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Related papers: Degrees of freedom in vector interference channels

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We characterize the degrees-of-freedom (DoF) region of a class of two-unicast wireless networks under the assumption of delayed channel state information at the transmitters. We consider a layered topology with arbitrary connectivity, and…

Information Theory · Computer Science 2018-05-04 Alireza Vahid

Random beamforming (RBF) is a practically favourable transmission scheme for multiuser multi-antenna downlink systems since it requires only partial channel state information (CSI) at the transmitter. Under the conventional single-cell…

Information Theory · Computer Science 2016-11-18 Hieu Duy Nguyen , Rui Zhang , Hon Tat Hui

Interference Alignment (IA) is a transmission scheme which achieves 1/2 Degrees-of-Freedom (DoF) per transmit-antenna per user. The constraints imposed on the scheme are based on the linear receiver since conventional IA assumes Gaussian…

Information Theory · Computer Science 2014-02-12 B Hari Ram , K Giridhar

The number of degrees of freedom (NDoF) in a communication channel fundamentally limits the number of independent spatial modes available for transmitting and receiving information. Although the NDoF can be computed numerically for specific…

Signal Processing · Electrical Eng. & Systems 2025-09-23 Mats Gustafsson

We consider the MIMO (multiple-input multiple-output) Gaussian interference channel with i.i.d. fading across antennas and channel uses and with the delayed local channel state information at the transmitters (CSIT). For the two-user case,…

Information Theory · Computer Science 2015-03-19 Akbar Ghasemi , Abolfazl Seyed Motahari , Amir Keyvan Khandani

The impact of cooperation on interference management is investigated by studying an elemental wireless network, the so called symmetric interference relay channel (IRC), from a generalized degrees of freedom (GDoF) perspective. This is…

Information Theory · Computer Science 2015-05-21 Soheyl Gherekhloo , Anas Chaaban , Aydin Sezgin

In this paper, a new proof for the degrees of freedom (DoF) region of the K-user multiple-input multiple-output (MIMO) broadcast channel (BC) with no channel state information at the transmitter (CSIT) and perfect channel state information…

Information Theory · Computer Science 2014-01-27 Borzoo Rassouli , Chenxi Hao , Bruno Clerckx

We consider a $\sf K$ user interference network with general connectivity, described by a matrix $\mat{N}$, and general message flows, described by a matrix $\mat{M}$. Previous studies have demonstrated that the standard interference scheme…

Information Theory · Computer Science 2024-02-06 Yue Bi , Yue Wu , Cunqing Hua

This paper proposes a linear interference alignment (IA) scheme which can be used for uplink channels in a general multicell multiuser MIMO cellular network. The proposed scheme aims to align interference caused by signals from a set of…

Information Theory · Computer Science 2014-08-22 Khanh Pham , Kyungchun Lee

Opportunistic interference alignment (OIA) exploits channel randomness and multiuser diversity by user selection. For OIA the transmitter needs channel state information (CSI), which is usually measured on the receiver side and sent to the…

Information Theory · Computer Science 2015-05-06 Zhinan Xu , Mingming Gan , Thomas Zemen

This paper proposes an interference alignment method with distributed and delayed channel state information at the transmitter (CSIT) for a class of interference networks. The core idea of the proposed method is to align interference…

Information Theory · Computer Science 2016-11-17 Namyoon Lee , Ravi Tandon , Robert W. Heath

The optimal degree-of-freedom (DoF) region of the non-coherent multiple-access channels is still unknown in general. In this paper, we make some progress by deriving the entire optimal DoF region in the case of the two-user single-input…

Information Theory · Computer Science 2018-06-12 Khac-Hoang Ngo , Sheng Yang , Maxime Guillaud

We explore degrees of freedom (DoF) characterizations of partially connected wireless networks, especially cellular networks, with no channel state information at the transmitters. Specifically, we introduce three fundamental elements ---…

Information Theory · Computer Science 2012-03-13 Syed A. Jafar

The considered problem is that of maximizing the degrees of freedom (DoF) in cellular downlink, under a backhaul load constraint that limits the number of messages that can be delivered from a centralized controller to the base station…

Information Theory · Computer Science 2014-01-16 Aly El Gamal , Venugopal V. Veeravalli

Recent works on MIMO interference channels have shown that interference alignment can significantly increase the achievable degrees of freedom (DoF) of the network. However, most of these works have assumed a fully connected interference…

Information Theory · Computer Science 2016-08-24 Liangzhong Ruan , Vincent K. N. Lau

Interference alignment (IA) techniques mostly attain their degrees of freedom (DoF) benefits as the number of channel extensions tends to infinity. Intuitively, the more interfering signals that need to be aligned, the larger the number of…

Information Theory · Computer Science 2016-06-08 Zainalabedin Samadi , Vahid Tabataba Vakily , Farzan Haddadi

In this paper, we study the effect of the absence of channel knowledge for multiple-input-multiple-output (MIMO) networks. Specifically, we assume perfect channel state information at the receivers, no channel state information at the…

Information Theory · Computer Science 2009-09-23 Chiachi Huang , Syed A. Jafar , Shlomo Shamai , Sriram Vishwanath

We study the degrees of freedom (DoF) of MIMO two-way X relay channels. Previous work studied the case $N < 2M$, where $N$ and $M$ denote the number of antennas at the relay and each source, respectively, and showed that the maximum DoF of…

Information Theory · Computer Science 2018-02-21 Kangqi Liu , Meixia Tao , Zhengzheng Xiang , Xin Long

This paper examines the number of communication modes, that is, the degrees of freedom (DoF) in a wireless line-of-sight channel comprising a small continuous linear intelligent antenna array in the near field of a large one. The framework…

Information Theory · Computer Science 2025-07-17 Athanasios G. Kanatas , Harris K. Armeniakos , Harpreet S. Dhillon , Marco Di Renzo

We provide achievability as well as converse results for the degrees of freedom region of a MIMO $X$ channel, i.e., a system with two transmitters, two receivers, each equipped with multiple antennas, where independent messages need to be…

Information Theory · Computer Science 2007-07-13 Syed A. Jafar , Shlomo Shamai