Masoud Ardakani - Academia.edu (original) (raw)
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Papers by Masoud Ardakani
2015 IEEE International Conference on Communication Workshop (ICCW), 2015
Relay selection strategies help to improve spectral and energy efficiencies, to enhance transmiss... more Relay selection strategies help to improve spectral and energy efficiencies, to enhance transmission robustness, or to reduce latency in cooperative networks. A novel relay selection strategy, which maximizes the overall achievable sum rate, is proposed and analyzed for multiple-input multiple-output (MIMO) amplify- and-forward two-way relay networks with spatial multiplexing. Interestingly, this strategy amounts to maximizing the minimum of the determinant of the Wishart matrices from the relays to the two user nodes. The performance of this strategy is investigated by deriving the average sum rate approximations in closed-form. Our analysis and numerical results reveal that the proposed relay selection scheme provides substantial sum rate improvements.
Proceedings IEEE International Symposium on Information Theory,, 2002
... In this work we first use EXIT chart analysis to track the error rate of messages from variab... more ... In this work we first use EXIT chart analysis to track the error rate of messages from variable nodes iteration by itera-tion. ... Here p(degree = i ) is described by degree distribution and p,,,(mldegree = i) is described by EXIT chart of a regular code. ...
IEEE International Conference on Communications, 2005. ICC 2005. 2005, 2005
IEEE Communications Letters
Considering a wireless sensor network whose nodes are distributed randomly over a given area, a p... more Considering a wireless sensor network whose nodes are distributed randomly over a given area, a probability model for the network lifetime is provided. Using this model and assuming that packet generation follows a Poisson distribution, an analytical expression for the complementary cumulative density function (ccdf) of the lifetime is obtained. Using this ccdf, one can accurately find the probability that the network achieves a given lifetime. It is also shown that when the number of sensors, NNN, is large, with an error exponentially decaying with NNN, one can predict whether or not a certain lifetime can be achieved. The results of this work are obtained for both multi-hop and single-hop wireless sensor networks and are verified with computer simulation. The approaches of this paper are shown to be applicable to other packet generation models and the effect of the area shape is also investigated.
2007 IEEE International Conference on Communications, 2007
2009 IEEE International Conference on Communications, 2009
2011 IEEE Global Telecommunications Conference - GLOBECOM 2011, 2011
ABSTRACT
Theory and Applications for Narrowband and Broadband Communications over Power Lines, 2010
ABSTRACT Digital transmission is at the core of any communications system, including Power Line C... more ABSTRACT Digital transmission is at the core of any communications system, including Power Line Communications (PLC) systems. This chapter distinguishes between modulation and coding for the two classes of PLC systems, namely narrowband and broadband PLC systems. It presents a selection of modulation and coding techniques for each class. The chapter addresses modulation and coding for narrowband PLC systems. It discusses some fundamentals, permutation trellis codes-a combined coding and describes modulation scheme utilizing Frequency Shift Keying (FSK) and convolutional codes. The chapter covers both accepted modulation and coding schemes for broadband systems, as well as some more recent results. For broadband systems, the two important modulation contenders which have previously been considered include spread spectrum and multicarrier techniques. The chapter presents the latest major and arguably most powerful class of codes from information theory, namely Low-Density Parity-Check (LDPC) codes, and shows how these may be adapted for PLC. carrier transmission on power lines; frequency shift keying; modulation; parity check codes
2011 IEEE Global Telecommunications Conference - GLOBECOM 2011, 2011
ABSTRACT A novel transmit/receive (Tx/Rx) antenna selection strategy is proposed and analyzed for... more ABSTRACT A novel transmit/receive (Tx/Rx) antenna selection strategy is proposed and analyzed for two-way multiple-input multiple-output (MIMO) amplify-and-forward (AF) relay networks. This strategy involves choosing the best transmit and receive antennas at the two sources and the relay based on the minimization of the overall outage probability. The performance of the proposed selection strategy is quantified by deriving the overall outage probability and its high SNR approximation. Specifically, the diversity order is derived to obtain valuable insights into practical system designing. In particular, our results are extended to cater the multiple relay scenario, and thereby, a joint relay and Tx/Rx antenna selection strategy is proposed and analyzed. To this end, the overall outage probability, its high SNR approximation and diversity order are derived. Our numerical results show that the proposed selection strategies achieve the full diversity order. All the analyses are validated through Monte-Carlo simulations.
2012 25th IEEE Canadian Conference on Electrical and Computer Engineering (CCECE), 2012
ABSTRACT In this paper we study the problem of transmitting different quality of service (QoS) da... more ABSTRACT In this paper we study the problem of transmitting different quality of service (QoS) data classes on a broadcast erasure channel where each data class is intended for a group of users depending on their erasure rate. For real-time applications such as multimedia, data block length is typically small. Over a small data block length, the behavior of the erasure channel may significantly differ from its average. Thus, to guarantee a certain QoS, a considerable overhead may be needed. We provide a finite block length analysis of the effect of erasure on the overhead. We use this analysis to investigate a packet construction method that mitigated the effect of short block length.
ABSTRACT Two transmission strategies, namely (i) pairwise zero-forcing transmission and (ii) non-... more ABSTRACT Two transmission strategies, namely (i) pairwise zero-forcing transmission and (ii) non-pairwise zero-forcing transmission, for multiple-input multiple-output (MIMO) amplify-and-forward (AF) multi-way relay networks (MWRNs) are analytically studied. To this end, lower and upper bounds of the outage probability, the corresponding high signal-to-noise ratio outage probability approximations, the achievable sum rate, and the fundamental diversity-multiplexing trade-off are derived in closed-form. The proposed pairwise zero-forcing transmission strategy possesses a lower practical implementation complexity as each node requires only the instantaneous respective node-to-relay channel knowledge. Counter intuitively, the non-pairwise zero-forcing transmission strategy achieves higher spatial multiplexing gains over the pairwise counterpart at the expense of higher relay processing complexity and more stringent channel state information requirements. Moreover, numerical results are presented to further validate our analysis and thereby to obtain valuable insights into practical MIMO AF MWRN implementation.
2015 IEEE International Conference on Communication Workshop (ICCW), 2015
Relay selection strategies help to improve spectral and energy efficiencies, to enhance transmiss... more Relay selection strategies help to improve spectral and energy efficiencies, to enhance transmission robustness, or to reduce latency in cooperative networks. A novel relay selection strategy, which maximizes the overall achievable sum rate, is proposed and analyzed for multiple-input multiple-output (MIMO) amplify- and-forward two-way relay networks with spatial multiplexing. Interestingly, this strategy amounts to maximizing the minimum of the determinant of the Wishart matrices from the relays to the two user nodes. The performance of this strategy is investigated by deriving the average sum rate approximations in closed-form. Our analysis and numerical results reveal that the proposed relay selection scheme provides substantial sum rate improvements.
Proceedings IEEE International Symposium on Information Theory,, 2002
... In this work we first use EXIT chart analysis to track the error rate of messages from variab... more ... In this work we first use EXIT chart analysis to track the error rate of messages from variable nodes iteration by itera-tion. ... Here p(degree = i ) is described by degree distribution and p,,,(mldegree = i) is described by EXIT chart of a regular code. ...
IEEE International Conference on Communications, 2005. ICC 2005. 2005, 2005
IEEE Communications Letters
Considering a wireless sensor network whose nodes are distributed randomly over a given area, a p... more Considering a wireless sensor network whose nodes are distributed randomly over a given area, a probability model for the network lifetime is provided. Using this model and assuming that packet generation follows a Poisson distribution, an analytical expression for the complementary cumulative density function (ccdf) of the lifetime is obtained. Using this ccdf, one can accurately find the probability that the network achieves a given lifetime. It is also shown that when the number of sensors, NNN, is large, with an error exponentially decaying with NNN, one can predict whether or not a certain lifetime can be achieved. The results of this work are obtained for both multi-hop and single-hop wireless sensor networks and are verified with computer simulation. The approaches of this paper are shown to be applicable to other packet generation models and the effect of the area shape is also investigated.
2007 IEEE International Conference on Communications, 2007
2009 IEEE International Conference on Communications, 2009
2011 IEEE Global Telecommunications Conference - GLOBECOM 2011, 2011
ABSTRACT
Theory and Applications for Narrowband and Broadband Communications over Power Lines, 2010
ABSTRACT Digital transmission is at the core of any communications system, including Power Line C... more ABSTRACT Digital transmission is at the core of any communications system, including Power Line Communications (PLC) systems. This chapter distinguishes between modulation and coding for the two classes of PLC systems, namely narrowband and broadband PLC systems. It presents a selection of modulation and coding techniques for each class. The chapter addresses modulation and coding for narrowband PLC systems. It discusses some fundamentals, permutation trellis codes-a combined coding and describes modulation scheme utilizing Frequency Shift Keying (FSK) and convolutional codes. The chapter covers both accepted modulation and coding schemes for broadband systems, as well as some more recent results. For broadband systems, the two important modulation contenders which have previously been considered include spread spectrum and multicarrier techniques. The chapter presents the latest major and arguably most powerful class of codes from information theory, namely Low-Density Parity-Check (LDPC) codes, and shows how these may be adapted for PLC. carrier transmission on power lines; frequency shift keying; modulation; parity check codes
2011 IEEE Global Telecommunications Conference - GLOBECOM 2011, 2011
ABSTRACT A novel transmit/receive (Tx/Rx) antenna selection strategy is proposed and analyzed for... more ABSTRACT A novel transmit/receive (Tx/Rx) antenna selection strategy is proposed and analyzed for two-way multiple-input multiple-output (MIMO) amplify-and-forward (AF) relay networks. This strategy involves choosing the best transmit and receive antennas at the two sources and the relay based on the minimization of the overall outage probability. The performance of the proposed selection strategy is quantified by deriving the overall outage probability and its high SNR approximation. Specifically, the diversity order is derived to obtain valuable insights into practical system designing. In particular, our results are extended to cater the multiple relay scenario, and thereby, a joint relay and Tx/Rx antenna selection strategy is proposed and analyzed. To this end, the overall outage probability, its high SNR approximation and diversity order are derived. Our numerical results show that the proposed selection strategies achieve the full diversity order. All the analyses are validated through Monte-Carlo simulations.
2012 25th IEEE Canadian Conference on Electrical and Computer Engineering (CCECE), 2012
ABSTRACT In this paper we study the problem of transmitting different quality of service (QoS) da... more ABSTRACT In this paper we study the problem of transmitting different quality of service (QoS) data classes on a broadcast erasure channel where each data class is intended for a group of users depending on their erasure rate. For real-time applications such as multimedia, data block length is typically small. Over a small data block length, the behavior of the erasure channel may significantly differ from its average. Thus, to guarantee a certain QoS, a considerable overhead may be needed. We provide a finite block length analysis of the effect of erasure on the overhead. We use this analysis to investigate a packet construction method that mitigated the effect of short block length.
ABSTRACT Two transmission strategies, namely (i) pairwise zero-forcing transmission and (ii) non-... more ABSTRACT Two transmission strategies, namely (i) pairwise zero-forcing transmission and (ii) non-pairwise zero-forcing transmission, for multiple-input multiple-output (MIMO) amplify-and-forward (AF) multi-way relay networks (MWRNs) are analytically studied. To this end, lower and upper bounds of the outage probability, the corresponding high signal-to-noise ratio outage probability approximations, the achievable sum rate, and the fundamental diversity-multiplexing trade-off are derived in closed-form. The proposed pairwise zero-forcing transmission strategy possesses a lower practical implementation complexity as each node requires only the instantaneous respective node-to-relay channel knowledge. Counter intuitively, the non-pairwise zero-forcing transmission strategy achieves higher spatial multiplexing gains over the pairwise counterpart at the expense of higher relay processing complexity and more stringent channel state information requirements. Moreover, numerical results are presented to further validate our analysis and thereby to obtain valuable insights into practical MIMO AF MWRN implementation.