Design and Realization of FH-CDMA Scheme for Multiple-Access Communication Systems

In this paper we proposed the Frequency Hopping Code Division Multiple Access (FH/CDMA) Scheme. In order to improve the spreading process of the spread spectrum modulation system, the conventional pseudo-random code has been replaced by chaotic signal owing to its dynamical behaviour. The spreading code generator has been implemented using discrete integrated circuits and components in which output is controlled by a conventional PN code. The proposed circuit has been tested using real time voice signal and has been transmitted as frequency hopping signal with different hopping patterns. A FH/CDMA Transmitter and Receiver based on proposed chaotic signal generator has been experimentally verified. The results of experimental investigation have been presented in the paper. The waveforms obtained at various check nodes have also been presented.