In wireless sensor networks, sensing tags are battery powered, which also limits the battery life. Therefore, it is particularly important to study self powered sensing tags. At present, passive wireless identification systems can achieve self powered communication through tags.However, wireless power supply sensing systems have problems such as low efficiency and short communication distance. To reduce the power consumption of sensing tags and improve the efficiency of sensing systems, a passive wireless low-power hydrogen concentration sensing system is designed. To further reduce the power consumption of sensing tags, a passive wireless magnetic field intensity sensing system is developed.In addition, to solve the low efficiency of multiple sensing labels in wireless power supply sensing systems, an efficient anticollision algorithm based on dynamic binary query trees is designed. According to the research results, in the cold start indoor environment, the energy collection rate of the sensing tag designed in the research was 0.081mJ/s, and the energy collection efficiency was 25.7%.In single/dual sensor mode, the maximum values of sensing error were 2.1% and 5.2%, respectively. The maximum recognition time of the anticollision algorithm based on dynamic multi base query tree was 2.78s, and the minimum value was 1.31s.The research results can provide methodological and technical support for the improvement of wireless power supply sensing systems, expanding the application range of wireless power supply sensing systems.