performance analysis of cooperative ofdm networks under the constraint of timing and frequency offsets
Ezhilazhagan.C, Arul.U,Kavya Kumar,Saravana Kumar.A,Ramakrishnan.M
Published in International Journal of Advanced Research in Computer Networking,Wireless and Mobile Communications
ISSN: 2320-7248 Impact Factor:1.8 Volume:1 Issue:1 Year: 08 November,2013 Pages:1-6
Abstract
In this paper, we show the performance improvement in a cooperative Orthogonal Frequency Division Multiplexing (CO-OFDM) network employing Amplify-andForward & Decode-and-Forward relaying strategies under the influence of both Carrier Frequency Offset (CFO) and Timing Offsets (TO). Multiple distributed nodes in cooperative networks are generally subject to Carrier Frequency Offset and Timing Offsets. Cooperative transmission, in which a source and relay cooperate to send a message to a destination, can provide diversity against fading in wireless networks. The key idea in user-cooperation is that of resource-sharing among multiple nodes in a network. The Symbol Error Rate (SER) performance of Amplify and Forward technique (AF), Decode and Forward technique (DF) and direct communication using OFDM subcarriers in a cooperative network with a single relay between Base Station and Mobile Station is presented. The cooperative OFDM networks employing AF and DF relaying strategies show an error performance with a better correlation to theoretically calculated values after the joint compensation using ML estimation for timing and carrier frequency offsetsIn this paper, we show the performance improvement in a cooperative Orthogonal Frequency Division Multiplexing (CO-OFDM) network employing Amplify-andForward & Decode-and-Forward relaying strategies under the influence of both Carrier Frequency Offset (CFO) and Timing Offsets (TO). Multiple distributed nodes in cooperative networks are generally subject to Carrier Frequency Offset and Timing Offsets. Cooperative transmission, in which a source and relay cooperate to send a message to a destination, can provide diversity against fading in wireless networks. The key idea in user-cooperation is that of resource-sharing among multiple nodes in a network. The Symbol Error Rate (SER) performance of Amplify and Forward technique (AF), Decode and Forward technique (DF) and direct communication using OFDM subcarriers in a cooperative network with a single relay between Base Station and Mobile Station is presented. The cooperative OFDM networks employing AF and DF relaying strategies show an error performance with a better correlation to theoretically calculated values after the joint compensation using ML estimation for timing and carrier frequency offsets
Kewords
AF relay, DF relay, Maximum ratio combiner, ML estimation, OFDM systems, SER performance.
Reference
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