Data Acquisition SystemA data acquisition system is an
embedded system dedicated for
data storage and processing. A data acquisition system acquires, stores, process and transfers the data to another system. Overall a data acquisition system performs three tasks: Recording, processing and visualization.
Recording involves the storage of acquired data for later uses. Processing means to translate the data so that it can be transferred to other systems such as analogue to digital or digital to analogue conversion. Visualization involves displaying the processed data on other systems such as temperature graphs, or GPS data on a map. Special software is used for visualization.
DAQ Applications
DAQ cards available in the market to get Data Acquisition functions. DAQ card can be added to single PC, but usually DAQs are used for mission critical and voluminous applications. Such applications include aircraft traffic control, weather forecasting, missile launches, Networks,
industrial applications, etc. DAQs used in such applications are known as distributed data acquisition systems. Distributed data acquisition systems are based on number of sensors, processors or controllers. For example testing a rocket involves number of critical issues such as air pressure, temperature, or radiations. DAQ system used with such applications records these parameters and converts them to electrical signals by itself. This allows not only feasibility in studying and displaying the information but also saves time.
DAQ Implementation
Implementation of high-speed distributed data acquisition system involves lots of
technology issues. Such issues include number of sensors, sensor speed, data- rates, real-time processing, processor technology and processor functionalities, distributed area, storage area, inputs, outputs,
serial/parallel ports and high throughput with a high reliability. Moreover the DAQ systems should be flexible to accommodate advanced and latest technologies.
DAQ Software
Data acquisition systems are mostly used in event driven applications. The information acquired from the sensors can be processed in number of ways. Either a user can process the information or application
software. From user's point of view it takes lots of time to find out the events and calculate respective parameters. So application software is developed according to the specified events. The software can be programmed in such a way that it can automatically record or process or even reject the unnecessary data.
