CN102811092A - Point-to-point visible light wireless communication system based on white LED devices - Google Patents

Abstract

The invention discloses a point-to-point visible light wireless communication system based on a white light emitting diode (LED) component, which comprises an emitting end and a receiving end, wherein the emitting end comprises an amplifier, a biasing device, an LED power supply and an LED component; the receiving end comprises a photoelectrical detector and a power amplifier. The point-to-point visible light wireless communication system based on the white LED component is free from the electromagnetic interference, thereby realizing the short-distance communication service with great capacity and high speed.

Description

Point-to-point visible light wireless communication system based on white LED devices

technical field

The invention relates to a point-to-point visible light wireless communication system based on a white light LED device, which belongs to the technical field of communication.

Background technique

White LED devices have the advantages of low power consumption, long service life, and environmental protection. Its output optical power and driving current have high response sensitivity and can realize high-speed data communication. Visible light communication (visible light communication VLC) is a wireless optical communication technology based on white light LED devices. Utilizing the high-speed response characteristics of the white light LED device, while the LED light source is illuminating, the output current of the LED device can be modulated at high speed by using the data output module and the biaser, and the information can be sent through the change of the output light intensity.

Visible light wireless communication technology can be integrated with current wireless communication systems. Visible light wireless communication has developed a new spectrum resource of visible light (wavelength 380nm-780nm), which is not affected by complex electromagnetic interference, and can realize ubiquitous communication while lighting. Unlimited visible light spectrum resources can provide large-capacity communication services. , medical monitoring, underwater and mines and other special scenarios have broad application prospects.

Contents of the invention

The technical problem to be solved by the present invention is to provide a point-to-point visible light wireless communication system based on white LED devices that can realize large-capacity, high-speed short-distance communication services without electromagnetic interference.

The present invention adopts the following technical solutions to solve the above technical problems: the present invention designs a point-to-point visible light wireless communication system based on white light LED devices, including a signal acquisition device, a transmitting end, a receiving end and a signal output device, wherein:

The transmitting end includes an amplifier, a bias device, an LED power supply and an LED device, and the receiving end includes a photodetector and a power amplifier;

The signal acquisition device acquires information (sound, video, data, etc.) that the system needs to transmit;

The amplifier receives the signal output by the external signal acquisition device, and performs negative feedback amplification on the signal, and transmits the amplified signal to the bias device;

The biaser receives the DC signal of the LED power supply and the amplified signal, performs coupling processing, and transmits the coupled electrical signal to the LED device;

The LED device converts the electrical signal into an optical signal, and transmits it to the photodetector through wireless transmission;

The photodetector receives the optical signal, converts the optical signal into an electrical signal, and transmits it to the power amplifier;

The power amplifier receives the electrical signal, amplifies the electrical signal and transmits it to an external signal output device.

As an optimized structure of the present invention: the LED device is a blue LED device.

Compared with the prior art, the present invention adopts the above technical scheme and has the following technical effects:

1. The point-to-point visible light wireless communication system based on white LED devices designed in the present invention uses LED devices to transmit information (sound, video, data, etc.), and can realize the integration of lighting and communication;

2. The point-to-point visible light wireless communication system based on white LED devices designed by the present invention uses visible light for information transmission, and does not occupy scarce spectrum resources;

3. The point-to-point visible light wireless communication system based on white light LED devices designed by the present invention uses visible light for information transmission, and can realize high-speed and large-capacity communication services in a short distance;

4. The point-to-point visible light wireless communication system based on white light LED devices designed by the present invention uses visible light for information transmission, and has application technical advantages in special scenarios such as airplanes, airports, mines, hospitals, and underwater.

Description of drawings

Fig. 1 is a transmission schematic diagram of a point-to-point visible light wireless communication system based on a white LED device designed in the present invention;

Fig. 2 is a schematic circuit diagram of an audio transmitting end of a point-to-point visible light wireless communication system based on a white light LED device designed in the present invention;

Fig. 3 is the block diagram of the circuit module of the audio transmission end of the point-to-point visible light wireless communication system based on the white light LED device designed by the present invention;

4 is a schematic circuit diagram of an audio receiving end of a point-to-point visible light wireless communication system based on a white LED device designed in the present invention;

Fig. 5 is a circuit module block diagram of the audio receiving end of the point-to-point visible light wireless communication system based on the white light LED device designed by the present invention;

Fig. 6 is a simulated optical power distribution diagram of the LED transmission signal of the point-to-point visible light wireless communication system based on the white light LED device designed in the present invention.

Detailed ways

Below in conjunction with accompanying drawing, technical scheme of the present invention is described in further detail:

As shown in Figure 1, a point-to-point visible light wireless communication system based on white LED devices includes a signal acquisition device, a transmitter, a receiver and a signal output device, wherein:

The transmitting end includes an amplifier, a bias device, an LED power supply and an LED device, and the receiving end includes a photodetector and a power amplifier;

The signal acquisition device acquires information (sound, video, data, etc.) that the system needs to transmit;

The amplifier receives the signal output by the external signal acquisition device, and performs negative feedback amplification on the signal, and transmits the amplified signal to the bias device;

The biaser receives the DC signal of the LED power supply and the amplified signal, performs coupling processing, and transmits the coupled electrical signal to the LED device;

The LED device converts the electrical signal into an optical signal, and transmits it to the photodetector through wireless transmission;

The photodetector receives the optical signal, converts the optical signal into an electrical signal, and transmits it to the power amplifier;

The power amplifier receives the electrical signal, amplifies the electrical signal and transmits it to an external signal output device.

As shown in Figure 2 and Figure 3, in a specific embodiment, in order to achieve better results, the amplifier includes a triangular wave generating circuit, an amplifying circuit and a comparator, and the bias device includes a DC bias circuit and a voltage stabilizing circuit ;in:

The triangular wave generating circuit generates a triangular wave signal, and the triangular wave signal is transmitted to the comparator after being amplified by the load feedback of the amplifying circuit, and is compared with the input audio signal in the comparator, and the output terminal of the comparator generates a pulse width modulation signal ;

The pulse width modulation signal is coupled through the drive current generated by the biaser and the LED power supply to drive the LED device;

When the LED light source is illuminated, the pulse width modulation signal can affect the driving current of the LED device, thereby modulating the change of the output light intensity of the LED device, and then the optical signal is covered by the light field to realize free-space optical transmission;

As shown in Figure 6, the point-to-point visible light wireless communication system based on white light LED devices designed by the present invention carries information through the spatial coverage of the light field, improves the output power of LED devices, can reduce the impact of environmental noise, and can increase the system The working distance, in a specific embodiment, can realize free-space visible light communication with a communication distance of 2 meters.

As shown in Figure 4 and Figure 5, in a specific embodiment, the photodetector includes a photodiode, a primary amplifier circuit and a secondary amplifier circuit;

The working principle of the receiving end is: the photodetector receives and detects changes in the intensity of the light field, and the generated photocurrent passes through the primary amplifier circuit and the secondary amplifier circuit in turn, and outputs an electrical signal to an external load. The electrical signal changes with the strength of the light field, and is amplified by the power amplifier before being transmitted to the speaker, so that the receiving end completes the collection, conversion and reception of information.

As an optimized structure of the present invention: in a specific embodiment, the LED device is a blue LED device, which can increase the transmission speed of the link.

In a specific embodiment, optical components such as light filtering and light concentrating are used at the receiving end, which can increase the transmission speed of the link and increase the transmission efficiency and capability of the device.

Furthermore, the system realizes the carrying of information through the spatial coverage of the light field, improves the output power of the LED device, can reduce the impact of environmental noise, and can increase the working distance of the system. The proposed system can achieve a communication distance of 2 meters. Free space visible light communication;

Furthermore, the system can integrate visible light sensing system to realize the integration of lighting, communication and sensing.

Claims (2)

1. point-to-point visible light wireless communication system based on white light LED part; Comprise signal pickup assembly, transmitting terminal, receiving terminal and signal output apparatus; It is characterized in that: said transmitting terminal comprises amplifier, biasing device, LED power supply and LED device, and said receiving terminal comprises photodetector and power amplifier;

Said signal pickup assembly obtains system needs information transmitted (sound, video, data etc.);

Said amplifier receives the signal of external signal harvester output, and said signal is carried out negative feedback amplify, and the signal after will amplifying transfers to the biasing device;

Said biasing device receives the direct current signal of LED power supply and the signal after the above-mentioned amplification, and the processing that is coupled, and the signal of telecommunication that will be coupled after handling transfers to the LED device;

Said LED device converts above-said current signal into light signal, and transfers to photodetector through Wireless transmission mode;

Said photodetector receives above-mentioned light signal, and transfers to said power amplifier after converting light signal into the signal of telecommunication;

Said power amplifier receives above-said current signal, and above-said current signal is carried out transferring to external signal output device after the processing and amplifying.

2. the point-to-point visible light wireless communication system based on white light LED part according to claim 1, it is characterized in that: said LED device is selected the blue-ray LED device for use.

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