基于USRP的无线触发系统设计

Design of Wireless Trigger System Based on USRP

摘要:

早期的分布式测试系统多是采用基于硬件连接线的触发方式,优点在于安全性高、速度快,适用于各节点设备较为集中的测试系统。为了使分布式测试系统不受制于线缆,同时又能够对范围更大、位置更分散的对象进行测试,提出了使用无线链路实现触发功能的系统方案,设计了一条无线传输链路,包含了从指令信息产生到指令信息接收整个链路中的各个模块,可以支持两种不同的触发模式--定时触发与随机触发,可以实现“一对一”以及“一对所有”场景的信息传输。通过使用基于USRP+LabVIEW的软件无线电对所提系统进行了功能测试与性能评估。功能测试结果表明,该方案可以顺利实现定时触发与随机触发模式下“一对一”和“一对所有”的信息指令传递。性能评估以时延作为评估指标,评估结果表明,在所使用的USRP+LabVIEW的软件无线电条件下,全链路时延为毫秒级,具体数值由链路参数决定。

Abstract:

The early distributed test system mostly adopts the trigger mode based on hardware connection line, which has the advantages of high security and fast speed, and is suitable for the test system with more centralized devices at each node. In order to make the distributed test system free from cables and test objects with a larger range and more dispersed locations, a wireless link based trigger system solution is proposed. A wireless transmission link is designed, including all modules from instruction information generation to its receiving. It can support two different trigger modes -- timing trigger and random trigger, and it can support both “one-to-one” and “one-to-all” instruction transmission. The software radio combination of USRP and LabVIEW is used to verify the functions and performance of the proposed system. Function tests show that, the “one-to-one” and “one-to-all” instruction transmission under timing trigger mode and random trigger mode can be successfully transmitted and received. In the performance evaluation, delay is considered, and the test results show that, the delay over the whole link is around milliseconds under the test environment of software radio combination of USRP+LabVIEW, and the specific delay value relies on the link parameters.