English
Related papers

Related papers: Grassmannian Beamforming for MIMO Amplify-and-Forw…

200 papers

Unicast communication over a network of $M$-parallel relays in the presence of an eavesdropper is considered. The relay nodes, operating under individual power constraints, amplify and forward the signals received at their inputs. The…

Information Theory · Computer Science 2015-04-21 Siddhartha Sarma , Samar Agnihotri , Joy Kuri

We consider a multipair decode-and-forward relay channel, where multiple sources transmit simultaneously their signals to multiple destinations with the help of a full-duplex relay station. We assume that the relay station is equipped with…

Information Theory · Computer Science 2014-05-07 Hien Quoc Ngo , Himal A. Suraweera , Michail Matthaiou , Erik G. Larsson

Distributed transmit beamforming is a technique that adjusts the signals from cooperating radios to combine coherently at a destination radio. To achieve coherent combining, the radios can exchange preambles with the destination for…

Signal Processing · Electrical Eng. & Systems 2022-05-11 Samer Hanna , Danijela Cabric

Relaying techniques for millimeter-wave wireless networks represent a powerful solution for improving the transmission performance. In this work, we quantify the benefits in terms of delay and throughput for a random-access multi-user…

Networking and Internet Architecture · Computer Science 2019-03-08 Cristian Tatino , Nikolaos Pappas , Ilaria Malanchini , Lutz Ewe , Di Yuan

In this work, a relay channel is studied in which a source encoder communicates with a destination decoder through a number of out-of-band relays that are connected to the decoder through capacity-constrained digital backhaul links. This…

Information Theory · Computer Science 2013-04-16 Seok-Hwan Park , Osvaldo Simeone , Onur Sahin , Shlomo Shamai

We consider a multi-pair relay channel where multiple sources simultaneously communicate with destinations using a relay. Each source or destination has only a single antenna, while the relay is equipped with a very large antenna array. We…

Information Theory · Computer Science 2016-11-18 Himal A. Suraweera , Hien Quoc Ngo , Trung Q. Duong , Chau Yuen , Erik G. Larsson

It is well-known that the problem of finding the optimal beamformers in massive multiple-input multiple-output (MIMO) networks is challenging because of its non-convexity, and conventional optimization based algorithms suffer from high…

Information Theory · Computer Science 2020-11-10 Minghe Zhu , Tsung-Hui Chang , Mingyi Hong

The present paper studies the asymptotic performance of multi-hop amplify-and-forward relay multiple-antenna communication channels. Each multi-antenna terminal in the network amplifies the received signal, sent by a source, and retransmits…

Information Theory · Computer Science 2016-06-24 Maksym A. Girnyk , Mikko Vehkaperä , Lars K. Rasmussen

Accurate channel estimation is critical to fully exploit the beamforming gains when communicating with extremely large aperture arrays. The propagation distances between the user and receiver, which potentially has thousands of…

Signal Processing · Electrical Eng. & Systems 2024-02-01 Alva Kosasih , Özlem Tuğfe Demir , Emil Björnson

The integration of terahertz communications and ultra-massive multiple-input multiple-output (UM-MIMO) systems in 6G networks is motivated by their ability to enable unprecedented data rates, mitigate spectrum congestion, and enhance…

Signal Processing · Electrical Eng. & Systems 2026-05-14 Dmitry Artemasov , Alexander Shmatok , Kirill Andreev , Alexey Frolov , Manjesh K. Hanawal , Nikola Zlatanov

We address the problem of a multi-user relay network, where multiple single-antenna node pairs want to exchange information by using a multiple antenna relay node. Due to the half-duplex constraint of the relay, the exchange of information…

Information Theory · Computer Science 2010-12-23 Aydin Sezgin , Holger Boche , Amir Salman Avestimehr

This paper investigates the transmit beamforming design for multiple-input multiple-output systems to support both multi-target localization and multi-user communications. To enhance the target localization performance, we derive the…

Signal Processing · Electrical Eng. & Systems 2025-01-14 Bo Tang , Da Li , Wenjun Wu , Astha Saini , Prabhu Babu , Petre Stoica

In many wireless communication applications, it is desirable to transmit the same data to multiple user equipments (UEs). Physical layer multicasting presents an efficient transmission topology to exploit the beamforming capabilities at the…

Signal Processing · Electrical Eng. & Systems 2025-09-30 Mahmoud Zaher , Emil Björnson , Marina Petrova

Large-scale MIMO systems can yield a substantial improvement in spectral efficiency for future communication systems. Due to the finer spatial resolution achieved by a huge number of antennas at the base stations, these systems have shown…

Information Theory · Computer Science 2014-10-15 Abla Kammoun , Axel Müller , Emil Björnson , Mérouane Debbah

The focus of this paper is on multi-user MIMO transmissions for millimeter wave systems with a hybrid precoding architecture at the base-station. To enable multi-user transmissions, the base-station uses a cell-specific codebook of…

Information Theory · Computer Science 2018-07-04 Miguel R. Castellanos , Vasanthan Raghavan , Jung H. Ryu , Ozge H. Koymen , Junyi Li , David J. Love , Borja Peleato

Controlling the radar beam-pattern by optimizing the transmit covariance matrix is a well-established approach for performance enhancement in multiple-input-multiple-output (MIMO) radars. In this paper, we investigate the joint optimization…

Signal Processing · Electrical Eng. & Systems 2022-08-10 Arindam Bose , Shahin Khobahi , Mojtaba Soltanalian

We translate the problem of designing a secure communications protocol for several users communicating through a relay in a wireless network into understanding certain subvarieties of products of Grassmannians. We calculate the dimension of…

Information Theory · Computer Science 2015-02-24 Arsenia Chorti , Ragnar Freij , David Karpuk

Symbiotic radio (SR) backscatter systems are possible techniques for the future low-power wireless communications for Internet of Things devices. In this paper, we propose a multiple-input-multiple-output (MIMO) SR backscatter system, where…

Information Theory · Computer Science 2019-07-15 Tuo Wu , Miao Jiang , Qi Zhang , Quanzhong Li , Jiayin Qin

The knowledge of receiver beam shapes is essential for accurate radio interferometric imaging. Traditionally, this information is obtained by holographic techniques or by numerical simulation. However, such methods are not feasible for an…

Instrumentation and Methods for Astrophysics · Physics 2013-07-19 Sarod Yatawatta

The beamforming techniques have been recently studied as possible enablers for underlay spectrum sharing. The existing beamforming techniques have several common limitations: they are usually system model specific, cannot operate with…

Information Theory · Computer Science 2015-04-27 Daniel Denkovski , Valentin Rakovic , Vladimir Atanasovski , Liljana Gavrilovska , Petri Mähönen