Robust quantum telescope with a greatly extended measurement range: a Chinese remainder theorem-based method

Phase estimation is a central task in quantum precision measurement. However, the intrinsic 2π periodicity of phase readout introduces a wrap-around ambiguity, which confines the unambiguous measurement range to a single period and leads to a structural trade-off between precision and measurement range in high-sensitivity settings. To address this problem, we propose a robust Chinese remainder theorem-based multi-baseline measurement scheme: we choose a set of pairwise coprime scale factors and recover the wrap-around number from congruence relations among the reduced phases. In the setting of optical-interferometric quantum telescopes, we construct a telescope array based on the Chinese remainder theorem using fractional baselines, which substantially enlarges the unambiguous angular range (effective field of view) while retaining the high precision enabled by long baselines. Numerical simulations show that, under the same constraint on the shortest achievable baseline, our scheme achieves an exponential improvement in detection range over existing methods and attains a better range-precision trade-off with fewer probing resources. This framework supports practical multi-baseline quantum-interferometric observations and can be generalized to other phase-sensitive quantum precision-measurement tasks.