Abstract：In order to solve the problem of frequent blocking of signals caused by dense debris and urban canyons, and complex strong electronic interference caused by high-voltage power communication facilities or earthquakes during the occurrence of serious and super-large disasters, the receiver clock bias was predicted in a short term based on the time series theory, and the clock bias prediction value was used to assist the timedifferenced carrier phase (TDCP) algorithm to realize the function of obtaining three-dimensional velocity measurement information for downloads in severe environments. Because the TDCP avoided the problem of ambiguity resolution for the whole cycle, it could effectively weaken the common mode errors with obvious time series, and had a characteristic of high accuracy in a short term, so that less than four GPS active satellite constellations were used to obtain short-term prediction values of receiver clock bias with certain accuracy through ARIMA model to expand the observation conditions of velocity measurement, and short-term high-accuracy velocity measurement results with TDCP. The measured data showed that this scheme could meet the requirements of carrier speed measurement without adding additional hardware in the time scale of 80 s and under the condition that the number of effective satellites was insufficient. The speed measurement accuracy can reach the decimeter level under dynamic conditions.

Keyword：ARIMA model;clock bias prediction;TDCP;velocity measurement;