Voice broadcast system based on visible light communication

Abstract

The invention discloses a voice broadcast system based on visible light communication. The voice broadcast system based on the visible light communication comprises a visible light emitter and a fixed terminal comprising a photodiode, wherein the fixed terminal is connected with the visible light emitter in a wireless visible light communication mode; the visible light emitter comprises an AD (analog / digital) converter, a parallel-series data conversion module, an LED (light emitting diode) and an LED driving circuit, and the parallel-series data conversion module comprising a first FPGA (field programmable gate array) processer; the fixed terminal comprises a photoelectric receiver, a parallel-series data conversion module, a DA (data / analog) converter and a loudspeaker box and the parallel-series data conversion module comprises a second FPGA processor. The voice broadcast system based on the visible light communication achieves a voice signal wireless communication function through lighting visible light, can be applied to voice information broadcasting in places requiring all-weather lighting such as superstores and subway stations as well as radio broadcasting in places requiring secure communication such as examination rooms, and is convenient to mount and maintain, wide in usage range, energy-saving, environmentally friendly, scientific, reasonable, safe and reliable.

Description

technical field [0001] The invention relates to a voice broadcast system based on visible light communication, which belongs to the field of multimedia information transmission and playback. Background technique [0002] In recent years, semiconductor (LED) lighting technology known as "green lighting" has developed rapidly, especially white LEDs are attracting more people's attention, and they are considered to be the next generation of lighting sources. It will eventually replace incandescent and fluorescent light bulbs that are widely used in offices and homes today. Utilizing the high-speed light-emitting response characteristics of LEDs, the signal is modulated to the visible light of LEDs for transmission, which can realize the high-efficiency mode of lighting and communication integration. [0003] Sound broadcasting is usually used in stations, shopping malls, public venues, buildings, and residential areas for background music broadcasting, paging broadcasting, and...

AI Technical Summary

Problems solved by technology

However, the traditional wired sound broadcasting system has the following disadvantages: First, the transmission line needs to be specially laid, and it is easy to generate parasitic capacitance to affect the system performance. problems such as gnawing, etc., increase the system maintenance cost; secondly, the wired transmission makes the speaker layout fixed and inflexible, and the sound broadcasting effect is difficult to guarantee; thirdly, the sound broadcasting of the wired transmission cannot be used in occasions with strict restrictions on electromagnetic interference; Finally, the traditional cable broadcasting system still has problems such as difficult wiring, complicated installation, poor expansion, and damage to the wall.

[0005] The wireless broadcasting system used to play listening test questions uses radio waves to transmit sound signals. It has the characteristics of no need for poles, wide coverage, unlimited expansion, convenient installation and maintenance, low investment, and beautiful and clear sound quality. However, the traditional wireless The broadcasting system has the following disadvantages: First, the traditional wireless broadcasting system cannot be used in occasions with strict restrictions on electromagnetic interference; secondly, the sound signal transmitted by the traditional wireless broadcasting system is easy to be monitored, causing problems such as leakage of test questions and cheating in the exam.

[0006] The visible light voice communication system that has emerged in recent years is still in its immature stage. The main problems are: the use of complex modulation and demodulation technology increases the cost of system implementation and maintenance; the transmission speed is low and the distance is short. In order to avoid the obvious flickering of LED lights, Technologies such as Macchester coding must be used, which also increases the complexity of the system

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