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Energy Aware Error Control in Cooperative Communication in Wireless Sensor Networks

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Abstract

Due to small size of sensor nodes deployed in Wireless Sensor Networks (WSNs), energy utilization is a key issue. Poor channel conditions lead to retransmissions and hence, result in energy wastage. Error control strategies are usually utilized to accommodate channel impairments like noise and fading in order to optimize energy consumption for network lifetime enhancement. Meanwhile, cooperative communication also emerges to be an appropriate candidate to combat the effects of channel fading. Energy efficiency of cooperative scheme when applied with Automatic Repeat Request (ARQ), Hybrid-ARQ (HARQ) and Forward Error Correction (FEC) is investigated in this work. Moreover, the expressions for energy efficiency of Direct Transmission, Single Relay Cooperation and Multi Relay Cooperation are also derived. In all, our work is focused towards energy optimal communication in WSNs. Our results show that error control strategies with cooperative schemes can significantly enhance system performance in form of energy optimization.

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... This will increase the latency and lengthen the delaythen eventually will use more energy. FEC might not flood the network with retransmission packets or cause irrelevant congestion, however, the usage of FEC creates more complexity in terms of the decoding process and in some cases can also consume more energy [7].Hybrid Automatic Repeat Request (HARQ) were being studied and implemented in order to minimize the overheads of ARQ and FEC. HARQ is the conventional combination of ARQ and FEC. ...
... The main purpose of FEC is to encode messages by using an error correction code (ECC). FEC coding techniques are classified as block and convolutional codes [17,18]. The Hamming coding system is a kind of binary block code method used in telecommunications [19]. ...
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... Therefore, it is important to apply the channel codes to the system to detect and correct the errors and to gain the system's performance [7]. Moreover, the channel coding could also provide the energy efficiency [8] and increase the network's lifetime in the cooperative systems [9]. ...
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