Differential wavefront sensing (DWS) is widely adopted for high-precision angular detection in interferometric systems, yet its measurement range is constrained by the nonlinear implicit phase–angle relationship. This paper proposes a strategy-enhanced differential evolution algorithm, termed Bi-inheritance and Tournament-Selection-based Differential Evolution (BiTsDE), to suppress nonlinear angular errors. The method introduces fitness-guided inheritance of mutation and crossover factors and tournament-based elite parent selection, enabling adaptive balance between global exploration and local exploitation. Unlike conventional DE variants that mainly tune control parameters, BiTsDE optimizes the evolutionary search strategy, enhancing early-stage diversity and late-stage convergence stability. Simulations demonstrate angular resolution better than 0.06 nrad within ±1 mrad. Experiments show that up to 600 μrad, BiTsDE reduces demodulation error by 99.9% compared with linear DWS, achieving 17.9 nrad precision and 42% faster convergence. These results validate BiTsDE as an effective solution for nonlinear error suppression in DWS-based high-precision optical metrology, particularly for space-based gravitational wave detection.

In space-based gravitational-wave detection, the noise budget assigned to the point-ahead angle mechanism (PAAM) is at the picometer level within the 0.1 mHz–1 Hz. However, environmental disturbances severely restrict the effective bandwidth of PAAM-dependent parasitic displacement in differential wavefront sensing (DWS), rendering conventional approaches inadequate for low-frequency observability. This paper proposes a model-based evaluation method via frequency-domain extrapolation. The low-signal-to-noise-ratio optical path difference (OPD) in the environmental-additive-noise-dominated small-deflection regime is inferred by exploiting the transfer function and the Fourier transform. Experiments confirm strong agreement between predicted and measured displacement spectra. The method achieves parasitic displacement sensitivity better than 1pm/√Hz×NSF( f ) across the band without sole reliance on extreme thermal control. This approach provides a practical strategy for improving low-frequency precision interferometric metrology in space-based gravitational-wave detection and related applications.