In GNSS/INS integrated navigation, Due to the deep processing to the baseband level of GNSS, the hardware integration is difficult, so most of them are still in the stage of simulation and principle verification. In this paper, for the deep combination technology, at the baseband processing level, for the problem of different output frequency of GNSS system, INS system and loop, the data re-engineering method is designed for data alignment. For the data transmission delay problem of the GNSS system and the INS system, the time synchronization of the GNSS system, the INS system and the loop part is performed by means of hardware timing;For the INS solution and combined filtering takes a long time, affecting the real-time output of the INS data, the dual INS core is designed to ensure the real-time and accuracy of the INS result. The experimental results show that the INS-assisted GNSS loop can complete the loop tracking task, and the smaller loop bandwidth can be obtained when using the auxiliary information. The designed loop-assisted algorithm can realize the deep combination method and lay a good foundation for the next step in high dynamic application.