Results 81 to 90 of about 86,758,594 (170)

The Satellite Downlink Replanning Problem: A BP Neural Network and Hybrid Algorithm Approach for IoT Internet Connection

IEEE Access, 2018
In the era of the Internet of Things, the role of a satellite has become increasingly important. The use of satellite resources can meet the needs of high-speed Internet connection of the Internet of Things. Effective communication between satellites and
Yan-Jie Song, Bing-Yu Song, Zhong-Shan Zhang, Ying-Wu Chen   +3 more
doaj   +1 more source

Satellite high speed downlink packet access physical layer performance analysis

, 2020
The high speed downlink packet access (HSDPA) system has been investigated for adaptation in the GEO satellite environment in order to achieve high packet user throughput and system efficiency.
Azizan, A, Quddus, AU, Evans, BG
core   +1 more source

Passive Metasurface-Based Low Earth Orbit Ground Station Design

Tsinghua Science and Technology
Low Earth Orbit (LEO) satellite communication is vital for wireless systems. The main challenges in designing LEO satellite ground stations include increasing the input signal strength to counteract severe path loss, and adaptively steering the direction
Hao Pan, Lili Qiu
doaj   +1 more source

Large Along-Track Baseline SAR-GMTI: First Results With The TerraSAR-X/TanDEM-X Satellite Constellation [PDF]

, 2011
In the paper first ground moving target indication (GMTI) and parameter estimation results obtained with the spaceborne TerraSAR-X/TanDEM-X satellite constellation are presented and discussed.
Baumgartner, Stefan V., Stefan V. Baumgartner, Krieger, Gerhard, Gerhard Krieger   +3 more
core   +1 more source

Hyperspectral Image Segmentation for Optimal Satellite Operations: In-Orbit Deployment of 1D-CNN

Remote Sensing
AI on spaceborne platforms optimizes operations and increases automation, crucial for satellites with limited downlink capacity. It can ensure that only valuable information is transmitted, minimizing resources spent on unnecessary data, which is ...
Jon Alvarez Justo, Dennis D. Langer, Simen Berg, Jens Nieke, Radu Tudor Ionescu, Per Gunnar Kjeldsberg, Tor Arne Johansen   +6 more
doaj   +1 more source

Performance analysis of satellite-to-ground downlink optical communications with spatial diversity over Gamma–Gamma atmospheric turbulence

, 2015
The performances of satellite-to-ground downlink optical communications over Gamma–Gamma distributed turbulence are studied for a multiple-aperture receiver system.
Ma, Jing, Yu, Siyuan, Li, Kanging, Belmonte Molina, Aniceto, Tan, Liying   +4 more
core   +1 more source

DORSAL: Downlink Optimization for Robust Direct-to-Satellite LoRaWAN

International audienceDelivering downlink ACKs to Class A LoRaWAN devices via LEO satellite constellations requires predicting end-to-end propagation delays of 10–500 ms to hit a 1-second receive window, a timing challenge absent from terrestrial ...
Souza, Richard Demo, Valois, Fabrice, Rivano, Hervé, Diaz, Marcos, Azurdia-Meza, Cesar, Fraire, Juan, Sánchez, Samuel Montejo, Dujovne, Diego, Hernandez, Carlos Fernandez, Iova, Oana, Gaitán, Miguel Gutiérrez   +10 more
core   +1 more source

TET-1 SATELLITE OPERATIONS LESSONS LEARNED: PREPARATION OF MISSION, LEOP AND ROUTINE OPERATIONS OF 11 DIFFERENT EXPERIMENTS [PDF]

, 2011
TET-1 is a small experimental satellite with 11 different space experiments on-board. Built by German space industry it’s a satellite dedicated to verification of newly developed space hardware and software. The German Space Operations Center (GSOC) as
Gude, Julian, Mühlbauer, Peter, Axmann, Robert   +2 more
core  

Downlink MBER transmit beamforming design based on uplink MBER receive beamforming for rank-deficient TDD-SDMA systems

, 2010
The downlink minimum bit error rate (MBER) transmit beamforming is directly designed based on the uplink MBER receive beamforming solution for time division duplex (TDD) space-division multiple-access (SDMA) induced multiple-input multiple-output (MIMO ...
Yang, Lie-Liang, Chen, Sheng
core   +1 more source

Quantum BER estimation modelling and analysis for satellite‐based quantum key distribution scenarios

IET Quantum Communication
The quantum communication channel is considered to be eavesdropped when the signal Quantum Bit Error Rate (QBER) exceeds a defined theoretical limit and is thus considered a figure of merit parameter for assessing the security of a quantum channel.
Abhishek Khanna, Sambuddha Majumder, Adarsh Jain, Dinesh Kumar Singh   +3 more
doaj   +1 more source