Performance analysis of AF cooperative networks with time-varying links: Error rate and capacity

In this paper, we consider an M-relay amplify-and-forward (AF) cooperative system with maximal ratio combining (MRC) at the destination and investigate the effects of both the mobile cooperating-nodes speeds and the receivers' channel state information (CSI) estimation rates on the system performance. By CSI estimation rates we mean how much the receivers' tracking loops are fast to estimate the channel gains over the individual time slots. The fading links are considered to be frequency-flat time-varying Rayleigh fading and modeled by a first-order autoregressive process (AR1). General closed-form approximate expressions are derived for the bit error rate and the system Shannon capacity, which are further verified through Monte Carlo simulations. These expressions are valid for time-varying as well as quasi-static fading links for both low and high CSI estimation rates. Furthermore, we analytically show that, due to high speeds of the cooperating-nodes and/or constrained CSI estimation rates, both of the error rate and the capacity suffer from asymptotic limits. These limits could be completely eliminated by a well-designed fast tracking loops at the receivers even though the speeds of the mobile nodes are relatively high.

[1]  Salama Ikki,et al.  Error Probability of DF Relaying with Pilot-Assisted Channel Estimation over Time-Varying Fading Channels , 2012, IEEE Transactions on Vehicular Technology.

[2]  W. C. Jakes,et al.  Microwave Mobile Communications , 1974 .

[3]  George K. Karagiannidis,et al.  Amplify-and-Forward Relay Selection with Outdated Channel Estimates , 2012, IEEE Transactions on Communications.

[4]  Ronald A. Iltis,et al.  Joint estimation of PN code delay and multipath using the extended Kalman filter , 1990, IEEE Trans. Commun..

[5]  Gregory W. Wornell,et al.  Cooperative diversity in wireless networks: Efficient protocols and outage behavior , 2004, IEEE Transactions on Information Theory.

[6]  Elza Erkip,et al.  User cooperation diversity. Part II. Implementation aspects and performance analysis , 2003, IEEE Trans. Commun..

[7]  Syed Ali Jafar,et al.  Impact of mobility on cooperative communication , 2006, IEEE Wireless Communications and Networking Conference, 2006. WCNC 2006..

[8]  Mazen O. Hasna,et al.  End-to-end performance of transmission systems with relays over Rayleigh-fading channels , 2003, IEEE Trans. Wirel. Commun..

[9]  A. Goldsmith,et al.  Capacity of Rayleigh fading channels under different adaptive transmission and diversity-combining techniques , 1999, IEEE Transactions on Vehicular Technology.

[10]  Matthias Pätzold,et al.  Performance Analysis of Cooperative Communication Systems with Imperfect Channel Estimation , 2009, 2009 IEEE International Conference on Communications.

[11]  Ha H. Nguyen,et al.  On the capacity of Rayleigh fading cooperative systems under adaptive transmission , 2009 .

[12]  Georgios B. Giannakis,et al.  Estimation and equalization of fading channels with random coefficients , 1996, Signal Process..

[13]  MohammadAli Mohammadi,et al.  Impact of Unknown Time-varying Fading on the Information Rates of Amplify and Forward Cooperative Systems , 2013, IEEE Transactions on Wireless Communications.

[14]  Norman C. Beaulieu,et al.  Optimum Pilot Symbol Assisted Modulation , 2007, IEEE Transactions on Communications.

[15]  Ha H. Nguyen,et al.  Performance of Differential Amplify-and-Forward Relaying in Multinode Wireless Communications , 2013, IEEE Transactions on Vehicular Technology.

[16]  Xing Zhang,et al.  Performance Analysis of OSTBC Transmission in Amplify-and-Forward Cooperative Relay Networks , 2010, IEEE Transactions on Vehicular Technology.

[17]  Elza Erkip,et al.  User cooperation diversity. Part I. System description , 2003, IEEE Trans. Commun..

[18]  Hong Shen Wang,et al.  On verifying the first-order Markovian assumption for a Rayleigh fading channel model , 1994, Proceedings of 1994 3rd IEEE International Conference on Universal Personal Communications.

[19]  Mostafa Kaveh,et al.  Exact symbol error probability of a Cooperative network in a Rayleigh-fading environment , 2004, IEEE Transactions on Wireless Communications.

[20]  Xiangyun Zhou,et al.  Kalman filter-based channel estimation for amplify and forward relay communications , 2009, 2009 Conference Record of the Forty-Third Asilomar Conference on Signals, Systems and Computers.