Results 71 to 80 of about 17,467 (267)

Using Airborne Laser Scanning and Sentinel‐2 to Understand Subcanopy Light Regimes and Understory Diversity of Vascular Plants in Temperate Mountain Forests

Remote Sensing in Ecology and Conservation, EarlyView.
This study demonstrates that not just Airborne Laser Scanning, but also Sentinel‐2 can effectively estimate absolute canopy cover and canopy cover heterogeneity ‐ structural metrics that determine the subcanopy light regime, found to be linked to the vascular plant species richness in the understory of temperate mountain forests.
Felix Wieland‐Glasmann, Cornelius Senf, Kristin H. Braziunas, Rupert Seidl, Peter Annighöfer   +4 more
wiley   +1 more source

Tracing Three Decades of Low Earth Orbit Satellite Communication Development: A Bibliometric and Main Path Analysis of Network Architectures, Protocol Evolution, and Emerging Intelligent Services

International Journal of Satellite Communications and Networking, EarlyView.
ABSTRACT Low Earth Orbit (LEO) satellite communication systems have evolved into a critical component of global broadband networks, enabling wide‐area connectivity, IoT services, and intelligent multilayer satellite–terrestrial integration. Despite rapid advancements in constellation deployment, routing mechanisms, resource management, and LEO–5G/6G ...
Wei‐Hao Su, Ya‐Chen Chuang, Long‐Sheng Chen   +2 more
wiley   +1 more source

Improved Short-Term Clock Prediction Method for Real-Time Positioning

Sensors, 2017
The application of real-time precise point positioning (PPP) requires real-time precise orbit and clock products that should be predicted within a short time to compensate for the communication delay or data gap. Unlike orbit correction, clock correction
Yifei Lv, Zhiqiang Dai, Qile Zhao, Sheng Yang, Jinning Zhou, Jingnan Liu   +5 more
doaj   +1 more source

Role, path, and vision of “5G + BDS/GNSS”

Satellite Navigation, 2020
Communication, positioning, navigation, and decision-making abilities have evolved into Positioning, Navigation, and Timing (PNT) intelligence during the long process of human migration and hence promoted human evolution.
Jingnan Liu, Kefu Gao, Wenfei Guo, Jingsong Cui, Chi Guo   +4 more
doaj   +1 more source

Low‐Complexity Hybrid Beamforming for LEO Satellites: Beam Update Rate Analysis and Advanced Adaptive Precoding

International Journal of Satellite Communications and Networking, EarlyView.
ABSTRACT Low Earth Orbit (LEO) satellite constellations offer unprecedented opportunities for global broadband connectivity but pose significant beamforming challenges due to rapid platform motion and stringent onboard hardware constraints. Fully digital architectures, while optimal in theory, remain impractical for satellite payloads, motivating ...
Mohammad Momani, Thomas Delamotte, Andreas Knopp   +2 more
wiley   +1 more source

2D LiDAR SLAM Back-End Optimization with Control Network Constraint for Mobile Mapping

Sensors, 2018
Simultaneous localization and mapping (SLAM) has been investigated in the field of robotics for two decades, as it is considered to be an effective method for solving the positioning and mapping problem in a single framework.
Jingren Wen, Chuang Qian, Jian Tang, Hui Liu, Wenfang Ye, Xiaoyun Fan   +5 more
doaj   +1 more source

Dynamic Cell Division for Interference Management in Satellite Direct‐to‐Cell Systems

International Journal of Satellite Communications and Networking, EarlyView.
ABSTRACT Direct‐to‐cell (D2C) connectivity enables future non‐terrestrial networks to provide service directly to standard terrestrial user equipment (UE) when terrestrial networks (TN) are unavailable. In this work, the satellite system is considered as a secondary network that supplements existing TN coverage while minimizing interference to the ...
Satya Chan, Hee Wook Kim, Bon‐Jun Ku, Daesub Oh   +3 more
wiley   +1 more source

National BDS Augmentation Service System (NBASS) of China: Progress and Assessment

Remote Sensing, 2017
: In this contribution, the processing strategies of real-time BeiDou System (BDS) precise orbits, clocks, and ionospheric corrections in the National BDS Augmentation Service System (NBASS) are briefly introduced.
Chuang Shi, Fu Zheng, Yidong Lou, Shengfeng Gu, Weixing Zhang, Xiaolei Dai, Xianjie Li, Hailin Guo, Xiaopeng Gong   +8 more
doaj   +1 more source

Integrating Image Segmentation and Deep Learning to Improve Radio Frequency Propagation Models

International Journal of Satellite Communications and Networking, EarlyView.
ABSTRACT This paper proposes a multi‐sensor approach to improve radio frequency (RF) propagation models, which play a key role in the rapidly expanding field of connected vehicle technology. Focusing on the 1‐ to 20‐GHz frequency range, which is critical for both satellite‐to‐vehicle and base station‐to‐vehicle communications, our study introduces a ...
Jonathan Israel, Xavier Boulanger, Vegard Arneson   +2 more
wiley   +1 more source

Characteristics of BeiDou-3 Experimental Satellite Clocks

Remote Sensing, 2018
The characteristics of the improved Atomic Frequency Standard (AFS) operated on the latest BeiDou-3 experimental satellites are analyzed from day-of-year (DOY) 254 to 281, of the year 2017, considering the following three aspects: stability, periodicity,
Yifei Lv, Tao Geng, Qile Zhao, Jingnan Liu   +3 more
doaj   +1 more source