A digital receiving apparatus includes an analog-to-digital conversion module, a polyphase filter module, a fast Fourier transform module and a phase compensation module, which transforms signals of a target radio source from time domain to frequency domain. It further includes a standard time acquisition module configured to acquire a standard timestamp, a communication module configured to communicate with a host computer, a delay parameter temporary storage module configured to store a to-be-compensated delay parameter, a control enable module configured to generate an enable signal, a delay module configured to perform delay, and a phase parameter generation module configured to temporarily store the to-be-compensated delay parameter and convert it into a phase compensation parameter. The present invention achieves precise synchronous system startup, and the to-be-compensated parameter is updated and aligned in real time to compensate for a time-varying delay difference to accurately track with precision and observe the target radio source.