Abstract
Scrambler is a device that performs one-to-one mapping between input data bits and channel codes. It is used in synchronous data communication systems to retrieve timing information from the received data i.e. to aid synchronization between two modems. Present paper deals with the computer-aided simulation and spectral analysis of the scrambler to be used in 56Kbps voice-band modem. Matlab has been used for simulation and pre-spectral analysis including power spectral density, cross-correlation and auto-correlation. Implementation of scrambler has been done on Texas Instrument’s TMS320C50 digital signal processor (DSP) and post- spectral analysis has been performed using Signalogic DSP software. Simulated and practical results have been found identical, which ensures the successful implementation of scrambler.
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Acknowledgements
One of the authors Davinder Pal Sharma is thankful to Guru Nanak Dev University, India, for providing DSP Research facilities at Department of Electronics Technology for present research work.
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Sharma, D.P., Singh, J. Simulation and Spectral Analysis of the Scrambler for 56Kbps Modem. J Sign Process Syst 67, 269–277 (2012). https://doi.org/10.1007/s11265-010-0551-0
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DOI: https://doi.org/10.1007/s11265-010-0551-0