Aiming at the problem of poor visibility of single system satellite signal due to the shielding of surrounding buildings in complex urban environment or indoor environment, a joint positioning system was designed to locate single point, and Kalman filter algorithm and federal Kalman filter algorithm were used to process the positioning results respectively. In order to verify this conclusion, we used the GPS/BDS dual-mode positioning receiving module in MC20 to collect positioning data, and the data collected by Jisubo UG905 was used as the reference data of the anchor point. The results show that compared with the reference data, the error of the federated Kalman filter is reduced by 9.54% in the linear distance and 53.43% in the elevation. The results show that the positioning data processed by federated Kalman filter has good reliability and high precision, which can improve the accuracy and accuracy of positioning more effectively.