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IEEE OPEN JOURNAL OF THE COMMUNICATIONS SOCIETY 2020年 1卷 713-731页

作者： Illi, Elmehdi El Bouanani, Faissal Ayoub, Fouad Alouini, Mohamed-Slim Mohammed V Univ ENSIAS Coll Engn Rabat 10000 Morocco CRMEF Dept Comp Engn Kenitra 14000 Morocco King Abdullah Univ Sci & Technol Comp Elect & Math Sci & Engn Div Thuwal 23955 Saudi Arabia

Hybrid terrestrial-satellite (HTS) communication systems have gained a tremendous amount of interest recently due to the high demand for global high data rates. Conventional satellite communications operate in the conventional Ku (12 GHz) and Ka (26.5-40 GHz) radio-frequency bands for assessing the feeder link, between the ground gateway and the satellite. Nevertheless, with the aim to provide hundreds of Mbps of throughput per each user, free-space optical (FSO) feeder links have been proposed to fulfill these high data rates requirements. In this paper, we investigate the physical layer security performance for a hybrid very high throughput satellite communication system with an FSO feeder link. In particular, the satellite receives the incoming optical wave from an appropriate optical ground station, carrying the data symbols of N users through various optical apertures and combines them using the selection combining technique. Henceforth, the decoded and regenerated information signals of the N users are zero-forcing (ZF) precoded in order to cancel the interbeam interference at the end-users. The communication is performed under the presence of malicious eavesdroppers nodes at both hops. Statistical properties of the signal-to-noise ratio of the legitimate and wiretap links at each hop are derived, based on which the intercept probability metric is evaluated. The derived results show that above a certain number of optical apertures, the secrecy level is not improved further. Also, the system's secrecy is improved using ZF precoding compared to the no-precoding scenario for some specific nodes' positions. All the derived analytical expressions are validated through Monte Carlo simulations.

关键词： Free-space optics high-throughput communications hybrid terrestrial-satellite systems intercept probability optical feeder links physical layer security zero-forcing precoding

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Low-high SNR transition in multiuser MIMO

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ELECTRONICS LETTERS 2015年第3期51卷 296-U98页

作者： Egan, M. Czech Tech Univ Fac Elect Engn CR-16635 Prague Czech Republic

Multiuser multiple-input-multiple-out (MU-MIMO) plays a key role in the widely adopted 3GPP LTE standard for wireless cellular networks. Although exact and asymptotic sum-rate results are well known, the problem of obtaining intuitive analytical results for medium signal-to-noise ratios (SNRs) is still not solved. As a result of the present reported work, the bend point is proposed, which quantifies the transition between low and high SNR, i.e. the beginning of the high SNR region. The bend point is derived for MU-MIMO with zero-forcing precoding and is obtained, that it is intimately related to the intercept of the high SNR asymptote with the zero sum-rate line. Using this result, a new approximation of the sum-rate at the bend point it is shown providing a useful rule of thumb for the effect of increasing the number of antennas at medium SNR.

关键词： 3G mobile communication Long Term Evolution MIMO communication cellular radio precoding 3GPP LTE standard MU MIMO antennas asymptotic sum-rate bend point exact sum-rate low-high SNR transition medium signal-to-noise ratios multiuser multiple-input and multiple-out system wireless cellular networks zero sum-rate line zero-forcing precoding

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Downlink Transmission Scheme Based on Virtual Cell Merging in Ultra Dense Networks 84

Downlink Transmission Scheme Based on Virtual Cell Merging i...

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84th IEEE Vehicular Technology Conference (VTC-Fall)

作者： Xiao, Chiyang Zeng, Jie Su, Xin Wang, Jing Xu, Xibin Ge, Lu Zhang, Li Tsinghua Univ Res Inst Informat Technol Tsinghua Natl Lab Informat Sci & Technol Beijing Peoples R China

ISBN: (纸本)9781509017010

Ultra dense network (UDN) is identified as one of the key enablers for 5G since it can provide ultra high spectral reuse factor exploiting proximal transmissions. By densifying the network infrastructure equipments, it's highly possible that each user will have one or more dedicated serving base station antennas, introducing the user-centric virtual cell paradigm. However, due to irregular deployment of large amount of base station antennas, the interference environment becomes rather complex, thus introducing severe interferences among different virtual cells. This paper focuses on the downlink transmission scheme in UDN where a large number of users and base station antennas are uniformly spread over a certain area. An interference graph is first created based on the large-scale fadings. Then, base station antennas and users in the virtual cells within the same maximal connected component are grouped together and merge into one new virtual cell cluster, where users are jointly served via zeroforcing beamforming. A multi-virtual-cell minimum mean square error precoding scheme is further proposed to mitigate the inter-cluster interference. Simulation results show that the proposed interference graph based virtual cell merging approach can attain the average user rate performance of the grouping scheme based on virtual cell overlapping with smaller virtual cell size and reduced signal processing complexity.

关键词： Ultra dense networks virtual cell interference graph zero-forcing precoding multi-virtual-cell minimum mean square error precoding

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Centralized Single FPGA Real Time zero forcing Massive MIMO 5G Basestation Hardware and Gateware 21

Centralized Single FPGA Real Time Zero Forcing Massive MIMO ...

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21st IEEE International Workshop on Signal Processing Advances in Wireless Communications (IEEE SPAWC)

作者： Benzin, Andreas Osterland, Dennis Dill, Maksim Caire, Giuseppe Tech Univ Berlin Commun & Informat Theory Chair Einsteinufer 25 D-10587 Berlin Germany

ISBN: (纸本)9781728154787

In the following a massive MIMO 5G < 6 GHz base station implementation is presented which is capable of real-time zero forcing precoding on a single central signal processing (CSP) FPGA. The built prototype is capable of simultaneously driving M = 196 separate RF ports all delivering samples to the CSP FPGA. Each RF chain's ADCs and DACs are running at 40 MSPS at full roll-out. The power consumption of the remote radio head is 1.56 W per RF port when running at a sample rate of 15.36 MSPS. The system allows for hardware-in-the-loop operation and real-time baseband signal processing with a round trip delay of 278 mu s when processing 64 antennas and 8 simultaneous user streams for an 5 GNR-like OFDMA system with 1024 sub-carriers and 50 resource blocks (600 used subcarriers) with a sample frequency of 15.36 MHz and a central signal processing clock of 184.32 MHz. The reciprocity calibration system runs completely internal to the system and doesn't radiate signals for the calibration procedure. Furthermore the central single-FPGA signal processing architecture allows for simplified implementation of algorithms and maintenance of the system.

关键词： Massive MIMO massive SDR 5G New Radio zero-forcing precoding FPGA real-time baseband signal processing low-latency precoding

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Phase Index-Based Receive Spatial Modulation PHY Security Against Supervised Pattern Recognition

Phase Index-Based Receive Spatial Modulation PHY Security Ag...

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IEEE Wireless Communications and Networking Conference (WCNC)

作者： Abushattal, Abdelrahman Arslan, Huseyin Istanbul Medipol Univ Dept Elect & Elect Engn Istanbul Turkey Univ S Florida Dept Elect Engn Tampa FL USA

ISBN: (纸本)9781728195056

Receive Spatial Modulation (RSM) uses the index of the receive antenna to convey additional information bits, which reduces the receiver complexity and improves spectral efficiency. Additionally, it provides inherent physical layer security using the zero-forcing (ZF) precoding technique. However, the channel becomes vulnerable to eavesdropper (Eve) if the channel impulse response is assumed to be time-invariant or stationary through coherent block intervals. In this paper, a physical layer secure scheme is proposed based on phase index RSM to combat eaves-droppers that use k-nearest neighbors (KNN) supervised pattern recognition. The average bit error rate (BER) performance shows the ability of the proposed scheme to provide a suitable level of security while degrading the average BER performance of Eve.

关键词： Multi-input Multi-output k-nearest neighbors (KNN) zero-forcing precoding supervised pattern recognition receive spatial modulation physical-layer security supervised Pattern Recognition

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Performance of Limited Feedback MU-MIMO in Distributed Antenna Systems with Different Schedulers

Performance of Limited Feedback MU-MIMO in Distributed Anten...

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IEEE 11th Malaysia International Conference on Communications (MICC)

作者： Behjati, Mehran Ismail, Mahamod Ibrahim, Muhammad Univ Kebangsaan Malaysia Dept Elect Elect & Syst Engn Ukm Bangi 43600 Selangor Malaysia Univ Teknol MARA Fac Elect Engn Shah Alam 40450 Selangor Malaysia

ISBN: (纸本)9781479915323

Distributed antenna system (DAS) acts as an effective solution to mitigating interference and path-loss by decreasing the access distance for users, and increases the cell coverage and system capacity as well. This study evaluates performance of scheduling methods on the DAS where practical system constraints are considered, such as path-loss, out-of-cell interference and limited feedback. zero-forcing multiuser MIMO precoding is utilized as downlink transmission strategy, when imperfect channel state information is available at the transmitter. System performance is evaluated by empirical cumulative density functions of the cell throughput, where a long-term evolution advanced (LTE-A) standard compliant simulator is utilized for simulation. It is demonstrated that by spreading the transmit antennas throughout the cell more cell throughput is achievable. Moreover, by utilizing an appropriate scheduling algorithm, more potential of DAS can be extracted and leads to substantial cell throughput.

关键词： distributed antenna system limited feedback zero-forcing precoding user scheduling

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QoS Guaranteed Resource Allocation in Cooperative Cellular Network With MIMO-Based Relays

QoS Guaranteed Resource Allocation in Cooperative Cellular N...

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IEEE International Conference on Communications (ICC)

作者： Phuyal, Umesh Jha, Satish C. Bhargava, Vijay K. Univ British Columbia Vancouver BC V5Z 1M9 Canada

ISBN: (纸本)9781612842332

Relay-based cooperative transmission in cellular wireless networks has been an area of tremendous research recently. Since multiple-input multiple-output (MIMO) technique has been shown to increase the spectral efficiency significantly, relays with MIMO antennas seem to be potential candidates for future cooperative cellular system in order to achieve reliable transmission, high system throughput and extended network coverage. In this paper, we study a cellular system scenario where quality of service of multiple data streams originating from a base station (BS) targeted to multiple mobile stations (MSs) is guaranteed by using pre-installed relay stations (RSs) with MIMO antennas. We propose a low-complexity algorithm to design precoder matrices at BS and RS by using joint zero-forcing strategy to avoid multiuser interference in the signal received at the MSs via both the direct path (BS-MS) and the relay path (BS-RS-MS). The proposed algorithm guarantees a predefined signal-to-noise ratio at each user within the transmit power constraint at BS and with the minimal sum transmit power of BS and RS. Simulation results show that proposed algorithm outperforms the singular value decomposition (SVD)-based scheme existing in the literature by keeping the outage probability lower. Moreover, the performance of proposed algorithm compared to that of SVD-based scheme is further improved when the RS is not situated directly between the BS and the MSs.

关键词： Cellular network cooperative communication MIMO relay power allocation quality of service system outage zero-forcing precoding

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Receive antenna selection in the downlink of multiuser MIMO systems 62

Receive antenna selection in the downlink of multiuser MIMO ...

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62nd IEEE Vehicular Technology Conference

作者： Wu, YL Zhang, JF Zheng, HB Xu, XB Zhou, SD Tsinghua Univ Dept Elect Engn Natl Lab Informat Sci & Technol Beijing 100084 Peoples R China

ISBN: (纸本)0780391527

In this paper, we introduce the idea of the antenna selection to the downlink of a multiuser MIMO system. The antenna selection method could not only solve one potential dimensional problem in the zero-forcing (ZF) preprocessing of the downlink, but also obtain more diversity benefits without increasing the hardware cost. An optimal selection algorithm is given based on the sum capacity, and a suboptimal but faster algorithm is proposed based on an asymptotic lower bound of the capacity. Simulation is employed to show its effectiveness.

关键词： multiuser MIMO receive antenna selection zero-forcing precoding

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Capacity of Distributed Millimetre-wave Antenna Arrays 21

Capacity of Distributed Millimetre-wave Antenna Arrays

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IEEE Statistical Signal Processing Workshop (SSP)

作者： Islam, Shammi Farhana Burr, Alister Grace, David Univ York Dept Elect Engn York YO10 5DD N Yorkshire England

ISBN: (纸本)9781728157672

Enhanced mobile broadband (eMBB) wireless communications in 5G and beyond will use millimetre-wave bands because of the bandwidth available, but this will require multi-element arrays to provide the antenna gain required to overcome the path loss in these bands. In this paper we consider the use of multiple arrays to provide distributed beamforming to serve multiple users, using a simplified precoding approach based on zero forcing to avoid inter-user interference. We also consider the effect of Ricean fading using a simple ring-of-scatterers model, and show that the Rice factor observed by the user is increased due to the effect of beamforming

关键词： Distributed massive MIMO millimeter-wave zero-forcing precoding Ricean fading

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Distributed UAV-enabled zero-forcing cooperative jamming scheme for safeguarding future wireless networks 32

Distributed UAV-enabled zero-forcing cooperative jamming sch...

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32nd IEEE Annual International Symposium on Personal, Indoor and Mobile Radio Communications (IEEE PIMRC)

作者： Cabezas, X. A. Flores Osorio, D. P. Moya Latva-aho, M. Univ Oulu Ctr Wireless Commun Oulu Finland

ISBN: (纸本)9781728175867

In this work, we investigate the impact of two cooperative unmanned aerial vehicle (UAV)-based jammers on the secrecy performance of a ground wireless network in the presence of an eavesdropper. For that purpose, we investigate the secrecy-area related metrics, Jamming Coverage and Jamming Efficiency. Moreover, we propose a hybrid metric, the so-called Weighted Secrecy Coverage (WSC) and a virtual distributed multiple-input-multiple-output (MIMO)-based zero-forcing precoding scheme to avoid the jamming effects on the legitimate receiver. For evaluating these metrics, we derive a closed-form position-based metric, the secrecy improvement. Our mathematical derivations and comparative simulations show that the proposed zero-forcing scheme leads to an improvement on the secrecy performance in terms of the WSC, and provides conditions for improvement of Jamming Efficiency. They also show positioning trends on the UAVs over a fixed orbit around the legitimate transmitter as well as power allocation trends for optimal secrecy.

关键词： cooperative jamming physical layer security UAV communications zero-forcing precoding

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