Data Acquisition and Signal Processing for Smart Sensors

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SMART SENSORS FOR ELECTRICAL AND NON-ELECTRICAL, PHYSICAL AND CHEMICAL VARIABLES: TENDENCIES AND PERSPECTIVES

The processing and interpretation of information arriving from the outside are the main tasks of data acquisition systems and measuring instruments based on computers. Data acquisition and control systems need to get real-world signals into the computer. These signals come from a diverse range of transducers and sensors. According to [7] ‘Data Acquisition (DAQ) is collecting and measuring electrical signals from sensors and transducers and inputting them to a computer for processing.’ Further processing can include the sensors' characteristic transformation, joint processing for many parameters as well as statistical calculation of results and presenting them in a user-friendly manner.

According to the output signal, sensors and transducers can be divided into potential (amplitude), current, frequency, pulse-time and code. As a result, the task of adequate sensor interfacing with PCs arises before the developers and users of any data acquisition systems. Therefore special attention must be paid to the problems of output conversion into a digital format as well as to high accuracy and speed conversion methods.

In general, a sensor is a device, which is designed to acquire information from an object and transform it into an electrical signal. A classical integrated sensor can be divided into four parts as shown in Figure 1.1. The first block is a sensing element (for example, ...