Results 21 to 30 of about 311,790 (337)

Investigating the Test and Evaluation of GaN Transistors Radiation Resistance in SSPA Amplifier Board in LEO Satellite Payload [PDF]

فصلنامه علوم و فناوری فضایی, 2023
With the advent of GaN technology, achieving microwave power with high efficiency by solid-state devices has become more available. Therefore, the use of SSPA amplifiers with GaN technology in satellites, especially LEO satellites, has been considered ...
Roghieh Karimzadeh Baee, Hamideh Daneshvar, Amir Hossin Ahmadi, Parvin Sojoodi   +3 more
doaj   +1 more source

Experimental Demonstration of High-Security and Low-CSPR Single-Sideband Transmission System Based on 3D Lorenz Chaotic Encryption

Photonics
Broadcast-style downlinks (e.g., PONs and satellites) expose physical waveforms despite transport-layer cryptography, motivating physical-layer encryption (PLE).
Chao Yu, Angli Zhu, Hanqing Yu, Yuanfeng Li, Mu Yang, Peijin Hu, Haoran Zhang, Xuan Chen, Hao Qi, Deqian Wang, Yiang Qin, Xiangning Zhong, Dong Zhao, Yue Liu   +13 more
doaj   +1 more source

Design of Satellite Operations Subsystem Using Dynamic Fault Management Mechanism [PDF]

Journal of Astronomy and Space Sciences, 1998
Satellite Operations Subsystem in the Mission Control Element provides real-time monitoring of the satellite status and transmits telecommands to control the satellite during the contact time.
Jaehoon Kim, Heesook Mo, Woonchan Jung
doaj  

Design and Implementation of Hitl Simulator Coupleing Communications Payload and Software Spacecraft Bus [PDF]

Journal of Astronomy and Space Sciences, 2003
Engineering qualification model payload for a communications and broadcasting satellite(CBS) was developed by ETRI from May, 2000 to April, 2003. For the purpose of functional test and verification of the payload, a real-time hardware-in-the-loop(HITL ...
In-Jun Kim, Wan-Sik Choi
doaj   +1 more source

NORAD TLE Type Orbit Determination of LEO Satellites Using GPS Navigation Solutions [PDF]

Journal of Astronomy and Space Sciences, 2002
NORAD Two Line Elements (TLE) are widely used for the increasing number of small satellite mission operations and analysis. However, due to the irregular periodicity of generation of the NORAD TLE, a new TLE that is independent of NORAD is required.
Chang-Hwa Cho, Byoung-Sun Lee, Jeong-Sook Lee, Jae-Hoon Kim, Kyu-Hong Choi   +4 more
doaj   +1 more source

Africa: cyber-security and its mutual impacts with computerisation, miniaturisation and location-based authentication

EAI Endorsed Transactions on Mobile Communications and Applications, 2017
The state of insecurity occasioned by fraudulent practices in Africa has been of concern economically, both at home and abroad. In this paper, we propose ways to mitigate this problem, using Nigeria as a case study.
M.I. Adeka, K.O.O. Anoh, M. Ngala, S.J. Shepherd, E. Ibrahim, I.T.E. Elfergani, A.S. Hussaini, J. Rodriguez, R.A. Abd-Alhameed   +8 more
doaj   +1 more source

Communications satellite technology [PDF]

, 1964
Communications satellite technology - echo, relay, and syncom ...
Hedrich, A. L.
core   +1 more source

3D (Bio) Printing Combined Fiber Fabrication Methods for Tissue Engineering Applications: Possibilities and Limitations

Advanced Functional Materials, EarlyView.
Biofabrication aims at providing innovative technologies and tools for the fabrication of tissue‐like constructs for tissue engineering and regenerative medicine applications. By integrating multiple biofabrication technologies, such as 3D (bio) printing with fiber fabrication methods, it would be more realistic to reconstruct native tissue's ...
Waseem Kitana, Indra Apsite, Leonid Ionov   +2 more
wiley   +1 more source

Quantum Emitters in Hexagonal Boron Nitride: Principles, Engineering and Applications

Advanced Functional Materials, EarlyView.
Quantum emitters in hexagonal boron nitride have emerged as a promising candidate for quantum information science. This review examines the fundamentals of these quantum emitters, including their level structures, defect engineering, and their possible chemical structures.
Thi Ngoc Anh Mai, Md Shakhawath Hossain, Nhat Minh Nguyen, Yongliang Chen, Chaohao Chen, Xiaoxue Xu, Quang Thang Trinh, Toan Dinh, Toan Trong Tran   +8 more
wiley   +1 more source

Analytical Study on Mission Control Element System Availability for Korea Multipurpose Satellite (KOMPSAT) I [PDF]

Journal of Astronomy and Space Sciences, 1998
To estimate the availability of the MCE for KOMPSAT I, mathematical models of H/W and S/W availability, the availability estimating methods for parallel and redundant system were presented. Furthermore, to improve and estimate the MCE system availability,
J. W. Eun, D. I. Chang, J. M. Kim
doaj