Research On Data Processing And Transmission Based On Virtual Instrumentation

The emergence of virtual instrumentation has set off a fresh wave in the testing field. With the complexity of tasks in testing systems, people have put forward higher requirement for the data processing and transmission technology. Along with the rapid development of micro-electronics and computer sciences, NI has developed the virtual instrument platform LabVIEW based on multi-bus system, which can build different complexity of virtual instrument in the automatic testing systemIn this paper , combining with the the current research of virtual instrument technology, the research meaning of networked measurement and control system based on virtual instrument is introduced, the design of a remote data processing and transmission system based on virtual instrumentation is discussed. Firstly, the system error which emerge in the course of data acquisition is analyzed, then the least-squares curve fitting algorithm for system error compensation is used, and this approach makes the measured data satisfied to system accuracy. Several common data compression algorithm are analyzed and compared in this article, especially LZW data compression algorithm, then, an improved method combined with the characteristics of measurement data is proposed, which makes the compression ratio reduced by 5% compared with the original LZW algorithm. Then the ARINC429 bus is introduced, which is widely applied to the field of aviation and aerospace at present. The theory of the error control technology is studied, and the network delay in switch ethernet when there are huge volume of data need to transfer is mainly analyzed. On this basis, the paper designs a testing system which corresponds to the actual engineering requirement, and presents the architecture. This paper adopts the idea of modularization design by making use of the functions of the LabVIEW. A set of virtual instrument measurement system has been designed for collecting and analysing the measured data , and each module are detailed. Local-based data acquisition and processing, reliable data transmission and remote control functions are implemented on the basis of ARINC429 bus and Ethernet technology , and finally applied to a type of integrated Test and Control System.