Multiplex telemetering system

Abstract

A multiplex telemetering system for transmitting a group of data signals each representing a distinct analog value, over a common channel to a receiving terminal where the data signals are fed into respective sub-channels. The transmitter includes a commutator formed by a series of individually actuatable switches which sequentially supply the data signals to the common channel. At the receiving terminal, the data signals are distributed by a corresponding commutator to the several sub-channels. In order to synchronize the operation of the commutators, an address generator at the receiving terminal cyclically produces a series of multi-bit binary values the number of values in the series equalling the number of switches in each commutator. The series of binary values generated are decoded to produce control voltages for sequentially actuating the receiver commutator switches, the binary values also being translated into an audio signal mixture composed of different frequencies representing the bits of the binary code. The signal mixture produced at the receiving terminal is conveyed over the common channel to the transmitter, the mixture being superimposed on the data signals. The signal mixture is intercepted at the transmitter and the frequencies thereof segregated from each other and restored to a series of binary values which are decoded to produce control voltages for synchronously actuating the transmitter commutator switches.