Di Wu

The mega-launch of low Earth orbit satellites (LEOs) represents a critical opportunity to integrate navigation and communication (NavCom), but first, challenges related to signal design must be overcome. This article proposes a novel signal scheme named CE-OFDM-PM. Via research on the in-band or adjacent band, it was found that the proposed signal scheme was suitable for S-band and had a wide normalized power spectrum density (PSD), high peak-to-side lobe ratio (PSR), and multiple peaks in autocorrelation. In an analysis of the simulation performance evaluation in navigation and communication, it is found that the proposed signal scheme has the potential for high accuracy, a code tracking accuracy of up to 0.85 m, a small mutual influence between the proposed signal scheme and other schemes, excellent anti-interference properties, and a better performance at both short and long distances in terms of its anti-multipath capability. Furthermore, the proposed signal scheme shows the ability to communicate between satellites and the ground and is outstanding in terms of its bit error rate (BER), CNR, and energy per bit to noise power spectral density ratio (Eb/N0). From the technical, theoretical, and application perspectives, our proposed signal scheme has potential as an alternative scheme in future BDS, PNTs, and even 5G/B5G.

The integrity and accuracy of positioning are crucial factors in vehicle safety. This article proposes an enhanced real-time array calibration (ERAC) technique based on real-time array error calibration with the Beidou Navigation Satellite System (BDS). Through fixed-point positioning tests and road tests, it is found that the ERAC method is superior to the traditional methods in terms of accuracy, stability, confidence, and the time required to reconstruct reliable points. The performance of the tested receiver is better than that of a commercial receiver with standard single-point positioning (SSP) in the context of multipath interference. Furthermore, the ERAC method meets the requirements for autonomous vehicle (AV) monitoring and public safety, especially in terms of the lane-level accuracy indicator, and its integrity indicators are greater than 95% to 97%. Additionally, the ERAC method has the potential to become an alternative solution for automatic vehicle safety monitoring in certain scenarios. This technique also has the ability to meet the wide positioning requirements of various vehicles and scenarios by adjusting its technical details.