KR20140090780A - Car visible-light-communication system - Google Patents

Abstract

The visible light wireless communication system includes a VLC transmitter and a VLC receiver. The VLC transmitter generates a visible light signal including a signal. The VLC receiving unit includes a light receiving module, and receives the visible light of the signal generated by the VLC transmitting unit, and analyzes the signal. The light receiving module of the VLC receiving unit includes a polarizing member and a light receiving sensor. The polarizing member polarizes the external visible light and the signal visible light. The light receiving sensor receives the external visible light and the polarized signal visible light polarized by the polarizing member, disposed at a lower portion of the polarizing member.

Description

TECHNICAL FIELD [0001] The present invention relates to a visible light communication system for a vehicle,

The present invention relates to a visible light wireless communication system, and more particularly, to a visible light wireless communication system mounted in a vehicle.

2. Description of the Related Art Generally, visible light communication (VLC) includes a signal including visible light generated in an illumination such as a light emitting diode (LED) and transmits the signal through a light receiving sensor capable of receiving visible light Means performing wireless communication. Recently, with the development of lighting technology and wireless communication technology, the need for new convergence technology has arisen and recently developed technology. Meanwhile, the signal included in the visible light is modulatively transmitted by various combinations of the number of blinking times of visible light, time, and the like.

Although the visible light wireless communication technology has been applied in various ways because of its advantage of being able to communicate by including a signal in a general illumination, it is difficult to transmit the light including the signal due to the interference of the illumination including the signal, Problems arise. Especially, the problem of such signal transmission becomes serious in outdoor daytime where outdoor light such as sunlight is stronger than a room with weak outside light, and it is necessary to solve this problem. Furthermore, a technique for eliminating interference due to external light as described above has not been specifically developed yet.

SUMMARY OF THE INVENTION Accordingly, the present invention has been made keeping in mind the above problems occurring in the prior art, and it is an object of the present invention to provide a visible light wireless communication system for a vehicle which reduces interference of external light.

A visible light wireless communication system according to an embodiment of the present invention includes a VLC transmitter and a VLC receiver. The VLC transmitter generates a visible light signal including a signal. The VLC receiving unit includes a light receiving module, and receives the visible light of the signal generated by the VLC transmitting unit, and analyzes the signal. The light receiving module of the VLC receiving unit includes a polarizing member and a light receiving sensor. The polarizing member polarizes the external visible light and the signal visible light. The light receiving sensor receives the external visible light and the polarized signal visible light polarized by the polarizing member, disposed at a lower portion of the polarizing member.

In one embodiment, the signal visible light may be generated through a light emitting diode (LED).

In one embodiment, the VLC transmitter is mounted on a signal lamp or the rear of the vehicle, and the light receiving module of the VLC receiver may be mounted on a front surface of the vehicle.

In one embodiment, the light receiving module may be mounted adjacent to a headlight of a vehicle.

In one embodiment, the polarizing member can block the passage of the external visible light and the horizontal light of the signal visible light.

In one embodiment, the light receiving module may further include a substrate on which the light receiving sensor is mounted, and a cover portion that protects the polarizing member and the light receiving sensor from the upper portion of the polarizing member.

In one embodiment, the signal included in the signal visible light may be an audio signal, a video signal, or a data signal.

According to the present invention, since the light receiving module of the VLC receiving unit includes the polarizing member and polarizes incident light, incidence of external visible light not including a signal can be blocked, and the signal interpretation power of the VLC receiving unit can be improved.

In particular, since the polarizing member blocks the horizontal light component of the incident light, it is possible to pass the visible light while shielding external visible light, which is mostly horizontal light, so that the signal interpreting ability of the VLC receiving unit can be improved.

Since the light receiving module of the VLC receiving unit is mounted adjacent to the headlight of the vehicle, it is minimized that the incoming external visible light directly reaches the light receiving module, and the incoming light signal reaches the light receiving module directly. . In particular, when the VLC transmitter is mounted on the signal lamp or the rear of the vehicle, the light receiving module is disposed substantially in parallel with the VLC transmitter, so that the ratio of directly receiving the visible light can be improved.

Also, since the signal visible light is generated through the LED, it can transmit various signals such as audio, video, or data signals by modulating the number of blinking, time, brightness and the like in a range of frequencies that humans can not recognize.

1 is a block diagram showing a conventional visible light wireless communication system.
2 is a conceptual diagram showing a visible light wireless communication system according to the present embodiment.
3 is a front view showing a vehicle equipped with the visible light wireless communication system of Fig.
4 is a sectional view showing the light receiving module of Fig.
5A and 5B are conceptual diagrams showing application examples of the visible light wireless communication system of FIG.

While the present invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not limited to the disclosed embodiments. It is to be understood, however, that the invention is not intended to be limited to the particular forms disclosed, but on the contrary, is intended to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention. Like reference numerals are used for like elements in describing each drawing. The terms first, second, etc. may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another. The terminology used in this application is used only to describe a specific embodiment and is not intended to limit the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. In the present application, the term "comprises" or "comprising ", etc. is intended to specify that there is a stated feature, figure, step, operation, component, But do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, parts, or combinations thereof.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries are to be interpreted as having a meaning consistent with the contextual meaning of the related art and are to be interpreted as either ideal or overly formal in the sense of the present application Do not.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a block diagram showing a conventional visible light wireless communication system.

Referring to FIG. 1, a conventional visible light wireless communication system 1 includes a visible light communication (VLC) transmitter 10 and a VLC receiver 20. The VLC transmitter 10 includes a memory 11, a VLC transmission processor 12, a VLC transmission control circuit 13, a VLC driving circuit 14, and a light source 15 to generate a visible light signal containing a signal . The VLC receiver 20 includes a photo diode 21, a VLC receiver decoder 22, a VLC receiver processor 23 and a memory 24 and receives signals generated by the VLC transmitter 10 After receiving the visible light, the signal interprets the signal included in the visible light.

Specifically, the signal stored in the memory 11 is modulated by processing the signal so that the VLC transmission processor 12 can transmit / receive the visible light, and then the VLC transmission control circuit 13 controls the VLC transmission / The VLC driving circuit 14 controls the VLC driving circuit 14 to generate a visible light by controlling the blinking time, frequency or brightness of the light source 15.

The visible light provided to the outside is received through the photodiode 21 of the VLC receiving unit 20. The VLC receiving decoding unit 22 analyzes the modulated signal included in the light received by the photodiode 21 To the VLC reception processor 23. Thereafter, the VLC reception processor 23 processes the modulated signal to the memory 11 as opposed to the VLC transmission processor 12, and the memory 11 stores the transmitted signal, Provide the necessary information to the user.

Thus, by modulating the time, the number of times, the brightness, or the like of the visible light to provide necessary information, the user can receive the necessary information immediately in addition to the role as the illumination that the visible light generally has.

2 is a conceptual diagram showing a visible light wireless communication system according to the present embodiment.

2, the visible light wireless communication system 2 according to the present embodiment includes a VLC receiving unit including a light receiving module 110, and the VLC receiving unit including the light receiving module 110 is mounted on the vehicle 100 do. In this case, the VLC transmitting unit 200, which generates visible light received from the VLC receiving unit (hereinafter, referred to as 'visible light including a signal generated by the VLC transmitting unit and receiving a signal'), . Also, in consideration of the maximum communication distance of the visible light wireless communication, the interval between the VLC transmitting unit 200 and the vehicle 100 may be within a maximum of 20 m.

1, the VLC transmission unit 200 includes a memory, a VLC transmission processor, a VLC driving circuit, and a VLC transmission control circuit, and includes a signal through the light source 210 to the outside And generates a visible light 220 as a visible light. In this case, a light emitting diode (LED) is used as the light source 210. The LED can easily control the number of blinks, the time, the brightness, etc. through dimming control, so that various types of signals can be modularized and transmitted together with visible light within a range not recognized by a human being. That is, the function as a lighting device and the function of signal transmission can be performed simultaneously.

1, the VLC receiving unit includes a VLC receiving decoder, a VLC receiving processor, and a memory, and a signal received through the light receiving module 110 includes a visible light 220 To analyze the signal. In this case, the components of the VLC receiving unit other than the light receiving module 110 may be modularized and mounted at an arbitrary position inside the vehicle 100.

The light receiving module 110 is mounted on the front surface of the vehicle 100 because the signal visible light 220 needs to be received. However, the light received through the light receiving module 110 includes external visible rays 300 and 310 not including the visible light 220 generated from the light source 210 of the VLC transmitting unit 200 .

Particularly, when the light receiving module 110 directly receives the external visible light 300 or 310 as visible light not containing a signal, the visible light communication failure occurs. In order to solve this problem, the light receiving module 110 includes the polarizing member 114 in this embodiment. The polarizing member 114 polarizes the external visible light 300 and 310 and the signal visible light 220 and provides the polarized light to the light receiving sensor 112 of the light receiving module 110.

The visible light 300 and the fading signal light 310 may include natural light 300 and fading signal light 310. The natural light 300 and the fading signal light 310 may be transmitted directly to the light receiving module 110 of the vehicle, Most of it is reflected on the paper surface 400 and then transmitted. The natural light 300 and the fading signal light 310 are transformed into the natural light 301 having a normal light component and the fading optical signal 311 having a normal light component while being reflected from the ground 400. Therefore, if the light receiving module 110 includes the polarizing member 114 blocking the horizontal light component, both the natural light 301 having the horizontal light component and the fading signal light 311 having the horizontal light component are blocked . Of course, the polarizing member 114 may also block the normal light component of the signal visible light 220. However, even when the polarizing member 114 blocks the normal light component of the signal visible light 220, the signal passes through the vertical light component of the visible light 220, And it is not difficult to interpret the signal in the VLC receiving unit.

As described above, when the polarizing member 114 blocks the horizontal light component, only the visible light 220 having a vertical light component passing through the polarizing member 114 is provided to the light receiving sensor 112. Thus, the light receiving sensor 112 can block external visible rays 300 and 310 and receive only the signal visible light 220, thereby improving the signal interpreting ability of the visible light wireless communication system.

The signal included in the signal visible light 220 may include various signals such as an audio signal, a video signal, and a data signal.

3 is a front view showing a vehicle equipped with the visible light wireless communication system of Fig.

Referring to FIG. 3, the light receiving module 110 of the visible light wireless communication system according to the present embodiment is mounted on the front surface of the vehicle 100. 3 is mounted between the radiator grill and the headlight 120 of the vehicle 100. However, the present invention is not limited thereto, and it may be sufficient to mount the vehicle 100 on the front surface of the vehicle 100 forward . Further, the light receiving module 110 may be integrally formed with the headlight 120 and mounted on the front surface of the vehicle 100.

 2, even when the light receiving module 110 blocks external visible light 301 and 311 having a horizontal light component reflected by the ground 400 including the polarizing member 114, the light receiving module 110 The external visible light 300, 310 directly transmitted to the light source 300 can not be completely excluded. Therefore, it is necessary to minimize the external visible light (300, 310) directly transmitted to the light receiving module (110).

The light receiving module 110 is mounted on the front surface of the vehicle 100 either adjacent to the headlight 120 or integrally with the headlight 120 and further connected to the light receiving module 110 May be disposed to face the paper surface 400 relatively. Therefore, it is possible to minimize the arrival of the visible rays 300 and 310 directly to the light receiving module 110 and to allow the signal visible light 220 to directly reach the light receiving module 110 within a close communication distance Can be maximized.

The light receiving module 100 may be mounted on the rear surface of the vehicle or the rear of the vehicle so that the VLC transmitter 100 may be mounted on the VLC And can be arranged substantially parallel to the transmitting portion. Therefore, the direct reception ratio of the visible light 220 by the light receiving module 100 can be improved, and the direct reception ratio of the external visible light 300, 310 can be reduced.

4 is a sectional view showing the light receiving module of Fig.

4, the light receiving module 110 includes a substrate 111, a light receiving sensor 112 mounted on the substrate 111, a polarizing member 114 disposed on the light receiving sensor 112, And a cover portion 113 covering upper and side portions of the polarizing member 114 and the light receiving sensor 112.

The polarizing member 114 may be disposed on the inner surface of the cover part 113 in the form of a polarizing plate or on the inner surface of the cover part 113 in the form of a polarizing film. In addition, the cover portion 113 is formed of a transparent material to improve the incidence of visible light.

5A and 5B are conceptual diagrams showing application examples of the visible light wireless communication system of FIG.

5A, the VLC transmitting unit 220 is mounted on a traffic light, and the light receiving module 130 of the VLC receiving unit is mounted on a front surface of the vehicle 101. Thus, when the vehicle 101 stops according to a stop signal of a traffic light, when the signal visible light 221 is generated together with the stop signal of the traffic light, the light receiving module 130 receives the visible light 221 to perform visible light wireless communication, The necessary information is communicated to the user.

In this case, the light receiving module 130 receives the direct signal visible light 221 from the adjacent signal light but mounts it in the direction facing the traffic light on the front surface of the vehicle 101 so as not to directly receive the external visible light . Since the signal light can be positioned in various directions depending on the position of the vehicle, the light receiving module 130 can be constructed so that the light receiving direction of the light receiving module 130 can be changed so that the light receiving direction of the light receiving module 130 is directed to a nearby traffic light .

5B, the VLC transmitting unit 230 is mounted on the rear surface of the vehicle 102 on which the tail lamp is mounted, and the light receiving module 140 of the VLC receiving unit is mounted on the front surface of the vehicle 102 . Thus, when the vehicles 102 are running continuously or continuously, that is, when the interval between the vehicles 102 is within the range of the communication distance at which the visible light wireless communication is possible, When the signal visible light 222 is generated together, the light receiving module 140 of the trailing vehicle receives the signal visible light 222 to perform visible light wireless communication, and necessary information is transmitted to the user.

Similarly, in this case, the light-receiving module 140 receives the signal visible light 221 directly from the preceding vehicle 102, but does not directly receive the visible light from the front vehicle 102, And can be mounted facing the ground.

According to the embodiments of the present invention as described above, since the light receiving module of the VLC receiving unit polarizes the incident light including the polarization member, it is possible to block the incidence of external visible light not including the signal, Can be improved.

In particular, since the polarizing member blocks the horizontal light component of the incident light, it is possible to pass the visible light while shielding external visible light, which is mostly horizontal light, so that the signal interpreting ability of the VLC receiving unit can be improved.

Since the light receiving module of the VLC receiving unit is mounted adjacent to the headlight of the vehicle, it is minimized that the incoming external visible light directly reaches the light receiving module, and the incoming light signal reaches the light receiving module directly. . In particular, when the VLC transmitter is mounted on the signal lamp or the rear of the vehicle, the light receiving module is disposed substantially in parallel with the VLC transmitter, so that the ratio of directly receiving the visible light can be improved.

In addition, since the signal visible light is generated through the LED, it can modulate the number of blinks in a frequency range not recognized by a human being and transmit various signals such as audio, video, or data signals.

INDUSTRIAL APPLICABILITY The visible light wireless communication system according to the present invention is applicable to a vehicle and the like and has industrial applicability that can be used for visible light wireless communication.

1: visible light wireless communication system 10: VLC transmitter
20: VLC receiver 100: Vehicle
110: light receiving module 112: light receiving sensor
113: cover part 114: polarizing member

Claims (7)

A visible light communication (VLC) transmitter for generating a visible light signal including a signal; And
And a VLC receiver including a light receiving module for receiving the visible light of the VLC transmitter and analyzing the received light,
The light receiving module of the VLC receiving unit includes:
A polarizing member for polarizing the external visible light and the signal visible light,
And a light receiving sensor disposed at a lower portion of the polarizing member for receiving external visible light and polarized signal visible light polarized by the polarizing member. 2. The visible light wireless communication system according to claim 1, wherein the signal visible light is generated through a light emitting diode (LED). [3] The system of claim 2, wherein the VLC transmitter is mounted on a signal lamp or a rear end of the vehicle, and the light receiving module of the VLC receiver is mounted on a front surface of the vehicle. The visible light wireless communication system according to claim 3, wherein the light receiving module is mounted adjacent to a headlight of a vehicle. The visible light wireless communication system according to claim 1, wherein the polarizing member blocks passage of the horizontal light of the visible light and the visible light. 6. The visible light wireless communication system according to claim 5, wherein the light receiving module further includes a substrate on which the light receiving sensor is mounted, and a cover portion that protects the polarizing member and the light receiving sensor from an upper portion of the polarizing member. 2. The visible light wireless communication system according to claim 1, wherein the signal included in the visible light is an audio signal, a video signal, or a data signal.

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