Large-scale low earth orbit (LEO) constellations can enhance traditional global navigation satellite systems (GNSS) in many ways, but the rapid increase in the number of LEO satellites also poses challenges to the anti-interference performance of navigation signals. To improve the performance of the B1C signal in the future BeiDou global navigation satellite system, this paper proposes a modulation method: it enhances the existing quadrature multiplexed binary offset carrier (QMBOC) by using periodic binary hyperbolic frequency modulation (HFM) signals as subcarriers. The enhanced QMBOC signal (QMBOC-HFM) demonstrates superior anti-interference ，multipath mitigation performance and code tracking performance compared to the original QMBOC signal. The proposed QMBOC-HFM provides a potential signal design for future LEO navigation-augmented global satellite navigation systems.