Aiming at need of high precision ranging

a high precision ranging system of time difference of arrival（TDOA）

which is controlled by field programmable gate array（FPGA）

use TDC-GP1 high precision time digital transfer chip and 433 MHz super regeneration RF transmitting and receiving module

is designed.The system is composed of transmitting node and receiving node.In the transmitting node

433 MHz super regeneration RF signal and ultrasonic wave signal are transmitted synchronously by FPGA.In the receiving node

time arrival difference of received RF signal and ultrasonic signal is measured by TDC-GP1

measurement parameter configuration

measurement results read out of TDC-GP1 and serial data upload to host computer are finished by FPGA.In the system

measurement process is coordinated by Zig Bee wireless communication modules and receiving module and temperature is measured for compensating ultrasonic wave propagation speed.Experimental results show that the ranging system has broad prospect in application with advantages of high precision and reliability

and can be applied easily for wireless positioning system.