Digital speech transmission method using a single radio channel

Abstract

Abstract 1. Method for the digital transmission of speech by way of a single radio channel between two subscribers A and B each with a respective simplex radio set, in which always either the sending section or the receiving section is switched through, wherein the station just sending briefly interrupt its emission at regular time intervals and switches through the receiving path in order to ascertain wheter the counter-station intends to speak, characterized by the following features : - In both radio sets, the own speech amplitude is determined in parallel to the conversion of the speech into a bit current and digitalised on the one hand and conducted to a comparator on the other hand - In the sending radio set, the digitalised speech amplitude is periodically inserted into the bit current to be emitted and in the receiving radio set filtered out, converted and conducted to the comparator ; if the received speech amplitude at the comparator is lower than the own speech amplitude of the receiving radio set, then the speech direction is switched over. - In the receiving radio set, the transmitter is switched on briefly at the same periodicity, but displaced by a suitable time span, and the digitalised speech amplitude is emitted and received in the sending radio set by the receiver briefly switched on in synchronism, converted and conducted to the comparator ; if the received speech amplitude at the comparator is higher than the own speech amplitude of the sending radio set, then the speech direction is switched over.

Inventors

• 👤 Karl Dipl.-Ing. Fischer
• 👤 Wolfgang Dr.-Ing. Schaller

Bibliographic Details