English
Related papers

Related papers: Channel-Adaptive Pilot Design for FDD-MIMO Systems…

200 papers

We study downlink channel estimation in a frequency-division duplex (FDD) massive MIMO system from PMI-only feedback under a 5G NR-type limited-feedback architecture. In this architecture, the user selects a preferred codeword from a shared…

Information Theory · Computer Science 2026-04-27 Jinchi Chen , Mingxi Hu , Peigang Jiang , Xin Meng , Ke Wei , Xianyin Zhang

The increasing number of users leads to an increase in pilot overhead, and the limited pilot resources make it challenging to support all users using orthogonal pilots. By fully capturing the inherent physical characteristics of the…

Signal Processing · Electrical Eng. & Systems 2025-01-07 Kaiyuan Tian , Yani Chi , Yufan Zhou , An Liu

We derive novel bounds for the performance of algorithms that estimate the downlink covariance matrix from the uplink covariance matrix in frequency division duplex (FDD) massive multiple-input multiple-output (MIMO) systems. The focus is…

Signal Processing · Electrical Eng. & Systems 2018-08-02 Renato Luis Garrido Cavalcante , Lorenzo Miretti , Slawomir Stanczak

Massive MIMO systems can achieve high spectrum and energy efficiency in downlink (DL) based on accurate estimate of channel state information (CSI). Existing works have developed learning-based DL CSI estimation that lowers uplink feedback…

Information Theory · Computer Science 2022-05-31 Yu-Chien Lin , Ta-Sung Lee , Zhi Ding

The 3GPP suggests to combine dual polarized (DP) antenna arrays with the double directional (DD) channel model for downlink channel estimation. This combination strikes a good balance between high-capacity communications and parsimonious…

Signal Processing · Electrical Eng. & Systems 2018-10-29 Cheng Qian , Xiao Fu , Nicholas D. Sidiropoulos , Ye Yang

Suppose a linear model y = Hx + n, where inputs x, n are independent Gaussian mixtures. The problem is to design the transfer matrix H so as to minimize the mean square error (MSE) when estimating x from y. This problem has important…

Optimization and Control · Mathematics 2015-06-11 John T. Flåm , Dave Zachariah , Mikko Vehkaperä , Saikat Chatterjee

The doubly selective (DS) channel estimation in the large-scale multiple-input multiple-output (MIMO) systems is a challenging problem due to the large number of the channel coefficients to be estimated, which requires unaffordable and…

Signal Processing · Electrical Eng. & Systems 2020-04-22 Bo Gong , Lin Gui , Qibo Qin , Xiang Ren , Wen Chen

We study downlink (DL) channel estimation in a multi-cell Massive multiple-input multiple-output (MIMO) system operating in a time-division duplex. The users must know their effective channel gains to decode their received DL data signals.…

Information Theory · Computer Science 2021-09-07 Amin Ghazanfari , Trinh Van Chien , Emil Björnson , Erik G. Larsson

An adaptive bandwidth selection procedure for the mixture kernel in the maximum mean discrepancy (MMD) for fitting generative moment matching networks (GMMNs) is introduced, and its ability to improve the learning of copula random number…

Machine Learning · Statistics 2025-09-01 Marius Hofert , Gan Yao

A framework for adaptive and non-adaptive statistical compressive sensing is developed, where a statistical model replaces the standard sparsity model of classical compressive sensing. We propose within this framework optimal task-specific…

Computer Vision and Pattern Recognition · Computer Science 2015-06-03 Julio M. Duarte-Carvajalino , Guoshen Yu , Lawrence Carin , Guillermo Sapiro

Diffusion models are distinguished by their exceptional generative performance, particularly in producing high-quality samples through iterative denoising. While current theory suggests that the number of denoising steps required for…

Machine Learning · Computer Science 2025-04-08 Gen Li , Changxiao Cai , Yuting Wei

Channel estimation and beamforming play critical roles in frequency-division duplexing (FDD) massive multiple-input multiple-output (MIMO) systems. However, these two modules have been treated as two stand-alone components, which makes it…

Signal Processing · Electrical Eng. & Systems 2021-08-04 Yifan Ma , Yifei Shen , Xianghao Yu , Jun Zhang , S. H. Song , Khaled B. Letaief

Millimeter wave (mmWave) multi-user massive multi-input multi-output (MIMO) is a promising technique for the next generation communication systems. However, the hardware cost and power consumption grow significantly as the number of radio…

Signal Processing · Electrical Eng. & Systems 2021-06-09 Liangyuan Xu , Feifei Gao , Ting Zhou , Shaodan Ma , Wei Zhang

Image compression is a fundamental research field and many well-known compression standards have been developed for many decades. Recently, learned compression methods exhibit a fast development trend with promising results. However, there…

Image and Video Processing · Electrical Eng. & Systems 2020-03-31 Zhengxue Cheng , Heming Sun , Masaru Takeuchi , Jiro Katto

Multidimensional Index Modulations (IM) are a novel alternative to conventional modulations which can bring considerable benefits for future wireless networks. Within this scope, in this paper we present a new scheme, named as…

Signal Processing · Electrical Eng. & Systems 2021-08-09 Vasco Velez , Joao Pedro Pavia , Nuno Souto , Pedro Sebastiao , Americo Correia

We derive an asymptotic expansion for the log likelihood of Gaussian mixture models (GMMs) with equal covariance matrices in the low signal-to-noise regime. The expansion reveals an intimate connection between two types of algorithms for…

Statistics Theory · Mathematics 2020-06-30 Anya Katsevich , Afonso Bandeira

In this paper, we propose a study of performance of the channel estimation using LS, MMSE, LMMSE and Lr-LMMSE algorithms in OFDM (Orthogonal Frequency Division Multiplexing) system which, as known suffers from the time variation of the…

Other Computer Science · Computer Science 2012-02-09 Aida Zaier , Ridha Bouallegue

In an aerial hybrid massive multiple-input multiple-output (MIMO) and orthogonal frequency division multiplexing (OFDM) system, how to design a spectral-efficient broadband multi-user hybrid beamforming with a limited pilot and feedback…

Signal Processing · Electrical Eng. & Systems 2022-09-12 Zhen Gao , Minghui Wu , Chun Hu , Feifei Gao , Guanghui Wen , Dezhi Zheng , Jun Zhang

Massive multiple-input multiple-output (mMIMO) regime reaps the benefits of spatial diversity and multiplexing gains, subject to precise channel state information (CSI) acquisition. In the current communication architecture, the downlink…

Information Theory · Computer Science 2022-08-26 Muhammad Karam Shehzad , Luca Rose , Stefan Wesemann , Mohamad Assaad , Syed Ali Hassan

Efficient channel state information at transmitter (CSIT) for frequency division duplex (FDD) massive MIMO can facilitate its backward compatibility with existing FDD cellular networks. To date, several CSIT estimation schemes have been…

Information Theory · Computer Science 2021-08-24 Yikun Mei , Zhen Gao