In order to improve the robustness and accuracy Of indoor positioning system, in this paper, the several kinds of common now known the localization algorithm of the ReceivedSignal Strength Indicator (RSSI), Time Of Arrival (TOA), Arrival Of Difference Time (TDOA), Angle Of Arrival (AOA) carried on the thorough research, through various validation on theory and simulation, finally sure to locate the TDOA algorithm with better effect research foundation for the following research.Although Geometric Dilution Of Precision(GDOP )is often used in the field of satellite positioning, it conforms to the application basis of indoor positioning in theory, and the feasibility of extending it to indoor environment is verified by simulation.Then combining the advantages and disadvantages of various positioning algorithms, a GDOP weighted indoor positioning algorithm based on TDOA improvement is proposed.In this thesis involves the indoor localization algorithm, this paper first in advance based on the measured data from the wavelet analysis has nothing to do to eliminate or reduce transmission signal in noise interference, then through the processed data by TDOA algorithm can improve the initial data are required for the position of anchor point, finally further optimized positioning accuracy by kalman filtering algorithm and its robustness.Then, the effectiveness of the hybrid positioning algorithm is verified by MATLAB simulation platform.