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Abstract. Temperature is one of the most basic environmental parameters. The measurement and control of temperature are of great significance and application value in people's daily life and industrial production. So, this paper realizes the temperature monitoring system based on STC MCU. The DS18B20 temperature sensor is used in the hardware, and the display circuit, temperature overrun alarm circuit and key input circuit are set up. Finally, according to the design of the system, the temperature measurement accuracy and stability are tested, and the results show that the measurement error of the system can be controlled within 1℃. in addition, the system has the characteristics of simple measurement, low cost and easy to use, good market prospects.

it is known that the free-space optical communication is one of the most promising communications, and the ATP system especially coarse pointing subsystem is the key to construction and maintain of the communication link. To our knowledge, only few experimental experience for coarse pointing subsystem exists today especially with respect to communication construct in cities. Therefore, an experiment system for coarse tracking system simulation for free-space optical communication between buildings is set up. The control strategy adopted in the coarse pointing subsystem is described and some experiment with different simulation speed under constructed system has been done. The result shows that control accuracy is several hundreds of microradian and can meet the system requirement. Standard deviation for tracking error of X-axis increases with the increase of simulation speed, but has no order for Y-axis.

The performance of radio frequency (RF) cable, the main physical carrier of signal transmission, is affected by multiple factors. This paper sets up a 3D finite-element model of the RF cable to study the signal attenuation features of such single factors as insulating layer thickness, signal frequency and ambient temperature. Then, the insertion loss and variance analysis of nine parameters of the RF cable were discussed in orthogonal design. The results show that the signal attenuation is positively correlated with signal frequency and ambient temperature, but negatively correlated with the insulating layer thickness; in terms of the effect on insertion loss, the parameters are ranked as signal frequency>insulating layer thickness>ambient temperature in descending order. Next, the author obtained the signal features and proposed a multivariate regression model. The experimental results show that the model has an error of less than 3%, an evidence of high accuracy.