Study Of Distributed Real-time Communication System Of Photoelectric Theodolite Based On Gigabit Ethernet

Photoelectric measurement&control system is allimportant measuring system for shooting range, developed and applied after being 50’s in 20 centuries. Photoelectric theodolite is very important equipment in aviation, aerospace and weapon measuring system, accurately acquires flight track and flight carriage of inflight target through optical photograph, visible/infrared tracking measurement, laser/radar measurement etc, advantage in accurately measure, real-time track, good view (can record target image), strong anti-jamming etc. Generally, need to organize several photoelectric theodolites, guiding radar and ballistic camera etc, constitute, work cooperating to complete measure mission. Along with the development of Ethernet, integrate photoelectric theodolites and its assistance equipments into an advanced and reasonable photoelectric measurement&control system through Ethernet, is the next development point and direction. Currently, most of the photoelectric measurement&control systems still use the traditional and simple mode connecting each other through the experiment network of range. This thesis discusses the application of Ethernet in photoelectric measurement&control system from the angle of network architecture.Firstly, the research background and significance of this thesis are elaborated, the development of photoelectric measurement&control system and Ethernet are summarized, the domestic and outside research status of networked photoelectric measurement&control system are generalized. Then, we research in communicate delay constituent, delay determinately analyze, real-time analyze, network topology design, scheduling algorithm, software hardware realization etc.The architecture and work principle of traditional Ethernet and switched Ethernet are discussed, the communicate delay constituent of switched Ethernet are researched, all parts of delay are made qualitative analysis, the main factor for influencing system delay are elicited. The maximum communicate delay of switched Ethernet is researched, and the maximum delay mathematic expression is derived.Network calculus is adopted to determinately analyze the delay of photoelectric measurement&control system based on switched Ethernet. According to the communicate characteristics of photoelectric measurement&control system, the topology and communicate model of photoelectric measurement&control system are built up, the service curves of communicate system for stream are calculated through the theory of service curve, finally, the precise parse expression of system service curve, delay, buffer size are derived, and can also analyze the carrying capacity of network load under the situation satisfying stream performance.According to the different request of different data of photoelectric measurement&control system, the data is classified for different priority, real-time scheduling algorithm is proposed. Schedule the queue when multiple packets are sent to one destination in switch. Reduce the delay of higher real-time packets, satisfy the request of real-time packets; advance the real-time capability of whole system.Network simulation is a valid method for network protocol analyzes and network architecture design. The OPNET is one of the network simulation software. This thesis adoption OPNET carried on to set up a mold and imitate to the system that we study really, introduced OPNET development condition, introduced the method to set up a mold and give the simulation results.The theories and methods in this thesis are simulated and experimented, proposed a universal design and implementation program for embedded devices Gigabit Ethernet interface and a real-time serial server was designed, resolve the network interface connecting problem of photoelectric measurement&control system; Designed communication protocol, developed image transfer module of photoelectric measurement&control system, a software is designed to acquire image data through Gigabit Ethernet. Photoelectric measurement&control system based on Gigabit Ethernet can be realized via the above-mentioned hardware platform.