关键词: 多址干扰, 测距精度, 反馈校正, 串行干扰抵消, 地基伪卫星, 导航

Abstract: The terrestrial pseudolites system is easy to realize high accuracy positioning comparing with the low transmit error in lineofsight propagation link, while it has approximate constant ranging error under its multiaccess interferenc(MAI) for all terrestrial pseudolites having constant positions. A correction method based on feedbackSIC (Serial Interference Cancellation)was given. First the receiver decide whether it is in strong nearfar effect area based on ranging and coarse positioning data; then restrain the interference of strong pseudolites′ signals on needed signals′ ranging by SIC; a feedback structure was adopted to enhance the cancellation performance. The simulation and hardware test results show that the method has an effective ranging correction performance which could reduce the error from tens of meters to 0.3 m in certain environment with high near-far effect.

Key words: Multi-accessinterference, Rangingaccuracy, Feedbackcorrelation, Serialinterferencecancellation, Terrestrialpseudolites, Navigation