Author_Institution :
Clarke-Hess Commun. Res. Corp., Long Island City, NY, USA
Abstract :
This paper provides a unified technique to deal with a number of open-ended, digital adjustment and/or correction techniques that have grown up as “special cases.” These include corrections for system imperfections in channel matching, in frequency response, and/or in transient response. In the situations under consideration there is always a controlling variable, such as signal amplitude, and a controlled or correctable variable, such as the transient response. All of the systems to be corrected require a combination of: stability, the ability to sort the controlling variable, a digital storage mechanism, a control or correction mechanism, and a standard to provide the means to adjust the final results to within the desired tolerance. The methods are illustrated with results from an actual, digitally sampling, two-channel, seven-amplitude range, 10 MHz, 100 A, pulse current generating and measuring system. These results include the digital correction of the transient response of the system and introduce a 100 A “flatness standard.” By using these concepts one may usually achieve at least a ten times reduction in the uncertainty in the transfer function of the system that is adjusted or corrected
Keywords :
analogue-digital conversion; electric current measurement; error correction; frequency response; gain control; measurement uncertainty; piecewise linear techniques; pulse measurement; signal sampling; transfer functions; transient response; 10 MHz; 100 A; ADC; bin selection; channel matching; controlling variable; correctable variable; digital adjustment; digital correction; digital sampling; digital storage mechanism; flatness standard; frequency response; gain control; generalized framework; open-ended techniques; piecewise linear model; pulse current generating and measuring system; signal amplitude; software corrections; system imperfections; tolerance; transfer function uncertainty; transient response; two-channel seven-amplitude range; uncertainty reduction; Control systems; Current measurement; Digital control; Frequency response; Pulse generation; Pulse measurements; Sampling methods; Stability; Transfer functions; Transient response;