Оценка долговечности СВЧ-транзисторов
Assessment of the durability of microwave transistors
The question of ensuring reliability, especially of durability of mobile communication systems on the stage of planning, is considered in this paper. The purpose of this work is rising quality of projection radio engineering devices (their components) of mobile communication systems. Research of real methods for calculating the indicators of longevity radio engineering devices was conducted for aim achievement. They have some disadvantages, because according to industry standards 4.012.013-84 they use constant value of variation coefficient in mathematical expression. Unified method in the form of IDEF0-diagram was proposed for elimination of defects. It allows to remove quantification of the durability of the constituent parts of the mobile communication systems of «resource» type. Method consists of five successive steps: the formation of source data, updated calculation of variation coefficient, calculation of storage time, evaluation of complex load factor and calculating of indicators of «resource» type. Notably attention is paid to calculating of updated variation coefficient, which makes a significant contribution to the result. It was detected that it is necessary to apply complex load factor in mathematical expressions in the evaluation of resource of radio engineering devices of mobile communicational systems, because it considers both electrical load and temperature, which is explained by the thermally dependent electrical parameters of electrical components. A summary table of the mean group value of the coefficient of variation for certain subgroups of electrical components was compiled. This table is accessory to counting indicators of durability of «resource» type if the necessary electronics are not available in handbooks about reliability. The calculation of the quantitative values of the durability of the video transmitter with the construction of visual dependencies of gamma-percent resource on the complex load factor was completed. Dependences that have been obtained mirror underestimation of gamma-percent resource with the method which is given in industry standards 4.012.013-84 compared with the proposed. It is recommended to integrate the results of research into methodology of calculating of reliability indicators of «resource» type of components at enterprises and research institutes engaged in the development of mobile communication systems.
The paper considers the use of alpha-distribution to analyze the influence of radiation on the reliability of command and measuring systems of the spacecraft. The financial support from the Government of the Russian Federation within the framework of the implementation of the 5-100 Programme Roadmap of the National Research University – Higher School of Economics is acknowledged.
This study (researchgrant No 15-05-0029) was supported by The National Research University–Higher School of Economics’
Academic FundProgramin 2015/2016.
Constant growth of spacecraft operating life requirements leads to creating equipment which fits these requirements. From this point of view, specifically durability prediction allows to evaluate the potential of creating equipment with a long operating life. On early stages of equipment’s development analytical methods of durability prediction are used. Obviously, the more precise the estimation is, the more likely that the practical test will confirm the durability predictions. Therefore, improving the engineering techniques of the durability prediction is a relevant problem.
The objective of this research is to improve the quality of design work by enhancing the engineering techniques of the durability prediction, which raise the authenticity of the evaluations.
Life of the equipment are calculated using the statistical modelling method (Monte-Carlo method). This method takes into consideration probabilistic characteristics of constituent elements’ life.
As a result, the problem of predicting operating life of electronic equipment using the reference data on early stages of development is solved. An analysis of standardized method of durability prediction was performed which revealed existing limitations for using this method when predicting operating life of electronic equipment. An alternate, statistical method of predicting operating life of electronic equipment was suggested and a software implementation was created. Developed software was tested and verified. Analytical experiments were performed to show the authenticity of the suggested method and to compare it to the standardized one.
Thus, results of the performed research show that the standardized method is applicable only for calculating the minimum operating time. Also, it was concluded that the truncation parameter of element’s life distribution, variation coefficient of life and some specific qualities of dependability prediction scheme have to be taken into consideration when predicting durability of electronic equipment.
The paper offers methodology for estimation of durability indices of the modern integrated circuit communication network, which has reports about the conducted tests on non-failure operations and conservability, but has no data for the durability. The paper describes two approaches, which apply for generation of basic data and which allow to receive reliable result, typical for the certain operating conditions.
The article deals with forecasting the dependability indicators of state-of-the-art spacecraft onboard equipment. The authors demonstrate the applicability of the results of equipment and components testing for resistance to ionizing radiation in forecasting dependability indicators. They prove the applicability of Alfa distribution of time to failure in forecasting CMOS IC reliability and longevity. The paper presents design ratios for probability evaluation of fail-safe operation, mean time to failure and minimum operation time. Ways are shown to improve the resistance of state-of-the-art spacecraft onboard equipment through the use of specialized means of protection against the effects of ionizing radiation of the outer space. This research (No. 14-05-0038) was conducted with the support of the Higher School of Economics Academic Fund Program in 2014.
The report considers the issues of forecasting the reliability parameters of modern on-board equipment of spacecrafts. The expediency of using the results of tests of equipment and it’s components for resistance to the effects of ionizing radiation to predict the reliability parameters. Substantiated the possibility of alpha-time distribution for the MTBF prediction of reliability and durability of the CMOS integrated circuit. Shown the calculated ratios for estimating the probability of failure-free operation, the mean time between failure and minimum service life. Given possible ways of increasing the life of modern on-board equipment of spacecrafts by using specialized methods of protection against ionizing radiation of space. This study (research grant No 14-05-0038) was supported by The National Research University - Higher School of Economics’ Academic Fund Program in 2014.