'Defence Scientific Information and Documentation Centre'
Doi
Abstract
In the present-day scenario, digital communication has become predominant choice overanalog communication worldwide. Digital modulation schemes form the main block of the digitalcommunication. Among these, frequency shift keying (FSK-2) is a widely used technique employedfor Baudot-coded english text transmission. A Baudot-coded-FSK-2 modulated signal wassimulated corresponding to an english text file. A technique has been developed for its analysisand decoding in the MATLAB environment. This technique does the signal analysis, its parameterextraction, and then digital demodulation, to retrieve its corresponding composite bit-stream. Anefficient method for edge detection using the number of zero-crossings has been devised andimplemented successfully. From the composite bit-stream, overhead bits were removed anddecoding was performed to get back the text output
