Firstly, this paper expounds the development status of automatic forwarding system in civil aviation communication technology, analyzes the interconnection scheme of automatic forwarding system, and discusses the rationality of automatic forwarding system in combination with the actual work of civil aviation communication, so as to provide reference for related research fields.
Keywords: civil aviation; Wired communication; Automatic forwarding; network interface
The rapid development of information technology has promoted the progress of civil aviation communication technology, especially wired communication and wireless communication, which have been widely used in the field of computer information technology. Automatic forwarding technology plays an important role in China civil aviation system and will play a greater role in the future civil aviation communication system. Based on this, this paper focuses on the application of automatic forwarding system in civil aviation communication technology.
1 development status of automatic forwarding system in civil aviation communication technology
The main data of the civil aviation automatic transmission network are obtained from the data network of the regional air traffic control bureau and the civil aviation data information communication network, and the civil aviation satellite network is used as the transmission medium to form the data automatic transmission system. At present, the automatic telegraph relay system of Lhasa Gongga Airport is responsible for the professional telegraph relay between the airport in the region and domestic and international civil aviation airports, such as control, meteorology, navigation information, passenger and cargo transportation, etc. , access to Chengdu telegraph relay, access to regional airports, departmental business terminals, wide business coverage, high communication reliability requirements. The existing automatic forwarding system in Lhasa Airport adopts DMHS-M medium-sized automatic forwarding system developed and produced by Beijing Air Traffic Control Technology Co., Ltd., which is equipped with 64-way forwarding interfaces and adopts 4 intelligent asynchronous units. Its remote service terminals include Chengdu ATM, Chengdu Satellite, Chengdu Dialing, Linzhi Dialing, Ali ATM, Ali Dialing, Bangda ATM, Bangda Satellite, Bangda Dialing, Shigatse ATM and Shigatse Dialing.
2 automatic transmission system interconnection scheme
2. 1 asynchronous interconnection transmission system mode
The civil aviation relay system mostly adopts direct connection mode, which needs to occupy multiple physical ports, and the communication speed and transmission reliability are not high. In addition, it is necessary to maintain and rent multiple communication lines at the same time, which leads to high economic cost and poor economy. The mature information transmission mode of civil aviation is asynchronous interconnection, which can be chosen as a reliable backup scheme because of its strong compatibility.
2.2X.25 transmission mode
X.25 transmission is the main transmission mode in civil aviation telegraph system, but the throughput is not high, which can basically meet the requirements of character communication business in civil aviation telegraph. At present, the transmission scheme applied in trunk relay system is SVC technology. In the process of realizing information interconnection, the chain is mainly established through temporary calling or using constant connection. Any port in the system can realize 128 SVC, which can easily meet the interconnection of multiple systems. Combined with the development of civil aviation forwarding system, X.25 protocol was developed earlier. Based on the existing network transmission structure, considering the situation of expanding network certificate, this method has high cost and unsatisfactory communication speed. The highest standard before 2 1 century was only 64K. In the automatic telegraph relay system of China civil aviation communication technology, the main interfaces of trunk system interconnection are ACARS telegraph exchange, AFTN international interface, Terez, SITA international interface, Y_CABLE, China aerotelegraph interface and the connection between Air China Eastern Airlines telegraph relay system and air traffic control system. These interfaces all use X.25 when transmitting data information, but X.25 is not the mainstream transmission technology. After the data network is expanded, the civil aviation department will no longer provide special direct connection equipment through X.25 ..
2.3IP interconnection
In the civil aviation data network, IP scheme can well realize the data transmission of forwarding system, whether in technical realization or operation management. First of all, it is simple and feasible to use IP technology programming to realize information transmission. TCP and UDP can be used for data transmission, and the civil aviation intelligent synchronous control system is a router provided by aviation management technology. It is easy to realize the interconnection transmission between ATM network and KU satellite network and transmit it in the automatic transmission system under OSPF protocol. For OSPF protocol, when planning the network, the IP of civil aviation relay network can be regarded as a preliminary network segment. When realizing the interconnection transmission between ATM network and KU satellite network, each network segment is occupied by a relay system. Although IP interconnection has obvious advantages, it still has disadvantages, such as jumbled physical lines and network security. In order to realize IP interconnection in the shortest time and improve the network security level, a system environment can be added. Through the improvement and perfection of technology, the data transmission in the newspaper automatic forwarding system can be better realized, the work efficiency can be improved, and the reliability of data transmission can be guaranteed.
3 Using FR communication to realize
The method of DMHS system is in civil aviation data network. The interface remains in the method of DMHS system realized by FR transmission communication. After updating the relay system, the FR communication interface will be added, and the information of configuration parameters will also be added in the database. Only by establishing an independent FR process can we transmit and process communication data, report and manage working status. The relay system can realize two intelligent synchronization units at the same time. The main working mode of FR transmission communication is active/active, and each intelligent unit can be connected to ATM network and KU satellite network respectively, while the X.25 communication transmission mode is active/standby mode. There are eight PVC*** connecting KU satellite network and ATM network in the system. As long as there is a PVC that can run normally and ensure the smooth development of data transmission, then every message needs a PVC for data transmission, and the security of data information is guaranteed. When the message application layer returns the certificate, the mechanism of packet loss retransmission in the transport layer is obvious. Coupled with civil aviation data encryption technology, the security level of telegraph information is greatly improved, and all PVC connections have their own heartbeat packet, which ensures their security and confidentiality level and is effectively preserved.
4 Based on FR scheme analysis
Through the transformation of automatic relay system in civil aviation wired communication technology, the intelligent level of relay system is continuously improved, and each intelligent synchronization unit interface is increased to four, which are connected to four network systems respectively: one is connected to the existing FRS800 network of civil aviation for X.25 transmission; Two of them are connected with ATM network system and KU satellite network respectively; The last one is used as a backup. The improved automatic forwarding system can not only connect four FR interfaces at the same time, but also ensure the information throughput of each interface is 2 ~ 8m. In addition, FR connection has many advantages, which changes the management system of civil aviation automatic forwarding system and improves the degree of automation. With the help of the second transit of the Administration Bureau, the provincial bureau can easily realize the interconnection of forwarding information and enhance the interconnection of different forwarding systems. Several trunk lines can form a mesh interconnection, while provincial bureaus and air traffic control stations can form a tree interconnection structure, which promotes the forwarding of civil aviation data network resources.
5 conclusion
Automatic transmission system plays an important role in civil aviation system. The normal operation of automatic transmission communication directly affects the flight situation of civil aviation, which should be highly valued by the civil aviation communication department. At the same time, it is necessary to strengthen the research of newspaper automatic forwarding system, optimize newspaper automatic forwarding system, enhance the communication function of civil aviation, improve the efficiency and security level of information transmission, and give full play to the role of newspaper automatic forwarding system.
References:
[1] He Ling. On automatic forwarding system in wired communication of civil aviation [J]. China New Communication, 20 14 (20).
Ying guanghui. Application of Automatic Forwarding System in Civil Aviation Communication [J]. Science and Technology Consulting, 20 12(07).
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