Quantum microwave photonics (QMWP) technology, which harnesses energy-time-entangled biphotons as optical carriers and employs time-correlated single-photon detection for high-speed rf-signal recovery, has demonstrated remarkable potential in achieving nonlocal rf-signal coding and efficient rf-signal recovery from significant dispersion interference. In this paper, we expound on the principle of maximizing the recovered rf signals in QMWP systems. Through theoretical analysis and experimental validation, we establish a precise relationship between the recovered rf signal's magnitude, the input rf signal's frequency, involved dispersions, and the width of the coincidence selection window. This enables us to determine the optimal width for the coincidence selection window and the corresponding magnitude of the maximized rf signal given the dispersion. These findings offer valuable guidance for improving QMWP systems, thus expanding their potential applications.