The Experts below are selected from a list of 46302 Experts worldwide ranked by ideXlab platform
R Srikant - One of the best experts on this subject based on the ideXlab platform.
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mimo Channels in the low snr regime communication rate error exponent and signal peakiness
IEEE Transactions on Information Theory, 2007Co-Authors: R SrikantAbstract:We consider multiple-input multiple-output (MIMO) fading Channels and characterize the reliability function in the low signal-to-noise (SNR) regime as a function of the number of transmit and receive antennas. For the case when the fading matrix H has independent entries, we show that the number of transmit antennas plays a key role in reducing the peakiness in the input signal required to achieve the optimal error exponent for a given communication rate. Further, by considering a Correlated Channel model, we show that the maximum performance gain (in terms of the error exponent and communication rate) is achieved when the entries of the Channel fading matrix are fully Correlated. The results we presented in this work in the low-SNR regime can also be applied to the infinite bandwidth regime
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mimo Channels in the low snr regime communication rate error exponent and signal peakiness
Information Theory Workshop, 2004Co-Authors: R SrikantAbstract:We consider noncoherent MIMO fading Channels and characterize the reliability function in the low-SNR regime as a function of the number of transmit and receive antennas. We assume no CSI is available at the transmitter or the receiver. For the case when the fading matrix H has independent entries, we show that the number of transmit antennas plays a key role in reducing the peakiness in the input signal required to achieve the optimal error exponent for a given communication rate. Further, by considering a Correlated Channel model, we show that the maximum performance gain (in terms of the error exponent and communication rate) is achieved when the entries of the Channel fading matrix are fully Correlated.
Chanbyoung Chae - One of the best experts on this subject based on the ideXlab platform.
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relationship between cross polarization discrimination xpd and spatial correlation in indoor small cell mimo systems
IEEE Wireless Communications Letters, 2018Co-Authors: Yeongeun Lim, Yae Jee Cho, Yongshik Lee, Chanbyoung ChaeAbstract:In this letter, we provide a Correlated Channel model for a dual-polarization antenna in indoor small-cell multiple-input multiple-output (MIMO) systems. In an indoor environment, we confirm that the cross-polarization discrimination (XPD) in the direction of angle-of-departure can be represented as the spatial correlation of the MIMO Channel. We also evaluate a dual-polarization antenna-based MIMO Channel model and a spatially Correlated Channel model using a 3-D ray-tracing simulator. Furthermore, we provide the equivalent distance between adjacent antennas according to the XPD, providing insights into designing a dual-polarization antenna and its arrays.
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relationship between cross polarization discrimination xpd and spatial correlation in indoor small cell mimo systems
arXiv: Information Theory, 2017Co-Authors: Yeongeun Lim, Yae Jee Cho, Yongshik Lee, Chanbyoung ChaeAbstract:In this letter, we present a Correlated Channel model for a dual-polarization antenna to omnidirectional antennas in indoor small-cell multiple-input multiple-output (MIMO) systems. In an indoor environment, we confirm that the cross-polarization discrimination (XPD) in the direction of angle-of-departure can be represented as the spatial correlation of the MIMO Channel. We also evaluate a dual-polarization antenna-based MIMO Channel model and a spatially Correlated Channel model using a three-dimensional (3D) ray-tracing simulator. Furthermore, we provide the equivalent distance between adjacent antennas according to the XPD, providing insights into designing a dual-polarization antenna and its arrays.
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compressed Channel feedback for Correlated massive mimo systems
International Conference on Communications, 2014Co-Authors: Yeongeun Lim, Chanbyoung ChaeAbstract:In this paper, we propose compressive sensing-based Channel quantization feedback that is appropriate for practical massive multiple-input multiple-output (MIMO) systems. We assume that the base station (BS) has a compact (2-dimensional) uniform square array that has a highly Correlated Channel. To serve multiple users, the BS uses a zero-forcing precoder. Our proposed Channel feedback algorithm can reduce feedback overhead as well as a codebook search complexity. Numerical simulations confirm our analytical results.
Yeongeun Lim - One of the best experts on this subject based on the ideXlab platform.
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relationship between cross polarization discrimination xpd and spatial correlation in indoor small cell mimo systems
IEEE Wireless Communications Letters, 2018Co-Authors: Yeongeun Lim, Yae Jee Cho, Yongshik Lee, Chanbyoung ChaeAbstract:In this letter, we provide a Correlated Channel model for a dual-polarization antenna in indoor small-cell multiple-input multiple-output (MIMO) systems. In an indoor environment, we confirm that the cross-polarization discrimination (XPD) in the direction of angle-of-departure can be represented as the spatial correlation of the MIMO Channel. We also evaluate a dual-polarization antenna-based MIMO Channel model and a spatially Correlated Channel model using a 3-D ray-tracing simulator. Furthermore, we provide the equivalent distance between adjacent antennas according to the XPD, providing insights into designing a dual-polarization antenna and its arrays.
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relationship between cross polarization discrimination xpd and spatial correlation in indoor small cell mimo systems
arXiv: Information Theory, 2017Co-Authors: Yeongeun Lim, Yae Jee Cho, Yongshik Lee, Chanbyoung ChaeAbstract:In this letter, we present a Correlated Channel model for a dual-polarization antenna to omnidirectional antennas in indoor small-cell multiple-input multiple-output (MIMO) systems. In an indoor environment, we confirm that the cross-polarization discrimination (XPD) in the direction of angle-of-departure can be represented as the spatial correlation of the MIMO Channel. We also evaluate a dual-polarization antenna-based MIMO Channel model and a spatially Correlated Channel model using a three-dimensional (3D) ray-tracing simulator. Furthermore, we provide the equivalent distance between adjacent antennas according to the XPD, providing insights into designing a dual-polarization antenna and its arrays.
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compressed Channel feedback for Correlated massive mimo systems
International Conference on Communications, 2014Co-Authors: Yeongeun Lim, Chanbyoung ChaeAbstract:In this paper, we propose compressive sensing-based Channel quantization feedback that is appropriate for practical massive multiple-input multiple-output (MIMO) systems. We assume that the base station (BS) has a compact (2-dimensional) uniform square array that has a highly Correlated Channel. To serve multiple users, the BS uses a zero-forcing precoder. Our proposed Channel feedback algorithm can reduce feedback overhead as well as a codebook search complexity. Numerical simulations confirm our analytical results.
Peter M. Grant - One of the best experts on this subject based on the ideXlab platform.
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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.
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Trellis coded spatial modulation
IEEE Transactions on Wireless Communications, 2010Co-Authors: Raed Y. Mesleh, Marco Di Renzo, Harald Haas, Peter M. GrantAbstract:Trellis coded modulation (TCM) is a well known scheme that reduces power requirements without any bandwidth expansion. In TCM, only certain sequences of successive constellation points are allowed (mapping by set partitioning). The novel idea in this paper is to apply the TCM concept to the antenna constellation points of spatial modulation (SM). The aim is to enhance SM performance in Correlated Channel conditions. SM considers the multiple transmit antennas as additional constellation points and maps a first part of a block of information bits to the transmit antenna indices. Therefore, spatial multiplexing gains are retained and spectral efficiency is boosted. The second part of the block of information bits is mapped to a complex symbol using conventional digital modulation schemes. At any particular time instant, only one antenna is active. The receiver estimates the transmitted symbol and the active antenna index and uses the two estimates to retrieve the original block of data bits. In this paper, TCM partitions the entire set of transmit antennas into sub-sets such that the spacing between antennas within a particular sub-set is maximized. The scheme is called trellis coded spatial modulation (TCSM). Tight analytical performance bounds over Correlated fading Channels are proposed in this paper. In addition, the performance and complexity of TCSM is compared to the performance of SM, coded V-BLAST (vertical Bell Labs layered space-time) applying near optimum sphere decoder algorithm, and Alamouti scheme combined with TCM. Also, the performance of all schemes with turbo coded modulation is presented. It is shown that under the same spectral efficiency, TCSM exhibits significant performance enhancements in the presence of realistic Channel conditions such as Rician fading and spatial correlation (SC). In addition, the complexity of the proposed scheme is shown to be 80% less than the V-BLAST complexity.
Ender Ayanoglu - One of the best experts on this subject based on the ideXlab platform.
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precoders and equalizers for spatially Correlated antennas in single carrier massive mimo transmission
2020 International Conference on Computing Networking and Communications (ICNC), 2020Co-Authors: Nader Beigiparast, Ender AyanogluAbstract:This work presents analyses of precoders and equalizers for downlink and uplink directions with different antenna structures in a single-carrier massive MIMO transmission system for a frequency selective Gaussian multiuser Channel. Our work considers two different antenna formations and shows the performance of well-known precoders and equalizers in a spatially Correlated Channel. We show how increasing the dimension of the antenna formation can affect the system performance based on the correlation and discuss how precoding and equalizing schemes can compensate for the loss of performance due to the correlation and demonstrate the improved results.
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the effect of antenna correlation in single carrier massive mimo transmission
Vehicular Technology Conference, 2018Co-Authors: Nader Beigiparast, Gokhan M Guvensen, Ender AyanogluAbstract:This work presents a single-carrier massive MIMO transmission system for the frequency selective Gaussian multi-user Channel. It considers both cases of spatially unCorrelated and Correlated Channel and compares them in terms of the user sum-rate as well as the general performance. We consider a Channel with M antennas at the base station which provides services for K single- antenna users. We develop a general expression for the achievable rate among users in the Channel with a correlation among antennas at the base station. It has been shown that, when there is no correlation between base station antennas or users, the Channel matched filter precoder outperforms any other precoder. In a highly- Correlated massive MIMO Channel however, the conventional Channel matched filter precoder does not perform as expected. We show the failure of the Channel matched filter in the presence of a correlation pattern among antennas at the base station with theoretical analysis and simulations. We apply three different precoders to enhance the achievable rate and their performances are determined by simulations. We show that the precoders outperform the Channel matched filter in a highly-Correlated Channel with a large number of users. By increasing the number of users in the system, the conventional precoders show even better performance in terms of the user's sum- rates.
