Results 71 to 80 of about 24,730 (232)

A 3D Non‐Stationary Wideband GBSM for Low‐Altitude UAV Channels in Rail Environments

IET Microwaves, Antennas &Propagation, Volume 20, Issue 1, January/December 2026.
This paper presents a three‐dimensional (3D) wideband non‐stationary Geometry‐Based Stochastic Channel Model (GBSM) for low‐altitude unmanned aerial vehicle (UAV) communications. Distinct from existing modelling frameworks, the proposed model integrates air‐to‐air (A2A) and air‐to ground (A2G) scenarios into a generalised channel model. Moreover, a two‐
Cheng Li, Kunye Hong, Jingjing Du, Yating Gao, Pei Tang, Lei Xiong   +5 more
wiley   +1 more source

Efficient AOA Estimation and NLOS Signal Utilization for LEO Constellation-Based Positioning Using Satellite Ephemeris Information

Applied Sciences
As large-scale low Earth orbit (LEO) constellations continue to expand, the potential of their signal strength for positioning applications should be fully leveraged.
Junqi Guo, Yang Wang
doaj   +1 more source

Uplink Spectral Efficiency of Massive MIMO with Spatially Correlated Rician Fading

, 2018
This paper considers the uplink (UL) of a multi-cell Massive MIMO (multiple-input multiple-output) system with spatially correlated Rician fading channels.
Björnson, Emil, Larsson, Erik G., Özdogan, Özgecan   +2 more
core   +1 more source

Deep Reinforcement Learning Reconfigurable Smart Surface Sensing MAC Protocol for Terahertz Mesh Networks

IET Networks, Volume 15, Issue 1, January/December 2026.
This paper proposes a reconfigurable intelligent surface‐based deep reinforcement learning MAC (RIS‐DRL‐MAC) protocol for terahertz mesh networks. By embedding RIS perception into the MAC decision loop and using a distributed TD3 algorithm, the proposed scheme achieves a cross‐layer optimisation of beam direction, access timing and RIS phase control ...
Wenjian Zhang, Ping Li
wiley   +1 more source

A Multiple Scattering Channel Model for Ultraviolet Signal Propagation in the Atmosphere

IET Optoelectronics, Volume 20, Issue 1, January/December 2026.
We propose an accurate multiple scattering channel model for ultraviolet (UV) signal that propagates in the atmosphere with incorporating the variation of the refractive index structure parameter with altitude and the relative height between UV transmitter and receiver that are often ignored by the previous works.
Xianrui Jian, Qingfeng Wu
wiley   +1 more source

Experimental demonstration of non-line-of-sight visible light communication with different reflecting materials using a GaN-based micro-LED and modified IEEE 802.11ac

AIP Advances, 2018
This paper gives an experimental demonstration of non-line-of-sight (NLOS) visible light communication (VLC) using a single 80 μm gallium nitride (GaN) based micro-light-emitting diode (micro-LED).
Zhijian Lu, Pengfei Tian, Houqiang Fu, Jossue Montes, Xuanqi Huang, Hong Chen, Xiaodong Zhang, Xiaoyan Liu, Ran Liu, Lirong Zheng, Xiaolin Zhou, Erdan Gu, Yi Liu, Yuji Zhao   +13 more
doaj   +1 more source

A RSSI/PDR-Based Probabilistic Position Selection Algorithm with NLOS Identification for Indoor Localisation

ISPRS International Journal of Geo-Information, 2018
In recent years, location-based services have been receiving increasing attention because of their great development prospects. Researchers from all over the world have proposed many solutions for indoor positioning over the past several years.
Ke Han, Huashuai Xing, Zhongliang Deng, Yichen Du   +3 more
doaj   +1 more source

Comparative Study Between Measurement and Predictions Using Geometrical Optics and Uniform Theory of Diffraction for Case of Non-Line-of-Sight (NLOS) in Indoor Environment [PDF]

Wireless Personal Communications, 2012
This paper describes the investigation and comparison of the accuracy of a deterministic model for a WLAN system in the indoor environment. The measurement system consisted of a spectrum analyzer and a log-periodic antenna. Non-line-of-sight (NLOS) propagation (in furnished rooms) was investigated.
Cheng, Ee Meng, Abbas, Zulkifly, Abd Malek, Mohd Fareq, Lee, Kim Yee, You, Kok Yeow, Khor, Shing Fhan   +5 more
openaire   +2 more sources

Accurate Indoor Channel Modeling for mmWave Communication Systems in Smart Environments Using Ray Tracing and Measurement‐Based Validation

International Journal of Intelligent Systems, Volume 2026, Issue 1, 2026.
The growing requests for extremely fast indoor wireless connectivity have introduced significant challenges in designing next‐generation communication systems to build Internet of things (IoT)–enabled fully connected smart environments, particularly at higher frequency bands such as millimeter wave (mmWave/MMW).
Ling Yao, Gapar Johar, Jacquline Tham, Yurong Zhao, Mohamadreza (Mohammad) Khosravi   +4 more
wiley   +1 more source

Techniques and Advances in Ultrafast Photography

Advanced Photonics Research, Volume 6, Issue 12, December 2025.
This review maps the fast‐growing field of ultrafast photography from early mechanical cameras to modern optical‐computational methods. It organizes techniques into four families (multishot passive/active; single‐shot passive/active), explains how they reach trillion‐frame‐per‐second speeds, compares capabilities and tradeoffs, and highlights ...
Chen Huang, Xin Zhang, Renjie Han, Jiaoyu Fan, Hui Jiang, Yiwen Zhang, Jinghua Yu, Jiamin Wang, Yi Chen, Junjie Sun, Fei Chen   +10 more
wiley   +1 more source