Design And Research Of Man Overboard Alarm Device Based On Beidou Positioning System

China’s total length of coastline is about32,000kilometers, and mainland coastlineis more than18,000kilometers, and maritime traffic owns some characteristics such ashigh traffic, high density, large range of navigation, complex navigation environmentand so on. Along with the development of China’s economy in recent years, furtherdevelopment and utilization of marine resources is necessary, more and more marinestaff are involving in marine industry such as: fisheries aquaculture, offshore oil and gasresources, marine transportation, marine tourism and so on. At the same time, naturaldisasters or accidents often occur at sea, resulting in a persistently high death toll on thesea. Marine environment is complex and changeable, features of shipwreck accidents’happening are abrupt and catastrophic, it seriously threatens the safety of lives andproperty on the water, comparing equipment development of water safety and rescue inchina with developed countries, it still has a large gap, and distress relief effort facesenormous challenges.Rescue at sea is the last defense line to protect the safety of lives and property atsea, aiding people timely in distress at sea can effectively increases the chances ofsurvival. Positioning in distress at sea is a prerequisite for success of search and rescuefor maritime distress, satellite technology can be applied to rescue personnel inmaritime distress at sea. To solves the inconvenience problem of maritime rescue forworkers in distress, combined with practical, a kind of alarm location systems for thedrowning of persons in distress based on second generation Beidou satellite navigationsystem is developed safety information of marine works is sent to nearby rescue shipsor offshore platforms by wireless transmission module at sea. Once the search andrescue person received the alarm information, they can go rescuing.Alarm positioning system Drowning persons in distress is comprised of two parts:user alarm terminal and rescue terminal in distress. The user handheld terminal uses the UM220module to realize the Beidou satellite positioning, wireless RF chip CC1101realize monitoring the user the current safety status and data transmission, thecondensation sensor HDS10is used to realize automatic alarm function in water. Therescue terminal mainly completes the function of distress alerting and display, the radiofrequency chip CC1101is used to receive and transmit the user data, it is connectedthrough the RS-232C interface with the host computer, after receiving the user distressalarm information, and the whistle alarm is working to remind the rescuer quicklyorganizing the rescue. The rescue terminal is only one, but the handheld terminal canhave multiple. Diagram of water alarm system is designed by Protel DXP software, anddesign the PCB in accordance with the principle of layout PCB and wiring. The alarmsystem uses C language to design, wireless of system communication based on TDMAuses multiple access communication mechanism, the rescue terminal is the host, eachhandheld terminal is the driven machine, the system is set up5seconds as a cycle ofstate information acquisition, host works as the sending command mode in time, eachhandheld terminal is assigned1time periods to communicate with the host.In the test when the man overboard happens or be in danger emergency, alarmdevice can alarm in time, the rescue terminal receives the alarm information and staffpositions, rescuer can quickly organized the rescue. System can complete the task indistress alarm to solve the rescue inconvenience of marine staff distress in a certainextent.