Importance

Loading Importance Indicators...

Abstract

A high level, staircase type of quasi-analog reconstruction of an analog input signal, such as an audio signal, initially involves a conventional derivation of a PCM signal from the analog input signal. The binary bits of each PCM codeword are considered as being C in number, of which an A number are major bits and a B number are minor bits. The A number of bits are converted to (2.sup.A -1) discrete decimal data bits, each of which controls the switching to and from a series voltage summation line of a discrete voltage V.sub.c, where ##EQU1## and V.sub.max is substantially the peak kilovolt amplitude to be provided in the reconstructed signal. Individual ones of the B bits directly control the individual switching to and from the summation line of discrete voltages of unequal magnitudes declining in one-half voltage increments from Vc/2 to Vc/2.sup.B. Alternatively, individual bits of N more significant bits of the B bits directly control the individual switching to and from the summation line of discrete voltages of unequal magnitudes declining in one-half voltage increments from Vc/2 to Vc/2.sup.N, while the remaining (B-N) bits are converted, in combination, to an analog control voltage which drives a step voltage follower whose output is permanently connected in series with the summation line to add thereto a step voltage in the range of from Vc/2.sup.N+1 to Vc/2.sup.B where the step voltages decline in one-half voltage increments.

Loading the Abstract Image...

First Claim