Design and Performance of a Frequency Hopping Communications System Using Delta Modulation.

摘要

A way to increase jamming immunity and to decrease the intercept probability of a communication system is to use spread spectrum (SS) techniques. In this report a frequency hopping SS system (transmitter and receiver) is presented. This system is designed, built, and tested to send and receive digitized voice by utilizing a single chip delta modulator/demodulator. The report describes the circuitry employed, lists the important parameters of the system and includes photographs of various waveforms. The recovered audio is of good quality using digital data rates as low as 25 kilobits per second. A hopping rate of 100 hops per second is used in the design. (Author)