CN104079353A - Visible light communication method and system based on color modulation - Google Patents

Abstract

The invention discloses a visible light communication method and system based on color modulation. The system comprises a transmitting end used for transmitting optical waves of 2N different wave lengths and a receiving end used for receiving and analyzing the optical waves. The transmitting end is communicated with the receiving end by means of a color modulation technology, wherein a color constellation diagram in the color modulation technology comprises at least 2N constellation points, a set of binary data is mapped as a constellation point, and each constellation point corresponds to optical waves of one wave length. According to the method and system, the transmitting end generates a set of binary data, constellation points corresponding to the binary data are obtained according to the color constellation diagram, and optical waves of wave lengths corresponding to the constellation points are driven to generate and transmitted to the receiving end; the receiving end receives and analyzes the optical waves so that the constellation points corresponding to the wave lengths of the optical waves can be obtained, and therefore the binary data corresponding to the constellation points are obtained according to the color constellation diagram. The utilization rate of the frequency band in the color modulation technology is N, and the data transmission rate is increased.

Description

A kind of visible light communication method and system based on color modulation

Technical field

The present invention relates to visible light communication technical field, in particular, relate to a kind of visible light communication method and system based on color modulation.

Background technology

Along with scientific and technical development, visible light communication technology is used widely.

But in prior art, be subject in the restriction of LED (Light-Emitting Diode, light-emitting diode) modulation bandwidth, use conventional modulator approach to be difficult to realize visible light communication at a high speed.Based on this, experts and scholars have proposed the method for various increase message transmission rates in succession, as adopted supercomposed coding modulation technique, space-modulation technique and wavelength-division multiplex technique etc.

The patent No. be in the patent application document of CN201210451695.6, disclose a kind of based on RGBLED (red-green-blue LED, rgb led) multichannel wavelength division multiplexing visible light communication system, its by adopt wavelength-division multiplex technique with increase message transmission rate.But it can only realize the multiplexing of R, G, B tri-road signals, the raising of message transmission rate is very limited, and brings in and say for reception, and receiving terminal need to arrange the devices such as filter, realizes comparatively complicated.

Summary of the invention

For the problems referred to above, the invention provides a kind of visible light communication method and system based on color modulation, it utilizes simple, efficient color modulation technology to realize the high-speed communication of visible ray, and does not need receiving terminal that the devices such as filter are set, and has simplified the structure of receiving terminal.Technical scheme is as follows:

Based on an aspect of of the present present invention, the invention provides a kind of visible light communication method based on color modulation, comprise for sending 2 ⁿthe transmitting terminal of the light wave of kind of different wave length and for receiving and resolve the receiving terminal of described light wave, described N is positive integer, it is characterized in that, described transmitting terminal and described receiving terminal adopt color modulation technology to communicate, and the color planisphere in described color modulation technology comprises at least 2 ⁿindividual constellation point, wherein, one group of binary data is mapped as a described constellation point, and the light wave of a corresponding a kind of wavelength of described constellation point; Described method comprises:

Described transmitting terminal generates one group of binary data;

Described binary data is mapped to the constellation point on described color planisphere by described transmitting terminal, to obtain the constellation point corresponding with described binary data;

Described transmitting terminal drives the light wave that generates the wavelength corresponding with described constellation point;

Described receiving terminal receives described light wave, formation voltage value;

Described receiving terminal, according to described magnitude of voltage, is determined the wavelength of the light wave that described magnitude of voltage is corresponding;

Described receiving terminal obtains according to the wavelength of definite light wave the constellation point that described wavelength is corresponding, and then according to described color planisphere, demapping goes out the binary data corresponding with described constellation point on described color planisphere.

Based on another aspect of the present invention, the invention provides a kind of visible light communication system based on color modulation, comprise for sending 2 ⁿthe transmitting terminal of the light wave of kind of different wave length and for receiving and resolve the receiving terminal of described light wave, described N is positive integer, it is characterized in that, described transmitting terminal and described receiving terminal adopt color modulation technology to communicate, and the color planisphere in described color modulation technology comprises at least 2 ⁿindividual constellation point, wherein, one group of binary data is mapped as a described constellation point, and the light wave of a corresponding a kind of wavelength of described constellation point; Wherein,

Described transmitting terminal specifically comprises:

Signal source module, for generating binary data;

Mapping block, for described binary data being mapped to the constellation point on described color planisphere, to obtain the constellation point corresponding with described binary data;

Driver module, for the described constellation point of foundation, driving light source module generates the light wave of the wavelength corresponding with described constellation point;

Light source module, for generating and sending the light wave of different wave length;

Described receiving terminal specifically comprises:

Photodiode PD detection module, for receiving after the light wave of described transmitting terminal transmission, formation voltage value;

Wavelength determination module, for the magnitude of voltage generating according to described PD detection module, determines the wavelength of the light wave that described magnitude of voltage is corresponding;

Demapping module, obtains for the wavelength of the light wave according to definite the constellation point that described wavelength is corresponding, and then according to described color planisphere, demapping goes out the binary data corresponding with described constellation point on described color planisphere.

Alternatively, described light source module comprises 2 ⁿthe LED of individual different colours, wherein, a corresponding a kind of wavelength of described LED;

Described driver module specifically for, drive the LED corresponding with described constellation point to generate a kind of light wave of color according to described constellation point; Or,

Described light source module comprises that one can generate 2 ⁿplant the LED of the light wave of different wave length;

Described driver element specifically for, described in driving according to described constellation point, can generate 2 ⁿthe LED that plants the light wave of different wave length generates the light wave of the wavelength corresponding with described constellation point.

Alternatively, described photodiode PD detection module comprises PD and testing circuit; Wherein,

The response sensitivity of described PD changes with the variation of optical wavelength.

Application technique scheme, a kind of visible light communication method and system based on color modulation provided by the invention comprises for sending 2 ⁿthe transmitting terminal of the light wave of kind of different wave length and for receiving and resolve the receiving terminal of light wave, N is positive integer.Wherein, transmitting terminal and receiving terminal adopt color modulation technology to communicate, and the color planisphere in its color modulation technology comprises at least 2 ⁿindividual constellation point, wherein, one group of binary data is mapped in a constellation point, and the light wave of a corresponding a kind of wavelength of constellation point.Particularly, transmitting terminal generates one group of binary data, and obtains the constellation point corresponding with binary data according to color planisphere, drives the light wave that generates the wavelength corresponding with constellation point, is sent to receiving terminal.Receiving terminal receives and resolves described light wave, to obtain the constellation point corresponding with the wavelength of light wave, and then obtains the binary data corresponding with constellation point according to color planisphere.Therefore, the present invention is loaded into information on color gamut, utilizes color modulation technology to make light wave that transmitting terminal sends different wave length to realize transfer of data.And the band efficiency of the color modulation technology in the present invention is N, has increased message transmission rate.

Meanwhile, color modulation technology can realize the high-speed communication of visible ray simply, efficiently, and the extra means such as filter are set without receiving terminal, realizes simple.

Brief description of the drawings

In order to be illustrated more clearly in the technical scheme in the embodiment of the present invention, below the accompanying drawing of required use during embodiment is described is briefly described, apparently, accompanying drawing in the following describes is only some embodiments of the present invention, for those of ordinary skill in the art, do not paying under the prerequisite of creative work, can also obtain according to these accompanying drawings other accompanying drawing.

Fig. 1 is the flow chart of a kind of visible light communication method based on color modulation provided by the invention;

Fig. 2 is the structural representation of a kind of visible light communication system based on color modulation provided by the invention;

Fig. 3 is a kind of schematic diagram that the response sensitivity of PD changes with optical wavelength;

Fig. 4 is the another kind of schematic diagram that the response sensitivity of PD changes with optical wavelength.

Embodiment

Below in conjunction with the accompanying drawing in the embodiment of the present invention, the technical scheme in the embodiment of the present invention is clearly and completely described, obviously, described embodiment is only the present invention's part embodiment, instead of whole embodiment.Based on the embodiment in the present invention, those of ordinary skill in the art, not making the every other embodiment obtaining under creative work prerequisite, belong to the scope of protection of the invention.

First inventor it should be noted that, in the present invention, and the corresponding a kind of wavelength of a kind of light wave of color.Light wave light source in the present invention can send the light wave of different colours and realize the light wave that sends different wave length.

Embodiment mono-

The visible light communication method based on color modulation of the present invention's protection comprises for sending 2 ⁿthe transmitting terminal of the light wave of kind of different wave length and for receiving and resolve the receiving terminal of described light wave, wherein N is positive integer, 2 ⁿfor the Nth power of mathematic(al) representation 2.In the present invention, transmitting terminal and receiving terminal adopt color modulation technology to communicate, and the color planisphere in its color modulation technology comprises at least 2 ⁿindividual constellation point, wherein, one group of binary data is mapped as a described constellation point, and the light wave of a corresponding a kind of wavelength of described constellation point.Particularly, refer to Fig. 1, it shows the flow chart of a kind of visible light communication method based on color modulation provided by the invention.Comprise:

Step 101: transmitting terminal generates one group of binary data.

Step 102: binary data is mapped to the constellation point on color planisphere by transmitting terminal, to obtain the constellation point corresponding with binary data.

Step 103: transmitting terminal drives the light wave that generates the wavelength corresponding with constellation point.

Step 104: receiving terminal receives light wave, formation voltage value.

Step 105: receiving terminal, according to magnitude of voltage, is determined the wavelength of the light wave that magnitude of voltage is corresponding.

Step 106: receiving terminal obtains according to the wavelength of definite light wave the constellation point that wavelength is corresponding, and then according to color planisphere, demapping goes out binary data corresponding with constellation point on color planisphere.

In the present embodiment, set up the corresponding relation of binary data and optical wavelength by color planisphere.Particularly, transmitting terminal generates one group of binary data, and according to color planisphere, binary data is mapped to the constellation point on color planisphere, to obtain the constellation point corresponding with binary data, and then drive the light wave that generates the wavelength corresponding with constellation point, be sent to receiving terminal.

Receiving terminal receives described light wave, and formation voltage value, according to magnitude of voltage, determine the wavelength of the light wave that magnitude of voltage is corresponding, and then obtain according to the wavelength of definite light wave the constellation point that wavelength is corresponding, and then according to color planisphere, demapping goes out binary data corresponding with constellation point on color planisphere.

Therefore, the present invention is loaded into information on color gamut, utilizes color modulation technology to make light wave that transmitting terminal sends different wave length to realize transfer of data.The band efficiency of the color modulation technology in the present invention is N, has increased message transmission rate.

Embodiment bis-

Refer to Fig. 2, the structural representation that it shows a kind of visible light communication system based on color modulation provided by the invention, comprising: for sending 2 ⁿthe transmitting terminal 100 of the light wave of kind of different wave length and for receiving and resolve the receiving terminal 200 of light wave, wherein, N is positive integer.

Wherein, transmitting terminal 100 and receiving terminal 200 adopt color modulation technology to communicate, and the color planisphere in its color modulation technology comprises at least 2 ⁿindividual constellation point.One group of binary data is mapped as a described constellation point, and the light wave of a corresponding a kind of wavelength of described constellation point.

In the present embodiment, transmitting terminal 100 specifically for, generate one group of binary data, and obtain the constellation point corresponding with binary data according to color planisphere, drive the light wave that generates the wavelength corresponding with constellation point.

Particularly, transmitting terminal 100 comprises: signal source module 101, mapping block 102, driver module 103 and light source module 104.Wherein,

Signal source module 101, for generating binary data.

In the present invention, signal source module 101 generates binary data.

Mapping block 102, for binary data being mapped to the constellation point on color planisphere, to obtain the constellation point corresponding with described binary data.

In the present embodiment, color planisphere comprises at least 2 ⁿindividual constellation point, wherein, a corresponding one group of binary data of constellation point.When signal source module 101 generates after one group of binary data, mapping block 103 can, according to color planisphere, be mapped to the constellation point on color planisphere by binary data, to obtain the constellation point corresponding with described binary data.

Driver module 103, for according to described constellation point, drives light wave light source 104 to generate the light wave of the wavelength corresponding with described constellation point.

Light source module 104, for generating and sending the light wave of different wave length.

In the present embodiment, light source module 104 can comprise following two kinds of implementations:

(1), light source module 104 comprises 2 ⁿthe LED (Light-Emitting Diode, light-emitting diode) of individual different colours.Wherein, a constellation point on a LED corresponding color planisphere.

In the present invention, comprise multiple LED.Wherein, each LED generates a kind of light wave of color.Therefore, when trigger on color planisphere certain constellation point time, drive LED corresponding to this constellation point luminous, generate and send the light wave with this LED corresponding color.

Now, driver module 103 specifically for, drive the LED corresponding with constellation point to generate a kind of light wave of color according to constellation point, thus the light wave of the generation wavelength corresponding with constellation point; Wherein, the light wave of a corresponding a kind of color of LED.

(2), light source module 104 comprises that one can generate 2 ⁿplant the LED of the light wave of different wave length.Wherein, a corresponding a kind of wavelength of constellation point.

In the present invention, only include a LED.But this LED can send 2 ⁿthe light wave of planting different colours, can generate 2 ⁿplant the light wave of different wave length.When trigger on color planisphere certain constellation point time, drive the LED of wavelength corresponding to this constellation point luminous, generate and send the light wave with this LED corresponding color.

Now, driver module 103 specifically for, according to constellation point drive can generate 2 ⁿthe LED that plants the light wave of different wave length generates the light wave of the wavelength corresponding with described constellation point.

Receiving terminal 200 specifically for, receive and resolve light wave, to obtain the constellation point corresponding with the wavelength of light wave, and then obtain the binary data corresponding with constellation point according to color planisphere.

Particularly, receiving terminal 200 comprises: photodiode PD detection module 201, wavelength determination module 202 are conciliate mapping block 203.Wherein,

Photodiode PD detection module 201, for receiving after the light wave that transmitting terminal 100 sends, formation voltage value.

Wherein, photodiode PD detection module 201 comprises PD and corresponding testing circuit.The response sensitivity of its PD changes with the variation of optical wavelength.

Wavelength determination module 202, for the magnitude of voltage generating according to PD detection module 201, determines the wavelength of the light wave that magnitude of voltage is corresponding.

Demapping module 203, obtain the constellation point corresponding with wavelength, and then according to color planisphere, demapping goes out binary data corresponding with constellation point on color planisphere for the wavelength of the light wave according to definite.

Specifically introducing before the implementation procedure of receiving terminal 200 of the present invention, first inventor needs some prior aries to be introduced.

According to the spectral response characteristic of PD, the response sensitivity of PD can change with the variation of wavelength.As shown in Figure 3 and Figure 4, the schematic diagram that its response sensitivity that shows respectively SD445-14-21-305 model PD and S5972 model PD changes with optical wavelength.Wherein, abscissa is optical wavelength, the response sensitivity that ordinate is PD.From Fig. 3, Fig. 4, can be easy to learn, the response sensitivity of PD is not changeless, taking Fig. 3 as example, the response sensitivity of PD is before optical wavelength is less than 950nm, along with the increase of optical wavelength increases, in the time that optical wavelength reaches 950nm, the response sensitivity of PD reaches maximum, subsequently along with the response sensitivity of the increase PD of optical wavelength reduces gradually.The present invention has utilized the response sensitivity of PD to change this characteristic changing with optical wavelength just.

The DC current gain expression formula that further, can obtain optical channel according to lambert's radiation model of LED is:

$H_{i,j}=\left\{\begin{array}{cc}\frac{(m+1)\mathrm{A\γ}}{2\mathrm{\π}{D}_{\mathrm{ij}}^2}{\cos }^m\left(\mathrm{\φ}\right)T\left(\mathrm{\ψ}\right)g\left(\mathrm{\ψ}\right)\cos \left(\mathrm{\ψ}\right)& 0\≤\mathrm{\ψ}\≤{\mathrm{\ψ}}_c\\ 0& \mathrm{\ψ}>{\mathrm{\ψ}}_c\end{array}\right.$

Wherein, m is the luminous exponent number of LED, depends on the half-power angle of LED particularly, a is the physical area of PD detector, and γ is the detection sensitivity of PD, D _ijbe j transmitting terminal to the distance between i receiving terminal, φ is the light emitting anger of LED, ψ is receiving terminal angle of incidence of light, T (ψ) is the gain of optical filter, ψ _cbe the angle of visual field of receiver, g (ψ) is the gain of concentrator.Wherein, the expression formula of g (ψ) is:

$g\left(\mathrm{\ψ}\right)=\left\{\begin{array}{cc}\frac{n^2}{{\sin }^2{\mathrm{\ψ}}_c},& 0\≤\mathrm{\ψ}\≤\mathrm{\ψ}\\ 0,& \mathrm{\ψ}>{\mathrm{\ψ}}_c\end{array}\right.$

Wherein, n represents the refraction coefficient of concentrator.

Therefore, from the DC current gain expression formula of above-mentioned optical channel, can learn, the response sensitivity γ difference of PD will produce different channel DC current gain.And the basis that the difference of this channel DC current gain can detect at receiving terminal just.

Therefore, the present invention changes the characteristic changing with optical wavelength according to the response sensitivity of PD, has realized the measuring ability of receiving terminal 200.

Lower mask body is introduced the implementation procedure of receiving terminal 200 of the present invention.

In the present invention, receiving terminal 100 sends after light wave, is received by the PD detection module 201 in receiving terminal 200.Known according to the response sensitivity characteristic of PD, for the light wave of different wave length, PD detection module 201 produces the voltage of different stage after intensity detection, generates the magnitude of voltage corresponding with light wave.And then the magnitude of voltage that wavelength determination module 202 generates according to PD detection module 201, determines the wavelength of the light wave that magnitude of voltage is corresponding.

In the present invention, the light wave of the corresponding a kind of wavelength of a constellation point on color planisphere.And one group of binary data is mapped as a constellation point.Therefore, demapping module 203 obtains according to the wavelength of definite light wave the constellation point that described wavelength is corresponding, and then according to color planisphere, demapping goes out binary data corresponding with constellation point on color planisphere, i.e. the present invention has demodulated the data that transmitting terminal 100 sends.

It should be noted that, the present invention, in the time of design colours planisphere, make full use of the dynamic range of the response sensitivity of PD, and the visible-range interior focusing wave-wave progress row between maximum and the minimum value of the response sensitivity of PD distributes.

Application technique scheme, a kind of visible light communication system based on color modulation provided by the invention comprises for sending 2 ⁿthe transmitting terminal 100 of the light wave of kind of different wave length and for receiving and resolve the receiving terminal 200 of light wave, N is positive integer.Wherein, transmitting terminal and receiving terminal adopt color modulation technology to communicate.Particularly, transmitting terminal mapping method and receiving terminal de-mapping method all carry out according to the color planisphere in color modulation technology.Wherein color planisphere comprises at least 2 ⁿindividual constellation point, wherein, one group of binary data is mapped as a described constellation point, and the light wave of a corresponding a kind of wavelength of described constellation point.

Particularly, transmitting terminal 100 generates one group of binary data, and obtains the constellation point corresponding with binary data according to color planisphere, drives the light wave that generates the wavelength corresponding with constellation point, is sent to receiving terminal 200.Receiving terminal 200 receives and resolves described light wave, to obtain the constellation point corresponding with the wavelength of light wave, and then obtains the binary data corresponding with constellation point according to color planisphere.Therefore, the present invention is loaded into information on color gamut, and the light wave that utilizes color modulation technology to make transmitting terminal 100 send different wave length transmits transfer of data to realize.And the band efficiency of the color modulation technology in the present invention is N.

Meanwhile, color modulation technology can realize the high-speed communication of visible ray simply, efficiently, and the extra means such as filter are set without receiving terminal, realizes simple.

It should be noted that, in this article, relational terms such as the first and second grades is only used for an entity or operation to separate with another entity or operating space, and not necessarily requires or imply and between these entities or operation, have the relation of any this reality or sequentially.And, term " comprises ", " comprising " or its any other variant are intended to contain comprising of nonexcludability, thereby the process, method, article or the equipment that make to comprise a series of key elements not only comprise those key elements, but also comprise other key elements of clearly not listing, or be also included as the intrinsic key element of this process, method, article or equipment.The in the situation that of more restrictions not, the key element being limited by statement " comprising ... ", and be not precluded within process, method, article or the equipment that comprises described key element and also have other identical element.

Above a kind of visible light communication method and system based on color modulation provided by the present invention is described in detail, applied specific case herein principle of the present invention and execution mode are set forth, the explanation of above embodiment is just for helping to understand method of the present invention and core concept thereof; , for one of ordinary skill in the art, according to thought of the present invention, all will change in specific embodiments and applications, in sum, this description should not be construed as limitation of the present invention meanwhile.

Claims (4)

1. the visible light communication method based on color modulation, comprises for sending 2 ⁿthe transmitting terminal of the light wave of kind of different wave length and for receiving and resolve the receiving terminal of described light wave, described N is positive integer, it is characterized in that, described transmitting terminal and described receiving terminal adopt color modulation technology to communicate, and the color planisphere in described color modulation technology comprises at least 2 ⁿindividual constellation point, wherein, one group of binary data is mapped as a described constellation point, and the light wave of a corresponding a kind of wavelength of described constellation point; Described method comprises:

Described transmitting terminal generates one group of binary data;

Described binary data is mapped to the constellation point on described color planisphere by described transmitting terminal, to obtain the constellation point corresponding with described binary data;

Described transmitting terminal drives the light wave that generates the wavelength corresponding with described constellation point;

Described receiving terminal receives described light wave, formation voltage value;

Described receiving terminal, according to described magnitude of voltage, is determined the wavelength of the light wave that described magnitude of voltage is corresponding;

Described receiving terminal obtains according to the wavelength of definite light wave the constellation point that described wavelength is corresponding, and then according to described color planisphere, demapping goes out the binary data corresponding with described constellation point on described color planisphere.

2. the visible light communication system based on color modulation, comprises for sending 2 ⁿthe transmitting terminal of the light wave of kind of different wave length and for receiving and resolve the receiving terminal of described light wave, described N is positive integer, it is characterized in that, described transmitting terminal and described receiving terminal adopt color modulation technology to communicate, and the color planisphere in described color modulation technology comprises at least 2 ⁿindividual constellation point, wherein, one group of binary data is mapped as a described constellation point, and the light wave of a corresponding a kind of wavelength of described constellation point; Wherein,

Described transmitting terminal specifically comprises:

Signal source module, for generating binary data;

Mapping block, for described binary data being mapped to the constellation point on described color planisphere, to obtain the constellation point corresponding with described binary data;

Driver module, for the described constellation point of foundation, driving light source module generates the light wave of the wavelength corresponding with described constellation point;

Light source module, for generating and sending the light wave of different wave length;

Described receiving terminal specifically comprises:

Photodiode PD detection module, for receiving after the light wave of described transmitting terminal transmission, formation voltage value;

Wavelength determination module, for the magnitude of voltage generating according to described PD detection module, determines the wavelength of the light wave that described magnitude of voltage is corresponding;

Demapping module, obtains for the wavelength of the light wave according to definite the constellation point that described wavelength is corresponding, and then according to described color planisphere, demapping goes out the binary data corresponding with described constellation point on described color planisphere.

3. system according to claim 2, is characterized in that,

Described light source module comprises 2 ⁿthe LED of individual different colours, wherein, a corresponding a kind of wavelength of described LED;

Described driver module specifically for, drive the LED corresponding with described constellation point to generate a kind of light wave of color according to described constellation point; Or,

Described light source module comprises that one can generate 2 ⁿplant the LED of the light wave of different wave length;

Described driver element specifically for, described in driving according to described constellation point, can generate 2 ⁿthe LED that plants the light wave of different wave length generates the light wave of the wavelength corresponding with described constellation point.

4. system according to claim 2, is characterized in that, described photodiode PD detection module comprises PD and testing circuit; Wherein,

The response sensitivity of described PD changes with the variation of optical wavelength.