发展空—地数据链面临的问题

70年代ARINC和SITA公司建立了为航空公司运营服务的空—地VHF数据链,采用面向字符协议.其机载设备分别为ACARS和AIRCOM,两家公司分别在全球建立了地面通信网路.新CNS/ATM系统所定义的空—地数据链不论通信的物理手段用卫星、VHF或S模式,均在面向位的协议下,可以在航空电信网(ATN)中互连传送.任何一个国家发展空—地数据链时都面临着选择,应考虑是迁就旧体制发展面向字符的网路,还是一步到位地直接发展面向位的网络.

Some Issues Faced in Developing the Air - Ground Data -link

: The VHF air-ground data-links first established in the 1970s by ARINC and SUA for airline operation services are brought into use by means of character-oriented protocols. Its airborne equipment is ACARS and AIRCOM respectively. The global ground communication networks are built up by the two firms separately. But the air-ground data-links defined by the new CNS/ATM system, whether their physical means of communication is satellite, VHP or mode-s, can all be inter and intra-transmitted through the ATNs under the bit-oriented protocols. In the development of their air-ground data-links all countries have two alternatives open to them: either to develop a character-oriented network on the basis of the existing system or directly to set up a brand-new bit-oriented network.