Transmitter for forming non-linear pulse code modulated samples of analog signals by timing the integral of signal samples

Claim 1

A transmitter for forming non-linear pulse code modulated signals from analog signals, in which the amplitude range of the analog signals is divided into segments, comprising means for forming signal samples of said analog signals, a first analog-to-digital converter for converting the amplitude values of the samples of the analog signals into segment code words specifying the segments containing the amplitude values; an amplitude controller coupled to the first analog-to-digital converter and to the samples of the analog signals and having a sawtooth-shaped control characteristic, the amplitude controller comprising an integrator to which each analog signal sample is applied, a threshold unit connected to the integrator, and a control member for terminating the integration at a number of fixed timing control instants after the starting timing instant of each signal sample, said control member being in operation when the integrator voltage exceeds the threshold voltage of the threshold unit and at the last control timing instant of the said number of control timing instants; and a second analog-to-digital converter to which the amplitude-controlled signal samples from the integrator are applied for converting the controlled analog amplitude values from the integrator into amplitude code words specifying the controlled amplitude values.