Research On Optical Fiber Data Transmission System In Airport Runway Condition Monitoring

Airport runway safety is a top priority to protect the aircraft take-off and landing. Currently, many foreign countries have been engaged in developing foreign object detection (FOD) systems for airport runway. However, the research in china is only at initial stage, with various issues to be explored. Therefore, the development of the runway condition monitoring data transmission system from the perspective of data protection has great practical significance.In this paper, the author proposes a fiber optic data communication scheme based on optical time division multiplexing (OTDM) technology. The scheme utilizes optical fiber communication system, which has the characteristics of high bandwidth, strong anti-jamming capability and low loss, to transmit digital signals. Meanwhile, the method can also ensure the communication demand of the airport runway condition monitoring communication system.Firstly, based on the time-division multiplexing principle, the author has designed the basic frame structure of the system data. Compared to traditional OTDM system, the transmission signal of the proposed scheme requires sequence control in the electrical domain, and then it is converted into the optical domain for multiplexing and transmission. At the receiver side, the system needs to recovery optical clock. The de-multiplexing of transmission signal is conducted in electrical domain.Secondly, the author has designed four basic modules including synchronous clock recovery, data multiplexing, data de-multiplexing and protocol processing. Among them, the synchronous clock recovery module is used to detect the input data’s synchronous symbol and restore the system reference clock. The frame count and the bit count can be obtained by the counter of the data multiplexing module. Meanwhile, the data multiplexing module can locate the allocation of data slots in order to add guard interval in different time slot. The data de-multiplexing module also uses the frame count and the bit count to locate the allocation of data slots, and then utilizes serial-parallel converter module to output the data slots. The protocol processing module deals with the protocol between master and terminal for clock synchronization.Finally, the author has successfully completed the design of core module of host and terminal according to the working principle of the four basic modules. A monitoring port has been built by combining host with PC. The author has also done experiments to gather video data through terminal, which has verified the feasibility of the system scheme.