Research Of Self-organization And Self-Recovery System Of Sensing Datas Based On LED Light Communication

LED lighting is no longer strange for people.Because of the power consumption of LEDlighting devicess and the advantages of long life,energy-saving,environmentalprotection,home and abroad Country promote the use of LED lighting to replace traditionallighting.People use more LED lighting devicess in the interior.It will be able to solve thethree problems in current network,if LED lighting can communicate with another LEDlighting devicess.The three problems are as follows.First,since the bad penetrating of LED light,indoor signal is not easy to divuglee.LED visible light communication for secure transmission of data can be said is the preferred.Secound,because LED visible light communicate without radiation,so there is noradiation damage for humans when visible light is communicating.Third,for LED lighting devices,internet users does not require the complex cablelaying,just need LED base station lights.Internet users can connect to Internet through theLED base station.Using the power lines and signal lines laying in the same line program willreduc the cost for Communications operators,Japan has begun to use this program.Based on this background,in this study author want to solv abig flaw in the current LEDcommunication study—LED network protocol.Envisaged by the author,LED visibleequipmen will be designed more portable in the future,so the study of network protocolbecome more necessary.The research topics proposed in this study is the sudy of ad hoc networks based on LEDvisible light sensor data recovery system.Since author focuses on design for ad hocnetwork,the transmission rate of LED communication devices can only meet Sensor datatransmission.The maximum transfer rate is150bps.Communication distance is30cm-50cm.Bit error rate is2%-3%.Why did author choose to ad hoc networks?The main reason is because here is stillblank.Home and abroad most study on point to point protocol and broadcastiong protocol.Author will port ad hoc protocol into the linux operating system kernel for LEDcommunication devices and will also provide the network device driver of LED device.As long as the user update the operating system,LED communication device will be able tonormal use and the communication between device without the LED base station lights willcommunication by themselves.This will improve the portability of LED communicationdevices.In order to successfully transplant ad hoc protocol,author design a convergencelayer,network protocol and application layer,device driver layer.At the same time,authorcomplete Demand routing method in the device driver layer.In order to solve the stability of the optical communications,author must seriously design the software of the optical communication devices.The software design includes thefollowing three aspects.1. The serial port communication between Microcontroller and SS3C2440development board.2. The Manchester way enconde or conde the pulse sequence3. Timer software design ith fault tolerance mechanisms and recovery mechanismsIn order to test the feasibility of ad hoc protocol for LED device,author set up a VLCsystem.This system doesn`t installation LED base station lights.In order to test the dataexchange of the Internet and Internet of Things,author set up a broadcasting system.Thissystem installation LED base station lights.Users through a web browser to visit the webserver and remote access the broadcasting system communication unit.