intervals.

[0163] The five open stubs 1092 in this embodiment have electrical lengths that are ¼ of the wavelengths of some of the multiple signal components corresponding to the multiple open stubs 1092. Therefore, electrical length d1 is ¼ of the wavelength of the frequency 11f component. Electrical length d2 is ¼ of the wavelength of the frequency 9f component. Electrical length d3 is ¼ of the wavelength of the frequency 7f component. Electrical length d4 is ¼ of the wavelength of the frequency 3f component. Electrical length d5 ​​is ¼ of the wavelength of the frequency f component.

[0164] In other words, the resonant frequencies of the five open stubs 1092a are the frequencies of the corresponding signal components. The five open stubs 1092a function as band-elimination filters that eliminate the corresponding signal components. Therefore, when a predetermined signal (square wave) from the pulse generating circuit 102 is applied to the electric wire 1088, the transmitted signal obtained at the second end 1088b is a signal obtained by eliminating the frequency f component, frequency 3f component, frequency 7f component, frequency 9f component, and frequency 11f component from the signal components contained in the predetermined signal.

[0165] 33 , the identification device 1100 includes the above-described pulse generating circuit 102 and a reading circuit 1110. The identification device 1100 also includes a first line 1116, a second line 1118, and a termination circuit 1120. The first line 1116 is a line connecting the pulse generating circuit 102 and a first end 1088a of the electric wire 1088. The end of the first line 1116 on the electric wire 1088 side is connected to the first end 1088a via the connector 68 and the first connector 84. The pulse generating circuit 102 provides a predetermined signal to the first end 1088a via the first line 1116.

[0166] The second line 1118 is a line connected to the second end 1088b of the electric wire 1088. The end of the second line 1118 on the electric wire 1088 side is connected to the second end 1088b via the connector 68 and the first connector 84. A termination circuit 1120 is connected to the end of the second line 1118 opposite the electric wire 1088 side. The termination circuit 1120 terminates the end of the second line 1118 opposite the electric wire 1088 side. The transmitted signal obtained at the second end 1088b is guided to the identification device 1100 by the second line 1118.

[0167] The directional coupler 1112 of the reading circuit 1110 is provided on the second line 1118. The directional coupler 1112 is provided between the second connector 86 and the termination circuit 1120. The directional coupler 1112 has a plurality of couplers corresponding to a plurality of signal components included in the predetermined signal. In this embodiment, the plurality of signal components included in the predetermined signal is six, and therefore the directional coupler 1112 has six couplers 1112a, 1112b, ... 1112f. Note that in FIG. 33 , only couplers 1112a, 1112b, and 1112f are shown, and the others are omitted.

[0168] The electrical length bf of the coupler 1112f is the same as the electrical length d5 ​​of the open stub 1092f. The electrical length b2 of the coupler 1112b is the same as the electrical length d2 of the open stub 1092b. The electrical length b1 of the coupler 1112a is the same as the electrical length d1 of the open stub 1092a. In this way, the electrical length of each of the six couplers 1112a, 1112b... 1112f is ¼ of the wavelength of the six signal components contained in the specified signal. Therefore, the directional coupler 1112 can extract six signal components from the transmitted signal.

[0169] The output of the directional coupler 1112 is provided to the detector 1114. The detector 1114 includes a plurality of detectors 1114a, 1114b, ..., 1114f corresponding to the six directional couplers 1112a, 1112b, ..., 1112f. The output of the detector 1114 is the identification code contained in the transmitted signal. In this way, the detector 1114 constitutes an acquisition unit that acquires the identification code based on the output of the directional coupler 1112.

[0170] The transmitted signal of this embodiment is a signal from which the frequency f component, frequency 3f component, frequency 7f component, frequency 9f component, and frequency 11f component have been removed from the signal components contained in the predetermined signal. Therefore, the output of the directional coupler 1112 includes only the output corresponding to the frequency 5f component. Therefore, if the outputs of the directional coupler 1112 are arranged in descending order of frequency to create an identification code, the identification code of the wire harness 1080 of this embodiment would be [000100], as shown in FIG.

[0171] In this embodiment, the identification code is determined by the combination of the electrical lengths of the multiple open stubs 1092. In this embodiment, the multiple signal components included in the predetermined signal are the six signal components described above. The combination of electrical lengths of the open stubs 1092 is selected from six electrical lengths corresponding to the frequencies of the six signal components. The open stubs 1092 remove the signal components corresponding to the electrical lengths of the open stubs 1092 from the predetermined signal. As a result, the transmitted signal includes an identification code indicating the combination of the electrical lengths of the multiple open stubs 1092. Each value of the identification code is determined by the presence or absence of each of the six signal components. Therefore, the identification code in this embodiment is six bits long. As described above, the identification code values ​​are arranged in order of increasing frequency of the corresponding signal component.

[0172] In the identification code of this embodiment, of the six signal components, those signal components that do not have a corresponding open stub 1092 are set to "1," and those signal components that have a corresponding open stub 1092 are set to "0." Note that the identification code can be inverted by providing an inverting amplifier or the like after each detector 1114a, 1114b, ..., 1114f and inverting the output of each detector 1114a, 1114b, ..., 1114f.

[0173] In this embodiment, the identification code is determined by a combination of open stubs 1092 with electrical lengths corresponding to six signal components contained in a predetermined signal. The passive element section 1090 in this embodiment has five open stubs 1092 with electrical lengths corresponding to the five signal components other than the 5f frequency component. Therefore, the transmitted signal in this embodiment includes the above-mentioned identification code.

[0174] When a normal wire harness is connected, the above-mentioned identification code is obtained. On the other hand, when an abnormal wire harness is connected, the above-mentioned identification code is not obtained. Furthermore, in a wire harness different from the wire harness 1080 of this embodiment, the combination of electrical lengths of the open stubs 1092 may be different. In this case, the correct identification code may not be obtained. The identification device 1100 can determine whether a normal wire harness is connected based on whether the correct identification code is obtained.

[0175] The identification system 1050 of this embodiment includes a wire harness 1080 including an electric wire 1088 and a passive element portion 1090 provided between a first end 1088a and a second end 1088b of the electric wire 1088, and an identification device 1100 that identifies the wire harness 1080 based on an identification signal obtained from the electric wire 1088. The identification signal is a transmitted signal obtained at the second end 1088b when a predetermined signal is input from the first end 1088a. The passive element portion 1090 includes a plurality of open stubs 1092.

[0176] Because the passive element section 1090 configured as described above includes multiple open stubs 1092, the transmitted signal, which is an identification signal, is affected by the combination of the electrical lengths of the multiple open stubs 1092. Because the combination of the electrical lengths of the multiple open stubs 1092 is unique, the effect on the transmitted signal is also unique. Therefore, the transmitted signal can be used to identify the connected wire harness. This makes it possible to determine whether a normal wire harness is connected, thereby improving communication security with a simple configuration.

[0177] Furthermore, the transmitted signal of this embodiment includes an identification code based on the combination of the electrical lengths of the plurality of open stubs 1092. The unique combination of the electrical lengths of the plurality of open stubs 1092 serves as the identification code.

[0178] In this embodiment, the combination of electrical lengths of the plurality of open stubs 1092 includes a plurality of electrical lengths corresponding to some of the plurality of signal components contained in the predetermined signal, thereby allowing the identification code to be represented by the plurality of signal components in the transmitted signal.

[0179] Furthermore, in this embodiment, the predetermined signal includes a square wave, the plurality of signal components include a fundamental wave component of the predetermined signal and harmonic components having frequencies that are odd multiples of the fundamental wave frequency, the electrical lengths of the plurality of open stubs 1092 are ¼ wavelengths of some of the plurality of signal components that correspond to the plurality of open stubs 1092, and the identification device 1100 is configured to obtain the transmitted signal from a position on the second end 1088b side of the passive element unit 1090 in the electric wire 1088. This allows the identification device 1100 to obtain the identification code from the transmitted signal.

[0180] Furthermore, the identification device 1100 is equipped with a directional coupler 1112 that can extract the multiple signal components from the transmitted signal, and a detector 1114 (acquisition unit) that acquires an identification code based on the output of the directional coupler 1112, so that the identification code represented by the multiple signal components can be acquired from the transmitted signal.

[0181] In this embodiment, the passive element portion 1090 includes an identification code in the transmitted signal, but the passive element portion 1090 may include an identification code in the reflected signal. That is, the passive element portion 1090 has the same configuration and function as the reflector portion in the first to eighth embodiments. Furthermore, the wire harness 1080 of this embodiment may have the same configuration as the wire harness in the fifth to eighth embodiments.

[0182] Tenth Embodiment Fig. 35 is a block diagram of an identification system 1050 according to a tenth embodiment. Fig. 36 is a diagram showing details of the identification system 1050 of Fig. 35. This embodiment differs from the ninth embodiment in that an identification device 1100 does not have a directional coupler but has a window comparator 1124, and in that multiple open stubs 1092 are provided on an electric wire 1088 by directional coupling sections.

[0183] The identification device 1100 of this embodiment identifies the wire harness 1080 based on the power of the transmitted signal. The reading circuit 1110 of the identification device 1100 has a detector 1122 and a window comparator 1124. The transmitted signal obtained at the second end 1088b is provided to the detector 1122 of the identification device 1100 by the second line 1118, and then provided to the window comparator 1124.

[0184] The window comparator 1124 determines whether the power of the transmitted signal is within a preset power range. If the power of the transmitted signal is within the power range, the window comparator 1124 outputs a determination result indicating that a normal wire harness 1080 is connected. If the power of the transmitted signal is not within the power range, the window comparator 1124 outputs a determination result indicating that a normal wire harness 1080 is not connected.

[0185] The power of the signal obtained by removing a signal component selected from the six signal components described above from the signal components contained in a predetermined signal differs for each combination of the removed signal components. Therefore, the combination of the electrical lengths of the multiple open stubs 1092 can be determined based on the power of the transmitted signal.

[0186] The power range set in window comparator 1124 is set to include the power of a signal obtained by removing the frequency f component, frequency 3f component, frequency 7f component, frequency 9f component, and frequency 11f component from the signal components contained in a predetermined signal. Furthermore, the power range set in window comparator 1124 is set to a range that does not include the power of any signal other than the signal obtained by removing these five signal components. This allows window comparator 1124 to determine the combination of electrical lengths of multiple open stubs 1092.

[0187] In this way, the window comparator 1124 of this embodiment functions as a determination unit that outputs a determination result regarding identification based on the power of the transmitted signal, thereby making it possible to output a determination result regarding identification based on the identification code without obtaining multiple signal components representing the identification code from the transmitted signal.

[0188] Furthermore, as described above, the multiple open stubs 1092 of this embodiment are not physically connected to the electric wire 1088 as in other embodiments, but are provided on the electric wire 1088 by directional coupling sections. Fig. 37 is a partial enlarged view of the passive element section 1090. Fig. 37 shows an enlarged view of the open stub 1092c included in the passive element section 1090. Here, the open stub 1092c will be described, but the other open stubs 1092 have a similar configuration. Therefore, a description of the configuration of the other open stubs 1092 will be omitted.

[0189] 37 , the open stub 1092c includes a stub body 1200 and a directional coupling portion 1202. The directional coupling portion 1202 is disposed along the electric wire 1088 with a predetermined gap g therebetween. The longitudinal electrical length d10 of the directional coupling portion 1202 is ¼ of the wavelength of the signal component corresponding to the open stub 1092c. Because the open stub 1092c corresponds to the 7f frequency component, the electrical length d10 is ¼ of the wavelength of the 7f frequency component. As a result, the directional coupling portion 1202 couples with the electric wire 1088, and only the 7f frequency component of the predetermined signal (square wave) propagating through the electric wire 1088 is obtained from the end portion 1202a.

[0190] A first end 1200a of the stub body 1200 is connected to the end 1202a. A second end 1200b of the stub body 1200 is an open end. The electrical length d3 of the stub body 1200 in the longitudinal direction is ¼ of the wavelength of the 7f frequency component. Therefore, the stub body 1200 functions as an open stub.

[0191] According to this configuration, by coupling the directional coupling portion to the electric wire 1088, multiple open stubs 1092 can be made to function, making it easy to configure the passive element portion 1090 and the wire harness 1080 as separate entities.

[0192] Furthermore, by adjusting the gap g, the filter characteristics of the multiple open stubs 1092 can be adjusted, thereby increasing the degree of freedom in designing the multiple open stubs 1092. Fig. 38A is a diagram illustrating a portion of the frequency characteristics of a transmitted signal in the tenth embodiment. As shown in Fig. 38A, the frequency f component, frequency 3f component, and frequency 7f component of the transmitted signal are removed by the multiple open stubs 1092. On the other hand, the frequency 5f component, for which no corresponding open stub 1092 is provided, is not removed.

[0193] 38B is a diagram showing another example of a portion of the frequency characteristics of a transmitted signal in the tenth embodiment. In the example of FIG. 38B, the gap g of the directional coupling unit 1202 is set wider than the gap g in the example of FIG. 38A. Comparing FIG. 38A and FIG. 38B, the amount of power removed is smaller in FIG. 38B, but the bandwidth removed is narrower. As a result, the intervals between the removed bands are wider, making it easier to determine whether the signal components have been removed by the multiple open stubs 1092.

[0194] For example, in the ninth embodiment, to narrow the bandwidth that is removed in the frequency characteristics of the transmitted signal as shown in Fig. 38B, it is necessary to reduce the width of the open stub 1092. However, reducing the width of the open stub 1092 may be limited by physical issues, etc., and it may be difficult to obtain the required characteristics.

[0195] In this regard, in this embodiment, the filter characteristics of the plurality of open stubs 1092 can be adjusted by adjusting the gap g, thereby increasing the degree of freedom in designing the plurality of open stubs 1092.

[0196] The reading circuit 1110 of this embodiment can also be used in the ninth embodiment. Moreover, the reading circuit of the ninth embodiment can be used in place of the reading circuit 1110 of this embodiment.

[0197] In the above embodiment, an example in which the identification device is mounted on an in-vehicle device that performs communication with an ECU or the like is shown. However, the present disclosure is not limited to such an embodiment. For example, the identification device may be configured to be provided in the vehicle separately from the in-vehicle device that performs communication.

[0198] In the first or second embodiment, the electrical lengths of the plurality of open stubs may be configured so that some of them have different lengths.

[0199] In the third or fourth embodiment, the electrical lengths of the plurality of open stubs may be configured so that some of them have the same length.

[0200] In the above embodiment, the power received by the directional coupler may be transmitted as well as reflected. In this case, the frequency components reflected by the multiple open stubs are not included in the transmitted waveform, so the inverted information of the code indicated by the identifier is read.

[0201] Embodiments obtained by appropriately combining the techniques disclosed above are also included within the technical scope of the present disclosure.

[0202] The embodiments disclosed herein are merely examples, and the present disclosure is not limited to the above-described embodiments. The scope of the present disclosure is defined by the claims in the scope of the claims, taking into consideration the description of the detailed description of the invention, and includes all modifications within the meaning and scope equivalent to the wording described therein.

[0203] 40 Vehicle 42 Open stub 44 Electric wire 50, 52, 54, 56 Identification system 60 First on-board device 62 First communication unit 64 First control unit 66 First electrical board 68 Connector 70 Second on-board device 72 Second communication unit 74 Second control unit 76 Second electrical board 78 Connector 80 Wire harness 82 Electric wire unit 84 First connector 86 Second connector 88 Electric wire 90 Reflection unit 92, 92a, 92b, 92c, 92n Open stub 100 Identification device 102 Pulse generation circuit 110 Reading circuit 112 Directional coupler 114 Detector 116, 116a Shift register 120 First Schmitt trigger inverter 122 Second Schmitt trigger inverter 124 Resistor 126 Capacitor 128 Oscillator circuit 130 Schottky diode 132 Low-pass filter 134 Coil 136 Capacitors 140, 140a, 140b, 140c, 140d, 140e, 140f, 140g, 140h Flip-flop 200 Identification device 210 Read circuit 216, 216a Register 218 Delay line 300 Identification device 310 Read circuit 312, 312a, 312b, 312m Directional coupler 314, 314a, 314b Detector 400 Identification device 410 Read circuit 412 Directional coupler 500, 500a, 500b, 500c, 500d, 500e, 500m Position 600 Wire harness 610 Reflecting portion 612, 612a, 612b, 612c, 612n Open stub 640 CPU 642 Storage portion 644 Identification information storage portion 700 Wire harness 710 Reflecting portion 712, 712a, 712b, 712c, 712n Open stub 740 CPU 742 Storage portion 800 Wire harness 810 Flat cable 812 Electric wire 814 First electric wire 816 Second electric wire 820 Holding member 830 Reflecting portion 850 Wire harness 852 Flat cable 860 Reflecting portion 860a, 860b, 860c Position 862 Open stub 864 Connection portion 870 First electric wire 872 Second electric wire 874 Base film 874a Base film 876 Cover film 880 Reflector 882 Open stub 884 Connection 890 Wire harness900 Identification device 902 Connector 910 Pulse generating circuit 920 Reading circuit 930 Control circuit 932 CPU 934 Memory unit 936 Identification information memory unit 940 Display unit 950 Operation unit 1000 Wire harness 1010 Electric wire unit 1020 Connector 1030 Reflection unit 1050 Identification system 1080 Wire harness 1088 Electric wire 1088a First end 1088b Second end 1090 Passive element unit 1092, 1092a, 1092b, 1092c, 1092e, 1092f, 1092f Open stub 1100 Identification device 1110 Reading circuit 1112, 1112a, 1112b, 1112f Directional coupler 1114, 1114a, 1114b Detector 1116 First line 1118 Second line 1120 Termination circuit 1122 Detector 1124 Window comparator 1200 Stub body 1200a First end 1200b Second end 1202 Directional coupling section 1202a End

Claims

1. An identification system comprising: a wire harness including electric wires and a reflecting portion that reflects a signal flowing through the electric wires; and an identification device connected to the wire harness and identifying the wire harness based on a reflected signal from the reflecting portion, wherein the reflecting portion includes a plurality of open stubs, the reflected signal includes an identification code corresponding to the plurality of open stubs, the identification code is a code that identifies the wire harness; and the identification system comprises: a signal generating circuit that transmits the signal to the electric wires; and a reading circuit that reads the identification code from the reflected signal based on a wave reflected from the reflecting portion.

2. The identification system according to claim 1, wherein the reflecting section is configured so that the reflected signal contains an identification code for identifying the wire harness based on a combination of the presence or absence of the open stub.

3. An identification system as described in claim 1 or claim 2, wherein the reading circuit includes: a directional coupler that extracts the reflected wave reflected by the reflecting portion; and a detector that detects the reflected wave from the directional coupler.

4. The identification system of claim 3, wherein the electric wire has a plurality of positions, the plurality of positions are capable of electrically connecting the open stubs according to the identification code and are arranged at equal intervals on the electric wire, the number of the plurality of open stubs is less than the number of the plurality of positions, the plurality of open stubs have equal electrical lengths and are electrically connected to any of the plurality of positions, and the reading circuit further includes a register that extracts the identification code from the reflected signal by latching the reflected wave from the detector.

5. The identification system of claim 4, wherein the register serially latches the reflected waves.

6. The identification system of claim 4, wherein the register latches the reflected waves in parallel.

7. The identification system of claim 3, wherein the electric wire has a plurality of positions, the plurality of positions are capable of electrically connecting the open stub according to the identification code, the number of the plurality of open stubs is less than the number of the plurality of positions, and the plurality of open stubs are electrically connected to any of the plurality of positions such that the electrical length of the open stub increases with increasing distance from the directional coupler.

8. The identification system according to claim 7, wherein the directional coupler includes a plurality of couplers having different electrical lengths, wherein when the open stub is formed at any of the plurality of positions, the plurality of couplers have an electrical length equal to the electrical length of one of the open stubs, and wherein the plurality of couplers are further arranged such that the electrical lengths of the couplers increase with increasing distance from the reflecting portion.

9. The identification system according to claim 8, wherein a plurality of said detectors are provided corresponding to the plurality of couplers.

10. An identification system according to any one of claims 7 to 9, wherein the plurality of open stubs are formed so that the electrical length of each open stub is 1 / 4 wavelength of the fundamental wave of the signal transmitted by the signal generating circuit and 1 / 4 wavelength of an odd multiple of the fundamental wave.

11. An identification system according to any one of claims 1 to 10, wherein the reflecting portion is a separate member from the electric wire, and includes a connection portion provided along the electric wire and connected to the electric wire, and the plurality of open stubs provided integrally with the connection portion.

12. An identification device for identifying a wire harness, comprising: a signal generating circuit connected to the wire harness and transmitting a predetermined signal to the electric wires of the wire harness; and a reading circuit reading an identification code for identifying the wire harness from a reflected signal based on a wave of the signal reflected from the wire harness.

13. A wire harness comprising: electric wires; and a reflecting portion that reflects a signal flowing through the electric wires, the reflecting portion including a plurality of open stubs configured so that a reflected signal from the reflecting portion includes an identification code for identifying the wire harness.

14. A wire harness as set forth in claim 13, wherein the reflective portion is a member separate from the electric wires, and includes a connection portion provided along the electric wires and connected to the electric wires, and the plurality of open stubs provided integrally with the connection portion.

15. A wire harness according to claim 13 or 14, further comprising: a first electric wire not used for communication; and a second electric wire used for communication.

16. The wire harness according to any one of claims 13 to 15, further comprising a sheet-like holding member that holds the electric wires.

17. An identification system comprising: an electric wire; a wire harness including a passive element unit provided between a first end and a second end of the electric wire; and an identification device that identifies the wire harness based on an identification signal obtained from the electric wire, wherein the identification signal is either a reflected signal obtained at the first end when a predetermined signal is input from the first end, or a transmitted signal obtained at the second end when the predetermined signal is input from the first end, and the passive element unit includes a plurality of open stubs, and the combination of electrical lengths of the plurality of open stubs or the arrangement of the plurality of open stubs is unique.

18. The identification system according to claim 17, wherein the reflected signal and the transmitted signal include an identification code based on a combination of electrical lengths of the plurality of open stubs or an arrangement of the plurality of open stubs.

19. An identification system according to claim 17 or claim 18, wherein the combinations of electrical lengths of the plurality of open stubs include a plurality of electrical lengths corresponding to some of the plurality of signal components contained in the predetermined signal.

20. The identification system according to claim 18, wherein the identification device comprises: a directional coupler capable of extracting multiple signal components contained in the predetermined signal from the identification signal; and an acquisition unit that acquires the identification code based on the output of the directional coupler.

21. The identification system according to claim 20, wherein the directional coupler is capable of extracting the plurality of signal components from the reflected signal.

22. The identification system described in claim 18, wherein the combination of electrical lengths of the plurality of open stubs includes a plurality of electrical lengths corresponding to a portion of a plurality of signal components among a plurality of signal components contained in the predetermined signal, the predetermined signal includes a square wave, the plurality of signal components include a fundamental wave component of the predetermined signal and harmonic components having frequencies that are odd multiples of the fundamental wave frequency, the electrical lengths of the plurality of open stubs are 1 / 4 wavelength of the portion of a plurality of signal components corresponding to the plurality of open stubs, and the identification device obtains the transmitted signal from a position on the electric wire closer to the second end than the passive element portion.

23. The identification system according to claim 22, wherein each of the plurality of open stubs has a stub body and a directional coupling section that connects the electric wire and the stub body, and the directional coupling section extracts a signal component corresponding to each of the plurality of open stubs.

24. An identification system according to claim 22 or claim 23, wherein the identification device comprises: a directional coupler capable of extracting the plurality of signal components from the transmitted signal; and an acquisition unit that acquires the identification code based on the output of the directional coupler.

25. The identification system according to claim 22 or 23, wherein the identification device includes a determination unit that outputs a determination result regarding the identification based on the power of the transmitted signal.

26. An identification device including a circuit for identifying a wire harness having electric wires, the electric wires having a passive element unit including a plurality of open stubs with a unique combination or arrangement of electrical lengths, arranged between a first end and a second end, based on an identification signal obtained from the electric wires, wherein the identification signal is either a reflected signal obtained at the first end when a predetermined signal is input from the first end, or a transmitted signal obtained at the second end when the predetermined signal is input from the first end.

27. A wire harness comprising: an electric wire; and a passive element portion provided between a first end and a second end of the electric wire; wherein the passive element portion includes a plurality of open stubs; and wherein the combination of electrical lengths of the plurality of open stubs or the arrangement of the plurality of open stubs is unique.

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