So sánh phương pháp

	TCAS	Lan truyền SGP4 TLE
Lĩnh vực	Hàng không vũ trụ	Hàng không vũ trụ
Họ	Process / pipeline	Process / pipeline
Năm ra đời	1989	1970s
Người khởi xướng	FAA, ICAO	NORAD, USAF
Loại	Avionics system	Propagation method
Công trình gốc	Federal Aviation Administration (2017). Traffic Collision Avoidance System (TCAS II). Technical Standard Order TSO-C119c.	Vallado, D. A., Crawford, P., Hujsa, R., & Kelso, T. S. (2006). Revisiting Spacetrack Report Number 3. In AIAA/AAS Astrodynamics Specialist Conference.
Tên gọi khác	TCAS II, ACAS, traffic avoidance	SGP4, TLE propagation, simplified perturbations
Liên quan	3	3
Tóm tắt	TCAS (Traffic Collision Avoidance System) is an airborne safety system that detects nearby aircraft using radar and mode C altitude reports, then provides traffic advisories (TAs) and recommended collision avoidance maneuvers (RAs) to flight crews. Mandated globally on commercial aircraft since 2000, TCAS is considered a last line of defense against mid-air collisions. TCAS II is the most common variant; TCAS I is a simplified advisory-only version for general aviation.	SGP4 (Simplified General Perturbations 4) is a rapid orbital propagation method that predicts satellite position and velocity from Two-Line Element (TLE) sets published by NORAD. Developed in the 1970s, SGP4 accounts for atmospheric drag, gravitational perturbations, and solar radiation pressure using simplified analytical models. SGP4 is the de facto standard for space surveillance, conjunction assessment, and satellite tracking.