'Improvements introduced into a method for determining the amplitude I the average DC level appearing in a given period of time in an analog signal'.

摘要

The system (Fig. 1) includes a conventional N bit analog-to-digital converter (12) and also includes a variable gain amplifier (68, 76) and DC offset control circuit (80) to adjust the amplitude and DC level of a received analog input signal prior to its application to the converter. In order to assure use of the full N bit capacity of the converter, without regard to the amplitude and DC level of the received analog input signal, the number of lowest value (all 0's) and the number of highest value (all 1's) words produced by the converter are compared to respective threshold values and, on the basis of those comparisons, signals are generated for controlling the variable gain amplifier and the DC level control circuit. IMAGE