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Robert Schober - One of the best experts on this subject based on the ideXlab platform.
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Guest Editorial: Large-Scale Multiple Antenna Wireless Systems
IEEE Journal on Selected Areas in Communications, 2013Co-Authors: Michail Matthaiou, Thomas L Marzetta, George K. Karagiannidis, Erik G. Larsson, Robert SchoberAbstract:The papers in this special issue focus on large-scale Multiple Antenna wireless systems and services.
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Multiple-Antenna techniques for wireless communications-a comprehensive literature survey
Communications …, 2009Co-Authors: Jan Mietzner, Wolfgang Gerstacker, Robert Schober, Lutz Lampe, Peter HoeherAbstract:The use of Multiple Antennas for wireless communication systems has gained overwhelming interest during the last decade - both in academia and industry. Multiple Antennas can be utilized in order to accomplish a Multiplexing gain, a diversity gain, or an Antenna gain, thus enhancing the bit rate, the error performance, or the signal-to-noise-plus-interference ratio of wireless systems, respectively. With an enormous amount of yearly publications, the field of Multiple-Antenna systems, often called Multiple-input Multiple-output (MIMO) systems, has evolved rapidly. To date, there are numerous papers on the performance limits of MIMO systems, and an abundance of transmitter and receiver concepts has been proposed. The objective of this literature survey is to provide non-specialists working in the general area of digital communications with a comprehensive overview of this exciting research field. To this end, the last ten years of research efforts are recapitulated, with focus on spatial Multiplexing and spatial diversity techniques. In particular, topics such as transmitter and receiver structures, channel coding, MIMO techniques for frequency-selective fading channels, diversity reception and space-time coding techniques, differential and non-coherent schemes, beamforming techniques and closed-loop MIMO techniques, cooperative diversity schemes, as well as practical aspects influencing the performance of Multiple-Antenna systems are addressed. Although the list of references is certainly not intended to be exhaustive, the publications cited will serve as a good starting point for further reading.
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Multilevel coding for Multiple-Antenna transmission
Proceedings IEEE International Symposium on Information Theory, 2002Co-Authors: Lutz Lampe, Robert F. H. Fischer, Robert SchoberAbstract:We consider the application of coded modulation to systems with Multiple transmit and Multiple receive Antennas. We concentrate on fast fading channels with channel state information available at the receiver only. Regarding Multiple-Antenna signaling as multi-dimensional modulation we propose to separate coding and modulation.
Bertrand M. Hochwald - One of the best experts on this subject based on the ideXlab platform.
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How much training is needed in Multiple-Antenna wireless links?
IEEE Transactions on Information Theory, 2003Co-Authors: Babak Hassibi, Bertrand M. HochwaldAbstract:Multiple-Antenna wireless communication links promise very high data rates with low error probabilities, especially when the wireless channel response is known at the receiver. In practice, knowledge of the channel is often obtained by sending known training symbols to the receiver. We show how training affects the capacity of a fading channel-too little training and the channel is improperly learned, too much training and there is no time left for data transmission before the channel changes. We compute a lower bound on the capacity of a channel that is learned by training, and maximize the bound as a function of the received signal-to-noise ratio (SNR), fading coherence time, and number of transmitter Antennas. When the training and data powers are allowed to vary, we show that the optimal number of training symbols is equal to the number of transmit Antennas-this number is also the smallest training interval length that guarantees meaningful estimates of the channel matrix. When the training and data powers are instead required to be equal, the optimal number of symbols may be larger than the number of Antennas. We show that training-based schemes can be optimal at high SNR, but suboptimal at low SNR.
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Achieving near-capacity on a Multiple-Antenna channel
IEEE Transactions on Communications, 2003Co-Authors: Bertrand M. Hochwald, Stephan Ten BrinkAbstract:Recent advancements in iterative processing of channel codes and the development of turbo codes have allowed the communications industry to achieve near-capacity on a single-Antenna Gaussian or fading channel with low complexity. We show how these iterative techniques can also be used to achieve near-capacity on a Multiple-Antenna system where the receiver knows the channel. Combining iterative processing with Multiple-Antenna channels is particularly challenging because the channel capacities can be a factor of ten or more higher than their single-Antenna counterparts. Using a "list" version of the sphere decoder, we provide a simple method to iteratively detect and decode any linear space-time mapping combined with any channel code that can be decoded using so-called "soft" inputs and outputs. We exemplify our technique by directly transmitting symbols that are coded with a channel code; we show that iterative processing with even this simple scheme can achieve near-capacity. We consider both simple convolutional and powerful turbo channel codes and show that excellent performance at very high data rates can be attained with either. We compare our simulation results with Shannon capacity limits for ergodic Multiple-Antenna channel.
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unitary space time modulation for Multiple Antenna communications in rayleigh flat fading
IEEE Transactions on Information Theory, 2000Co-Authors: Bertrand M. Hochwald, Thomas L MarzettaAbstract:Motivated by information-theoretic considerations, we propose a signaling scheme, unitary space-time modulation, for Multiple-Antenna communication links. This modulation is ideally suited for Rayleigh fast-fading environments, since it does not require the receiver to know or learn the propagation coefficients. Unitary space-time modulation uses constellations of T/spl times/M space-time signals (/spl Phi//sub i/, l=1, ..., L), where T represents the coherence interval during which the fading is approximately constant, and M
transmitter Antennas. The columns of each /spl Phi//sub i/ are orthonormal. When the receiver does not know the propagation coefficients, which between pairs of transmitter and receiver Antennas are modeled as statistically independent, this modulation performs very well either when the signal-to-noise ratio (SNR) is high or when T/spl Gt/M. We design some Multiple-Antenna signal constellations and simulate their effectiveness as measured by bit-error probability with maximum-likelihood decoding. We demonstrate that two Antennas have a 6-dB diversity gain over one Antenna at 15-dB SNR.
Prasant Mohapatra - One of the best experts on this subject based on the ideXlab platform.
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exploiting Multiple Antenna diversity for shared secret key generation in wireless networks
International Conference on Computer Communications, 2010Co-Authors: Kai Zeng, An Chan, Prasant MohapatraAbstract:Generating a secret key between two parties by extracting the shared randomness in the wireless fading channel is an emerging area of research. Previous works focus mainly on single-Antenna systems. Multiple-Antenna devices have the potential to provide more randomness for key generation than single-Antenna ones. However, the performance of key generation using Multiple-Antenna devices in a real environment remains unknown. Different from the previous theoretical work on Multiple-Antenna key generation, we propose and implement a shared secret key generation protocol, Multiple-Antenna KEy generator (MAKE) using off-the-shelf 802.11n Multiple-Antenna devices. We also conduct extensive experiments and analysis in real indoor and outdoor mobile environments. Using the shared randomness extracted from measured Received Signal Strength Indicator (RSSI) to generate keys, our experimental results show that using laptops with three Antennas, MAKE can increase the bit generation rate by more than four times over single-Antenna systems. Our experiments validate the effectiveness of using multi-level quantization when there is enough mutual information in the channel. Our results also show the trade-off between bit generation rate and bit agreement ratio when using multi-level quantization. We further find that even if an eavesdropper has Multiple Antennas, she cannot gain much more information about the legitimate channel.
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INFOCOM - Exploiting Multiple-Antenna Diversity for Shared Secret Key Generation in Wireless Networks
2010 Proceedings IEEE INFOCOM, 2010Co-Authors: Kai Zeng, An Chan, Prasant MohapatraAbstract:Generating a secret key between two parties by extracting the shared randomness in the wireless fading channel is an emerging area of research. Previous works focus mainly on single-Antenna systems. Multiple-Antenna devices have the potential to provide more randomness for key generation than single-Antenna ones. However, the performance of key generation using Multiple-Antenna devices in a real environment remains unknown. Different from the previous theoretical work on Multiple-Antenna key generation, we propose and implement a shared secret key generation protocol, Multiple-Antenna KEy generator (MAKE) using off-the-shelf 802.11n Multiple-Antenna devices. We also conduct extensive experiments and analysis in real indoor and outdoor mobile environments. Using the shared randomness extracted from measured Received Signal Strength Indicator (RSSI) to generate keys, our experimental results show that using laptops with three Antennas, MAKE can increase the bit generation rate by more than four times over single-Antenna systems. Our experiments validate the effectiveness of using multi-level quantization when there is enough mutual information in the channel. Our results also show the trade-off between bit generation rate and bit agreement ratio when using multi-level quantization. We further find that even if an eavesdropper has Multiple Antennas, she cannot gain much more information about the legitimate channel.
Marco Di Renzo - One of the best experts on this subject based on the ideXlab platform.
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System-level performance analysis of relay-aided Multiple-Antenna cellular networks
2016Co-Authors: Konstantinos Ntontin, Marco Di Renzo, Christos VerikoukisAbstract:Motivated by recent results regarding the performance analysis, in terms of coverage probability and average rate, of microwave single-Antenna cellular networks with Half-Duplex (HD) Relay Nodes (RNs) by using a stochastic-geometry approach, in this work we extend this study by considering Multiple-Antenna Base Stations (BSs) and RNs. Analytical formulas are provided for the achieved coverage probability and average rate of these networks, which are shown to closely match the simulation results. In addition, the simulation results show that the availability or not of a large Antenna array determines whether RNs can be beneficial to the network in terms of coverage improvement. In particular, substantial coverage gains are observed for a massive-Antenna deployment, whereas no rate gains are achieved due to the half-duplex constraint of the RNs.
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Spatial Modulation for Multiple-Antenna Wireless Systems : A Survey
IEEE Communications Magazine, 2011Co-Authors: Marco Di Renzo, Harald Haas, Peter GrantAbstract:Multiple-Antenna techniques constitute a key technology for modern wireless communications, which trade-off superior error performance and higher data rates for increased system complexity and cost. Among the many transmission principles that exploit Multiple-Antenna at either the transmitter, the receiver, or both, Spatial Modulation (SM) is a novel and recently proposed Multiple- uniqueness and randomness properties of the wireless channel for communication. This is achieved by adopting a simple but effective coding mechanism that establishes a one-to-one mapping between blocks of information bits to be transmitted and the spatial positions of the transmit-Antenna in the Antenna-array. In this article, we summarize the latest research achievements and outline some relevant open research issues of this recently proposed transmission technique.
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Spatial modulation for Multiple-Antenna wireless systems: A survey
IEEE Communications Magazine, 2011Co-Authors: Marco Di Renzo, Marco Di Renzo, Harald Haas, Peter M. GrantAbstract:Multiple-Antenna techniques constitute a key technology for modern wireless communications, which trade-off superior error performance and higher data rates for increased system complexity and cost. Among the many transmission principles that exploit Multiple-Antenna at either the transmitter, the receiver, or both, Spatial Modulation (SM) is a novel and recently proposed Multiple-Antenna transmission technique that can offer, with a very low system complexity, improved data rates compared to Single-Input- Single-Output (SISO) systems, and robust error performance even in correlated channel environments. SM is an entirely new modulation concept that exploits the uniqueness and randomness properties of the wireless channel for communication. This is achieved by adopting a simple but effective coding mechanism that establishes a one-to-one mapping between blocks of information bits to be transmitted and the spatial positions of the transmit-Antenna in the Antenna-array. In this article, we summarize the latest research achievements and outline some relevant open research issues of this recently proposed transmission technique.
Thomas L Marzetta - One of the best experts on this subject based on the ideXlab platform.
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Guest Editorial: Large-Scale Multiple Antenna Wireless Systems
IEEE Journal on Selected Areas in Communications, 2013Co-Authors: Michail Matthaiou, Thomas L Marzetta, George K. Karagiannidis, Erik G. Larsson, Robert SchoberAbstract:The papers in this special issue focus on large-scale Multiple Antenna wireless systems and services.
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unitary space time modulation for Multiple Antenna communications in rayleigh flat fading
IEEE Transactions on Information Theory, 2000Co-Authors: Bertrand M. Hochwald, Thomas L MarzettaAbstract:Motivated by information-theoretic considerations, we propose a signaling scheme, unitary space-time modulation, for Multiple-Antenna communication links. This modulation is ideally suited for Rayleigh fast-fading environments, since it does not require the receiver to know or learn the propagation coefficients. Unitary space-time modulation uses constellations of T/spl times/M space-time signals (/spl Phi//sub i/, l=1, ..., L), where T represents the coherence interval during which the fading is approximately constant, and M
transmitter Antennas. The columns of each /spl Phi//sub i/ are orthonormal. When the receiver does not know the propagation coefficients, which between pairs of transmitter and receiver Antennas are modeled as statistically independent, this modulation performs very well either when the signal-to-noise ratio (SNR) is high or when T/spl Gt/M. We design some Multiple-Antenna signal constellations and simulate their effectiveness as measured by bit-error probability with maximum-likelihood decoding. We demonstrate that two Antennas have a 6-dB diversity gain over one Antenna at 15-dB SNR.
