Design And Realization Of Man Overboard System

In the stage discussion of International Telecommunication Union WP5B's 5th conference, it proposed that assign a dedicated communication channel for MOB (Man Overboard). This paper proceeds from the proposal, integrates the basic requirements of MOB which proposed by IMO (International Maritime Organization), investigates and studies existed methods and products at home and abroad, then integrates reality and makes innovation, which is in order to design better function equipment.Man overboard is a kind of portable equipment which can wear in human body easily and monitor and transmit safety information of wearer. Man overboard system includes a base station, number of repeaters and multiple user terminals. It implements point to multipoint short-range wireless communication by time division multiple access. Base station paging every user terminal sequentially and after an ending mark every user terminal transmits sole identification number to tell base station the wearer's safety status and position information in every 5 seconds, displays every terminal's information in base station at the same time. If there is a member falling into water accidently the terminal triggers will sent this alarm information to base station immediately, then base station will trigger alarm according to the type of information and warn other crew members. Terminal equipment includes the following modules:(1) Control module, selecting STC12C5A16S2 for the main chip, to implement state prompting, information coding and radio frequency mode control. (2) Radio frequency module, using third-generation wireless transceiver chip nRF401, through a common international ISM (Institute, Scientific, medical) frequency band for data transmission. (3) Low-voltage detection module, using the second reset pin of the main chip for external voltage detection, sending alarm information when battery is low voltage. (4) GPS (Global Positioning System) module, receiving data from GPS satellites transmit radio frequency signal and output obtained location and time information to control module through the standard serial.After testing, the system can monitor and display safety status of maritime workers, alarm immediately when someone fell into water, to a certain extent, it can protect the safety of maritime workers. In addition, the equipment can also be extended to the coastal entertainment or travel ships, yachts or fishing vessels at sea, exploration, scientific investigation and other platforms.