The R&D in satellite communications in Korea has been driven mainly by KCC (Korea Communications Commission) but in a small scale compared to Korea space development program organized by MEST (Ministry of Education, Science and Technology). Public and civilian satcom sector R&D has been led mainly by ETRI with small/medium companies contrary to rare investment in private sector while military s...

In the present work a new concept of satellite-based navigation system, which does not require on-board atomic references, is presented. This novel concept consists of a constellation of compact low-earth orbit positioning satellites that are equipped with on-board steerable clocks, i.e. voltage controlled crystal oscillator (VCXO). An appropriate ground-satellite synchronization network is res...

Rural America Telemedicine requires very high bandwidth to provide timely transmission of large data sets. These resources may take decades to appear because of the economics of low population densities and costly installation, and the historically low rate of bandwidth improvement available from the common communication providers. Satellites provide the natural choice for communication between...

AThis paper introduces the development of a ground experiment testbed for synthetic mission demonstration of small satellites in National University of Defense Technology (NUDT). This testbed consists of five parts: test platform, small satellite simulator, monitoring and control system, data collecting and simulation system, and displaying system. It can simulate small satellite motion with tw...

We use the first data set from ground-based TEC and scintillation receiver located at Norwegian Research Station Troll in Queen Maud Land, Antarctica to analyze detail ionospheric response during geomagnetic disturbances on February 26–27 March 18–19, 2018. By combining with complementary measurements (scintillation receivers, magnetometers, SuperDARN, DMSP satellites), we demonstrate that plas...

In this paper, we describe the Earth observation mission we have been working on, including its requirements in terms of autonomy. Then, we describe the decision problem to manage, the reactive/deliberative architecture we used for on-line decision-making, the decision rules used by the reactive part, and the iterated stochastic greedy search used by the deliberative part. Finally, we present r...

this paper develops new results on the use of model predictive control to regulate the attitude of a ground station antenna. two degree of freedom az-el pedestal is considered as ground station antenna. permanent magnet synchronous motors are taken into consideration as the best choice for satisfaction of control objectives as actuators. the design is based on a two cascade controller consist o...

Page 1 of 43 The timing of associative memory formation: Frontal lobe and anterior medial temporal 1 lobe activity at associative binding predicts memory 2 3 J. B. Hales 4 J. B. Brewer 5 6 Department of Neurosciences, Radiology at the University of California, San Diego, CA, USA 7 8 9 Running Title: Activity at the time of binding predicts associative memory 10 11 Corresponding author: 12 James...

We propose and study a decentralized formation flying control architecture based on the evolutionary robotic technique. We develop our control architecture for the MIT SPHERES robotic platform on board the International Space Station and we show how it is able to achieve micrometre and microradians precision at the path planning level. Our controllers are homogeneous across satellites and do no...