English
Related papers

Related papers: Uplink Pre-Compensation for Ground-to-Space Optica…

200 papers

Continuous wavefront sensing on future space telescopes allows relaxation of stability requirements while still allowing on-orbit diffraction-limited optical performance. We consider the suitability of phase retrieval to continuously…

Instrumentation and Methods for Astrophysics · Physics 2023-09-14 Hyukmo Kang , Kyle Van Gorkom , Jess Johnson , Ole Singlestad , Aaron Goldtooth , Daewook Kim , Ewan S. Douglas

One of the biggest challenges in operating massive multiple-input multiple-output systems is the acquisition of accurate channel state information at the transmitter. To take up this challenge, time division duplex is more favorable thanks…

Information Theory · Computer Science 2024-10-30 Xiwen Jiang , Alexis Decurninge , Kalyana Gopala , Florian Kaltenberger , Maxime Guillaud , Dirk Slock , Luc Deneire

Transmit beamforming for underwater acoustic communication is challenging because it requires perfect knowledge of the channel to the receiver in advance. In practice, channel estimates must be learned through feedback and are often noisy…

Signal Processing · Electrical Eng. & Systems 2026-05-15 Diego A. Cuji , Andrew C. Singer , Milica Stojanovic

This paper introduces a new mathematical framework, which is used to derive joint uplink/downlink achievable rate regions for multi-user spatial multiplexing between one base station and multiple terminals. The framework consists of two…

Information Theory · Computer Science 2010-02-03 Patrick Marsch , Peter Rost , Gerhard Fettweis

Universal filtered multi-carrier (UFMC), which groups and filters subcarriers before transmission, is a potential multi-carrier modulation technique investigated for the emerging Machine-Type Communications (MTC). Considering the relaxed…

Signal Processing · Electrical Eng. & Systems 2019-02-26 Yicheng Xu , Hongyun Chu , Xiaodong Wang

Integrated sensing and communication (ISAC) has emerged as a key paradigm for next-generation wireless systems, which allows wireless resources to be used for data transmission and target sensing simultaneously. In this paper, multi-user…

Signal Processing · Electrical Eng. & Systems 2026-03-19 Ling He , Vaibhav Kumar , Roberto Bomfin , Yingyang Chen , Miaowen Wen , Marwa Chafii

Flexible intelligent metasurface (FIM) has recently received considerable interest due to its advantage in realizing a better channel condition by dynamically morphing its surface shape. An FIM consists of multiple elements deposited on a…

Information Theory · Computer Science 2026-04-01 Jinyue Jiang , Jiancheng An , Lu Gan , Naofal Al-Dhahir , Arumugam Nallanathan , Zhu Han

This paper investigates joint device activity detection and channel estimation for grant-free random access in Low-earth orbit (LEO) satellite communications. We consider uplink communications from multiple single-antenna terrestrial users…

Information Theory · Computer Science 2025-04-09 Rui Mao , Yongpeng Wu , Boxiao Shen , Symeon Chatzinotas , Björn Ottersten , Wenjun Zhang

This paper proposes a parametric channel estimation algorithm applicable to uplink of OFDMA systems with pseudo-random subchannelization. It exploits the hopping pilots to facilitate ESPRIT to estimate the delay subspace of the multipath…

Information Theory · Computer Science 2008-11-05 Xiaochuan Zhao , Tao Peng , Wenbo Wang

Although a significant number satellites are deemed essential for facilitating diverse applications of satellite networks, aerial platforms are emerging as excellent alternatives for enabling reliable communications with fewer satellites.…

Information Theory · Computer Science 2024-12-02 Chang-Sik Choi

We study uplink orthogonal frequency-division multiplexing (OFDM) pilot distortion to deliberately obfuscate time-of-arrival (ToA) estimation at a single base station while preserving communication performance. We design a complex…

Signal Processing · Electrical Eng. & Systems 2025-10-29 Mahmut Kemal Ercan , Alireza Pourafzal , Musa Furkan Keskin , Sinan Gezici , Henk Wymeersch

We have designed a plenoptic sensor to retrieve phase and amplitude changes resulting from a laser beam's propagation through atmospheric turbulence. Compared with the commonly restricted domain of (-pi, pi) in phase reconstruction by…

Optics · Physics 2023-07-19 Chensheng Wu , Jonathan Ko , Christopher C. Davis

Unmanned aerial vehicle (UAV) has become an appealing solution for a wide range of commercial and civilian applications because of its high mobility and flexible deployment. Due to the continuous UAV navigation, the channel between UAV and…

Information Theory · Computer Science 2019-11-22 Jianwei Zhao , Qi Dong , Yanjie Zhao , Bolei Wang , Feifei Gao

In this work, we study sensing-aided uplink transmission in an integrated sensing and communication (ISAC) vehicular network with the use of orthogonal time frequency space (OTFS) modulation. To exploit sensing parameters for improving…

Signal Processing · Electrical Eng. & Systems 2023-05-22 Xi Yang , Hang Li , Qinghua Guo , J. Andrew Zhang , Xiaojing Huang , Zhiqun Cheng

Tomography is an imaging technique that works by reconstructing a scene from acquired data in the form of line integrals of the imaging domain. A fundamental underlying assumption in the reconstruction procedure is the precise alignment of…

Numerical Analysis · Mathematics 2018-07-13 Toby Sanders

While more and more antennas are integrated into single mobile user equipment to increase communication quality and throughput, the number of antennas used for transmission is commonly restricted due to the concerns on hardware complexity…

Networking and Internet Architecture · Computer Science 2019-02-12 Aleksei Fedorov , Haibo Zhang , Galina Sidorenko , Bo Yang

This paper proposes a two-phase orthogonal time frequency space (OTFS)-based integrated positioning and communication (IPAC) framework under realistic low-resolution analog-to-digital converters (ADCs). In the uplink phase, the positioning…

Signal Processing · Electrical Eng. & Systems 2026-02-10 Yueyi Yang , Zeping Sui , Zilong Liu , Leila Musavian

In astronomy and microscopy, distortions in the wavefront affect the dynamic range of a high contrast imaging system. These aberrations are either imposed by a turbulent medium such as the atmosphere, by static or thermal aberrations in the…

Instrumentation and Methods for Astrophysics · Physics 2015-06-18 Benjamin Pope , Nick Cvetojevic , Anthony Cheetham , Frantz Martinache , Barnaby Norris , Peter Tuthill

Recently, reconfigurable intelligent surface (RIS) has gained research and development interests to modify wireless channel characteristics in order to improve performance of wireless communications, especially when quality of the…

Information Theory · Computer Science 2022-09-22 Alireza Salehiyan , Mohammad Javad Emadi

Though the concept of non-orthogonal multiple access (NOMA) was proposed several years ago, the performance of uplink NOMA has only been verified in theory, but not in practice. This paper presents an over-the-air implementation of a uplink…

Networking and Internet Architecture · Computer Science 2018-01-18 Samith Abeywickrama , Lei Liu , Yuhao Chi , Chau Yuen