"A method and an electronic system for communicating digital data between an electronic operating unit and an electronic control unit, and a method and an image capture system for communicating digital image data between an image capture device and an electronic control unit"

The present invention relates to a method for communicating digital data between an electronic operating unit and an electronic control unit, and in particular, though not limited to a method for communicating an image capture device with an electronic control unit to relay digital image data representative of an image captured by the image capture device to the electronic control unit. The invention also relates to an electronic system comprising an electronic operating unit operating under the control of an electronic control unit whereby digital data is communicated from the electronic operating unit to the electronic control unit, and in particular, though not limited to, an image capture system for communicating digital image data from an image capture device to an electronic control unit.

Image capture devices such as electronic cameras, for example, cameras which are commonly referred to as digital cameras, are now used in motor vehicles for providing images of the environment external of the motor vehicle to the driver. Such image capture devices may be mounted on the rear of the motor vehicle and directed in a downwardly or rearwardly direction for capturing an image of the ground to the rear of the motor vehicle or for capturing an image looking rearwardly from the vehicle. Such rear mounted image capture devices may also be directed to capture an image looking rearwardly of the motor vehicle, a part of which would include an image of the ground to the rear of the vehicle and another part of which would include an image to the rear of the vehicle above the horizon.

Such image capture devices may also be mounted in side mirrors of a motor vehicle for capturing an image of the ground along a corresponding side of the motor vehicle, as well as to the rear of the motor vehicle. In general, rearwardly mounted image capture devices and image capture devices mounted in the side mirrors of a motor vehicle are provided to produce images for assisting a driver in manoeuvring the motor vehicle in a relatively confined space.

Such image capture devices may also be mounted on the side of a motor vehicle towards the front thereof and directed in a generally sidewardly direction for capturing images looking sidewardly outwardly of the motor vehicle on respective sides thereof for assisting a driver entering onto a main thoroughfare from a relatively concealed side road, driveway or the like.

In general, an electronic control unit is provided in the motor vehicle for controlling the operation of such image capture devices, and for processing signals received from the image capture devices, in order to produce a signal representative of a processed image captured by one or more of the image capture devices for relaying to a visual display screen on which the processed image is displayed to the driver. Such visual display screens in general are mounted on the dashboard of the motor vehicle within the field of view of the driver.

It is not uncommon for a motor vehicle to be provided with up to five image capture devices, all of which must be separately powered and controlled from a single central control unit. This, thus, requires hardwiring the image capture devices separately to the electronic control unit. In image capture systems known heretofore, each image capture device is powered from the electronic control unit via a power line, which requires two wires, namely, a power wire and a ground wire from the electronic control unit to the corresponding image capture device. Typically, data signals representative of images captured by the image capture devices are converted to digital form by respective analogue-to-digital converters which are located in the respective image capture devices. Typically the digital image data is relayed from the image capture devices to the electronic control unit as differential signals. Relaying such differential signals to the electronic control unit requires two wires and a ground wire from each image capture device to the electronic control unit. Control of the settings, functioning and operation, as well as diagnostics of each image capture device is carried out using a local interconnection network (LIN) protocol on a LIN line, which facilitates two-way digital communication between the electronic control unit and the corresponding image capture device. Each LIN line requires two wires, one for carrying digital control and data signals, and the other a

ground wire.

It is possible for the LIN line and the power line between each camera and the electronic control unit share a single ground line extending between the image capture device and the electronic control unit. The digital control and data signals on the LIN line between each image capture device and the electronic control unit operate typically at a baud rate of 20 Kbaud. The differential signal which carries the digital image data representative of the image captured by each image capture device, in general, operates in the range of 600 MHz to 1 GHz. Because of the difference in operating speeds of the differential signal and the digital control and data signal on the LIN line of each image capture device, known systems require two separate ground wires for the differential signal and the digital control and data signal on the LIN line in order to minimise interference between the differential signal and the digital control and data signal, one ground wire being provided for the differential signal, and the other ground wire being provided for the LIN line.

However, even by sharing the ground line between the power line and the LIN line, six connections are required between each image capture device and the electronic control unit. Thus, in a motor vehicle which comprises five image capture devices, since each image capture device requires six connections to the electronic control unit, the total number of connections required to connect the five image capture devices to the electronic control unit is thirty connections. This results in significant costs being incurred in order to provide for the coupling of the five image capture devices to the electronic control unit. Firstly, since most electronic control units are provided in the form of an integrated circuit, in order to support five image capture devices, thirty pins are required from the integrated circuit which adds significantly to the cost of producing the integrated circuit, and in turn the electronic control unit. Secondly, since each image capture device requires six wires to connect the image capture device to the electronic control unit, the number of wires required to support five image capture devices is thirty wires, which results in a relatively high copper requirement, and thus further adds to installation cost.

There is therefore a need for a method for communicating digital image data

between an image capture device and an electronic control unit which addresses at least some of the problems of known methods.

The present invention is directed towards providing such a method for communicating digital image data between an image capture device and an electronic control unit, and the invention is also directed towards such a method for communicating digital data between an electronic operating unit and an electronic control unit. The invention is also directed towards providing an electronic system which comprises an electronic control unit and an electronic operating unit in which digital data is communicated from the electronic operating unit to the electronic control unit, and the invention is also directed towards an image capture system in which installation costs of the image capture system are minimised.

According to the invention there is provided a method for communicating digital data between an electronic operating unit and an electronic control unit, the method comprising: providing a pair of mutually electrically insulated elongated first wires to carry respective signals of a differential signal representative of the digital data from the electronic operating unit to the electronic control unit, providing an elongated second wire electrically insulated from the first wires to carry a digital control signal between the electronic control unit and the electronic operating unit for control and operation of the electronic operating unit, providing an elongated third wire electrically insulated from the first and second wires to provide power from the electronic control unit to the electronic operating unit, and providing an elongated electrically conductive shield extending around and electrically insulated from the first, second and third wires and extending along the first, second and third wires for electromagnetic shielding thereof, the shield being adapted for coupling to a ground of the electronic control unit and to a ground of the electronic operating unit for providing a common ground for the differential signal carried on the first wires, the digital control signal carried on the second wire, and the power supply carried on the third wire.

In one embodiment of the invention the shield is provided as a flexible shield. Preferably, the shield comprises a woven wire shield. Advantageously, the shield defines an elongated bore for accommodating the first, second and third wires therethrough.

In another embodiment of the invention an electrically insulating sleeve of electrically insulating material having a bore extending longitudinally therethrough is provided for accommodating the shield.

In a further embodiment of the invention the pair of first wires are provided by a twisted pair.

In another embodiment of the invention the second and third wires are provided as a twisted pair separate from the first wires.

Preferably, the second wire is adapted for two-way communications for communicating the digital control signal and digital data signals for controlling at least one of settings, functions and operation of the electronic operating unit, and for relaying digital signals from the electronic operating unit to the electronic control unit for diagnosing faults in the electronic operating unit.

In one embodiment of the invention the electronic control unit is adapted for processing the digital data signals on the second wire from the electronic operating unit for fault diagnosis.

Preferably, the second wire is adapted for communicating between the electronic control unit and the electronic operating unit in accordance with a LIN protocol.

Advantageously, the second wire is adapted for operating at a baud rate of up to 20

Kbaud.

Preferably, the first wires are adapted for accommodating the differential signal at a frequency of up to 1 GHz. Advantageously, the first wires are adapted for accommodating the differential signal at a frequency in the range of 600 MHz to

1 GHz. Ideally, the first wires are adapted for accommodating the differential signal at a frequency in the range of 680 MHz to 800 MHz.

Preferably, the electronic operating unit and the electronic control unit are adapted for mounting in a motor vehicle. Advantageously, the electronic operating unit comprises an image capture device. Preferably, the image capture device comprises an electronic camera. Advantageously, the image capture device comprises a digital camera.

In one embodiment of the invention the electronic operating unit is programmable.

In another embodiment of the invention the electronic control unit is programmable.

The invention also provides a method for communicating digital data between an electronic operating unit and an electronic control unit, the method comprising: communicating the digital data as a differential signal, parts of the differential signal being carried on respective ones of a pair of mutually electrically insulated elongated first wires from the electronic operating unit to the electronic control unit, controlling the electronic operating unit by a digital control signal carried on an elongated second wire between the electronic control unit and the electronic operating unit, the second wire being electrically insulated from the first wires, powering the electronic operating unit by a power supply from the electronic control unit on an elongated third wire electrically insulated from the first and second wires, and providing a common ground between the electronic operating unit and the electronic control unit for the differential signal carried on the first wires, the digital control signal carried on the second wire, and the power supply carried on the third wire by an elongated electrically conductive shield extending around and electrically insulated from the first, second and third wires and extending along the first, second and third wires, and providing the shield to electromagnetically shield the first, second and third wires.

Additionally, the invention provides a method for communicating an image capture

device with an electronic control unit to relay digital image data representative of an image captured by the image capture device to the electronic control unit, the method comprising: communicating the digital image data as a differential signal, parts of the differential signal being carried on respective ones of a pair of mutually electrically insulated elongated first wires from the image capture device to the electronic control unit, controlling the image capture device by a digital control signal carried on an elongated second wire between the electronic control unit and the image capture device, the second wire being electrically insulated from the first wires, powering the image capture device by a power supply from the electronic control unit on an elongated third wire electrically insulated from the first and second wires, and providing a common ground between the image capture device and the electronic control unit for the differential signal carried on the first wires, the digital control signal carried on the second wire, and the power supply carried on the third wire by an elongated electrically conductive shield extending around and electrically insulated from the first, second and third wires and extending along the first, second and third wires, and providing the shield to electromagnetically shield the first, second and third wires.

Further the invention provides an electronic system comprising an electronic control unit and an electronic operating unit operating under the control of the electronic control unit, and a cable coupling the electronic operating unit to the electronic control unit, the cable comprising: a pair of mutually electrically insulated elongated first wires coupled to the electronic control unit and to the electronic operating unit for carrying respective signals of a differential signal representative of digital data from the electronic operating unit to the electronic control unit, an elongated second wire electrically insulated from the first wires coupled to the electronic control unit and to the electronic operating unit for carrying a digital control signal for the control and operation of the electronic operating unit, an elongated third wire electrically insulated from the first and second wires

to provide power from the electronic control unit to the electronic operating unit, and an elongated electrically conductive shield extending around and electrically insulated from the first, second and third wires and extending along the first, second and third wires for electromagnetic shielding thereof, the shield being electrically coupled to a ground of the electronic control unit and to a ground of the electronic operating unit to provide a common ground for the differential signal carried on the first pair of wires, the digital control signal carried on the second wire and the power supply carried on the third wire.

The invention also provides an image capture system for a motor vehicle, the system comprising: an electronic control unit, an image capture device operating under the control of the electronic control unit, and a cable coupling the image capture device to the electronic control unit, the cable comprising: an elongated pair of mutually electrically insulated first wires coupled to the electronic control unit and to the image capture device for carrying respective signals of a differential signal representative of digital image data from the image capture device to the electronic control unit, the digital image data being representative of an image captured by the image capture device, an elongated second wire electrically insulated from the first wires and coupled to the electronic control unit and the image capture device for carrying a digital control signal for the control and operation of the image capture device, an elongated third wire electrically insulated from the first and second wires for providing power from the electronic control unit to the image capture device, and an elongated electrically conductive shield extending around and electrically insulated from the first, second and third wires and extending along the first, second and third wires for electromagnetic shielding thereof, the shield being electrically coupled to a ground of the electronic control unit and to a ground of the image capture device for providing a common ground for the differential signal carried on the first pair of wires, the digital control signal carried on the second wire and the power supply carried on the third wire.

In one embodiment of the invention the cable terminates at at least one of its ends in a connector element for connecting the cable to one of the electronic control unit and the image capture device.

In another embodiment of the invention the connector element comprises a socket connector having four spaced apart mutually electrically insulated electrically socket elements electrically coupled to the respective first, second and third wires of the cable.

Preferably, an electrically conductive electromagnetic shielding element extends around the electrically conductive socket elements and is electrically insulated therefrom, the shielding element being electrically coupled to the shield of the cable.

Advantageously, the ends of the cable terminate in respective connector elements.

In one embodiment of the invention the image capture device comprises a complementary connector element engageable with a corresponding one of the connector elements of the cable.

In another embodiment of the invention a plurality of image capture devices are provided, the image capture devices being electrically coupled to the electronic control unit by respective corresponding ones of the cables.

Preferably, the electronic control unit comprises a plurality of complementary connectors for engaging the respective connector elements of the cables of corresponding image capture devices.

Advantageously, the electronic control unit is adapted for processing the digital image data from at least two of the image capture devices and for producing a signal representative of a composite image derived from the digital image data from the at least two image capture devices for relaying to a visual display device for displaying the composite image.

In one embodiment of the invention each image capture device and the electronic control unit are adapted for mounting in a motor vehicle. Preferably, the electronic operating unit is programmable.

Advantageously, the electronic control unit is programmable.

Additionally, the invention provides a motor vehicle comprising an image capture system for capturing an image external of the motor vehicle, the image capture system being an image capture system according to the invention.

The advantages of the invention are many. By virtue of the fact that each image capture device is coupled to the electronic control unit by four wires only, namely, the pair of first wires, and the second and third wires, and by virtue of the fact that the shield of each cable forms a common ground for a differential signal on the first wires, a digital control signal on the second wire and for the power supply on the third wire, each image capture device is coupled to the electronic control unit by a pin connector having only four pins. This, thus, minimises the number of pins and wires required to couple the image capture devices to the electronic control unit. Thus, in cases where the electronic control unit is provided as an integrated circuit, the number of pins required from the integrated circuit for each image capture device is four pins only, together with one single ground pin. Thus, where a large number of image capture devices are to be coupled to the electronic control unit, the pin count required on the integrated circuit of an electronic control unit is minimised, and is significantly less than the pin count required for image capture systems known heretofore. For example, where image capture systems known heretofore required a separate ground wire for each of the digital image data, the digital control signal and the power supply, the total pin count required for each image capture device is seven. However, even in image capture systems where a ground line was shared between the power line and the digital control signal line, the pin count required for an integrated circuit of the electronic control unit is six. However, in an image capture system according to the invention which comprises five image capture devices, the pin count required of an integrated circuit of an electronic control unit is

twenty pins plus one ground pin, as opposed to either thirty or thirty-five pins in prior art image capture systems with five image capture devices. Additionally, the pin count of the integrated circuit of each image capture device can be similarly reduced to four pins.

Additionally, by reducing the number of connections between each image capture device and the electronic control unit, the number of wires required to connect the image capture devices to the electronic control unit is reduced.

Accordingly, by reducing the number of pins required in an integrated circuit of the electronic control unit and by reducing the number of wires required to connect the respective image capture devices to the electronic control unit, the cost of installing the image capture system according to the invention in a motor vehicle is minimised, and is significantly reduced relative to the cost of installing known image capture systems in a motor vehicle.

A further advantage of the invention is achieved by virtue of the fact that the first, second and third wires are electromagnetically shielded by the electrically conductive shield. Thus, the first, second and third wires are shielded from external electromagnetic interference, and similarly, electromagnetic interference from the first, second and third wires is shielded from other components of the motor vehicle.

Similar advantages are achieved from the invention when other electronic operating units besides image capture devices are coupled to an electronic control unit in accordance with the invention.

The invention will be more clearly understood from the following description of a preferred embodiment thereof, which is given by way of example only, with reference to the accompanying drawings, in which:

Fig. 1 is a block representation of an electronic system according to the invention,

Fig. 2 is a partly transverse cross-sectional side elevational view and a partly block representational view of a portion of the electronic system of Fig. 1 , and

Fig. 3 is a transverse cross-sectional end elevational view of a portion of the electronic system of Fig. 1 ,

Fig. 4 is a perspective view of a portion of the electronic system of Fig. 1 ,

Fig. 5 is a transverse cross-sectional side elevational view of a detail of the portion of Fig. 6 of the electronic system of Fig. 1 , and

Fig. 6 is a cutaway perspective view of a portion of the detail of Fig. 5.

Referring to the drawings, there is illustrated an electronic system according to the invention, which in this case is an image capture system, indicated generally by the reference numeral 1 , which is suitable for use in a motor vehicle (not shown) for presenting an image of the environment external of the motor vehicle to a driver thereof on a visual display unit 2. The visual display unit 2 is typically mounted on a dashboard of the motor vehicle within the field of view of the driver. The image capture system 1 comprises an electronic control unit 3 and a plurality of electronic operating units, namely, five image capture devices 4, which are provided by respective digital cameras. The image capture devices 4 are individually electrically coupled to the electronic control unit 3 through corresponding shielded cables 5 which are described in detail below. Each image capture device 4 is individually powered through the corresponding shielded cable 5 by the electronic control unit 3. The setting, functioning and operation of each image capture devices 4 is individually controlled by the electronic control unit 3 through the corresponding cable 5, and digital image data representative of images captured by each image capture device 4 is relayed via the corresponding shielded cable 5 to the electronic control unit 3.

The electronic control unit 3 is programmed to read and process the digital image data received from the image capture devices 4 and to produce a processed image

which is relayed via a cable 7 to the visual display unit 2 for display thereon. The processed images produced by the electronic control unit 3 are produced in response to the operating mode of the motor vehicle, and typically are produced for assisting the driver to manoeuvre the vehicle in a relatively confined area. The operation of such an image capture system in a motor vehicle will be understood by those skilled in the art.

Typically, the image capture devices 4 may include a rear mounted image capture device, for example, the image capture device 4a for producing an image of the ground to the rear of the motor vehicle, or an image looking fearwardly from the motor vehicle, or an image a part of which comprises an image of the ground to the rear of the motor vehicle and a part of which comprises an image looking to the rear of the motor vehicle above the horizon. Two of the image capture devices, for example, the image capture devices 4b may be mounted in the side mirrors of the motor vehicle and directed downwardly and angled slightly to the rear for producing respective images of the ground adjacent the corresponding side of the vehicle and extending slightly rearwardly thereof. Two of the image capture devices, for example, the image capture devices 4c may be mounted on the respective sides of the vehicle to the front thereof and directed sidewardly outwardly for producing respective images looking sidewardly of the motor vehicle for assisting a driver in exiting onto a main thoroughfare from a concealed side road or driveway.

Each shielded cable 5 which couples a corresponding one of the image capture devices 4 to the electronic control unit 3 comprises an electromagnetically shielded cable and terminates at its respective opposite ends in connector elements, namely, socket connectors 8 of the pin type for electrically coupling the cable 5 to corresponding pin connectors (not shown) of the electronic control unit 3 and the corresponding image capture device 4. Each cable 5 comprises a pair of elongated mutually electrically insulated first wires 10 around which respective electrically insulating sleeves 11 extend and which are provided in the form of a twisted pair and extend longitudinally through the cable 5. The first wires 10 are electrically coupled at the respective opposite ends to the socket connectors 8 as will be described below. An elongated second wire 12 around which an insulating sleeve 14 extends

and an elongated third wire 15 around which an insulating sleeve 16 extends are provided in the form of a twisted pair and extend longitudinally through the cable 5 and are electrically insulated from each other and from the first wires 10. The second and third wires 12 and 13 are electrically coupled at the respective opposite ends to the socket connectors 8 as will be described below.

An electrically conductive shield 17 of electrically conductive woven metal extends around the first wires 10, the second wire 12 and the third wire 15 and defines a bore 18 through which the first, second and third wires 10, 12 and 15 are accommodated between the pin connectors 8. The shield 17 extends the length of the cable 5 between the socket connectors 8 and provides electromagnetic shielding for the first, second and third wires 10, 12 and 15. A sleeve 19 of electrically insulating material extends around the shield 17 of each cable 5.

Referring now in particular to Figs. 4 and 5, each socket connector 8 comprises four mutually socket elements formed by hollow pins 20 which are mounted in a body member 21 of electrically insulating material. An electrically conductive shielding element 22 extends around the body member 21 and the hollow pins 20 and is electrically insulated from the hollow pins 20 by the body member 21 to form with the hollow pins 20 and the body member 21 the socket connector 8. The shield 17 of each cable 5 is electrically coupled to the shielding elements 22 of the corresponding pair of socket connectors 8 at the respective opposite ends thereof. The shielding element 22 of each socket connector 8 also provides electromagnetic shielding of the hollow pins 20, and is adapted for electrically coupling to one of the pin connectors (not shown) of the corresponding image capture device 4 or the electronic control unit 3 to provide electrical continuity between the shield 17 of the cable 5 and a grounded housing of the electronic control unit 3 or the image capture device 4 as the case may be. Each first wire 10 is electrically coupled to a corresponding one of the hollow pins 20 in the socket connectors 8, and each second wire 12 and each third wire 15 are electrically coupled to respective corresponding ones of the hollow pins 20 in the socket connectors 8.

In this embodiment of the invention, depending on the image capture system 1, the

digital image data from the respective image capture devices 4 are produced by the image capture devices 4 in the form of differential signals which may be at a frequency of 680 MHz or 800 MHz. The two parts of the differential signal produced by each image capture device 4 are carried on the respective first wires 10 of the corresponding cable 5 to the electronic control unit 3. The shield 17 of the corresponding cable 5 acts as the ground for the differential signal on the first wires 10. Power is supplied to each image capture device 4 from the electronic control unit 3 through the third wire 15 which acts as a power wire of the corresponding cable 5. The shield 17 of the corresponding cable 5 acts as the ground for the power supply to the corresponding image capture device 4.

The second wire 12 in each cable 5 provides two-way communication between the electronic control unit 3 and the corresponding image capture device 4. In this embodiment of the invention digital control signals from the electronic control unit 3 for controlling the settings, functioning and operation of the image capture devices 4 are carried on the second wire 12 of the corresponding cable 5 to the image capture device 4. Digital data signals indicative of the settings, functioning and operation of each image capture device 4 are read on the second wire 12 of the corresponding cable 5 by the electronic control unit 3 for facilitating controlling the image capture device 4 and for diagnosing faults therein. Communication between the electronic control unit 3 and the image capture devices 4 on the second wires 12 of the corresponding cables 5 is carried out under the LIN protocol at a baud rate of the order of 19 Kbaud to 20 Kbaud, and the shield 17 of each cable 5 acts as a ground for the LIN communications on the corresponding second wire 12. Accordingly, the shield 17 of each cable 5 provides a common ground for the differential signal on the first wires 10, the digital control and data signal on the second wire 12 and for the power supply on the third wire 15 between the electronic control unit 3 and the corresponding image capture device 4. In this embodiment of the invention the shield 17 of each cable 5 is rated to have an electromagnetic shielding effectiveness of not less than 40dB/m at 1 GHz.

The electronic control unit 3 comprises a programmable electronic device 25 which controls the operation of the image capture devices 4 through the electronic control

device 3 and in turn through the cables 5.

In use, with the image capture devices 4 appropriately mounted on the motor vehicle and coupled to the electronic control unit 3 by the shielded cables 5 with the pin connectors 8 coupled to the socket connectors (not shown) of the corresponding image capture devices 4 and the electronic control unit 3, and with the visual display unit 2 coupled to the electronic control unit 3 via the cable 7, the image capture system 1 is ready for use. The image capture devices 4 are powered up by the electronic control unit 3 under the control of the programmable electronic device 25 by the power supply on the third wires 15 of the respective shielded cables 5. The settings, functioning and operation of the image capture devices 4 is controlled by the programmable electronic device 25 of the electronic control unit 3 by digital control and data signals on the second wires 12 of the corresponding cables 5 using the LIN protocol. Digital signals for facilitating diagnosing faults which may arise in the image capture devices 4 are carried on the second wires 12 of the corresponding cables 5 also under the LIN protocol. Differential signals representative of digital image data from the image capture devices 4 are carried on the first wires 10 of the corresponding cables 5 and are read by the programmable electronic device 25 of the electronic control unit 3. The programmable electronic device 25 processes the signals read on the first wires 10 for producing digital signals representative of a processed image to be displayed on the visual display unit 2 in response to the mode of operation of the motor vehicle, which are displayed on the visual display ^" unit 2.

It has been found that by providing each cable 5 with an electrically conductive shield 17 extending around the first, second and third wires 10, 12 and 15, the electrically conductive shield 17 is capable of acting as a common ground for the differential signal on the first wires 10, the digital control and data signal on the second wire 12 and the power supply on the third wire 15. The common ground provided by the shield 17 is sufficient to adequately clamp any interference or crosstalk between the signals on the first and second wires 10 and 12 to ground, thereby preventing cross-interference and cross-talk between the signals on the first and second wires 10 and 12. Additionally, the common ground provided by the shield 17

is sufficient to adequately clamp any interference from the power supply on the third wire 15 to ground, which prevents any interference on the third wire interfering with the signals on the first and second wires 10 and 12. Accordingly, the provision of the shield 17 eliminates the need for separate ground wires being provided for the differential signal on the first wires 10 and for the LIN signals on the second wire 12. Accordingly, the pin count required for communicating between the electronic control unit 3 and each image capture device 4 is reduced to four pins.

By providing the shielding of the shield 17 of the cable 5 to have a shielding effectiveness of not less than 40 dB/m bis 1 GHz, it has been found that the signals on the first and second wires 10 and 12 are shielded from external electromagnetic interference, such as electromagnetic interference which is generated by other electric and electronic components of the motor vehicle. Further, by providing the shielding of the shield 17 of the cable 5, electric and electronic components. of the motor vehicle external of the cable 5 are also shielded from electromagnetic interference which may be generated by the signals on the first and second wires 10 and 12.

While the cables 5 have been described as carrying four wires, namely, the first pair of wires and the second and third wires in the form of respective twisted pairs, the first pair of wires and the second and third wires may be provided in any suitable mutually electrically insulated form, and needless to say, it is not necessary that the wires be provided in twisted pairs form. Additionally, if extra wires were required for the image capture devices, these could also be provided in the bore 18 of the cables 5.

While the system has been described as comprising an electronic control unit and image capture devices which are operated under the control of the electronic control unit, it is envisaged that the system may comprise any other suitable electronic operating device or devices besides an image capture device or devices.

Additionally, while the image capture devices have been described as being digital cameras, the image capture devices could in certain circumstances be analogue cameras.

Additionally, while the image capture system has been described as comprising five image capture devices, the image capture system may comprise any number of image capture devices from one upwards.