Implementation Of Multi-task In Radar Receiver/Transmitter Module Automatic Test System Based On LabWindows/CVI

Automatic testing system(ATS) is a rational combination of test instruments, test software and the tested objects wherein the test software is the core part of it which plays an import role in scheduling test instruments and data processing. With the development of electronic science and technology, the tested objects become increasingly complex, the accuracy and real-time requirements are also increasing, which puts forward higher efficiency to test system.In order to improve the test efficiency and real-time attribute of the test system, this paper proposed a software architecture design of multi-task concurrency, focusing on how to regard different test items as independent tasks so that they can be executed in different system threads in concurrent way. On this basis, this paper also discussed that how to split the time-consuming process, such as an external device I/O, from a test task so that system performance can be improved by taking full advantage of the running time coincidence of concurrent threads under multi-core environment. But, at the same time of using this architecture, the multi-task concurrent mode also brings the following problem for system which need be handled:(1) Because of the test instruments in system are shared by all task and limited on amount, and a test task often requires multiple instruments to work together to complete task so that a executing task may be broken by the uncertain execution order of other threads when many task run in a parallel way. At the same time, an unreasonable order of resources competition may also lead to deadlock between threads, which make these tests could not be continued. To solve these problems above, this paper proposed a solution that combining thread-lock and fixed order of occupying resource.(2) In multi-thread application, there are multiple worker threads work together, sharing information between each thread is the basis for their collaboration. In order to ensure the effectiveness and safety of test data exchange between threads, this paper proposed a way of information sharing which using shared data area as a communication medium between the threads with thread-lock and status identifiers.(3) The system contains a number of test tasks, frequent creation and destruction of threads will largely affect the efficiency of the program when they execute in multi-task concurrency way. To solve this problem, this paper presented thread pool based on LabWindows/CVI to achieve a thread resource reuse, which reduced the performance loss caused by thread creation and destruction process.(4) Because these test items in module may be coupling within test process, to remove redundant test process and improve test efficiency, exerting the advantages of concurrent execution of multiple tasks mostly, the execution order of tasks need a reasonable adjustment. In this paper, we proposed an automatic adjustment algorithm of test order based on topological sorting which improved system performance and reduced operational complexity for testers.