For the problem of no reset federated filter overall sub optimal fusion accuracy and the adjustment of unequal interval filter for multi source information,an unequal interval federated filter algorithm based on sub filter modified covariance correction for multi source information is proposed.In the case of barely raising computer load,the filter’s fusion accuracy is improved by modifying sub filter’s covariance.Meanwhile, the INS/CNS/SAR/TER integrated unequal interval filter implementation scheme for high altitude long endurance(HALE) UAV is designed.The state updating method of the master and sub filter is proposed,thus the adaptation problem of unequal interval federated filter algorithm for multi source information is solved at the same time can keep the good performance of fault tolerance with no reset mode.The simulation results show that these algorithms have an obvious improvement of fusion accuracy compared with the traditional scheme.