Spaceborne Microwave Detector Software Design And Implementation

Microwave sounder is the first microwave radiometer for lunar exploration in the world. It is very important to implement mission. In this paper, the characteristics and advantages of software design method and the gain control method of microwave sounder are introduced in detail based on the spaceborne microwave sounder project.The microwave sounder's software is embedded real-time software. At present, structured methodology is widely adopted and the most mature design method in embedded software. However if structured methodology is adopted, software is difficult to be modified. Because the complex function of the microwave sounder's software will be implemented by MCS51 compiling language, it will induce some problems such as low reliability, difficult to realize, understand and test etc. This paper selected typical functions of the software which are the management of running time sequence and sampling data to introduce the software design idea and realization in detail. The microwave sounder's software takes the advantage from structured methodology and OOD methodology, respectively. In software design, the functions are divided into several small modules with structured methodology. running sequence is managed with OOD methodology. So the software design of time sequence table is put forward and realized. The running process of the software is inquiring time sequence table. The advantages are simple software structure, incompact module function and structure, high running efficiency, easy to modify and test. In addition, combined the requirement of the spaceborne software design, the software is carried out the reliability strategy design and realization. It indeed improves software reliability and quality.Gain control method which combines offset voltage and automatic gain control is designed and realized in microwave sounder firstly. Gain automatic adjustment can make receiver works in linearity. Offset voltage adjustment to get rid of receiver noise. This can realize fast and accurate adjustment.According to requirement of the software engineering, the microwave sounder's software is developed. Every test and experiment result show the software meets mission and high reliability requirement. Validity, effectivity and superiority of the method of time sequence table and the gain control method are fully proved. Moreover, the method of software design will provide reference for developing of other spaceborne software. The method of automatic gain control can provide reference for design of other microwave radiometers.