An assisted-GPS positioning algorithm was proposed.Based on this algorithm

the receiver needn’t accomplish the bit synchronization

frame synchronization and navigation data demodulation

which were usually necessary for the conventional GPS receiver

it could implement the positioning solution only by the measurement of pseudo-code phase and the assistance data（including ephemeris information and satellite clock corrections etc.）.Compared with the conventional GPS positioning algorithm

the proposed algorithm increases the ambiguity of the signal transmission time as an unknown parameter for the pseudorange equation.When the initial errors of approximate location and receiver’s clock bias were subjected to a constraint domain

the ambiguity of the signal transmission time could be eliminated.Then

the iteratively equation for this algorithm was derived

and the main steps were summarized.The simulation results show the validity of the algorithm.