• Optimisation of power allocation for asymmetric relay placement in multi-hop relay systems 

  Dhaka, Kalpana; Mallik, Ranjan K.; Schober, Robert (Institution of Engineering and Technology, 2013-04)

  In this study, schemes for optimisation of power allocation (OPA) for asymmetric relay placement are presented for multi-hop communication in a Rayleigh-fading environment. For a decode-and-forward (DF) multi-hop communication ...
• Joint power allocation and relay selection in energy harvesting AF relay systems 

  Ahmed, Imtiaz; Ikhlef, Aissa; Schober, Robert; Mallik, Ranjan K. (IEEE, 2013-04)

  In this letter, we propose joint relay selection and power allocation schemes for maximization of the throughput of an amplify-and-forward (AF) cooperative communication system where the source and the relays are energy ...
• Beamforming and combining in two-way AF MIMO relay networks 

  Arti, M.K.; Mallik, Ranjan K.; Schober, Robert (IEEE, 2013-07)

  In this letter, we propose a beamforming and combining scheme for a two-way amplify-and-forward (AF) multiple-input multiple-output (MIMO) relay network. An approximate expression for the symbol error rate of the scheme ...
• WLAN service providers' price competition with uncertainty in user demand 

  Kumar, Abhinav; Mallik, Ranjan K.; Schober, Robert (IEEE, 2013-03)

  In this letter, uncertainty in users' network selection is modeled by a Markov chain. In the presence of such uncertainty, the price competition game of wireless local area network (WLAN) service providers (SPs) is analyzed ...
• Sensing time and power optimization in MIMO Cognitive Radio Networks 

  Moghimi, Farzad; Mallik, Ranjan K.; Schober, Robert (IEEE, 2012-09)

  In this paper, we investigate the sensing-throughput tradeoff in multi-antenna cognitive radio (CR) systems. Specifically, we optimize the sensing threshold, sensing time, and transmit power of a multi-input multi-output ...
• Network coded multi-source cooperative communication in BICM-OFDM Networks 

  Islam, Toufiqul; Nasri, Amir; Schober, Robert; Mallik, Ranjan K.; Bhargava, Vijay K. (IEEE, 2012-09)

  In this paper, we study a cooperative diversity scheme for wireless systems employing network coding and the combination of bit-interleaved coded modulation (BICM) and orthogonal frequency division multiplexing (OFDM). The ...
• Relay subset selection and fair power allocation for best and partial relay selection in generic noise and interference 

  Ahmed, Imtiaz; Nasri, Amir; Michalopoulos, Diomidis S.; Schober, Robert; Mallik, Ranjan K. (IEEE, 2012-05)

  Best relay selection (BRS) has received considerable attention in the literature as it makes efficient use of the system resources and achieves full diversity. Partial relay selection (PRS) is an alternative to BRS and ...
• Asymptotic performance of generalized selection combining in generic noise and fading 

  Ahmed, Imtiaz; Nasri, Amir; Schober, Robert; Mallik, Ranjan K. (IEEE, 2012-04)

  In this letter, we investigate the performance of generalized selection combining in channels impaired by generalized fading and generic noise with finite moments. In particular, we derive accurate high signal-to-noise ...
• Performance analysis of decode-and-forward multi-hop communication : a difference equation approach 

  Dhaka, Kalpana; Mallik, Ranjan K.; Schober, Robert (IEEE, 2012-02)

  The presence of multiple users between signal transmission source and destination enables division of long links into multiple shorter links; this reduces signal attenuation, extends battery life, and provides broader and ...
• Asymptotic Performance of Lp-Norm MIMO Detection 

  Ahmed, I.; Schober, R; Mallik, R K (2010)

  Full search L1-norm (FS-L1) and sphere decoding L∞-norm (SD-L∞) detectors have been previously proposed for multiple-input multiple-output (MIMO) systems as they entail a lower receiver complexity than the optimal L2-norm ...
• Cooperative BICM-OFDM: Sub-carrier and power allocation 

  Islam, T; Schober, R; Mallik, R K; Bhargava, V K (2010)

  In this paper, we consider amplify-and-forward cooperative diversity for wireless systems employing bit-interleaved coded modulation (BICM) and orthogonal frequency division multiplexing (OFDM). In the second hop, multiple ...
• Network Coded Cooperative BICM-OFDM 

  Islam, T; Nasri, A; Schober, R; Mallik, R K; Bhargava, V K (2011)

  In this paper, we study a cooperative diversity scheme for wireless systems employing network coding and the combination of bit-interleaved coded modulation (BICM) and orthogonal frequency division multiplexing (OFDM). The ...
• Analysis and relay placement for DF cooperative BICM-OFDM systems 

  Islam, T; Nasri, A; Schober, R; Mallik, R K (2011)

  In this paper, we study a decode-and-forward cooperative diversity scheme for wireless systems using the combination of bit-interleaved coded modulation (BICM) and orthogonal frequency division multiplexing (OFDM). We ...
• Amplify-and-Forward Cooperative Diversity for BICM-OFDM Systems 

  Islam, T; Schober, R; Mallik, R K; Bhargava, V K (2010)

  In this paper, we propose a novel amplify-and- forward cooperative diversity scheme for wireless systems using the combination of bit-interleaved coded modulation (BICM) and orthogonal frequency division multiplexing (OFDM). ...
• Hybrid Coherent/Energy Detection for Cognitive Radio Networks 

  Moghimi, F; Schober, R; Mallik, R K (2010)

  Cognitive radio (CR) networks require reliable spectrum sensing techniques in order to avoid interference to the primary users of the spectrum. Most existing spectrum sensing techniques are based on simple energy detection. ...
• SEP of a scaled selection combining scheme with decode and forward relaying for MPSK signaling 

  Selvaraj, M D; Mallik, R K (2010-07)

  The performance analysis of a cooperative diversity system with decode and forward relaying has drawn considerable attention recently. The use of conventional maximal-ratio combiners does not suit well for a cooperative ...
• Single-Relay Cooperative Diversity with Scaled Selection Combining 

  Selvaraj, M D; Mallik, R K (2011)

  For a single-relay cooperative diversity system employing the decode-and-forward protocol in Rayleigh fading, a scaled signal-to-noise ratio-based selection combining scheme, which uses a deterministic scale factor for ...
• Scaled Selection Combining Based Cooperative Diversity System With Decode and Forward Relaying 

  Selvaraj, M D; Mallik, R K (2010)

  Consider a cooperative diversity network that consists of a source, cooperating relays, and a destination. The relays cooperate with the source through the decode and forward protocol to transmit a data symbol from the ...
• Hybrid Coherent/Energy Detection for Cognitive Radio Networks 

  Moghimi, F; Schober, R; Mallik, R K (2011)

  Cognitive radio (CR) networks require reliable spectrum sensing in order to avoid interference to the primary users of the spectrum. Most existing spectrum sensing techniques are based on simple energy detection. However, ...
• Performance Analysis of a Multi-Relay Cooperative Diversity Network with Decode and Forward Relaying 

  Selvaraj, M D; Mallik, R K (IEEE, 2010-01)

  Consider a multi-relay cooperative diversity network consisting of a source, N relays, and a destination. For the transmission of a data symbol from the source to the destination, the re- lays cooperate with the source ...

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