The Implementing and Researching of BIT in Airborne Computer - Advanced Research on Computer Education, Simulation and Modeling - page 192

The Implementing and Researching of BIT
in Airborne Computer

Xinyu Tian 1,2 , Xiaolin Zhang 2 , Haitao Wu 1 , and Ying Yao 1,3

1 National Time Service Center, Chinese Academy of Sciences Lintong,
Shaanxi, 710600, China
2 No 365 Institute Northwestern Polytechnical University, Xi'an 710065, China
3 Department of Electronic and Information Engineering, Xi'an
University of Post and Telecommunications, Xi'an 710121, China

Abstract. BIT (Built - in Test) is an important ways to improve the performance
of testing and maintenance in the airborn computer. But the widespread use of
BIT is hindered by the high false alarm rate. A new BIT design strategy and
arithmetic for airborn computer is proposed in this paper to reduce the false alarm
rate. And some BIT solutions of key technologies in airborn computer are given
in this paper, such as digital I/O channels, A/D channels, D/A channels and serial
interface. It is proved by practice that the BIT design strategy proposed in this
paper can improve the test cover rate to 90%, reduce the false alarm rate to 35%,
make the reliability and maintainability of the airborn computer increasing
obviously.

Keywords: BIT, Airborne, Reliability, Maintainability.

1 Introduction

BIT(Built In Test) is a new technology for system testing or fault diagnose and
isolation, it become more and more important in the reliability and maintainability
design of the aviation electronic equipment. The more complex the airborn computer is,
the more important the system's BIT technology is [2]. The BIT technology effect the
healthy rate of combat equipment, the task executing and the system or device's
function and state report giving directly. So BIT technology can shorten the
maintenance time, debase the maintenance fare [3].
It can achieve the high cover rate and low false alarm rate in BIT testing and improve
the reliability and security of airborn computer by designing special circuit and soft
ware in airborn computer.

2 The Design and Realization of System BIT

The excellent BIT system can test each part function of the system, diagnose and
isolation the system's fault correctly, improve the reliability, viability and MTBF
(mean time between failure, MTBF) of the system. The fault testing rate, the fault