1553B bus in arms comm application (1)

Summary: due to the characteristics of good 1553b bus, in the modern weapon systems, 1553B bus is playing an increasingly important role.

This article describes the characteristics of the 1553B bus and message transport mechanism, and the weapons communication situation.

Keywords: 1553B bus; weapons; message transmission; communications; application

1 Introduction

With the development of technology and the needs of the war, combat vehicles, ships, aircraft and other weapons platform electronic devices more and more and more complex, electronic equipment according to certain agreements are effectively integrated networking, the sharing of resources and capabilities have become inevitable.

Electronic integrated supporting technology is networking, and weapons platform networking technology is different from ordinary local-area network technology, it places particular emphasis on network reliability and real-time. 1553B bus was originally in the late 1970s to accommodate aircraft development from the United States proposed airplanes internal electronic system networking standard, due to its high reliability and flexibility in other mobile weapons platform has been more widely used.

　　

2 introduction to 1553b bus

1553B bus is the short name, its mil-std-1553b the aircraft in response to the internal time-directive-multiplex data bus.

Because of its transmission rate is high, the device connection simple and flexible, noise and high efficiency high, communication and reliable, as the US military standard as airborne equipment to communicate with the bus standards. From launch to now, after thirty years of development, 1553B bus technology is constantly improving. Currently 1553B bus has become in the aerospace field dominance of bus standards.

1553B bus is a centralized time serial bus, whose main characteristic is the distributed processing, centralized control and real-time response.

Its mechanism includes a mistake-proof reliability, fault tolerance and error detection and location of the error, the isolation, error correction, system monitoring and system recovery capabilities. Dual-redundant system, there are two transmission channels, have guaranteed the good fault tolerance and fault isolation. Together 1553B bus has the following characteristics: excellent

(1) real-time performance good, the transmission code 1553b bus speed of 1mbps, each message can contain up to 32 characters, transfer a fixed time for short messages.

Data transfer rate than the average high of communication networks.

(2) a reasonable error control measures and specific manner, in order to ensure the integrity of the data transmission, 1553b adopts reasonable error control measures – feedback retransmission error correction method.

When the bus controller bc to a Terminal rt issue a command, or sending a message, the Terminal should be in the given response time sends back a status word, if the transmitted message is wrong, the terminal will refuse to send back status word, this report last message transmission is not valid. But as command not only makes the system can complete the data communication control tasks that you can investigate the failure and complete fault management features.

(3) bus efficiency high, bus forms of topology on bus efficiency requirements is relatively high, as this 1553b bus efficiency indicators involved in certain mandatory requirements such as response time, message interval time and every time that the message transmission of maximum and minimum length of the data blocks are strictly limited.

(4) with the command/response and "broadcast" means of communication, bc to "broadcast" means all rt sends a time synchronization message, so that all messages on the bus transfer from the bus controller issued instructions to control the relevant Terminal on the instruction should be given to respond and perform actions.

This approach is ideal for centralized control of distributed processing system.

3 1553B bus message transport mechanism

1553B bus information is based on the message (message) modulation into Manchester code for transfer.

Each message's longest composition by º32 Word, all words are divided into three categories: command words, data, Word and status word. Each word in a word length of 20 bits, effective information is 16-bit, each word in the first 3 digits of the vocabulary of synchronization-prefix, and the last one is the parity bit. Effective information (16 bit) and parity bit on the bus to Manchester code in the form of a transfer, transmission time of 1 s (that is, bit rate for 1mhz). Synchronization-prefix 3 bit, first as a command after negative words and status word, after being first negative as a data word.

The three types of words, the command word at the start of each message, which provides for the transmission of specific requirements.

　　

Status word can only be issued by the rt, it's content on behalf of the rt on bc issued effective command of feedback.

Bc can be based on the contents of the status word to determine the next step to take and what kind of operation.

Data characters are administered by bc transit to a rt, rt from a to bc, or from a rt-transfer to another rt, it represents the transmission of data.

Command words, the data characters, as well as the definition of the status word you see in Figure 1

　　

　　

　　

1553B bus on the message transmission process is: bus controller to a Terminal publishing a receive/send instructions, Terminal in the given response time range sends back a status word and perform message receive/send it.

Bc through the acceptance of the status word rt answers to verify the transfer was successful and do follow-up actions.

Message composition 1553B bus communication is the basic unit, if you need to complete certain functions, will be more news organizations into a new structure called a frame (frame).

Frame structure is shown in Figure 2. In the figure, the amount of time a message is called the message time, two messages between called message interval,Complete a time frame is called a frame. In practice these three time can be set programmatically.

　　

　　

　　

4 1553B bus in weapon communication

As mentioned earlier, now weapons of electronic equipment continues to increase, how will these electronic devices to be effective integrated, thus the resources and capabilities of the integrated has become an inevitable requirement for weapons development.

Weapons, integrated electronic system Foundation is using data bus structure, use the data bus that processor (including hardware and software), the information transmission and control displays three subsystems for various tasks. This has the following advantages: reduction of arms device size and weight, reducing crew workload, improve weapon system reliability, reduce costs, improve the detection accuracy, and enhance the autonomy of the system, and so on. Modern weapons systems communication requirements generally include the following:

A, can effectively achieve the transfer of data between the subsystem and meet specific communication characteristics;

B, so that communication relative to work independently, as transparent to the application software, and a host of time cost as little as possible;

C, enables communication system flexible, easy to modify.

D, with strong anti-interference ability.

And the excellent performance, 1553b bus just to satisfy the above points, making it in modern weapons systems has received increasing attention, has become a combat vehicles, ships, aircraft and other weapons platform electronic system's main pillars.

Avionics systems usually include a dozen airborne computer subsystems, how to effectively achieve the subsystem data communication between the success or failure of the entire air transport system will undoubtedly play a key role.

In 1973, the United States announced a military standard mil-std-1553b bus, it quickly was applied to the air force, f-16, f-18, b-1 and av-sb and many other aircraft. Figure 3 is 1553B bus in fighters in communication application model diagram:

　　

　　

　　

The world can be used as a military standard and specialized ship-to-use tactical data bus: there is a lot of, but use most of the United States or when pushing mil-std-1553b.

1553b transmission medium there is coaxial cable, optical cable, shielded twisted pair, and so on, through transformer coupled or direct coupled way Terminal coupled to the bus. The data bus transfer rate, transmission distance, remote terminal, can better meet all kinds of small and medium-sized warships and submarines system communication requirements, the application is very popular.

　　

Military vehicles and combat vehicles as ground weapons combat platforms, often working in strong vibration, noise, dust, temperature changes in the harsh environment.

Therefore, its internal electronic data communication between devices through strict fault detection, to achieve high reliability, the remnant and fault tolerance. In the real-time, dynamic system integration control to the engine and transmission control, the data communication requires a message of maximum response time is generally not exceed, the engine and transmission of real-time control, thereby enhancing the overall performance of dynamical systems. In addition, there are some of the data communication protocol for special requirements such as simplicity, short frame information transfer and information exchange of frequent sexual, network load, stability, high security and price/performance ratio, etc. 1553B bus with high reliability and excellent real-time, integrated Powertrain control such many kinds of data communications, data volume, real-time demands high, network node less system, 1553B bus than the existing majority bus has better performance advantages

1553B bus in arms comm application of key technology generally include the following:

1) bus interface hardware and software design.

Using interface card or interface controller forms with weapons and various subsystems of hardware connections. At the same time, the need to write the appropriate traffic control software, including the transport layer software and driver layer software through the sharing of information and resources, in accordance with the weapons of war, on the application tier comprehensive real function.

　　

2）接口控 [1] [2]