English
Related papers

Related papers: MIMO-Zak-OTFS with Superimposed Spread Pilots

200 papers

Pilot contamination remains a major bottleneck in realizing the full potential of distributed massive MIMO systems. We propose two dynamic and scalable pilot assignment schemes designed for practical deployment in such networks. First, we…

Networking and Internet Architecture · Computer Science 2025-10-27 Mohd Saif Ali Khan , Karthik RM , Samar Agnihotri

The Zak-OTFS input/output (I/O) relation is predictable and non-fading when the delay and Doppler periods are greater than the effective channel delay and Doppler spreads, a condition which we refer to as the crystallization condition. The…

Signal Processing · Electrical Eng. & Systems 2024-10-23 Jinu Jayachandran , Muhammad Ubadah , Saif Khan Mohammed , Ronny Hadani , Ananthanarayanan Chockalingam , Robert Calderbank

Millimeter-wave (mmWave) communication offers vast bandwidth for next-generation wireless systems but faces severe path loss, Doppler effects, and hardware impairments. Orthogonal Time Frequency Space (OTFS) modulation has emerged as a…

Signal Processing · Electrical Eng. & Systems 2025-11-12 Sabarinath Ramachandran , Venkatesh Khammammetti , Prasanthi Maddala , Narayan Mandayam , Ivan Seskar , Robert Calderbank

This paper addresses the problem of estimating sparse channels in massive MIMO-OFDM systems. Most wireless channels are sparse in nature with large delay spread. In addition, these channels as observed by multiple antennas in a neighborhood…

Applications · Statistics 2015-06-22 Mudassir Masood , Laila H. Afify , Tareq Y. Al-Naffouri

Accurate multiple-input multiple-output (MIMO) channel estimation is critical for next-generation wireless systems, enabling enhanced communication and sensing performance. Traditional model-based channel estimation methods suffer, however,…

Signal Processing · Electrical Eng. & Systems 2026-02-02 Seyed Alireza Javid , Nuria González-Prelcic

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

This paper addresses the intricate task of hybrid-field channel estimation in extremely large-scale MIMO (XL-MIMO) systems, critical for the progression of 6G communications. Within these systems, comprising a line-of-sight (LoS) channel…

Information Theory · Computer Science 2024-03-29 Yoonseong Kang , Hyowoon Seo , Wan Choi

Pilot contamination has been regarded as the main bottleneck in time division duplexing (TDD) multi-cell massive multiple-input multiple-output (MIMO) systems. The pilot contamination problem cannot be addressed with large-scale antenna…

Signal Processing · Electrical Eng. & Systems 2017-11-10 Xun Zou , Hamid Jafarkhani

In Zak-OTFS (orthogonal time frequency space) modulation the carrier waveform is a pulse in the delay-Doppler (DD) domain, formally a quasi-periodic localized function with specific periods along delay and Doppler. When the channel delay…

Signal Processing · Electrical Eng. & Systems 2025-07-21 Saif Khan Mohammed , Amit Kumar Pathak , Muhammad Ubadah , Ronny Hadani , Ananthanarayanan Chockalingam , Robert Calderbank

This paper proposes a novel joint channel estimation and beamforming approach for multicell wideband massive multiple input multiple output (MIMO) systems. With the proposed channel estimation and beamforming approach, we determine the…

Information Theory · Computer Science 2017-08-15 Tadilo Endeshaw Bogale , Long Bao Le , Xianbin Wang , Luc Vandendorpe

In communication systems, efficient use of the spectrum is an indispensable concern. Recently the use of compressed sensing for the purpose of estimating Orthogonal Frequency Division Multiplexing (OFDM) sparse multipath channels has been…

Information Theory · Computer Science 2015-05-28 Pooria Pakrooh , Arash Amini , Farrokh Marvasti

The precoding in cell-free massive multiple-input multiple-output (MIMO) technology relies on accurate knowledge of channel responses between users (UEs) and access points (APs). Obtaining high-quality channel estimates in turn requires the…

Information Theory · Computer Science 2021-01-27 Giovanni Interdonato , Pål Frenger , Erik G. Larsson

This paper proposes novel pilot optimization and channel estimation algorithm for the downlink multiuser massive multiple input multiple output (MIMO) system with $K$ decentralized single antenna mobile stations (MSs), and time division…

Applications · Statistics 2014-02-07 Tadilo Endeshaw Bogale , Long Bao Le

Massive MIMO is expected to play an important role in the development of 5G networks. This paper addresses the issue of pilot contamination and scalability in massive MIMO systems. The current practice of reusing orthogonal pilot sequences…

Information Theory · Computer Science 2024-09-12 Muhammad Kamran Saeed , Ahmed E. Kamal , Ashfaq Khokhar

Although the combination of the orthogonal time frequency space (OTFS) modulation and the massive multiple-input multiple-output (MIMO) technology can make communication systems perform better in high-mobility scenarios, there are still…

Information Theory · Computer Science 2021-05-21 Ding Shi , Wenjin Wang , Li You , Xiaohang Song , Yi Hong , Xiqi Gao , Gerhard Fettweis

Massive multiple-input multiple-output (MIMO) is a critical technology for future fifth-generation (5G) systems. Reduced pilot contamination (PC) enhanced system performance, and reduced inter-cell interference and improved channel…

Networking and Internet Architecture · Computer Science 2022-12-08 Qazwan Abdullah , Nor Shahida Mohd Shah , Shipun Hamzah , Adeb Salh , Mahathir Mohamad , Shahilah Nordin , Maisarah Abu , Mohammed Abdo Albaom , safwan sadeq

Although the benefits of precoding and combining of data signals are widely recognized, the potential of these techniques for pilot transmission is not fully understood. This is particularly relevant for multiuser multiple-input…

Information Theory · Computer Science 2016-11-17 Nima N. Moghadam , Hossein Shokri-Ghadikolaei , Gabor Fodor , Mats Bengtsson , Carlo Fischione

Large-scale multiple-input multiple-output (MIMO) with high spectrum and energy efficiency is a very promising key technology for future 5G wireless communications. For large-scale MIMO systems, accurate channel state information (CSI)…

Information Theory · Computer Science 2015-11-30 Zhen Gao , Linglong Dai , Zhaocheng Wang

In this paper, we consider channel estimation problem in the uplink of filter bank multicarrier (FBMC) systems. We propose a pilot structure and a joint multiuser channel estimation method for FBMC. Opposed to the available solutions in the…

Signal Processing · Electrical Eng. & Systems 2020-03-17 Hamed Hosseiny , Arman Farhang , Behrouz Farhang-Boroujeny

In this paper, we consider the problem of estimating the delay-Doppler (DD) domain input-output (I/O) relation in Zak-OTFS modulation, which is needed for signal detection. Two approaches, namely, model-dependent and model-free approaches,…

Information Theory · Computer Science 2025-10-13 Sai Pradeep Muppaneni , Vineetha Yogesh , A. Chockalingam