Wireless communications in hostile atmospheres: radio propagation model and response of constituent elements of the radio front-end at high temperatures

Abstract

In this work the effect of high temperatures is analyzed on the lowest range of communications obtained when the wireless communication system is in the presence of high temperatures (873 K – 1273 K). A solution to avoid the problem is proposed. The temperature range is 873 -1273 K since the temperatures can be in the proposed range for forest or urban fire. This work takes in to account two attenuation factors: The first is the wave attenuation due to the variation of the constitutive parameters of a low ionized propagation medium as function of temperature. These parameter variations are analyzed theoretically, and the obtained results validated experimentally. Secondly, the electromagnetic behavior of one of the most important elements in the radio front-end system: the antenna is analyzed. Finally, the future work and the conclusions are presented. The experimental work was done at 2.4 GHz and between 900 K- 1300 K. From the experimental results an attenuation in the order of 10-5 dB/m at 923 K is obtained, and a complex relative permittivity equals to 1+j10-12. From the experience with the antenna, an readapted antenna is obtained as the temperature is changed to a higher one: a shift of 78 kHz/K, for a temperature delta of 85 K was obtained.

Keywords

• electromagnetic waves propagation
• high temperatures
• attenuation
• phase constant
• constitutive parameters
• circuits at high temperatures