Security system

Abstract

A security system is a system for connecting communication between a first communication unit and a second communication unit through a communication line. The security system includes: a signal deformation unit that deforms a signal waveform of a communication signal transmitted during communication; and a signal correction unit that corrects the signal waveform deformed by the signal deformation unit.

Description

Technical Field

[0001] This disclosure relates to safety systems, wiring harnesses, connectors, and vehicle-mounted devices.

[0002] This application claims priority based on Japanese Application No. 2023-105866, filed on June 28, 2023, and incorporates all the contents of the aforementioned Japanese application. Background Technology

[0003] Vehicles are equipped with various onboard devices. These devices include various ECUs (Electronic Control Units) that manage functions necessary for the vehicle, such as steering and braking. These ECUs are interconnected to form a network. The ECUs communicate with each other through this network to perform basic vehicle functions such as "driving," "turning," and "stopping." Wiring harnesses are typically used to connect the onboard devices.

[0004] In such vehicle-mounted devices, there is a need for technology to prevent intrusion or data tampering into the device (ECU). Patent Document 1, described later, proposes a connector system for preventing communication between the wiring harness and unwanted devices.

[0005] Patent Document 1 describes a connector system comprising a first connector and a second connector connected thereto. The second connector includes a processing unit that performs manufacturing verification information and sends it to the first connector. The first connector includes a verification unit that verifies the second connector based on verification information received from the second connector. If the verification unit cannot receive verification information, it determines that the verification has failed. The first connector further includes: a switch that, when connected to the second connector, toggles whether to electrically connect the transmission lines within the first connector to the transmission lines within the second connector; and a control unit that controls the switch based on the verification result from the verification unit.

[0006] If the second connector is an invalid connector, the verification unit of the first connector determines that the verification has failed. The control unit of the first connector keeps the switch in the open state. As a result, the electrical connection between the transmission lines of the first and second connectors is severed. Since communication between the wiring harness and unwanted devices can be prevented, the security of communication between devices can be ensured.

[0007] Existing technical documents

[0008] Patent documents

[0009] Patent Document 1: International Publication No. 2019 / 187349 Summary of the Invention

[0010] The security system disclosed herein is used for a system that connects a first communication unit and a second communication unit via a communication line, wherein the security system includes: a signal deformation unit that deforms the signal waveform of a communication signal transmitted in the communication; and a signal correction unit that corrects the signal waveform deformed by the signal deformation unit.

[0011] This disclosure can be implemented not only as a safety system, wiring harness, connector, or vehicle device that includes such a characteristic structure, but also as other systems or devices that include a safety system, wiring harness, connector, or vehicle device. Attached Figure Description

[0012] Figure 1 This is a diagram used to illustrate the safety system of the first embodiment.

[0013] Figure 2 This is a diagram illustrating an example of a signal filtering section (low-pass filter).

[0014] Figure 3 This is a diagram illustrating an example of the frequency characteristics of a low-pass filter.

[0015] Figure 4 This is a diagram illustrating an example of a signal filtering section (open-circuit stub filter).

[0016] Figure 5 This is a diagram illustrating an example of the frequency characteristics of an open-circuit stub filter.

[0017] Figure 6 It is used for explanation Figure 1 The diagram shows the changes in the signal waveform of the communication signal in the security system.

[0018] Figure 7 It means Figure 1 The diagram shows an example of the structure of a safety system.

[0019] Figure 8 It means Figure 7 A diagram showing an example of the structure of a connector for a wire harness.

[0020] Figure 9 This is a diagram illustrating an example of the signal waveform of a received signal under overcorrected conditions.

[0021] Figure 10 This is a diagram illustrating an example of the signal waveform of a received signal under insufficient correction.

[0022] Figure 11 This is a diagram showing an example of the structure of the wire harness according to the second embodiment.

[0023] Figure 12 This is a diagram used to illustrate the safety system of the third embodiment.

[0024] Figure 13 It is used for explanation Figure 12 The diagram shows the changes in the signal waveform of the communication signal in the security system.

[0025] Figure 14 It means Figure 12 The diagram shows an example of the structure of a safety system.

[0026] Figure 15 It means Figure 14 A diagram showing an example of the structure of a connector for a wire harness.

[0027] Figure 16 This is a diagram illustrating an example of the signal waveform of a received signal under insufficient correction.

[0028] Figure 17 This is a diagram illustrating an example of the signal waveform of a received signal under overcorrected conditions.

[0029] Figure 18 This is a diagram illustrating the vehicle-mounted device of the fourth embodiment.

[0030] Figure 19 It means Figure 18 The diagram shows an example of the structure of the vehicle-mounted device.

[0031] Figure 20 This is a diagram illustrating a structural example of a modified vehicle-mounted device.

[0032] Figure 21 This is a diagram illustrating the vehicle-mounted device of the fifth embodiment. Detailed Implementation

[0033] [The problem this disclosure aims to solve]

[0034] The connector system described in Patent Document 1 is an excellent system in terms of ensuring safety. However, the processing unit, verification unit, and control unit are implemented by electronic devices, and the electronic devices and switches are built into the connector, making it difficult to simplify the structure. As a result, manufacturing costs can easily become expensive.

[0035] This disclosure was made to address such problems, and one object of this disclosure is to provide a security system, wiring harness, connector, and vehicle-mounted device that can improve communication security through a simpler structure.

[0036] [The Effects of This Disclosure]

[0037] According to this disclosure, it is possible to provide security systems, wiring harnesses, connectors, and vehicle-mounted devices that can improve communication security through a simpler structure.

[0038] [Description of embodiments of this disclosure]

[0039] Preferred embodiments of this disclosure are described below. At least some of the embodiments described below may also be combined arbitrarily.

[0040] (1) The security system of the first aspect of the present disclosure is used for a system for connecting a first communication unit and a second communication unit through a communication line, wherein the security system includes: a signal deformation unit for deforming the signal waveform of a communication signal transmitted in the communication; and a signal correction unit for correcting the signal waveform deformed by the signal deformation unit.

[0041] The signal deformation section deforms the signal waveform of the communication signal transmitted during communication. The signal correction section corrects the deformed signal waveform. With both the signal deformation section and the signal correction section included, normal communication occurs between the first and second communication units. However, if an unauthorized device is connected to either the first or second communication unit, neither the signal deformation section nor the signal correction section is present. For example, if the signal deformation section is present but the signal correction section is absent, the signal waveform of the communication signal is not corrected. Furthermore, for example, if the signal correction section is present but the signal deformation section is absent, the signal waveform of the communication signal becomes overcorrected. In any case, due to signal quality degradation, normal communication can be suppressed against unauthorized devices. Moreover, the structure of the signal deformation section and the signal correction section is easily simplified. Therefore, according to this security system, communication security can be improved through a simpler structure.

[0042] (2) In (1) above, the signal deformation section may also be configured such that the signal filtering section filters the communication signal, which is a signal within the communication band used for communication, and the signal correction section includes a signal waveform correction circuit that corrects the signal waveform deformed by the signal filtering section. Thus, a simpler structure can be easily achieved.

[0043] (3) In (2) above, the signal filtering unit can also be configured to filter the communication signal transmitted by the first communication unit, and the second communication unit includes a signal waveform correction circuit. This simplifies the installation of the signal waveform correction circuit, making it easy to create a structure that includes a signal waveform correction circuit.

[0044] (4) In (1) above, the signal deformation section may also be configured such that the signal waveform deformation circuit deforms the signal waveform of the communication signal, and the signal correction section includes a signal filtering section that filters the signal waveform deformed by the signal waveform deformation circuit. Thus, a simpler structure can be easily achieved.

[0045] (5) In (4) above, the first communication unit may also be configured such that it includes a signal waveform deformation circuit that deforms the signal waveform of the communication signal transmitted by the first communication unit, and a signal filtering unit is provided on the transmission line up to the second communication unit receiving the communication signal. This simplifies the installation of the signal waveform deformation circuit, making it easy to construct a structure that includes the signal waveform deformation circuit.

[0046] (6) In any of (2) to (5) above, the signal filtering section may also be configured to include a low-pass filter or a band-stop filter. Thus, the signal filtering section can be easily formed.

[0047] (7) In any of (2) to (6) above, the communication between the first communication unit and the second communication unit can also be configured such that the communication between them is connected by a wire harness, the wire harness including a communication line and a connector connected to the end of the communication line, and a signal filtering unit is provided on the communication line or the connector. Thus, a simpler structure can be easily achieved.

[0048] (8) In (7) above, the wire harness may also be configured to include a sheet-like retaining member that holds the communication line. Thus, a flat wire harness that can improve communication security with a simpler structure can be obtained.

[0049] (9) In any of (2) to (6) above, the signal filtering section may be provided on at least one of the first electrical board on which the first communication section is mounted, the connector provided on the first electrical board, the second electrical board on which the second communication section is mounted, and the connector provided on the second electrical board. Thus, a simpler structure can be easily achieved.

[0050] (10) The wiring harness of the second aspect of this disclosure connects the communication between the first communication unit and the second communication unit, wherein the wiring harness includes: a communication line; a connector connected to the end of the communication line; and a signal filtering unit disposed on the communication line or the connector to filter the communication signal transmitted in the communication.

[0051] The signal filtering unit can correct signal waveform distortion when it occurs, and can distort the signal waveform when it is not distorted. For example, when the signal waveform of a transmitted communication signal is distorted, this wiring harness can correct the distortion. Furthermore, for example, if both the first and second communication units have the function of correcting signal waveform distortion, even if the signal waveform is distorted by the signal filtering unit, both units can correct the distortion and receive the communication signal. Therefore, with this structure, communication between the first and second communication units proceeds normally.

[0052] On the other hand, if an unauthorized device is connected to the first or second communication unit, the unauthorized device receives a communication signal distorted by the signal filtering section of the wiring harness. Furthermore, even if the wiring harness is disconnected and an unauthorized device is connected to the first or second communication unit, the unauthorized device will still receive a distorted communication signal due to the distorted signal waveform. Therefore, in such cases, normal communication can be suppressed against unauthorized devices. Thus, by using this wiring harness, communication security can be improved with a simpler structure.

[0053] (11) In (10) above, the signal filtering section may also be configured to include a low-pass filter or a band-stop filter. Thus, the signal filtering section can be easily formed.

[0054] (12) In (10) or (11) above, the wire harness may also be configured to include a sheet-like retaining member that holds the communication line. Thus, a flat wire harness that can improve communication security with a simpler structure can be obtained.

[0055] (13) The connector of the third aspect of this disclosure is used to connect communication between a first communication unit and a second communication unit via a communication line, wherein the connector includes: a housing; and a signal filtering unit disposed within the housing to filter communication signals transmitted in the communication.

[0056] By using this connector, communication security can be improved through a simpler structure.

[0057] (14) The vehicle-mounted device of the fourth aspect of this disclosure communicates with other vehicle-mounted devices via a communication line, wherein the vehicle-mounted device includes a communication unit that communicates with other vehicle-mounted devices, the communication unit includes a signal waveform correction circuit that corrects the distortion of the signal waveform when the signal waveform of the communication signal transmitted from the other vehicle-mounted device is distorted.

[0058] According to this vehicle-mounted device, communication security can be improved through a simpler structure.

[0059] (15) In (14) above, the vehicle-mounted device may also be configured to include a signal filtering unit that filters the signal waveform of the transmitted signal sent to other vehicle-mounted devices to distort the signal waveform. This can further improve communication security.

[0060] (16) The vehicle-mounted device of the fifth aspect of this disclosure communicates with other vehicle-mounted devices via a communication line, wherein the vehicle-mounted device includes a communication unit that communicates with other vehicle-mounted devices, the communication unit including a signal waveform deformation circuit that deforms the signal waveform of a transmitted signal sent to other vehicle-mounted devices.

[0061] According to this vehicle-mounted device, communication security can also be improved through a simpler structure.

[0062] (17) In (16) above, the vehicle-mounted device may also be configured to include a signal filtering unit that filters the signal waveform of a communication signal transmitted from another vehicle-mounted device to correct the waveform distortion. This can further improve communication security.

[0063] [Details of the embodiments of this disclosure]

[0064] Hereinafter, specific examples of safety systems, wiring harnesses, connectors, or vehicle-mounted devices according to embodiments of the present disclosure will be described with reference to the accompanying drawings. Furthermore, in the following embodiments, the same reference numerals are used to denote the same components. Their functions and names are also the same. Therefore, detailed descriptions of them will not be repeated.

[0065] (First Implementation)

[0066] [Overall Structure]

[0067] Reference Figure 1 The safety system 50 of this embodiment is used for a system that connects communication between vehicle-mounted devices (e.g., communication between ECU1 and ECU2) via a communication line 20 (transmission line). The safety system 50 includes: a signal deformation unit 100 that deforms the signal waveform of a communication signal transmitted in communication; and a signal correction unit 120 that corrects the signal waveform deformed by the signal deformation unit 100.

[0068] Furthermore, in this disclosure, "communication band" refers to a frequency band used for communication between devices, such as a band that meets the frequency characteristics of standard specifications such as IEEE 802.3 (registered trademark).

[0069] The signal deformation unit 100 includes a signal filtering unit 102. The signal filtering unit 102 filters the signal within the communication band used for communication, i.e., the aforementioned communication signal.

[0070] The signal filtering unit 102 includes a signal distortion filter 104. That is, in this safety system 50, the signal filtering unit 102 is used as a signal distortion filter 104. The signal distortion filter 104 is provided on the transmission line in the communication between ECU1 and ECU2. The transmitted signals from ECU1 and ECU2 are distorted by the signal distortion filter 104.

[0071] The signal correction unit 120 includes a signal waveform correction circuit 122 for correcting the signal waveform distorted by the signal filtering unit 102 (signal distortion filter 104). The signal waveform correction circuit 122 includes a signal waveform correction circuit 122a disposed in ECU1 and a signal waveform correction circuit 122b disposed in ECU2. The signal waveform correction circuits 122a and 122b are collectively referred to as "signal waveform correction circuit 122". The signal waveform correction circuit 122 may also be configured to be disposed only in either ECU1 or ECU2. Here, an example of distributing the signal waveform correction circuit 122 in both ECU1 and ECU2 will be described.

[0072] ECU1 also includes amplifiers 130 and 132 as input / output buffers. ECU1 transmits a signal (communication signal) to ECU2 via amplifier 130 and receives a signal (communication signal) from ECU2 via amplifier 132. Similarly, ECU2 also includes amplifiers 140 and 142 as input / output buffers. ECU2 transmits a signal (communication signal) to ECU1 via amplifier 140 and receives a signal (communication signal) from ECU1 via amplifier 142.

[0073] In ECU1, the input of the signal waveform correction circuit 122a is connected to the output of amplifier 132. The transmitted signal from ECU2 is input to the signal waveform correction circuit 122a via amplifier 132. The transmitted signal from ECU2 undergoes waveform distortion due to signal distortion filter 104, and the signal waveform correction circuit 122a corrects this distortion. ECU1 receives the corrected communication signal from the signal waveform correction circuit 122a as its received signal.

[0074] The same applies to ECU1. Specifically, in ECU2, the input of the signal waveform correction circuit 122b is connected to the output of amplifier 142. The transmitted signal from ECU1 is input to the signal waveform correction circuit 122b via amplifier 142. The transmitted signal from ECU1 undergoes waveform distortion due to the signal distortion filter 104, and the signal waveform correction circuit 122b corrects this distortion. ECU2 receives the corrected communication signal from the signal waveform correction circuit 122b as its received signal.

[0075] (Signal filtering unit 102)

[0076] The signal filtering unit 102 includes a low-pass filter that functions as a filter with low-pass characteristics or a band-stop filter that functions as a filter with band-stop characteristics. That is, in this embodiment, a low-pass filter or a band-stop filter is used as the signal distortion filter 104.

[0077] Reference Figure 2 The low-pass filter 150 can be configured as a mode filter formed in the transmission line, for example. The mode filter is formed, for example, by setting a portion that reduces the width of the transmission line or setting a portion that increases the width of the transmission line. Figure 3 This is a diagram illustrating an example of the frequency response in a low-pass filter. Figure 3 In the graph, the horizontal axis represents frequency, and the vertical axis represents transmission loss. (See reference...) Figure 3 The low-pass filter attenuates high-frequency power above the cutoff frequency f1.

[0078] Reference Figure 4 The band-stop filter 152 can, for example, be configured as an open-circuit stub filter 154 formed in the transmission line. The open-circuit stub filter 154 is a narrowband filter provided in the transmission line and has an electrical length a. The open-circuit stub filter 154 becomes a band-stop filter that represents short-circuit characteristics at a specific frequency (resonant frequency). Figure 5 This is a diagram illustrating an example of the frequency characteristics of an open-circuit stub filter. Figure 5 In the graph, the horizontal axis represents frequency, and the vertical axis represents transmission loss. (See reference...) Figure 5 The open-circuit stub filter exhibits short-circuit characteristics at the resonant frequency f2, causing power attenuation at that frequency.

[0079] The resonant frequency f2 is determined by the electrical length a of the open-circuit stub filter (refer to...). Figure 4 The bandwidth and depth of the open-circuit stub filter are controlled by the width of the filter. The shape of the open-circuit stub filter is set so that the resonant frequency f2 is located in a predetermined band.

[0080] Thus, the low-pass filter and the band-stop filter cut off high-frequency components. Therefore, due to these filters, the rise and fall of the communication signal are distorted. That is, the cutoff frequency f1 and the resonant frequency f2 are set to a predetermined amount that causes distortion of the communication signal waveform.

[0081] (Signal waveform of communication signal)

[0082] Refer again Figure 1As described above, the security system 50 includes a signal distortion unit 100 (signal distortion filter 104) and a signal correction unit 120 (signal waveform correction circuit 122). The signal waveform of the communication signal distorted in the signal distortion unit 100 is corrected by the signal correction unit 120.

[0083] Figure 6 This is a diagram used to illustrate the changes in signal waveforms in communication signals. Here, we consider the case where ECU2 receives a communication signal sent from ECU1. However, the transmission and reception of signals can also be reversed. Figure 6 In the middle, from top to bottom, are shown the transmitted waveform, the waveform about to be input to the signal distortion filter 104 (reference). Figure 1 The waveform before, by signal distortion filter 104 (refer to) Figure 1 The deformed signal waveform is sent to ECU2 (signal waveform correction circuit 122 (reference)). Figure 1 The input waveform is the waveform before signal correction, and the waveform corrected by the signal waveform correction circuit 122 (see reference). Figure 1 Examples of the corrected signal waveform (received waveform). In each waveform graph, the horizontal axis represents time, and the vertical axis represents voltage (V). The following graphs of the signal waveform follow the same format.

[0084] Reference Figure 6 For example, suppose a communication signal with a rectangular wave waveform is transmitted. This communication signal is attenuated before being input to the signal distortion filter 104, that is, the communication signal before being input to the signal distortion filter 104 becomes a rectangular wave with attenuation. When the attenuated communication signal is input to the signal distortion filter 104, the rise and fall of the signal are distorted due to the signal distortion filter 104. Thus, the signal waveform of the communication signal after passing through the signal distortion filter 104 is deformed. The communication signal with a waveform distorted due to the signal distortion filter 104 is input to the signal waveform correction circuit 122. The waveform of the signal input to the signal waveform correction circuit 122 (input waveform) is deformed and attenuated. The signal waveform correction circuit 122 corrects the deformation (distortion) of the signal waveform caused by the signal distortion filter 104. Therefore, the received waveform becomes an attenuated rectangular wave. That is, a rectangular wave corresponding to the transmitted waveform can be received.

[0085] Thus, in the security system 50, since it includes the signal distortion unit 100 (signal distortion filter 104) and the signal correction unit 120 (signal waveform correction circuit 122), normal communication is possible. When the combination of the signal distortion unit 100 (signal distortion filter 104) and the signal correction unit 120 (signal waveform correction circuit 122) is set to the correct combination (appropriate combination), normal communication is difficult to achieve in other combinations (inappropriate combinations). For example, if either the signal distortion filter 104 or the signal waveform correction circuit 122 is absent, an overcorrected or distorted signal is received.

[0086] [System Architecture]

[0087] Reference Figure 7 The system 40 using the safety system 50 includes a first vehicle-mounted device 60, a second vehicle-mounted device 70, and a wiring harness 80. The wiring harness 80 connects the first vehicle-mounted device 60 and the second vehicle-mounted device 70 for communication. The wiring harness 80 can be a structure that directly connects the first vehicle-mounted device 60 and the second vehicle-mounted device 70, or a structure that indirectly connects the first vehicle-mounted device 60 and the second vehicle-mounted device 70 via other communication lines. When viewed from the first vehicle-mounted device 60, for example, the second vehicle-mounted device 70 may appear as another vehicle-mounted device; conversely, when viewed from the second vehicle-mounted device 70, for example, the first vehicle-mounted device 60 may appear as another vehicle-mounted device.

[0088] The wiring harness 80 includes a communication line 82, a first connector 84 connected to a first end of the communication line 82, and a second connector 86 connected to a second end of the communication line 82. The first connector 84 includes a housing 84a, and the second connector 86 includes a housing 86a.

[0089] The first vehicle-mounted device 60 includes a first communication unit 62, a first electrical board 64 on which the first communication unit 62 is mounted, and a connector 66 disposed on the first electrical board 64. The connector 66 is connected, for example, to a first connector 84 of a wiring harness 80. A communication line 68 (transmission line) is provided on the first electrical board 64 to electrically connect the first communication unit 62 and the connector 66.

[0090] The second vehicle-mounted device 70 includes a second communication unit 72, a second electrical board 74 on which the second communication unit 72 is mounted, and a connector 76 disposed on the second electrical board 74. The connector 76 is connected, for example, to a second connector 86 of a wiring harness 80. A communication line 78 (transmission line) is provided on the second electrical board 74 to electrically connect the second communication unit 72 and the connector 76.

[0091] Both the first vehicle-mounted device 60 and the second vehicle-mounted device 70 are ECUs. In this case, the first communication unit 62 and the second communication unit 72 include a PHY (Physical layer). The PHY is composed of a chip (integrated circuit) installed in the ECU that performs signal transmission and reception. Furthermore, the first vehicle-mounted device 60 can, for example, correspond to the ECU1 described above, and the second vehicle-mounted device 70 can, for example, correspond to the ECU2 described above.

[0092] The first communication unit 62 includes a signal waveform correction circuit 122a. The second communication unit 72 includes a signal waveform correction circuit 122b. A DSP (Digital Signal Processor) circuit for correcting signal waveforms is provided in the communication control ICs respectively provided in the first communication unit 62 and the second communication unit 72. Therefore, the correction circuit (DSP circuit) of the communication control IC in the first communication unit 62 can be used as the signal waveform correction circuit 122a provided in the first vehicle-mounted device 60. Similarly, the correction circuit (DSP circuit) of the communication control IC in the second communication unit 72 can be used as the signal waveform correction circuit 122b provided in the second vehicle-mounted device 70. This facilitates the installation of the signal waveform correction circuit 122a into the first vehicle-mounted device 60 and the signal waveform correction circuit 122b into the second vehicle-mounted device 70.

[0093] Communication between the first communication unit 62 and the second communication unit 72 is achieved via communication line 20. Communication line 20 includes communication line 68, communication line 78, and communication line 82.

[0094] The aforementioned signal filtering unit 102 (signal distortion filter 104) is, for example, provided in the second connector 86 of the wiring harness 80. (See reference...) Figure 8 The second connector 86 includes the aforementioned housing 86a (connector body) and a signal filtering section 102 disposed within the housing 86a. The end of the communication line 82 is located within the housing 86a, and the signal filtering section 102 is disposed, for example, within the communication line 82 within the housing 86a.

[0095] The signal filtering unit 102 includes a low-pass filter or a band-stop filter. In this embodiment, an open-circuit stub filter 154, which is a type of band-stop filter, is provided in the second connector 86. However, the signal filtering unit 102 provided in the second connector 86 is not limited to the open-circuit stub filter 154, and may also be a low-pass filter, for example. Furthermore, the signal filtering unit 102 may be provided in the first connector 84 of the wiring harness 80, or it may be provided in the communication line 82 of the wiring harness 80.

[0096] The correction amount of signal waveform correction circuit 122a is set to appropriately correct the signal waveform distorted by signal distortion filter 104. Similarly, the correction amount of signal waveform correction circuit 122b is also set to appropriately correct the signal waveform distorted by signal distortion filter 104. The correction amounts of signal waveform correction circuits 122a and 122b can be set to a fixed value.

[0097] If an unauthorized device is connected to the first vehicle-mounted device 60 or the second vehicle-mounted device 70, the combination of the signal distortion unit 100 (signal distortion filter 104) and the signal correction unit 120 (signal waveform correction circuit 122) becomes inappropriate. As an example of an inappropriate combination, the absence of the signal distortion unit 100 (signal distortion filter 104) can be cited. In this case, the signal waveform of the received signal (received waveform) is overcorrected by the signal waveform correction circuit 122. Figure 9 This diagram illustrates an example of the received waveform when the signal distortion section 100 (signal distortion filter 104) is absent. (Refer to...) Figure 9 Due to overcorrection, the signal waveform of the communication signal is distorted, and the signal quality deteriorates. Another example of an inappropriate combination is the absence of a signal correction unit 120 (signal waveform correction circuit 122). In this case, the received waveform becomes undercorrected. Figure 10 This diagram illustrates an example of the received waveform when the signal correction unit 120 (signal waveform correction circuit 122) is absent. (Refer to...) Figure 10 Due to insufficient correction, the signal waveform of the communication signal is distorted, and in this case, the signal quality is also degraded.

[0098] More specifically, for example, in order to illegally access the first vehicle-mounted device 60, an unauthorized device is connected to the second connector 86 of the wiring harness 80. In this case, the unauthorized device cannot properly correct the distortion of the signal waveform based on the signal distortion filter 104 (undercorrection), thus suppressing normal communication with the first vehicle-mounted device 60. On the other hand, if the wiring harness 80 is removed and an unauthorized device is connected to the first vehicle-mounted device 60 through another wiring harness, the signal distortion filter 104 is not present. In this case, the signal waveform of the transmitted signal from the unauthorized device becomes overcorrected by the signal waveform correction circuit 122a of the first vehicle-mounted device 60. The first communication unit 62 of the first vehicle-mounted device 60 receives a signal with degraded signal quality from the unauthorized device, thus suppressing communication with the unauthorized device. In other words, in this case, normal communication between the unauthorized device and the first vehicle-mounted device 60 is also suppressed. When the unauthorized device is connected to the second vehicle-mounted device 70, normal communication is suppressed in the same way as described above.

[0099] Thus, in the security system 50 according to this embodiment, the signal deformation unit 100 deforms the signal waveform of the communication signal transmitted during communication. The signal correction unit 120 corrects the deformed signal waveform. With the signal deformation unit 100 and the signal correction unit 120 included, communication between the first communication unit 62 and the second communication unit 72 proceeds normally. On the other hand, if an unauthorized device is connected to the first communication unit 62 or the second communication unit 72, neither the signal deformation unit 100 nor the signal correction unit 120 is present. For example, if the signal deformation unit 100 is present but the signal correction unit 120 is absent, the signal waveform of the communication signal is not corrected (undercorrection). In addition, for example, if the signal deformation unit 100 is absent but the signal correction unit 120 is present, the signal waveform of the communication signal becomes overcorrected. In any case, due to the deterioration of signal quality, normal communication can be suppressed against unauthorized devices. Furthermore, the structure of the signal deformation unit 100 and the signal correction unit 120 can be easily simplified. Therefore, according to this security system 50, communication security can be improved with a simpler structure.

[0100] The signal deformation unit 100 can be configured such that it includes a signal filtering unit 102 that filters the communication signal, which is a signal within the communication band used for communication, and a signal correction unit 120 includes a signal waveform correction circuit 122 that corrects the signal waveform deformed by the signal filtering unit 102. This allows for a simpler structure.

[0101] Furthermore, the signal filtering unit 102 can be configured to filter the communication signal transmitted by the first communication unit 62, and the second communication unit 72 can include a signal waveform correction circuit 122b. Similarly, the signal filtering unit 102 can also be configured to filter the communication signal transmitted by the second communication unit 72, and the first communication unit 62 can include a signal waveform correction circuit 122a. Therefore, there is no need to separately provide a signal waveform correction circuit 122, and it is easy to configure the unit to include a signal waveform correction circuit 122.

[0102] By employing a structure in which the signal filtering section 102 includes a low-pass filter 150 or a band-stop filter 152, the signal filtering section 102 can be easily formed. Such a signal filtering section 102 can be easily installed on the communication line 82 of the wiring harness 80, the first connector 84, or the second connector 86. Therefore, this configuration also allows for a simpler structure.

[0103] (Second Implementation)

[0104] Reference Figure 11The wiring harness 200 in this embodiment is a wiring harness using a flat cable, including a communication line 210, a sheet-shaped retaining member 220 for retaining the communication line 210, a first connector 230, and a second connector 240.

[0105] The sheet-like retaining member 220 is made of, for example, an insulating resin material (resin sheet). The communication line 210 is wired in such a way that it extends along the length of the retaining member 220.

[0106] The first connector 230 is connected to the first end of the communication line 210, and the second connector 240 is connected to the second end of the communication line 210.

[0107] The wiring harness 200 also includes the signal filtering unit 102 mentioned above (see reference 102). Figure 1 The same signal filtering unit 250 is used. The signal filtering unit 250 serves as a signal distortion filter 252. The signal distortion filter 252 includes an open-circuit stub filter 254.

[0108] In this embodiment, the open-circuit stub filter 254 is formed on the communication line 210. The signal distortion filter 252 may also be replaced by, for example, a low-pass filter. The signal filtering unit 250 (signal distortion filter 252) may also be located outside the communication line 210. For example, the signal filtering unit 250 (signal distortion filter 252) may be located on the first connector 230 or the second connector 240 of the wiring harness 200, or it may be located on the communication line 210 of the wiring harness 200.

[0109] Furthermore, as a type of wire harness using flat cables, bundled wire harnesses such as e-STELLTH (registered trademark) are known. The wire harness 200 of this embodiment can also be constructed using such a bundled wire harness.

[0110] According to this embodiment, a flat wire harness 200 that improves communication security through a simpler structure can be obtained. Furthermore, the wire harness 200 of this embodiment can replace the wire harness 200 of the first embodiment (see reference). Figure 4 Alternatively, it can be used with the wiring harness 200 of the first embodiment.

[0111] The other structures are the same as in the first embodiment.

[0112] (Third Implementation)

[0113] [Overall Structure]

[0114] Reference Figure 12 The security system 300 of this embodiment includes a signal deformation unit 160 instead of the signal deformation unit 100 (see reference). Figure 1It includes a signal correction unit 180 instead of the signal correction unit 120 (see reference). Figure 1 ).

[0115] The signal deformation unit 160 includes a signal waveform deformation circuit 162 that deforms the signal waveform of the transmitted signal. The signal waveform deformation circuit 162 includes a signal waveform deformation circuit 162a disposed on ECU1 and a signal waveform deformation circuit 162b disposed on ECU2. The signal waveform deformation circuits 162a and 162b are collectively referred to as "signal waveform deformation circuit 162". The signal waveform deformation circuit 162 may also be configured to be disposed only on either ECU1 or ECU2. Here, an example of disposing of the signal waveform deformation circuit 162 on both ECU1 and ECU2 will be described.

[0116] ECU1 sends a transmission signal (communication signal) to ECU2 via amplifier 130, and receives a transmission signal (communication signal) from ECU2 via amplifier 132. ECU2 sends a transmission signal (communication signal) to ECU1 via amplifier 140, and receives a transmission signal (communication signal) from ECU1 via amplifier 142.

[0117] In ECU1, the output of the signal waveform deformation circuit 162a is connected to the input of the amplifier 130. Therefore, the transmitted signal from ECU1 is sent to ECU2 after its waveform is deformed by the signal waveform deformation circuit 162a.

[0118] The same applies to ECU1 in ECU2. That is, the output of the signal waveform deformation circuit 162b is connected to the input of the amplifier 140. Therefore, the transmitted signal from ECU2 is sent to ECU1 after its waveform is deformed by the signal waveform deformation circuit 162b.

[0119] The signal correction unit 180 includes a signal filtering unit 182. The signal filtering unit 182 filters the signal within the communication band used for communication, namely the aforementioned communication signal.

[0120] In this safety system 300, the signal filtering unit 182 is used as a signal correction filter 184. That is, the signal filtering unit 182 (signal correction unit 180) corrects the signal waveform after it has been deformed by the signal waveform deformation circuit 162 (signal deformation unit 160). The signal correction filter 184 is provided on the transmission line in the communication between ECU1 and ECU2. The signal waveforms of the transmitted signals from ECU1 and ECU2 are corrected by the signal correction filter 184.

[0121] Specifically, the transmitted signal from ECU1 undergoes waveform distortion via signal waveform distortion circuit 162, and then signal waveform correction via signal correction filter 184. ECU2 receives the communication signal corrected by signal correction filter 184 as its received signal. Similarly, the transmitted signal from ECU2 undergoes waveform distortion via signal waveform distortion circuit 162, and then signal waveform correction via signal correction filter 184. ECU1 receives the communication signal corrected by signal correction filter 184 as its received signal.

[0122] (Signal filtering unit 182)

[0123] The signal filtering unit 182 has the same signal filtering unit 182 as in the first embodiment (see reference 182). Figure 1 The same structure applies. That is, the signal filtering unit 182 includes a low-pass filter or a band-stop filter. More specifically, in this embodiment, a low-pass filter or a band-stop filter is used as the signal correction filter 184.

[0124] In this embodiment, the communication signal input to the signal filtering unit 182 is distorted by the signal waveform deformation circuit 162. Therefore, the function of the signal filtering unit 182 in distorting the signal waveform is used as a function to correct the distortion of the signal waveform.

[0125] (Signal waveform of communication signal)

[0126] As described above, the security system 300 includes a signal deformation unit 160 (signal waveform deformation circuit 162) and a signal correction unit 180 (signal correction filter 184). The signal waveform of the communication signal deformed in the signal deformation unit 160 is corrected by the signal correction unit 180.

[0127] Figure 13 This is a diagram used to illustrate the changes in signal waveforms in communication signals. Here, we consider the case where ECU2 receives a communication signal sent from ECU1. However, the transmission and reception of signals can also be reversed. Figure 13 In the middle, from top to bottom, the transmitted waveform and the signal waveform deformation circuit 162 (see reference) are shown in sequence. Figure 12 The deformed signal waveform is about to be input into the signal correction filter 184 (refer to...). Figure 12 The waveform before, by signal correction filter 184 (refer to) Figure 12 Examples of the corrected signal waveform and the received waveform. (Refer to...) Figure 13 For example, suppose a communication signal with a rectangular waveform is transmitted. This communication signal is deformed by a signal waveform deformation circuit 162. The communication signal with the deformed waveform by the signal waveform deformation circuit 162 is attenuated before being input to the signal correction filter 184.

[0128] The signal is attenuated before entering the signal distortion filter 104, meaning the communication signal before entering the signal distortion filter 104 becomes a rectangular wave with attenuation. Therefore, when the attenuated communication signal is input to the signal distortion filter 104, the waveform of the communication signal before entering the signal correction filter 184 becomes a distorted waveform with attenuation. The signal correction filter 184 corrects the distortion of the signal waveform caused by the signal waveform deformation circuit 162. The signal waveform corrected by the signal correction filter 184 becomes an attenuated rectangular wave. Therefore, the received waveform also becomes an attenuated rectangular wave. That is, a rectangular wave corresponding to the transmitted waveform can be received.

[0129] Thus, in the security system 300, since it includes a signal deformation unit 160 (signal waveform deformation circuit 162) and a signal correction unit 180 (signal correction filter 184), normal communication is possible. When the combination of the signal deformation unit 160 (signal waveform deformation circuit 162) and the signal correction unit 180 (signal correction filter 184) is set to the correct combination, normal communication is difficult to achieve with other combinations (illegal combinations). For example, if either the signal waveform deformation circuit 162 or the signal correction filter 184 is absent, an over-corrected or distorted signal may be received.

[0130] [System Architecture]

[0131] Reference Figure 14 The system 40A using the safety system 300 includes a first vehicle-mounted device 60A, a second vehicle-mounted device 70A, and a wiring harness 80A. The wiring harness 80A connects the first vehicle-mounted device 60A and the second vehicle-mounted device 70A for communication. The wiring harness 80A can be a structure that directly connects the first vehicle-mounted device 60A and the second vehicle-mounted device 70A, or it can be a structure that indirectly connects the first vehicle-mounted device 60A and the second vehicle-mounted device 70A via other communication lines. When viewed from the first vehicle-mounted device 60A, for example, the second vehicle-mounted device 70A may appear to be another vehicle-mounted device; conversely, when viewed from the second vehicle-mounted device 70A, for example, the first vehicle-mounted device 60A may appear to be another vehicle-mounted device.

[0132] The wiring harness 80A includes a communication line 82, a first connector 84 connected to a first end of the communication line 82, and a second connector 86 connected to a second end of the communication line 82. The first connector 84 includes a housing 84a, and the second connector 86 includes a housing 86a.

[0133] The first vehicle-mounted device 60A includes a first communication unit 62A, a first electrical board 64 on which the first communication unit 62A is mounted, and a connector 66 disposed on the first electrical board 64. The connector 66 is connected, for example, to a first connector 84 of a wiring harness 80A. A communication line 68 (transmission line) is provided on the first electrical board 64 to electrically connect the first communication unit 62A and the connector 66.

[0134] The second vehicle-mounted device 70A includes a second communication unit 72A, a second electrical board 74 on which the second communication unit 72A is mounted, and a connector 76 disposed on the second electrical board 74. The connector 76 is connected, for example, to a second connector 86 of a wiring harness 80A. A communication line 78 (transmission line) is provided on the second electrical board 74 to electrically connect the second communication unit 72A to the connector 76.

[0135] Both the first vehicle-mounted device 60A and the second vehicle-mounted device 70A are ECUs. In this case, the first communication unit 62A and the second communication unit 72A include PHYs. The PHY is composed of a chip (communication control IC) installed in the ECU that performs signal transmission and reception. Furthermore, the first vehicle-mounted device 60A can, for example, correspond to the ECU1 described above, and the second vehicle-mounted device 70A can, for example, correspond to the ECU2 described above.

[0136] The first communication unit 62A includes a signal waveform deformation circuit 162a. The second communication unit 72A includes a signal waveform deformation circuit 162b. A DSP (Digital Signal Processor) circuit for deforming the signal waveform is provided in the communication control ICs respectively provided in the first communication unit 62A and the second communication unit 72A. Therefore, the deformation circuit (DSP circuit) of the communication control IC in the first communication unit 62A can be used as the signal waveform deformation circuit 162a provided in the first vehicle-mounted device 60A. Similarly, the deformation circuit (DSP circuit) of the communication control IC in the second communication unit 72A can be used as the signal waveform deformation circuit 162b provided in the second vehicle-mounted device 70A. This makes it easier to install the signal waveform deformation circuit 162a into the first vehicle-mounted device 60A and the signal waveform deformation circuit 162b into the second vehicle-mounted device 70A.

[0137] Communication between the first communication unit 62A and the second communication unit 72A is achieved via communication line 20. Communication line 20 includes communication line 68, communication line 78, and communication line 82.

[0138] The aforementioned signal filtering unit 182 (signal correction filter 184) is, for example, provided in the second connector 86 of the wire harness 80A. (See reference...) Figure 15The second connector 86 includes a housing 86a (connector body) and a signal filtering section 182 (signal correction filter 184) disposed within the housing 86a. The end of the communication line 82 is located within the housing 86a, and the signal filtering section 182 is disposed, for example, within the communication line 82 within the housing 86a.

[0139] The signal filtering unit 182 includes a low-pass filter or a band-stop filter. In this embodiment, an open-circuit stub filter 154, which is a type of band-stop filter, is provided in the second connector 86. However, the signal filtering unit 182 provided in the second connector 86 is not limited to the open-circuit stub filter 154, and may also be a low-pass filter, for example. Furthermore, the signal filtering unit 182 may be provided in the first connector 84 of the wire harness 80A, or it may be provided in the communication line 82 of the wire harness 80A.

[0140] The amount of distortion caused by the signal waveform distortion circuit 162 is set to a value that can be appropriately corrected by the signal correction filter 184. Similarly, the amount of distortion of the signal waveform distortion circuit 162 is also set to a value that can be appropriately corrected by the signal correction filter 184. The signal waveform distortion circuit 162 and each distortion amount of the signal waveform distortion circuit 162 can be set to a fixed value.

[0141] If an illegal device is connected to the first vehicle-mounted device 60A or the second vehicle-mounted device 70A, the combination of the signal deformation unit 160 (signal waveform deformation circuit 162) and the signal correction unit 180 (signal correction filter 184) becomes inappropriate. As an example of an inappropriate combination, insufficient correction occurs, for instance, when the signal correction unit 180 (signal correction filter 184) is absent. Figure 16 This diagram shows an example of the received waveform when the signal correction unit 180 (signal correction filter 184) is absent. (Refer to...) Figure 16 Due to insufficient correction, the signal waveform of the communication signal is distorted, and the signal quality deteriorates. As another example of an inappropriate combination, there is overcorrection based on the signal correction filter 184 in the absence of the signal distortion section 160 (signal waveform distortion circuit 162). Figure 17 This diagram illustrates an example of the received waveform when the signal deformation unit 160 (signal waveform deformation circuit 162) is absent. (Refer to...) Figure 17 When the waveform of a communication signal is distorted due to overcorrection, the signal quality deteriorates.

[0142] More specifically, for example, in order to illegally access the first vehicle-mounted device 60A, an unauthorized device is connected to the second connector 86 of the wiring harness 80A. In this case, the unauthorized device is not equipped with the signal waveform distortion circuit 162, so the signal waveform of the signal transmitted from the unauthorized device is overcorrected by the signal correction filter 184. The first communication unit 62A of the first vehicle-mounted device 60A receives a signal with degraded signal quality from the unauthorized device, thus suppressing communication with the unauthorized device. In other words, in this case, normal communication between the unauthorized device and the first vehicle-mounted device 60A is suppressed. On the other hand, when the wiring harness 80A is removed and an unauthorized device is connected to the first vehicle-mounted device 60A through another wiring harness, the signal correction filter 184 is no longer present. In this case, the unauthorized device cannot properly correct the distortion of the signal waveform by the signal waveform distortion circuit 162 (insufficient correction), thus suppressing normal communication with the first vehicle-mounted device 60A. When the unauthorized device is connected to the second vehicle-mounted device 70A, normal communication is also suppressed in the same way as described above.

[0143] Thus, in the security system 300 of this embodiment, communication security can also be improved through a simpler structure.

[0144] The signal deformation unit 160 may include a signal waveform deformation circuit 162 that deforms the signal waveform of the communication signal, and the signal correction unit 180 may include a signal filtering unit 182 that filters the signal waveform deformed by the signal waveform deformation circuit 162. Thus, a simpler structure can be easily achieved.

[0145] Furthermore, the first communication unit 62A includes a signal waveform deformation circuit 162, which can be configured to deform the signal waveform of the communication signal transmitted by the first communication unit 62A. Similarly, the second communication unit 72A includes a signal waveform deformation circuit 162, which can be configured to deform the signal waveform of the communication signal transmitted by the second communication unit 72A. Therefore, the installation of the signal waveform deformation circuit 162 becomes easy, and thus a structure incorporating the signal waveform deformation circuit 162 can be easily achieved. In this case, the signal filtering unit 182 can be configured to be installed on either the transmission line leading to the second communication unit 72A receiving the communication signal from the first communication unit 62A, or on the transmission line leading to the first communication unit 62A receiving the communication signal from the second communication unit 72A.

[0146] The other structures are the same as in the first embodiment.

[0147] Furthermore, in this embodiment, the flat wire harness shown in the second embodiment can also be used.

[0148] (Fourth Implementation)

[0149] In the first embodiment described above, an example is shown where a signal distortion unit (signal distortion filter) is disposed in the wiring harness. However, this disclosure is not limited to such an embodiment. The signal distortion unit may also be a structure disposed in an in-vehicle device, for example.

[0150] Reference Figure 18 An example of an in-vehicle device including a signal deformation section will be described. The in-vehicle device 400 of this embodiment is an ECU. The in-vehicle device 400 has the same structure as the ECU1 or ECU2 in the first embodiment, except that it includes the signal deformation section 410.

[0151] The signal deformation unit 410 has the same characteristics as the signal deformation unit 100 in the first embodiment (see reference). Figure 1 The same structure applies. Specifically, the signal distortion unit 410 includes a signal filtering unit 102 that filters signals within the communication band used for communication, i.e., communication signals. The signal filtering unit 102 includes, for example, a low-pass filter or a band-stop filter. This signal filtering unit 102 is used as a signal distortion filter 104.

[0152] When the vehicle-mounted device 400 communicates with other vehicle-mounted devices, the signal deformation unit 410 (signal distortion filter 104) can be provided on the vehicle-mounted device 400.

[0153] Reference Figure 19 In addition to having a signal distortion section 410 (signal distortion filter 104), the vehicle-mounted device 400 also has, for example, features similar to the first vehicle-mounted device 60 (see reference 104). Figure 7 The same structure applies. Specifically, the vehicle-mounted device 400 includes a communication unit 462, an electrical board 464 on which the communication unit 462 is mounted, and a connector 466 disposed on the electrical board 464. A communication line 468 (transmission line) is provided on the electrical board 464 to electrically connect the communication unit 462 and the connector 466. The connector 466 includes a housing 466a (connector body).

[0154] The communication unit 462 includes a signal waveform correction circuit 122. The vehicle-mounted device 400 also includes the aforementioned signal distortion filter 104. The signal filtering unit 102 (signal distortion filter 104) is disposed, for example, within the housing 466a of the connector 466. More specifically, the end of the communication line 468 is located within the housing 466a of the connector 466, and the signal filtering unit 102 is disposed, for example, within the communication line 468 within the housing 466a. The signal distortion filter 104 may be a low-pass filter or a band-stop filter.

[0155] With this configuration of the vehicle-mounted device 400, communication security can be improved through a simpler structure.

[0156] The other structures are the same as in the first embodiment.

[0157] (Modified Example)

[0158] The signal filtering unit 102 (signal distortion filter 104) can also be located in a part other than the connector 466, such as the electrical board 464. (See reference...) Figure 20 The position of the signal filtering unit 102 (signal distortion filter 104) of the modified vehicle-mounted device 400A is relative to that of the vehicle-mounted device 400 (see reference). Figure 19 The structure of the vehicle-mounted device 400A is the same as that of the vehicle-mounted device 400.

[0159] In the vehicle-mounted device 400A, a signal filtering unit 102 (signal distortion filter 104) is provided on the communication line 468 of the electrical board 464. Furthermore, the signal distortion filter 104 can be a low-pass filter or a band-stop filter.

[0160] In the modified vehicle-mounted device 400A, the same effect as in the fourth embodiment is also achieved.

[0161] (Fifth Implementation)

[0162] In the third embodiment described above, an example is shown where a signal correction unit (signal correction filter) is disposed in the wiring harness. However, this disclosure is not limited to such embodiments. The signal correction unit may, for example, be a structure disposed in an in-vehicle device.

[0163] Reference Figure 21 An example of an on-board device including a signal correction unit will be described. The on-board device 500 in this embodiment is an ECU. The on-board device 500 has the same structure as the ECU1 or ECU2 in the third embodiment, except that it includes a signal correction unit 510.

[0164] The signal correction unit 510 has the same signal correction unit 180 as in the third embodiment (see...). Figure 12 The same structure applies. Specifically, the signal correction unit 510 includes a signal filtering unit 182 that filters signals within the communication band used for communication, i.e., communication signals. The signal filtering unit 182 includes, for example, a low-pass filter or a band-stop filter. The signal filtering unit 182 functions as a signal correction filter 184.

[0165] When the vehicle-mounted device 500 communicates with other vehicle-mounted devices, the signal correction unit 510 (signal correction filter 184) can also be installed in other vehicle-mounted devices.

[0166] The signal correction filter 184 can be a low-pass filter or a band-stop filter. As shown in the fourth embodiment, the signal correction filter 184 can be a structure provided in the connector of the vehicle device 500, or it can be a structure provided in the electrical board of the vehicle device 500.

[0167] With this configuration of the vehicle-mounted device 500, communication security can be improved through a simpler structure.

[0168] The other structures are the same as in the third embodiment.

[0169] (Modified Example)

[0170] In the above embodiments, the number of communication lines can also be multiple.

[0171] In the above embodiments, an example is shown where the amplifier of the on-board unit (ECU) functions as a buffer circuit (input / output buffer), but this disclosure is not limited to such embodiments. The amplifier of the on-board unit (ECU) may also be a structure that functions as an amplifier circuit. In this case, the transceiver circuit of the on-board unit (ECU) may also be configured as an amplifier circuit PA (Power Amplifier) / LNA (Low Noise Amplifier). Specifically, the amplifier of the transmitting circuit in the on-board unit may be configured as PA, and the amplifier of the receiving circuit may be configured as LAN.

[0172] In the above embodiments, a structure in which the vehicle-mounted device is an ECU is shown, but this disclosure is not limited to such embodiments. The vehicle-mounted device may also be a device other than an ECU.

[0173] In the above embodiments, an example is shown where the signal waveform correction circuit or signal waveform deformation circuit is provided in the communication unit, but this disclosure is not limited to such embodiments. The signal waveform correction circuit or signal waveform deformation circuit may also be a structure provided outside the communication unit.

[0174] Implementation methods obtained by appropriately combining the technologies disclosed above are also included within the scope of this disclosure.

[0175] The embodiments disclosed herein are merely illustrative and are not limited to the embodiments described above. The scope of this disclosure is based on the detailed description of the invention and is indicated by the claims, including all modifications within the meaning and scope equivalent to the statements contained therein.

[0176] Label Explanation

[0177] 20, 68, 78, 82, 210, 468 communication lines

[0178] 40, 40A system

[0179] 50, 300 security systems

[0180] 60, 60A First Vehicle-Mounted Device

[0181] 62, 62A First Communications Department

[0182] 64 First Electrical Board

[0183] 66, 76, 466 connectors

[0184] 70, 70A Second Vehicle-Mounted Device

[0185] 72, 72A Second Communications Department

[0186] 74 Second Electrical Board

[0187] 80, 80A, 200 wiring harness

[0188] 84, 230 First Connector

[0189] 84a, 86a, 466a casing

[0190] 86, 240 Second Connector

[0191] 100, 160, 410 signal deformation section

[0192] 102, 182, 250 signal filtering section

[0193] 104, 252 signal distortion filters

[0194] 120, 180, 510 signal correction department

[0195] 122, 122a, 122b Signal waveform correction circuits

[0196] 130, 132, 140, 142 amplifiers

[0197] 150 low-pass filter

[0198] 152 Band-stop filter

[0199] 154, 254 Open-Circuit Short-Line Filters

[0200] 162, 162a, 162b Signal Waveform Deformation Circuit

[0201] 220 Retaining component

[0202] 184 signal correction filter

[0203] 400, 400A, 500 vehicle-mounted devices

[0204] 462 Ministry of Communications

[0205] 464 Electrical Board

Claims

1. A security system for connecting a first communication unit and a second communication unit via a communication line, wherein, The security system includes: A signal deformation section that deforms the signal waveform of the communication signal transmitted in the communication; and The signal correction unit corrects the signal waveform after it has been deformed by the signal deformation unit.

2. The security system according to claim 1, wherein, The signal deformation unit includes a signal filtering unit, which filters the communication signal, which is a signal within the communication band used for the communication. The signal correction unit includes a signal waveform correction circuit, which corrects the signal waveform after it has been deformed by the signal filtering unit.

3. The security system according to claim 2, wherein, The signal filtering unit filters the communication signal sent by the first communication unit. The second communication unit includes the signal waveform correction circuit.

4. The security system according to claim 1, wherein, The signal deformation unit includes a signal waveform deformation circuit that deforms the signal waveform of the communication signal. The signal correction unit includes a signal filtering unit, which filters the signal waveform after it has been deformed by the signal waveform deformation circuit.

5. The security system according to claim 4, wherein, The first communication unit includes the signal waveform deformation circuit. The signal waveform deformation circuit deforms the signal waveform of the communication signal transmitted by the first communication unit. The signal filtering unit is installed on the transmission line up to the point where the second communication unit receives the communication signal.

6. The security system according to any one of claims 2 to 5, wherein, The signal filtering section includes a low-pass filter or a band-stop filter.

7. The security system according to any one of claims 2 to 6, wherein, The communication between the first communication unit and the second communication unit is connected via a wire harness. The wiring harness includes: The communication line; and Connector, which connects to the end of the communication line. The signal filtering section is disposed on the communication line or the connector.

8. The security system according to claim 7, wherein, The wiring harness also includes a sheet-like retaining member that holds the communication line.

9. The security system according to any one of claims 2 to 6, wherein, The signal filtering unit is disposed on at least one of a first electrical board on which the first communication unit is mounted, a connector disposed on the first electrical board, a second electrical board on which the second communication unit is mounted, and a connector disposed on the second electrical board.

10. A wire harness for connecting a first communication unit and a second communication unit, wherein, The wiring harness includes: Communication lines; A connector, which connects to the end of the communication line; and A signal filtering unit is provided on the communication line or the connector to filter the communication signals transmitted in the communication.

11. The wire harness according to claim 10, wherein, The signal filtering section includes a low-pass filter or a band-stop filter.

12. The wire harness according to claim 10 or 11, wherein, The wiring harness also includes a sheet-like retaining member that holds the communication line.

13. A connector for a system of connecting a first communication unit and a second communication unit via a communication line, wherein, The connector includes: Casing; and A signal filtering unit is disposed inside the housing to filter the communication signals transmitted in the communication.

14. A vehicle-mounted device that communicates with other vehicle-mounted devices via a communication line, wherein, The vehicle-mounted device includes a communication unit that communicates with other vehicle-mounted devices. The communication unit includes a signal waveform correction circuit that corrects the distortion of the signal waveform when the communication signal transmitted from the other vehicle-mounted device is distorted.

15. The vehicle-mounted device according to claim 14, wherein, The vehicle-mounted device also includes a signal filtering unit, which filters the signal waveform of the transmitted signal sent to the other vehicle-mounted devices to avoid distortion.

16. A vehicle-mounted device that communicates with other vehicle-mounted devices via a communication line, wherein, The vehicle-mounted device includes a communication unit that communicates with other vehicle-mounted devices. The communication unit includes a signal waveform deformation circuit that deforms the signal waveform of a transmitted signal sent to the other vehicle-mounted device.

17. The vehicle-mounted device according to claim 16, wherein, The vehicle-mounted device also includes a signal filtering unit, which filters the signal waveform of a communication signal transmitted from the other vehicle-mounted device to correct the distortion of the signal waveform.

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