Abstract:  Taking advantage of the characteristics that the deployment STACER can be used as an antenna，two sets of STACER were used to form a detection baseline，which solved the contradiction between the length requirement and the limited folding envelope in the TianWen-1 mission.Compared with other subsurface radar antenna deployment mechanisms，it was pointed out that the STACER had the smallest storage volume and the largest stow ratio，and was most suitable for applications where multiple sets of loads need to be installed.The composition and working principle of the STACER were described.The relationship between the mechanical performance and the configuration parameters was given.The calculation formulas of the driving force and the fundamental frequency of the STACER were obtained.The formulas show that the fundamental frequency is determined by the strip width，thickness，the root radius and tip radius.The driving force is in proportion to the elastic modulus，strip width，and the cubic of the strip thickness.The strip thickness has the greatest influence on the driving force.The fundamental frequency and driving force of the STACER are tested，and the test results are consistent with the analysis results.

Key words: subsurface sounding radar, STACER, first frequency, deployment force, configuration parameters