
Accession Number : AD0724780
Title : Digital Signal Sinusoidal Modulation (DSSM),
Corporate Author : NATIONAL BIOMEDICAL RESEARCH FOUNDATION SILVER SPRING MD
Personal Author(s) : Cheng,George C. W.
Report Date : AUG 1962
Pagination or Media Count : 12
Abstract : In communication theory, the inverse relationship between the pulse duration and the frequency spectrum bandwidth of the pulse has been extensively studied. In order to obtain a satisfactory digital signal transmission, the system bandwidth has to be greater than K/T cps., where T is the duration in sec. of the narrowest pulse of the signal source and K is a constant depending on the pulse shape and usually greater than 1. This is a well accepted doctrine in the design and analysis of digital signal communication systems. However, the following introduced Digital Signal Sinusoidal Modulation (DSSM) does not obey this golden rule. Theoretically, the desired frequency bandwidth of the modulator and demodulator of the DSSM system is zero. Practically, the bandwidth of the modulator or demodulator is limited only by the practical engineering skill and is independent on the signals. The difference in principle between the conventional modulation techniques and the LDSSM is that the former is a nonlinear signal process, whereas the latter is a linear process. Therefore the superposition principle applies to the DSSM. (Author)
Descriptors : (*INFORMATION THEORY, PULSE COMMUNICATIONS), CIRCUITS, FREQUENCY MODULATION, INTEGRAL TRANSFORMS, NUMERICAL ANALYSIS, DIGITAL COMPUTERS
Subject Categories : Computer Hardware
Cybernetics
Distribution Statement : APPROVED FOR PUBLIC RELEASE