Data acquisition is the process of extracting, transforming, and transporting data from the source systems and external data sources to the data processing system to be displayed, analyzed, and stored. A data acquisition system (DAQ) typically consist of transducers for asserting and measuring electrical signals, signal conditioning logic to perform amplification, isolation, and filtering, and other hardware for receiving analog signals and providing them to a processing system, such as a personal computer. Data acquisition systems are used to perform a variety of functions, including laboratory research, process monitoring and control, data logging, analytical chemistry, tests and analysis of physical phenomena, and control of mechanical or electrical machinery. Data recorders are used in a wide variety of applications for imprinting various types of forms, and documents. Data collection systems or data loggers generally include memory chips or strip charts for electronic recording, probes or sensors which measure product environmental parameters and are connected to the data logger. Hand-held portable data collection systems permit in field data collection for up-to-date information processing.
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Monday, 18 December 2006 |
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A data recorder refers to any electronic, electro-mechanical, or electro-chemical apparatus that utilize sensor-based technologies for measuring and tracking the relevant data over time, including both storing such data for later reading and enabling real-time access to the data. Data recorders are used to monitor, record and analyze process and equipment behavior in many process, manufacturing, research, and utility applications. Commercial aircraft employ data recorders to aid in the accident reconstruction and diagnostic process. In electrical utilities, data recorders monitor electrical power lines for signal fluctuations indicative of problems in the transmission line. Data recorders are ultimately utilized to store data so that such data may be accessed and analyzed at a later time. |
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Wednesday, 13 December 2006 |
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Wireless telemetry systems are remote communication systems by which measurements are made or other data collected at remote or inaccessible points, and transmitted using wireless radio transmission. Telemetry systems are used for remote data monitoring in a variety of different applications. Telemetry devices typically transmit data on a timed basis or on the occurrence of an event, such as a pulse received from the meter being read. Telemetry systems for implantable medical devices use radio frequency (RF) energy to enable bidirectional communication between the implantable medical device and an external programmer. The drilling of oil and gas wells typically involves the use of telemetry systems to provide data regarding the subsurface formation penetrated by a borehole. |
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Wednesday, 06 December 2006 |
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Digital-to-analog converters (DACs) serve to convert a digital input code into the corresponding analog output voltage. A current mode DAC generates a differential current output that is typically applied to a current-to-voltage converting amplifier to produce a differential voltage output. A high resolution, high speed DAC may find applications in cellular base stations, wireless communications, direct digital frequency synthesis, signal reconstruction, test equipment, high resolution imaging systems and arbitrary waveform generators. A DAC is an important component for processing video signals and displaying still and sub pictures in imaging systems such as televisions, video tape recorders, digital cameras, and various multimedia electronics. The delta sigma DAC is widely used in audio equipment. |
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Wednesday, 15 November 2006 |
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Digital filters are devices used for converting a sampled signal, received as an input, into another sampled signal having predetermined frequency response characteristics. The digital filter is capable of altering the magnitude, frequency, or phase response of a digital signal in accordance with the digital filter characteristics. Digital filters manipulate discrete samples of an input signal to produce a filtered output signal. Two basic types of digital filters are infinite impulse response filter (IIR filter) and finite impulse response filter (FIR filter). A FIR filter is used in real time digital signal processing applications for recovery of the transmitted information from the signal. Digital filters are primarily used in digital oscilloscopes, spectrum analyzers, and audio and video signal processors. |
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Sunday, 05 November 2006 |
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A load cell is used in a measuring device to convert sensed mechanical forces into a differential electrical signal. Load cells commonly function by utilizing an internal strain gage that measures deflection or sheer. A typical load cell includes one or more force sensing elements, such as strain gages, which are configured as an electrical bridge circuit. A load cell includes a counterforce and at least one force transducer such as a strain gage. A strain gage load cell is basically a metal structure subject to a load to be measured, with strain gages sensing strain in the loaded structure. Load cells may be used in combination with analog to digital circuitry for accurately measuring desired physical properties or conditions such as weight, gravity, vibration, acceleration, and fluid pressure. |
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Friday, 20 October 2006 |
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An oscilloscope is used to acquire, analyze and display electronic signal waveforms. Oscilloscopes are an essential for research, development, and manufacturing of electronic devices. Digital oscilloscopes operate by sampling a time varying analog signal periodically and storing the sample values in correlation with time in a waveform memory. A digital storage oscilloscope samples and digitizes the analog signal at a predetermined sample rate to produce a stream of digital data samples that represent the analog signal. Digital oscilloscope instruments have the flexibility of providing a wide range of storage, display and processing options. Digital oscilloscopes acquire information about the behavior of a circuit node by periodically sampling the voltage present at the node. |
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Tuesday, 17 October 2006 |
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A spectrum analyzer is a device or system that measures the power spectral density of a signal or one of several closely related signal parameters. A spectrum analyzer processes an input signal to separate and measure the individual spectral components of the signal, and to order them according to their frequency. Spectrum analyzers are employed in most of the modern signal processing systems for measuring the distribution of signal energy in frequency. Spectrum analyzers generally fall into two categories: sweep type spectrum analyzers and fast Fourier transform (FFT) based spectrum analyzers. A fast Fourier transform analyzer analyzes the response characteristic of an electrical device when supplied with a test signal. Optical spectrum analyzers are used for analyzing the output light beams. |
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Saturday, 07 October 2006 |
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An analog to digital converter (ADC) converts an analog input signal into a digital output represented by a coded array of binary bits. An analog-to-digital converter provides a digital bit stream output of either single or multiple digital bits that are representative of an analog input signal. Analog to digital converters allow the use of sophisticated digital signal processing systems to process analog signals. An analog to digital converter may be implemented utilizing sigma-delta technology, mash converter technology, successive approximation technology, flash converter technology. Flash ADC is performed by a highly parallel comparison of an input analog signal to each of a set of reference voltages. Pipelined A/D converters have high accuracy, high throughput rates, and low power consumption. |
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Tuesday, 19 September 2006 |
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Signal conditioners are used to optimally condition an output signal in a data acquisition system (DAQ). A data acquisition system includes transducers, transmitters, and amplifiers for provision of the signal representation by their measurement and/or monitoring. Most sensors and transducers generate signals that must be conditioned before a DAQ device can reliably and accurately acquire the signal. Data acquisition systems may be coupled to sensing and other input devices by signal lines, some providing analog signals, and digital signals. Adaptive signal conditioning systems are used for adaptively conditioning the input signal to a signal conversion system. Signal conditioning is critically important for wireless systems because electronic inputs can have different characteristics and ranges. |
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Tuesday, 12 September 2006 |
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Signal converters are electronic devices for converting one type of signal into another type of signal. A digital to analog converter (DAC) is typically composed of several DAC elements, which receive digital input data and generate element signals according to the digital input data. Digital-to-analog converters are employed in various demanding applications including direct digital synthesizers, arbitrary waveform generators, and transmitters. Analog/digital converters are electronic circuits that convert an analog input signal into a digital output signal. General types of A/D converters include comparator (flash) converters, successive approximation converters, and counting converters. Digital displays often contain an analog to digital converter (ADC) to sample each display signal frame. |
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Friday, 01 September 2006 |
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A data logger is used for logging or accumulating data received from a data source. Data logging is now widely used in computer simulation to provide a record of the activity of the simulated system for subsequent processing and analysis. A data logger may generally be described as a recording device for creating a time-sequence history of events. A data logger is made up of a digital processor operationally connected to a non-volatile memory bank for storing measurements obtained from electronic sensors in communication with the data logger. Typically, data loggers include probes or sensors which measure product environmental parameters and are connected to the data logger. Data loggers are employed in many industries to ascertain environmental parameters. |
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Thursday, 17 August 2006 |
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Data acquisition is the process of extracting, transforming, and transporting data from the source systems and external data sources to the host processing system to be displayed, analyzed, and stored. Data acquisition systems (DAQ) are used to perform a variety of functions, including laboratory research, process monitoring and control, data logging, analytical chemistry, tests and analysis of physical phenomena, and control of mechanical or electrical machinery. In data acquisition systems, information about a plurality of parameters is often obtained by simultaneously deploying numerous sensors. Data acquisition systems include sensors, transducers, and amplifiers. Data acquisition systems and methods may be used in a variety of applications. |
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Data Acquisition
