Improvement of global navigation satellite system signal acquisition using different grade inertial measurement units for high dynamic applications

Most global navigation satellite system (GNSS) receivers cannot work in high dynamic scenarios because of poor navigation satellite acquisition in these environments. Hence, inertial navigation system (INS) is used to aid the GNSS signal acquisition and improve the acquisition capability of the receivers. In INS-aided acquisition, the Doppler estimation accuracy, which has an effect on the acquisition performance, is largely dependent on the quality of the selected inertial measurement unit (IMU). However, the mathematical relation between the IMU errors and the Doppler estimation errors is yet to be determined. This relation is derived and the relation curves are provided. Owing to the insufficiency of the researches on high dynamic applications, such as missiles and aircrafts, a high dynamic scenario is designed and acquisition experiments with different grade IMU assists are performed. The results of these experiments verify that the INS aid can reduce local frequency search space and achieve fast acquisition. Moreover, the experiments also compare the acquisition capabilities of the receivers aided by different grade IMUs and verify the effect of the IMU quality on acquisition performances. Finally, according to these experimental results, a suitable IMU can be determined for the INS-aided acquisition.