Abstract: In a delta-modulation encoding arrangement having step-size control drift voltages and miss-match between the charge and discharge pulses for the first integrating network in the feedback circuit produce an additional DC voltage on this integrating network. This additional DC voltage is compensated by an additional feedback circuit comprising a second integrating network. However, if the signal to be encoded rapidly decreases from a large to a small amplitude and when after this rapid decrease the information signal only has a small amplitude an additional distortion is introduced for these small signals. To obviate this a modulation arrangement is included in the extra feedback circuit, which modulation arrangement is controlled by a control signal which derives a control signal from the delta modulation output pulses.

Abstract: An interpolating non-recursive digital filter for generating output signal samples which occur at a given output sampling frequency and which are related in a predetermined way to a sequence of input signal samples has an output sampling frequency which is an integer multiple of the frequency of the input signal samples. In order to make more efficient use of the storage capacity of a storage device in the filter, multiplying coefficients representative of the difference between two samples of the impulse response which belong to different sets but to the same sampling period are used.

Abstract: A receiver in an adaptive pulse code modulation transmission system is provided with a pulse pattern analyzer which is responsive to at least two sequential information pulses, and a correction circuit controlled by the pulse pattern analyzer for correcting the last transmitted pulse group.

Abstract: The invention relates to transmission systems with dynamic compansion for the coded transmission of speech signals. By the use of a limiting device in the dynamic control circuit of the receiver the intelligibility is improved. The limiting device is such that the dynamic range of a transmitted signal is limited so that no relevant information is lost in the period the human ear needs to adapt itself to rapid sound variations.

Abstract: System comprising an integrating digital signal processing device to which input signal samples x(nT) are supplied with a period T and which supplies output signal samples z(mrT) with a period rT. To this end in this integrating signal processing device consecutive groups having a period rT and consisting of r successive consecutive signal samples are processed beforehand in a non-recursive digital filter for generating auxiliary signal samples y(mrT) which occur with a period rT, the last mentioned samples being integrated in an integrating network for generating the output signal samples z(mrT).

Abstract: A digital circuit arrangement for directly converting compressed DM or DPCM signals into PCM signals, comprising a digital filter and a step size control circuit in which a DM bit or a DPCM code word and the associated step size code word are simultaneously applied to the digital filter.

Abstract: An interpolating non-recursive digital filter in which the circulating storage device which has a periodically changing storage time, is controlled by a clock-pulse generator, and has an output circuit whereby within one input sampling period the input code words stored in the storage device are supplied a predetermined number of times to the multiplying device.

Abstract: A digital filter is described in which the filter coefficients which differ from zero are coded in unequal numbers of multipliers which are equal to 2.sup.n and in which immediately after each multiplication of a given signal sample by the multipliers of the relevant filter coefficent a new signal sample is processed in the multiplying devices by the relevant multipliers. Thus the signal samples are applied to the multiplying device at instants which are mutually set independently of one another.