Abstract: The invention is an apparatus and method for multiplexing digital informan acquired from a multiplicity of data terminals distributed along a conductor of given length. A cyclic synchronization signal consisting of a stream of coding periods is transmitted upon the conductor. The duration of each coding period exceeds the two way travel time through the conductor. The leading edge of a coding period stimulates the transmission of one bit of a digital word stored in each terminal. The bits from the terminals arrive at a system receiver in a time sequence corresponding to the spatial distribution of the terminals. Bits are collected in storage registers according to their significance which is determined by the respective coding period during which they are received. A word from a particular terminal is derived by strobing the output of the storage registers at the time corresponding to the position of the terminal.

Abstract: Apparatus, useful in signal processing, and which can be used for modulo (2.sup.n -1) addition, subtraction, coding, and decoding, has a plurality of 2n input means: n means for receiving a signal I.sub.0, I.sub.1, . . . , I.sub.n-1, and another n means for receiving a signal J.sub.0, J.sub.1, . . ., J.sub.n-1. A pluraity n of means, connected to the n I signal input means, may switch each input means so that it is connected alternately into one of two connecting points, a first and a second connecting point. A plurality n of means is connected to the n first connecting points, for inverting the polarity of a signal received at its input, the output of the inverting means being connected to its associated second connecting point. A plurality n of three input adding means, has one input connected to the output of the inverting means, and another being connected to an associated means for receiving a J signal, the means adding the two inputs.