Abstract: For problems of large cost and high requirements for hardware of international standards such as GPRS, ZigBee, WiFi, etc., the paper proposed a design scheme of wireless sensor network based on SimpliciTI protocol which has low power consumption and is suitable for small scale RF network. Firstly, it introduced basic principle of SimpliciTI protocol. Nextly it gave a circuit design scheme of wireless sensor node by use of CC2500 RF transceiver and MSP430 microcomputer with super-low power consumption, and introduced networking and communication processes of wireless sensor network based on SimpliciTI. Finally, it introduced location algorithm of wireless sensor network based on distance. For big error of normal multilateral location algorithm, it proposed an improved location algorithm, namely calculating revised value of error of node ordinate through minimizing the square value of difference between actual distance and evaluated distance, and revising initial ordinate of unknown node by use of 2D hyperbola algorithm, so as to improve locating precision.