Page 93 - ITUJournal Future and evolving technologies Volume 2 (2021), Issue 1

ITU Journal on Future and Evolving Technologies, Volume 2 (2021), Issue 1

PERFORMANCE OF A PARALLEL HAMMING CODING IN SHORT‑FRAME OFDM SENSOR’S
NETWORK

1
Raouia Masmoudi Ghodhbane and Jorge Fernandez‑Mayoralas 1,2
1 Safran Tech, Safran Sensing Systems ( ) , Rue des Jeunes Bois, Chateaufort , 78114 Magny‑les‑Hameaux, France,
3
̂
2 CentraleSupelec, Integrated Circuit and Electronic Systems, rue Joliot‑Curie, F‑91192 Gif‑sur‑Yvette Cedex, France.
NOTE: Corresponding author: Raouia Masmoudi Ghodhbane, raouia.masmoudi@gmail.com

Abstract – In this paper, we focus on the most relevant Error Correcting Codes (ECCs): the Hamming code and the Reed‑
Solomon code in order to meet the trade‑off between the low implementation complexity and the high error correction capac‑
ity in a short‑frame OFDM communication system. Moreover, we discuss and validate via simulations this trade‑off between
complexity (Hamming is the easiest to code) and error correction capability (Reed‑Solomon being the most effective). There‑
fore, we have to either improve the correction capacity of the Hamming code, or decrease the complexity cost for the Reed‑
Solomon code. Based on this analysis, we propose a new design of parallel Hamming coding. On the one hand, we validate
this new model of parallel Hamming coding with numerical results using MATLAB‑Simulink tools and BERTool Application
which makes easier the Bit Error Rate (BER) performance simulations. On the other hand, we implement the design of this
new model on an FPGA mock‑up and we show that this solution of a parallel Hamming encoder/decoder uses a few resources
(LUTs) and has a higher capability of correcting when compared to the simple Hamming code.

Keywords – error correcting codes, FPGA, Hamming code, parallel Hamming coding, OFDM communication systems,

Reed‑Solomon code, short‑frame, sensor’s network, VHDL simulation
1. INTRODUCTION for aeronauticsensor’s network[9, 10]. According to[10],
a PLC channel has major limitations especially in terms of
Nowadays, Orthogonal Frequency Division Multiplexing bandwidth, impedance mismatches and noise.
(OFDM) systems are increasingly used in several applica‑
tions such as: digital radio, television broadcasting sys‑ Since power consumption has been a critical factor in the
tems, mobile communication systems and Power‑Line design of sensor’s network, we consider sensor’s network
Communications (PLC). OFDM is a convenient modula‑ with short periods of activity, in which some sensors’ de‑
tion scheme which combines the advantages of high data vices go into standby mode. This consideration and the
rates and easy implementation. need for low latency access [11] to sensor data under‑
However, the main challenge associated with OFDM com‑ scores the need for a short‑frame OFDM and fast commu‑
munication systems today remains related to Error Cor‑ nication protocol.
recting Codes (ECCs) implementation [2]. Encoding and In this paper, we focus on a low‑powered short‑frame
decoding are very important blocks in OFDM systems in OFDM communication system where the sensors’ devices
which redundant information is added to the signal to send only one OFDM symbol per frame on the PLC chan‑
allow the receiver to detect and correct errors that may nel. We simulate and model the design of this low‑
have occurred in transmission. There are many tech‑ powered short‑frame OFDM communication system in
niques for error detection and correction such as: the terms of error correction. As mentioned previously, the
Hamming code [3], Turbo code [4], Bose, Chaudhuri, and complexityofthechosenECCisoneofthestudiedcriteria:
Hocquenghem (BCH) code [5], Reed‑Solomon code [6], the ECC has to be effective and fairly easy to implement at
Convolutional code/ Viterbi [7], and LDPC [8]. the same time.
One way to compare the ef iciency of several ECCs is to Usually, to have better performance in terms of error cor‑
compare their performance in terms of their complexity rection and/or error detection, we have to add several er‑
of implementation and their error detection or/and cor‑ ror correcting codes (ECCs) in serial either at the encoder
rection capability. Hamming and Reed‑Solomon codes or on the decoder level. Our case of applications requires
have proved to be a good compromise between ef iciency a very simple ECC in order to implement it on a High Tem‑
and complexity. Hamming is very easy to implement and perature (HT) ASIC whose number of cabled lip‑ lops and
does not consume many resources, and it is a robust ECC, multipliers are limited by the HT technology.
but the Bit Error Rate (BER) performance is not the most Therefore, the novelty of this paper lies in the perfor‑
effective. The Reed‑Solomon is more optimal to elimi‑ mance analysis of a new design based on the parallel
nate errors (especially for burst errors), but it is also more Hamming coding which meets the trade‑off between the
complex to implement. low implementation complexity and the high error cor‑
Our domain of application is PLC based on OFDM systems rection capacity. In the literature, the closest work to ours

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