Thesis
Implementación de códigos correctores de errores para un módem para la comunicación sobre la red eléctrica
Autor
Ing. Martínez Cruz, Alfonso
Institución
Resumen
The development of turbo codes over the past two decades, has resulted in signi cant
performance improvement of PLC communication systems, considerable reduction of
the device size, development of more complex chips with channel coding support
and implementation of more robust modulation techniques. Today, some of the major
research problems are related to the implementation of e cient architectures for decoding
algorithms, development of techniques for e cient power consumption management, and
latency reduction in the hardware used.
The application of turbo codes in communication systems has been characterized for
use in di cult conditions for a conventional code. Some of these conditions include the
presence of high noise levels in the channel, which require devices to minimize systems
power consumption in which the transmission of information has a high cost. In this thesis
we present the implementation of the Max-Log-MAP algorithm in TMS320C6416T DSP.
We report the results obtained with Gaussian and impulsive noise contaminating the data
sent to the receiving device (DSP) as well as the behavior of the decoder for di erent SNR
(signal/noise relation). Speci cally the proposal includes the design implementation of the
encoder, interleaver, \puncturing" mechanism and decoding data. The implementation
presented in this thesis shows the bene ts of a high-performance code in a real application.
Based on tests performed on a channel with Gaussian and impulsive noise was observed
that increasing the length of the interleaver, the performance increase BER curves. It was
further observed that with a turbo encoder type RSC (5,7) the results are very close to
the RSC con guration (17,15), also RSC (31,27) encoder generated the best results. On
this basis it is possible to reduce hardware resources required to implement a turbo code
for the application in the PLC channel