本文介紹一種用于汽車倒車避撞的超聲波無線距離測量系統。系統由下位機與上位機兩部分組成，下位機主要由超聲波發射電路、超聲波接收電路、無線收發模塊及單片
機組成，上位機由單片機、無線收發模塊、顯示電路等組成，下位機與上位機之間通過無線收發模塊傳輸信息。文中分析了超聲波測距電路的設計方法，敘述了采用無線通信技術實現數據遠程傳輸的設計思路。該系統測量距離方便、靈活、穩定。
關鍵詞：無線通信；單片機；超聲波；距離測量；溫度補償
Abstract: A kind of ultrasonic distance measurement system used in the car is designed in
this paper. The system includes the lower microcomputer system and the upper microcomputer system. The lower microcomputer system is mainly composed of ultrasonic transmitting circuit, receiving circuit ，wireless communicating module and microcomputer. The data from the lower microcomputer system is transmitted to the upper microcomputer system by the wireless way. The design principle of ultrasonic distance measurement circuit is analyzed. The design method that the data is transmitted is also introduced. The system is of the characteristics of measurement convenience, fast response and stability.
Key words : wireless communicating；microcomputer； ultrasonic；distance measurement； temperature compensation