TRANSFER SYSTEM ON THE BASIS OF CHANNEL CODE 

Savel'ev Boris Aleksandrovich, Doctor of engineering sciences, professor, sub-department of data-computing systems, Penza State University (40 Krasnaya street, Penza, Russia), sba@pnzgu.ru
Kruchinina Mariya Vladimirovna, Postgraduate student, Penza State University (40 Krasnaya street, Penza, Russia), sba@pnzgu.ru 

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Background. Channel (linear) coding is widely used in local computing networks and in data recording on magnet and optic data storages. It is associated with simple construction of coders and decoders that transform signals by level and form, as well as provide the possibility of self-synchronization of a receiving device. It leads to the increase of the transfer rate or the rate of signal recording in the form of equal-length channel codes of Manchester type, NEW, where each binary bit is transformed into two half-bits of different polarity +1 and -1. It is similar to noise resistant coding with binary redundancy as (n, k) = (2k, k), where n – code length, k – length of the information segment of the code. It is suggested to use the NEW code redundancy also detection of received signal distortions. The article aims at modeling the work of the channel code to investigate error-detecting properties of the NEW channel code.
Materials and methods. On the basis of the analysis of the structure and form of channel codes it is possible to detect errors and destortions. Algebraic methods of error detection probability assessment using the NEW channel code are quite difficult, and therefore the article suggests to model transfer systems on the basis of the Simulink package, that allows applying statistical methods of assessment of channel code’s correcting properties. Error-detecting properties of equal-length channel codes in combination with noise resistant codes significantly increase correcting properties of systems of data transfer fidelity improvement.
Results. The authors developed a model of the system of data transfer by the NEW channel code consisting of a coder and decoder model on the basis of Simulink package standard blocks. Decoder performance is controlled by the Scope and Display blocks. At the reception the signals are registered by the method of strobing by the synchronization unit. Display signal blocks provide enumeration of received data element errors.
Conclusions. The developed and tested model of the transfer system on the basis of the channel code allows assessing of error-detecting properties of the NEW code that may be efficiently used in cascading systems of noise resistant data coding. Experimental testing results may be compared with data obtained through reduced mathematical expressions. 

channel code, model, transfer system, coding, decoding, detection of errors, noiseproof code. 

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