第一章航天器通信概述.ppt

What is Deep Space Communication Moon to earth Distance: 0.36 ~ 0.41×106km Communication Delay : 1.21 ~ 1.35s Spark (火星) to earth Distance: 59.6 ~ 401.3×106km Communication Delay : 3.3 ~ 22.3s Pluto (冥王星) to earth Distance: 4297.9 ~ 7535.1×106km Communication Delay : 3.98 ~ 6.98h * Distance and time delay between earth and planets * Space radio communication: radio communications between the spacecrafts beyond the Earths atmosphere, between the spacecraft and the earth, or between the earth stations via the spacecraft relays. Near space communication（近空通信）: radio communication between the Earth‘s entity（实体）and the spacecrafts in the satellite orbit of the Earth. Application of Satellite Manned Spacecraft * Deep Space Communications: communication between the Earth entity and the spacecraft in the space around or beyond the moon. Planet（行星）’s surface area communication Communication between the earth and planet in or outside the solar system * The main purpose of the deep communication Spacecraft Passes the information of deep space and other planets back to the Earth. Space Communication object Spacecraft: sending data, relaying data, receiving control commands. Earth station: receiving data, processing data, sending control commands. The main contents of space communication Image, sound, data. Why Deep Space Communication * Scientific Objectives of Deep Space Communication Recognizing the space environment Deep space observation Conduct scientific experiments Verify scientific hypotheses:（科学假设） Antimatter（反物质）,Magnetic monopoles（电磁极子） Space experiments: Verify gravitation Looking for new energy He-3 Landing another plant Study other planets in order to understand the Earth better Expanding frontier（疆界） to achieve interstellar migration （星际移民） * Chinas present deep space exploration activities Exploration of the moon as a starting point. Lunar （月的）exploration “Trilogy（三部曲）: around, down, back. Scientific objectives of l