What are Keplerian elements?
The correct answer is A: Parameters that define the orbit of a satellite. What Keplerian elements are parameters that define the orbit of a satellite. Keplerian elements describe the orbital parameters needed to predict satellite position. For amateur radio operators, this is important for satellite tracking. Understanding this helps when tracking satellites.
Exam Tip
Keplerian elements = parameters that define orbit of satellite. Think 'K'eplerian 'E'lements = 'K'ey 'E'lements for orbit. Keplerian elements describe the orbital parameters needed to predict satellite position. Not Yagi elements, not magnetron filaments, not encryption codes - just orbital parameters.
Memory Aid
"Keplerian elements = parameters that define orbit of satellite. Think 'K'eplerian 'E'lements = 'O'rbit 'E'lements. Keplerian elements describe the orbital parameters needed to predict satellite position. Important for satellite tracking."
Real-World Application
Keplerian elements: They are parameters that define the orbit of a satellite, such as inclination, eccentricity, right ascension of ascending node, etc. These elements are used to calculate where a satellite will be at any given time. This is what Keplerian elements are - orbital parameters for satellite tracking.
Key Concepts
Why Other Options Are Wrong
Option B: Incorrect. Phase reversing elements in Yagi antenna aren't Keplerian elements - Keplerian elements are orbital parameters, not antenna elements. Yagi elements aren't Keplerian.
Option C: Incorrect. High-emission heater filaments in magnetron tubes aren't Keplerian elements - Keplerian elements are orbital parameters, not tube components. Magnetron filaments aren't Keplerian.
Option D: Incorrect. Encrypting codes for spread spectrum modulation aren't Keplerian elements - Keplerian elements are orbital parameters, not encryption codes. Encryption codes aren't Keplerian.
题目解析
The correct answer is A: Parameters that define the orbit of a satellite. What Keplerian elements are parameters that define the orbit of a satellite. Keplerian elements describe the orbital parameters needed to predict satellite position. For amateur radio operators, this is important for satellite tracking. Understanding this helps when tracking satellites.
考试技巧
Keplerian elements = parameters that define orbit of satellite. Think 'K'eplerian 'E'lements = 'K'ey 'E'lements for orbit. Keplerian elements describe the orbital parameters needed to predict satellite position. Not Yagi elements, not magnetron filaments, not encryption codes - just orbital parameters.
记忆口诀
Keplerian elements = parameters that define orbit of satellite. Think 'K'eplerian 'E'lements = 'O'rbit 'E'lements. Keplerian elements describe the orbital parameters needed to predict satellite position. Important for satellite tracking.
实际应用示例
Keplerian elements: They are parameters that define the orbit of a satellite, such as inclination, eccentricity, right ascension of ascending node, etc. These elements are used to calculate where a satellite will be at any given time. This is what Keplerian elements are - orbital parameters for satellite tracking.
错误选项分析
Option B: Incorrect. Phase reversing elements in Yagi antenna aren't Keplerian elements - Keplerian elements are orbital parameters, not antenna elements. Yagi elements aren't Keplerian. Option C: Incorrect. High-emission heater filaments in magnetron tubes aren't Keplerian elements - Keplerian elements are orbital parameters, not tube components. Magnetron filaments aren't Keplerian. Option D: Incorrect. Encrypting codes for spread spectrum modulation aren't Keplerian elements - Keplerian elements are orbital parameters, not encryption codes. Encryption codes aren't Keplerian.
知识点
Keplerian elements, Parameters, Orbit of satellite, Satellite tracking
Verified Content
Question from official FCC Extra Class question pool. Explanation reviewed by licensed amateur radio operators.