CN203261425U - Underwater digital video transmission device based on LED - Google Patents

Abstract

The utility model discloses an underwater digital video propagation device based on LEDs, which belongs to the technical field of wireless communication. The underwater digital video transmission device includes a sending module and a receiving module packaged in a casing. The sending module includes a composite video broadcasting signal generator, a source coder, a channel coder, and a sending end connected in sequence; the sending end includes an amplifier, a biaser, and a blue or green LED. The input terminal of the amplifier is connected to the output terminal of the channel encoder, the output terminal of the amplifier is connected to the first input terminal of the biaser; the second input terminal of the biaser is connected to the DC component, and the output terminal of the biaser is connected to the anode of the LED; the cathode of the LED is grounded; the receiving module Including receiving end, channel decoder, source decoder, composite video broadcast signal video display equipment connected in sequence The underwater digital video transmission device described in the utility model has good transmission performance underwater; avoids high-power laser light source Large size, high cost, high power consumption, not suitable for underwater communication defects.

Description

Underwater digital video transmission device based on LED

technical field

The utility model discloses an underwater digital video propagation device based on LEDs, which belongs to the technical field of wireless communication. the

Background technique

The massive data generated by CVBS (Composite Video Broadcast Signal) imposes unrealistic requirements on storage capacity, transmission bandwidth, processing power and spectrum resource utilization, making digitization difficult to achieve. To this end, compression coding technology is used to discard those things that are not important to human visual images and human auditory sounds, thereby reducing the amount of data stored, transmitted and processed, and improving the utilization of spectrum resources. the

The propagation distance of electromagnetic waves in water is very limited, and only visible light can travel hundreds of meters in water. In 1963, when Dimtley et al. were studying the propagation characteristics of light waves in the ocean, they found that the attenuation of blue-green light in seawater in the 450-550 nanometer band was much smaller than that of other light bands. At present, underwater optical communication mainly uses blue-green light. Green lasers are used for communication, but high-power laser sources are bulky, costly, and consume a lot of power, so they are not suitable for practical applications in underwater communications. the

Utility model content

The technical problem to be solved by the utility model is to provide an underwater digital video broadcasting device based on LEDs in view of the deficiencies of the above-mentioned background technology. the

The utility model adopts following technical scheme for realizing above-mentioned utility model purpose:

An LED-based underwater digital video transmission device, including a transmitting module and a receiving module encapsulated in a casing,

The sending module includes a sequentially connected composite video broadcast signal generator, a source encoder, a channel encoder, and a sending end; the sending end includes an amplifier, a bias device, and a blue or green LED, wherein: the amplifier input The terminal is connected to the output terminal of the channel encoder, the output terminal of the amplifier is connected to the first input terminal of the biaser; the second input terminal of the biaser is connected to the DC component, and the output terminal of the biaser is connected to the anode of the LED; the cathode of the LED is grounded;

The receiving module includes a receiving end, a channel decoder, a source decoder, and a composite video broadcast signal video display device connected in sequence. the

The utility model adopts the above-mentioned technical scheme, and has the following beneficial effects: the underwater digital video transmission device based on the blue light or green LED device described in the utility model has good transmission performance underwater; avoids the large volume of the high-power laser light source , high cost, high power consumption, and not suitable for underwater communication. the

Description of drawings

Figure 1 is a schematic diagram of an LED-based underwater digital video transmission device. the

Fig. 2 is a measurement chart of optical power attenuation of white LEDs and blue LEDs propagating in water in the underwater digital video transmission system based on blue LEDs designed by the utility model. the

Fig. 3 is a measurement chart of optical power attenuation of blue LEDs propagating in water and air in the underwater digital video transmission system based on blue LEDs designed by the utility model. the

Detailed ways

Below in conjunction with accompanying drawing, the technical scheme of utility model is described in detail:

The underwater digital video transmission device based on LED as shown in Figure 1 includes a transmitting module and a receiving module encapsulated in a housing, a composite video broadcast signal generator, a source encoder, a channel encoder, and a transmitting terminal connected in sequence; The receiving module includes a receiving end, a channel decoder, a source decoder, and a composite video broadcast signal video display device connected in sequence. The sending end includes an amplifier, a biaser, and an LED. The input end of the amplifier is connected to the output end of the channel encoder, and the output end is connected to the first input end of the biaser; the second input end of the biaser is connected to the DC component, and the output end is connected to the anode of the LED. ; LED cathode to ground. The LED device is a blue LED or a green LED. the

Both the source coder and the source decoder adopt the MPEG-2 encoding method, and the channel encoder and channel decoder adopt the HDB3 encoding method. the

The source encoder adopting MPEG-2 encoding method encodes the CVBS sent by the CVBS generator, performs real-time digital compression processing on the video signal, and outputs two differential digital signals; the channel encoder adopting HDB3 encoding mode outputs to the source encoder The two data streams at the end are combined to obtain one data stream transmitted in the channel; the amplifier amplifies the data stream output by the channel encoder and uses it as an input of the bias device; the bias device outputs the LED according to the output of the amplifier and the DC component The driving voltage; the photosensitive device in the receiving end converts the light signal from the LED into an electrical signal, and the electrical signal output by the photosensitive device enters the channel decoder after being amplified, and the channel decoder using HDB3 encoding method divides the output signal of the amplifier into For the two data streams, the source decoder using the MPEG-2 encoding method decompresses the two differential digital signals and restores them to obtain CVBS. the

Adopt blue light LED device to constitute the underwater digital video transmission device described in the utility model, compare with the underwater digital video transmission device that white light LED device constitutes: the optical power attenuation measurement figure that white light LED and blue light LED propagate in water is as Fig. 2 Shown; The optical power attenuation measurement diagram of blue light propagating in water and air is shown in Figure 3. It can be seen that the underwater digital video transmission device based on blue LED is better than the underwater video digital video transmission device based on white LED. The principle of using green LED devices to form the underwater digital video transmission device described in the utility model is the same as that of using blue LED devices to form the underwater digital video transmission device described in the utility model, and its optical power attenuation in water or in the air is the same. smaller than white light. the

In summary, the underwater digital video transmission device based on blue or green LED devices described in this utility model has good transmission performance underwater; it avoids the large volume, high cost, and high power consumption of high-power laser light sources. Not suitable for underwater communication flaws. the

Claims (1)

1. An LED-based underwater digital video transmission device, comprising a transmitting module and a receiving module encapsulated in a housing, characterized in that: The sending module includes a sequentially connected composite video broadcast signal generator, a source encoder, a channel encoder, and a sending end, and the sending end includes an amplifier, a bias device, and a blue or green LED, wherein: the amplifier input The terminal is connected to the output terminal of the channel encoder, the output terminal of the amplifier is connected to the first input terminal of the biaser, the second input terminal of the biaser is connected to the DC component, the output terminal of the biaser is connected to the anode of the LED, and the cathode of the LED grounding; The receiving module includes a receiving end, a channel decoder, a source decoder, and a composite video broadcast signal video display device connected in sequence. the

Images