Page 97 - ITUJournal Future and evolving technologies Volume 2 (2021), Issue 1
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ITU Journal on Future and Evolving Technologies, Volume 2 (2021), Issue 1




               manages to converge to no errors for         = 8dB,  10 0
             3
                                                   0
          which represents the noise level that we will  ind in the                           Hamming Simple CR 2
          real PLC channel.                                        -1                         Fit Hamming Simple CR 2
                                                                 10
                                                                                              Reed-Solomon CR
                                                                                                         2
                                                                                              Fit Reed-Solomon CR
          3.3 Discussion and comparison                          10 -2                                     2
          As we discussed before, the complexity and the capacity
          of error correction of the chosen ECC are the most impor‑  BER  10 -3
          tant criteria: the ECC has to be effective and fairly easy to
          implement at the same time.                            10 -4
          The capacity of error correction of each ECC is known and
          depends on its structure and their way of coding the in‑  10 -5
          formation. Table 3 summarizes the detection and correc‑
          tion capability of each ECC scheme. We denoted here by  10 -6
                                                                                         6
          SED/DED/MED: the Single/Double/Multiple Error Detec‑      0      2      4   E /N  (dB)  8   10     12
          tion, and by SEC/DEC/MEC: the Single/Double/Multiple                         b  0
          Error Correction.                                    Fig. 5 – Comparing the simple Hamming code to the Reed‑Solomon code

          Table 3 – The capability of error detection or/and error correction for  parallel Hamming coding in order to increase the error
          each ECC.
                                                               correction capability of our model.
           ECC            SED SEC    DED DEC MED MEC
                                                               4.   PARALLEL      HAMMING       CODING      RE‑

           Hamming        x    x                                    SULTS USING MATLAB‑SIMULINK AND
           code                                                     BERTOOL
           Extended
                          x    x     x                         In this Section, we have selected only a few of the most il‑
           Hamming
           Reed‑                                               lustrative and interesting scenarios to be presented here.
           Solomon        x    x     x    x    x     x         In order to plot the Bit Error Rate (BER) function of the
                                                                       which is given in equation (1), we have used the Mat‑
           Code                                                    0
           BCH Code       x    x     x    x    x     x         lab tools called ”BERTOOL”.

          While the Hamming code can be implemented creating   4.1 BER performance analyser for MATLAB‑
          just two fairly simple modules (encoder/decoder) based     Simulink models
          on XOR gates, the Reed‑Solomon code requires a higher
          number of blocks. In fact, the Reed Solomon encoder  Here, we use the Bit Error Rate (BER) analysis GUI (called
          needs: Adder in Galois Field, Multiplier in Galois Field,  BERTool) from Matlab application. The BERTool appli‑
          Multiplex and Registers [13]. The Reed‑Solomon decoder  cation is able to analyze the BER performance of differ‑
          needs algorithms to decode the code word such as: Syn‑  ent communications systems as a function of signal‑to‑
          drome calculator; Berlekamp‑Massey algorithm (or Eu‑  noise ratio         given in equation (1). It analyzes perfor‑
                                                                            0
          clid algorithm)which  inds the location of the errors by  mance either with Monte‑Carlo simulations of MATLAB
          creating an error locator polynomial; Chien Search Algo‑  functions and MATLAB‑Simulink models or with theoreti‑
          rithm which  inds the roots of the previous polynomial;  cal closed‑form expressions for selected types of commu‑
          Forney’s algorithm where the symbol’s error values are  nication systems[14].
          found and corrected. Thus, these blocks are complex and
          use multiplications (or RAM memory if we use tables).
          Here, we have simulated in Fig. 5 the Hamming code and
          the Reed‑Solomon code for the same coding rate      in
                                                       2
          order to compare their BER performance.
          The Hamming and Reed‑Solomon codes have proved to
          be a good compromise between ef iciency and complex‑
          ity. Hamming is very easy to implement and does not con‑
          sume many resources, and it is a robust ECC, but the Bit
          Error Rate (BER) performance (in Fig. 5) shows that it is
          not the most effective ECC. Reed‑Solomon is more opti‑
          mal to eliminate errors, but it is also more complex than
          the Hamming code.
          In the following Section, we will propose a new model of  Fig. 6 – Bertool Interface: steps to plot the BER vs EB/No simulations





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