Improved OFDMA uplink transmission <i>via</i> cooperative relaying in the presence of frequency offsets—Part I: Ergodic information rate analysis

Zhang, Zhongshan; Tellambura, Chintha; Schober, Robert

doi:10.1002/ett.1384

Cited by 22 publications

(8 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Relay selection is proven to be one of the most efficient methods to improving the spectral efficiency and maximizing the spatial diversity gain at the same time in multiple-relay systems [13][14][15][16][17][18]. By selecting the optimal relay from multiple candidates, only one relay is active in each time so as to improve the spectral efficiency considerably, with full spatial diversity gain being obtained.…”

Section: Introductionmentioning

confidence: 99%

Impact of partial relay selection on the capacity of communications systems with outdated CSI and adaptive transmission techniques

Zhong

Zhang

et al. 2013

J Wireless Com Network

Self Cite

View full text Add to dashboard Cite

The impact of outdated channel state information (CSI) on the capacity of amplify-and-forward (AF) partial relay selection systems is studied in this article. The closed-form expressions for the distribution of received signal-to-noise ratio (SNR) in a multi-relay cooperative communications system is first derived, with independent and identically distributed (i.i.d.) Rayleigh fading channels being assumed in each wireless link. After that, the theoretical closed-form expressions for both outage probability and channel capacity of partial relay selection are derived, with four classical adaptive transmission techniques, including the constant power with optimal rate adaption (ORA), the optimal power and rate adaption (OPRA), the channel inversion with fixed rate (CIFR) and truncated channel inversion with fixed rate (TIFR), being considered. Numerical analysis proves that the channel capacity of partial relay selection is impacted considerably by some critical parameters, including the number of relays, the channel correlation coefficient and the end-to-end SNR, etc. It's also exhibited in the numerical results that among the four adaptive transmission techniques, the diversity order of OPRA is larger than that of TIFR, and the OPRA outperforms TIFR with about 0.15 bits/s/Hz in terms of average channel capacity.

show abstract

Section: Introductionmentioning

confidence: 99%

Impact of partial relay selection on the capacity of communications systems with outdated CSI and adaptive transmission techniques

Zhong

Zhang

et al. 2013

J Wireless Com Network

Self Cite

View full text Add to dashboard Cite

show abstract

“…Relay selection is one of the most attractive methods to solve the complicated interference-mitigation issue met in the multi-relay systems. Selecting the best relay to forward data is an ideal method to maintain a full diversity gain and improve the spectral efficiency at the same time [12], [13]. Furthermore, only two time slots or two orthogonal channels (regardless of the number of relays) are required [14].…”

Section: Introductionmentioning

confidence: 99%

Best relay selection in decode and forward cooperative cognitive radio relay networks over Rayleigh fading channels

Li¹,

Zhang²,

Zhang³

et al. 2013

IET International Conference on Information and Communications Technologies (IETICT 2013)

View full text Add to dashboard Cite

The performance of the best relay selection on the decodeand-forward (DF) mode cognitive radio relay networks is studied. Some important factors, such as the outage probability, the bit error ratio (BER), and the average channel capacity, are analysed in this paper. As compared to the conventional relay selection schemes, the impact of spectrum sensing process as well as the spectrum utilization efficiency of primary user on the performance of DF-based cognitive radio relay networks is considered. In particular, this paper has derived exact closed-form expressions for the outage probability, BER, and average capacity over independent and identically distributed (i.i.d.) Rayleigh fading channels, respectively. The proposed scheme is validated by simulations, and the analyses of closed-form expressions for some figures of merit, e.g., the outage probability, the BER and the average channel capacity, are all consistent with the outcomes of simulations. The simulations also prove that the performance of the proposed scheme is impacted considerably by some other critical parameters, such as the number of relays.

show abstract

“…The ergodic information rate for the proposed cooperative transmission is analysed in Part I [1]. The outage information rate is another useful measure to quantify the achievable performance.…”

Section: Introductionmentioning

confidence: 99%

“…Here, the outage information rate in an orthogonal frequency-division multiplexing access (OFDMA) uplink with cooperative amplify-andforward (AF) or in the decode-and-forward (DF) relaying in the presence of frequency offsets is discussed. As in Part I [1], we assume that the mobile nodes are able to transmit on one subcarrier and listen on another subcarrier simultaneously, but each node or relay cannot receive and transmit signals simultaneously on the same subcarrier, i.e. a half-duplex constraint is assumed.…”

Section: Introductionmentioning

confidence: 99%

Improved OFDMA uplink transmission via cooperative relaying in the presence of frequency offsets—Part II: Outage information rate analysis

Zhang¹,

Tellambura²,

Schober³

2009

Trans Emerging Tel Tech

Self Cite

View full text Add to dashboard Cite

SUMMARYIn Part I of this paper, the ergodic information rate is derived for an orthogonal frequency-division multiplexing access (OFDMA) uplink with cooperative relaying in the presence of frequency offsets. In this part, the outage information rate of the system is analysed. Both amplify-and-forward (AF) and decodeand-forward (DF) relays are considered. Each node can play the roles of the source node and the relay, simultaneously, at different subcarriers. Both the outage information rate and the diversity gain are derived for the interference-limited environment. Numerical results illustrate the superior performance of the proposed cooperative scheme over conventional transmission (without relaying) with regard to outage information rate.

show abstract

Improved OFDMA uplink transmission via cooperative relaying in the presence of frequency offsets—Part I: Ergodic information rate analysis

Cited by 22 publications

References 22 publications

Impact of partial relay selection on the capacity of communications systems with outdated CSI and adaptive transmission techniques

Impact of partial relay selection on the capacity of communications systems with outdated CSI and adaptive transmission techniques

Best relay selection in decode and forward cooperative cognitive radio relay networks over Rayleigh fading channels

Improved OFDMA uplink transmission via cooperative relaying in the presence of frequency offsets—Part II: Outage information rate analysis

Contact Info

Product

Resources

About