基于DSP的VXI高速高精度数据采集技术研究

【作者】 孙阳；

【导师】 余锋； 汪乐宇；

【作者基本信息】 浙江大学 ， 仪器科学与技术， 2003， 硕士

【摘要】 VXI总线测试平台是仪器测量领域的前沿技术，可以灵活地组建自动测试系统，其模块化、灵活性强、即插即用、数字吞吐能力强的特点使VXI总线测试平台的应用越来越广泛。本文设计的高速高精度数据采集系统是基于VXI总线的自动测量模块。 对于高速数据采集与处理，随着数据量的不断加大和实时处理要求的不断提高，人们提出了用DSP进行数据处理，以便提高系统的实时性，并减小对数据传输速度和存储容量的压力。DSP高度优化的结构使它能快速响应I／O的变化，并进行高速数据传输。因此，基于DSP的高速高精度数据采集模块已成为VXI自动测试系统的基本模块之一。 文中首先介绍了一种模块化的VXI仪器平台VVP(VXI Versatile Plug-in)。VVP系统是一种寄存器基、C尺寸、单槽位的32位VXI仪器，它采用主板+插板的构架，具体功能分散在若干插板上形成应用子系统，每个主板最多支持4块插板。主板采用32位浮点DSP做VXI模块的主板控制器，利用其高度优化的处理器结构和独特的指令系统，对数据采集进行高效实时的控制、分析与处理。 高速高精度数据采集模块是在VVP仪器平台上开发出来的。该模块作为一块VVP仪器平台上的插板，采用20MSPS的16位A／D转换器，一块插板上设计了2个高速A／D转换通道，每个通道有4K×16位的缓冲存储器，可以内部触发、外部触发和软件触发。VVP仪器平台最多可以支持4块插板8路A／D同时工作。 VXI仪器没有传统仪器的操作和显示面板，对VXI仪器的操作与显示是借助上位计算机来实现的，用户与仪器的交互界面也变为了由计算机软件实现的软面板，虚拟仪器的软面板以图形化的界面与用户交互，大大方便了用户熟悉和操作仪器。对于本采集系统我们提供了功能强大的软面板，利用软面板可用交互的方式控制VXI仪器，DSP程序可以灵活方便地从上位机下载。 最后，文中给出了高速高精度数据采集模块的测试结果和结论。更多还原

【Abstract】 The VXI-bus based test platform is the leading technology in the field of instrument testing,it can easily make up the automatic testing system. VXI-bus’s modulation,flexibility,plug & play and high data throughput make it widely used in the industrial society. This paper presents a high speed and high precision data sampling system based on the VXI-bus.Due to the high data throughput and the need of real-time digital signal processing in high-speed data sampling system,we proposed to use DSP to do real-time signal processing to minimize the rate of data transferring and reduce memory size. The high performance of DSP can quickly respond to high speed I/O. Now,DSP based high-speed data sampling system has become a basic module in VXI automatic testing system.In this paper,we proposed a VXI Versatile Plug-in (WP) instrument platform. The VXI Versatile Plug-in (VVP) platform is a register-based,C-size,32-bit and single slot instrument. A complete VVP instrument consists of one enhanced main board and four plug-in boards,which is suitable for constructing basic instruments. The main board uses a 32-bits floating point DSP to do the real-time control and digital signal processing.Based on the VVP platform,our team has developed a high speed and high precision data sampling module. As a plug-in board in VVP,it uses a 20Mhz 16-bit A/D converter to sample analog signals. It contains two A/D channels,every channel has a 4KX 16bit buffer. It has three flexible trigger modes:inner trig,outer trig and software trig. VVP platform can support up to 4 plug-in boards (8 channel A/D) to work together.VXI instrument doesn’t have the traditional instrument panel,we can control the VXI instrument by the computer. Computer soft panel realizes the interaction between users and instrument. The soft panel interacts with the users by a graphic interface.which helps the users to be familiar with and operate the instrument in a short period of time. In this sampling system,we provide a powerful soft panel that can easily control the VXI instrument.Finally,some testing data and conclusion is given.更多还原