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Ascending Node
The Experts below are selected from a list of 309 Experts worldwide ranked by ideXlab platform
Tang Guojian – One of the best experts on this subject based on the ideXlab platform.

Orbit Design of SunSynchronous Satellite
Aerospace Shanghai, 2020CoAuthors: Tang GuojianAbstract:The determination method of descending/Ascending Node, longitude of Ascending Node and frozen orbit parameters for sunsynchronous orbit satellite design was analyzed on the basis of six general orbital elements. The key points of the design under the restrained conditions, such as orbit Node period, regressive cycles, regressive period, repeat period and others, were also presented. At last, an example of design for sunsynchronous, frozen and return orbit in the orbit of some satellite which altitude was 750 to 800 km was given.

The Method of MediumLow Altitude Satellite Control
Aerospace Shanghai, 2020CoAuthors: Tang GuojianAbstract:The theory derivation for inplane maneuver on semimajor axis, eccentricity and perigee argument and outplane maneuver on orbit inclination was presented in this paper. The simulation of inertial orbit capture, orbit maintenance and trim maneuver of inclination by the theory deduced was also done. The results showed that the inplane orbit maneuver with high accuracy could be realized by semimajor axis, eccentricity and perigee argument change simultaneously. Moreover, outplane inclination maneuver should be completed at perigee or apogee to influence right ascension of Ascending Node the least.
Xiaoqian Chen – One of the best experts on this subject based on the ideXlab platform.

WMNC – Traffic Prediction Based on Surrogate Model in Satellite Constellation Networks
2019 12th IFIP Wireless and Mobile Networking Conference (WMNC), 2019CoAuthors: Quan Chen, Yi Zhang, Lei Yang, Yong Zhao, Xiaoqian ChenAbstract:The traffic within the satellite coverage region varies greatly with the satellite movement. Traffic prediction in the satellite constellation networks is beneficial and necessary. The satellite coverage traffic model is formulated and the traffic prediction model is proposed with two variables: the geographic longitude of Ascending Node and the time from passing Ascending Node. In any period, all satellites in the constellation can be described by the model with these two variables. A surrogate model based prediction method is adopted to solve the traffic prediction problem with timeindependent ground traffic distribution. The simulation results show that the traffic variation is of multiple peaks and the predicted results achieve a good match with the real traffic variation.

Traffic Prediction Based on Surrogate Model in Satellite Constellation Networks
2019 12th IFIP Wireless and Mobile Networking Conference (WMNC), 2019CoAuthors: Quan Chen, Yi Zhang, Lei Yang, Yong Zhao, Xiaoqian ChenAbstract:The traffic within the satellite coverage region varies greatly with the satellite movement. Traffic prediction in the satellite constellation networks is beneficial and necessary. The satellite coverage traffic model is formulated and the traffic prediction model is proposed with two variables: the geographic longitude of Ascending Node and the time from passing Ascending Node. In any period, all satellites in the constellation can be described by the model with these two variables. A surrogate model based prediction method is adopted to solve the traffic prediction problem with timeindependent ground traffic distribution. The simulation results show that the traffic variation is of multiple peaks and the predicted results achieve a good match with the real traffic variation.
Kyle T Alfriend – One of the best experts on this subject based on the ideXlab platform.

J_2 Invariant Relative Orbits for Spacecraft Formations
Celestial Mechanics and Dynamical Astronomy, 2001CoAuthors: Hanspeter Schaub, Kyle T AlfriendAbstract:An analytic method is presented to establish J _2 invariant relative orbits. Working with mean orbit elements, the secular drift of the longitude of the Ascending Node and the sum of the argument of perigee and mean anomaly are set equal between two neighboring orbits. By having both orbits drift at equal angular rates on the average, they will not separate over time due to the J _2 influence. Two first order conditions are established between the differences in momenta elements (semimajor axis, eccentricity and inclination angle) that guarantee that the drift rates of two neighboring orbits are equal on the average. Differences in the longitude of the Ascending Node, argument of perigee and initial mean anomaly can be set at will, as long as they are setup in mean element space. For near polar orbits, enforcing both momenta element constraints may result in impractically large relative orbits. It this case it is shown that dropping the equal Ascending Node rate requirement still avoids considerable relative orbit drift and provides substantial fuel savings.

j2 invariant relative orbits for spacecraft formations
Celestial Mechanics and Dynamical Astronomy, 2001CoAuthors: Hanspeter Schaub, Kyle T AlfriendAbstract:An analytic method is presented to establish J2 invariant relative orbits. Working with mean orbit elements, the secular drift of the longitude of the Ascending Node and the sum of the argument of perigee and mean anomaly are set equal between two neighboring orbits. By having both orbits drift at equal angular rates on the average, they will not separate over time due to the J2 influence. Two first order conditions are established between the differences in momenta elements (semimajor axis, eccentricity and inclination angle) that guarantee that the drift rates of two neighboring orbits are equal on the average. Differences in the longitude of the Ascending Node, argument of perigee and initial mean anomaly can be set at will, as long as they are setup in mean element space. For near polar orbits, enforcing both momenta element constraints may result in impractically large relative orbits. It this case it is shown that dropping the equal Ascending Node rate requirement still avoids considerable relative orbit drift and provides substantial fuel savings.

J2invariant relative orbits for spacecraft formations
Celestial Mechanics and Dynamical Astronomy, 2001CoAuthors: Hanspeter Schaub, Kyle T AlfriendAbstract:An analytic method is presented to establish J2 invariant relative orbits. Working with mean orbit elements, the secular drift of the longitude of the Ascending Node and the sum of the argument of perigee and mean anomaly are set equal between two neighboring orbits. By having both orbits drift at equal angular rates on the average, they will not separate over time due to the J2 influence. Two first order conditions are established between the differences in momenta elements (semimajor axis, eccentricity and inclination angle) that guarantee that the drift rates of two neighboring orbits are equal on the average. Differences in the longitude of the Ascending Node, argument of perigee and initial mean anomaly can be set at will, as long as they are setup in mean element space. For near polar orbits, enforcing both momenta element constraints may result in impractically large relative orbits. It this case it is shown that dropping the equal Ascending Node rate requirement still avoids considerable relative orbit drift and provides substantial fuel savings.