The existing Differential 8-Phase Shift-Keying (D8PSK) demodulation methods suffer from long frequency offset estimation time and complex algorithms. To address these issues, a correlation demodulation-based direct phase compensation method is proposed. By optimizing the synchronization timing acquisition and deviation correction algorithms, the demodulation accuracy of D8PSK signals in Very High Frequency Data Broadcast (VDB) systems is enhanced. Field-Programmable Gate Arrays (FPGA) hardware platform testing demonstrates that the method satisfies the bit error rate requirements of VDB receivers under large dynamic range variations.