Data Acquisition Digital storage

The number of data points to be chosen in the Fj and F2 domains is dictated not only by the desired resolution but by other, external considerations, such as the available storage space in the computer, and the time that can be allocated for data acquisition, transformation, and other instrument operations. Clearly, to avoid any unnecessary waste of time, we should choose the minimum resolution that would yield the desired information. Thus, if the peaks are separated by at least 1 Hz, then the desired digital resolution should be R/2 = V2 Hz to allow for signal separation in the F domain. The resolution considerations in the F and F domains may be different, depending on what information is required from each domain... 

For some mass spectrometers, such as TOF mass spectrometers, for reasons of data transfer speed and data storage capacity, the data acquisition system needs to accumulate data for a period of time in the summing memory, and forward the accumulated data to the data system. Each spectrum is added to the sum of the previous spectra so that a continuous summation process takes place. This type of data acquisition system is called digital signal averaging (DSA) or integrating transient recorder (ITR). Figure 3.8 illustrates the principle of mass spectrum acquisition with this type of system. 

G. I. Ouchi, Chromatographic data acquisition Analog to digital conversion and raw data storage, LC-GC 9(7) (1991), 474-477. 

The two most popular data-acquisition systems are the strip-chart recorder and the digital data-storage system. The latter is used when a great deal of data processing is anticipated. 

There has been a tremendous growth in the study of human movement in the past 2 decades because of the low cost of digital data acquisition systems that make possible the storage and analysis of massive amounts of data that are required to accurately characterize complex motion. This growing interest in the study of human movement is coming from five predominate groups ... 

Data acquisition—converts the analog input signal into a digital equivalent for storage. Data control signals are routed to a microprocessor through an I/O port. 

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