Imaging based on signals reflected from global navigation satellite systems (GNSS) represents a novel approach for surface observation. Owing to the global coverage of navigation satellite constellations and the short revisit periods of satellite sub-points, GNSS reflectometry imaging enables high-temporal-resolution change detection in sensitive areas. However, stationary dominant reflectors (SDRs) in the imaging area suppress the signal amplitudes of nearby weak reflection targets, thereby increasing the difficulty of their detection. Conventional coherent change detection and differential interferometry methods demand high phase accuracy and require multiple imaging operations within the imaging domain, thereby reducing detection efficiency. To address these issues, this study proposes a method for directly suppressing SDRs directly in the range-compressed domain. This method leverages the extensive cancellation algorithm batches (ECA-B) framework and utilizes a single satellite revisit period to construct a scattering characteristic model dominated by SDRs, which serves as the reference signal for ECA-B cancellation. To ensure model stability, two-dimensional range-compressed results from multiple prior revisit periods were accumulated to construct a weighted scattering characteristic model, incorporating noise mean and variance. Simulations and real-world experiments demonstrated that the proposed method significantly attenuates signals from strong reflectors in the range-compressed domain, thereby enhancing the detectability of weak change targets.

An experimental analysis method for the correlation peak distortion of the BeiDou‐3 satellite navigation system (BDS‐3) B1C signal is proposed to address the gaps in existing research—lack of experimental validation and insufficient insights into tracking loop distortion mechanisms under spoofing. First, the autocorrelation characteristics of the B1C signal under narrow band (NB) and wide band (WB) tracking modes were analysed based on its modulation characteristics. A feeder‐based BDS spoofing experimental platform was constructed to accurately simulate real‐world spoofing scenarios and collect high‐fidelity intermediate frequency (IF) data. Multi‐correlator tracking outputs were utilised to quantify the distortion effects of spoofing types and tracking modes on the B1C tracking loop. Experimental results revealed three key findings: (1) during spoofing takeover, the combined correlation peak oscillates at high frequency (spoofing as reference, residual true signal as amplitude); (2) under position spoofing, correlation peak pulling direction/rate vary by satellite; under time spoofing, the pulling is consistent across satellites; (3) WB tracking offers higher ranging accuracy than NB tracking but is more susceptible to spoofing‐induced pulling and exhibits a more complex correlation peak distortion. These results provide a theoretical and experimental basis for the design of BDS‐3 anti‐spoofing algorithms and equipment optimisation.

To address the limitations of traditional navigation systems in lunar exploration missions regarding positioning accuracy and coverage, this study proposes a multi‐objective optimization framework for the Lunar Navigation Satellite System (LNSS) to support the lunar re‐exploration mission. A comprehensive simulation system encompassing the entire mission process—powered descent, landing, and surface operations—was developed, integrating a hybrid‐orbital architecture (DRO, ELFO, and NRHO) and a multidimensional navigation performance evaluation model. An improved genetic algorithm (IGA) was employed to optimize the constellation configuration under constraints including satellite count ( N = 9), geometric dilution of precision, signal attenuation, and cost (75% reduction compared to full‐scale architectures), yielding the optimal D1E4N4 configuration. Experimental results demonstrate that the optimized LNSS achieves continuous four‐satellite visibility during critical mission phases (landing preparation, powered descent, and surface exploration). The system effectively mitigates signal occlusion caused by complex lunar terrain. These findings provide critical technical support for China’s crewed lunar missions and the International Lunar Research Station (ILRS), advancing the transition of Earth–Moon navigation systems from theoretical validation to practical implementation and laying a foundation for sustainable deep‐space exploration.