ICTACT Journal on Communication Technology

Arnab Nandi ¹, Sumit Kundu ¹

Affiliations
1 Department of Electronics & Communication, National Institute of Technology, Durgapur, Durgapur-713209, IN

Abstract

Design of an energy efficient wireless sensor network (WSN) has emerged as an important research area. Minimizing energy consumption is the primary objective for WSN. WSN is usually characterized by tiny size, low cost and low transmission power. So optimization of transmission power is of great importance. Optimal transmit power not only achieves better network lifetime but also reduces inter-node interference significantly. In this paper we carry out simulation studies to investigate the effects of Rayleigh fading on the performance of WSN and optimal transmit power in presence of Rayleigh fading is derived. The effects of bit rate and Rayleigh fading on optimal transmit power are investigated under several network conditions. In this paper the network performance is estimated in terms of a quality of service (QoS) constraint given by the maximum tolerable bit error rate (BER). The derived optimal transmit power maintains a minimum BER constraint. The impact of fading on critical bit rate i.e., the bit rate below which a desired BER can not be achieved with any amount of transmit power is also studied.

Keywords

Sensor Networks, Power Control, Network Connectivity, Rayleigh Fading.

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Mousam Chatterjee ¹, Banani Basu ², Arnab Nandi ², Chanchal Kumar De ¹

Affiliations
1 Department of Electronics and Communication Engineering, Maulana Abul Kalam Azad University of Technology, IN
2 Department of Electronics and Communication Engineering, National Institute of Technology, Silchar, IN

Abstract

Performance of a single relay-based cooperative communication system in a wireless network is analyzed in this article. A single relay equipped with a single antenna employs a hybrid relay scheme. Based on the channel condition, either amplify or forward (AF) or adaptive decode and forward (ADF) scheme is employed in hybrid mode, which permits switching between the above mentioned dualistic schemes. The performance of the hybrid relay scheme has been examined in terms of symbol error rate (SER), outage probability and optimal power distribution for uncoded cooperative communication. A closed-form depiction for SER and outage probability for M-PSK signal has been derived, where the relay and the destination are considered to perform MRC combining of the message.

Keywords

Amplify and forward (AD), Adaptive Decode and Forward (ADF), SNR-based Adaptive Decode and Amplify Forward (SNR-ADAF), Symbol Error Rate (SER), Outage Probability.

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