A spread spectrum communication technique

Abstract

A practical solution to the problem of realizing a signal processing method for a covert voice communications system was the objective of the thesis. Spread spectrum technology in the form of Golay complimentary sequences implemented with acoustic surface wave devices was utilized to achieve this processing. The resultant device was an audio transceiver MODEM in which a specially coded form of pulse code modulation (PCM) was applied to a voice signal to enable application of the spread spectrum concept. The techniques exploited spread the 3 KHz voice modulation over a one MHZ bandwidth. A method of PCM synchronization with a minimum of data loss and a minimum amount of actual hardware. Highly involved theoretical analysis was de-emphasized in the thesis in order that engineering requirements could be satisfied in the working device that resulted.