In this paper, a detailed study based on RFID technology will be described about the basis of the indoor location, and the further study of the Pseudo-range principle of absolute positioning after received data.

Based on introducing trigonometry locating algorithm and pseudo distance locating algorithm,a locating idea was puts forward,which combines the two locating algorithms to improve the precision of locating.

Research on the Algorithms of Absolute Positioning and Its DSP Implementation;

Aiming at weakness of the existing ultrasonic absolute positioning method and the ultrasonic propagation characteristic,the fusion method for redundancy ultrasonic information(FMRUI) is proposed.

Application of the absolute positioning system based on pulse width coder in the maglev train is presented.

This paper put forward the software design method for valuate the satellite pseudo-range positioning accuracy, that the software has a function to evaluate the affection that various arithmetic to the positioning accuracies, still having the function to select.