Field Monitoring Terminal Anti-interference Technology And Data Processing Algorithms

With the rapid development of modern communication technology, more and more electronic products are developed and gradually known to us, ranging from personal communication equipment to monitoring terminals in military affairs and national defense. Subsequently, monitoring terminals which flexibly combine Geographic Information System, Remote Sensing System, Communication System and Global Positioning System have great technological advantages in various surveying and mapping aspects. So they can be widely used in geological exploration, transportation construction, navigation and so on.This thesis mainly studies field monitoring terminal designed basing on the 4S integration system, which can be used to build early warning system, and thus to monitor areas that are prone to geological disaster. As the complexity of the external environment, the difference in the production process and the quality of the written code can affect field monitoring terminal, it is particular important to reduce interference in design. On the one hand, we reserve some noise temperature for the system design, basing on the analysis of the average noise in external environment. On the other hand, we can enhance the field monitoring terminal’s anti-interference ability through hardware design and software design, that is, to shield interference sources and reduce the cross interference in hardware and to control temperature and monitor watchdog in software.As for data processing three aspects are taken into consideration. The first is about data reception. We analyze the characteristics of the demanded data, get familiar with the framework of the protocol header and use cyclic redundancy code to check the received data and to detect errors. The second is about data storage. Because the storage space is limited, in order not to lose data’s circulating storage, we use a fixed buffer and a dynamic buffer and make them cooperate flexibly to reduce packet loss. The last one is about data transmission. According to the characteristics of TCP protocol, we use TCP Vegas algorithm to reduce network jam. Then, basing on the intrinsic parameter’s characteristics in field monitoring terminal we put forward an enhanced TCP Vegas algorithm so as to further reduce network jam and make sure the data continuity.To sum up, this thesis combines the anti-interference design and data processing methods to make the data sent from field monitoring terminal to center server better meet solution requirements.