By the criterion 1, the range of searching velocity has been confined to $vsn=vs0+nva(n=0,\xb11,\xb12,\u2026)$, where $vs0$ denotes the searching velocity which matches the target’s radial velocity $vT$, i.e., $|vT\u2212vs0|\u2264\Delta vs/2$. Thereafter, the criterion 2 is introduced to select $vs0$ among $vsn=vs0+nva(n=0,\xb11,\xb12,\u2026)$. On one hand, the RM can be completely corrected when the searching velocity is $vs0$, then optimal integration can be obtained. On the other hand, due to the long-time integration, $vaT>\Delta R$ can be easily satisfied, which indicates that the RM cannot be completely removed when the searching velocities are $vsn=vs0+nva(n=\xb11,\xb12,\u2026)$, and will result in integration loss. Therefore, criterion 2 implies that the final matched velocity can be selected from the set of $vsn$.