Abstract: The applications of Embedded wireless sensor is very broad.This paper describes ultrasonic sensor-based targeting system principle, analysis of the interference present in the system and improved anti-jamming algorithm.We use S3C2440A micro-processor.This system composed by ultrasonic receiver and transmitter module, temperature measurement module and LCD module.We use Linux operating system as software platform.the main design of the system control program and the position calculation process, the system Achieved in indoor as well as some of the special and high precision positioning in harsh environments.The system has good computing ability and has good scalability and adaptability.