关键词：通信；空中运输；空中交通控制；飞机通信；地空通信
摘 要：Identify existing technologies being used for air-to-air and air-to-ground communications. Identify relevant technologies that may mature and be applicable to future air-to-air or air-to-ground communications within the study 50 year time horizon. Identify and characterize communication candidates functional attributes and characteristics. Identify initial requirements for air-to-air / air-to-ground comm. to support future anticipated NextGen applications and map/assess the ability of the candidates to support Air Traffic Management (ATM) applications. Identify ground and airborne architectural and infrastructure needs of the candidates. Identify vulnerabilities and security challenges with comm. candidates and outline mitigation methods.