There are some differences in dielectric constant and temperature of frozen soil and unfrozen soil physical parameters

and differences is obvious in value. Based on this feature

propose a method for frozen soil detection which takes use of the theory of physical properties difference of air

soil

water and ice

based on this

design a capacitive sensor which realize fusion measurement of multiple parameters on frozen soil

soil moisture

soil temperature and frozen soil depth. Through comparison and analysis

the result shows that correlation coefficient reaches 0. 99

average absolute error is less than 2. 5 cm

which meet the requirements of frozen soil auto measurement technology

and it can be applied to frozen soil observation station

instead of manual observation.