Ding Wenrui

Software dependability evaluation based on quality characteristics

In the reference of ISO/IEC 9126 software quality model, this article establishes a comprehensive evaluation system of the software dependability. At the same time, it uses the concept of entropy to combine subjective weights and the entropy of objective weights to determine the weight values of measurements in the evaluation system. On this basis, take advantage of the trapezoidal-semi-trapezoidal which is used to depict the degree of membership in the fuzzy mathematics to divide software dependability and put forward a detailed dependability evaluation process and method based on fuzzy mathematics evaluation. Preliminary experimental results show that software dependability evaluation system based on fuzzy mathematics theory is convenient and practical. The factor weights determined by an objective entropy values and the experts subjective weights combine the subjective and objective factors. The results of evaluation is objective, rational and more effective to reflect the current level of dependability. It lays the groundwork to the study of software dependability evaluation.

Multi-parametric Programming Approach for Data Link of UAS Based on State Machine

With the huge development of Unmanned Aerial Vehicle (UAV) in both military and civilian applications, the Unmanned Aircraft Systems (UAS) are required to adapt to complex environment and various missions. The adaptation technologies for UAS include adaptive modulation method, adaptive coding method, adaptive antenna diversity or power and adaptive parametric of data link. In this paper, we proposed a multi-parametric programming approach for data link of communication system in UAV based on state machine. We also present the state transition design for the state machine and describe the transition in detail according to different parameters of data link. In addition, the implementation of the state machine is presented.

Typical channel coding and modulation scheme for satellite communication systems

This paper analyzes the characteristics of the satellite communication system as well as the satellite communication channel and introduces the basic principles and outstanding advantages of convolutional code and MSK modulation. The combined implementation of properly chosen convolutional code and MSK modulation is a feasible scheme for the satellite communication with existing power limitation and all kinds of potential fading and noise. BER performance of convolutional code and MSK is simulated with Matlab/Simulink. The conclusions based on the simulationpsilas results provide references to the design of the satellite communication system.

Adaptive Equalizer Design for Unmanned Aircraft Vehicle Image Transmission over Relay Channels

A novel length adaptive method is proposed for time domain equalizer by taking the channel attenuation ratio between different multipath components into account in UAV-UAV and UAV-ground channels. Then, considering received image quality, the minimum bit error ratio (MBER) criterion is exploited to design adaptive equalizers for both amplify-and-forward (AF) and decode-and-forward (DF) relaying systems by the proposed length adaptive method. Results show that proposed MBER adaptive equalizers outperform the traditional ones in bothAF relaying andDF relaying as channel attenuation ratio inUAV-ground channel increases. Moreover, DF outperforms AF as channel attenuation ratio in UAV-UAV channel increases. Furthermore, bit error ratio (BER) and peak signal-to-noise ratio (PSNR) performances in both AF and DF are evaluated to show the enhancement by the proposed MBER adaptive equalizers.A novel length adaptive method is proposed for time domain equalizer by taking the channel attenuation ratio between different multipath components into account in UAV-UAV and UAV-ground channels. Then, considering received image quality, the minimum bit error ratio (MBER) criterion is exploited to design adaptive equalizers for both amplify-and-forward (AF) and decode-and-forward (DF) relaying systems by the proposed length adaptive method. Results show that proposed MBER adaptive equalizers outperform the traditional ones in both AF relaying and DF relaying as channel attenuation ratio in UAV-ground channel increases. Moreover, DF outperforms AF as channel attenuation ratio in UAV-UAV channel increases. Furthermore, bit error ratio (BER) and peak signal-to-noise ratio (PSNR) performances in both AF and DF are evaluated to show the enhancement by the proposed MBER adaptive equalizers.

Target tracking based on multi-color joint probability statistics model

For real-time target tracking under complex scene, a target tracking algorithm based on multi-color joint probability analysis model was presented. The algorithm adopted color histogram to represent the target statistical characteristic with Camshift principle, and carried out exploratory research in such aspects as multichannel joint color features statistics, projection map area weighted processing, the tracking window size and position calculating, algorithm processing mechanism of circulation. It used red (R), green (G), blue (B), hue(H), luminance (Y) channel color as the target observed characteristics, and designed the calculation method based on the probability statistic to distinguish any color target from complex scene. It also established the calculation method for tracking window size and position which adapted the multi-color model. Using weighting projection map area method, the background interference around the target potential area was eliminated. At last, more reasonable convergence judgment and the algorithm cycle rules were put forward. After the experimental certification, the real-time performance and detection ratio present a good result.