Abstract: With the ongoing advancement of sixth-generation mobile communication technology (6G), integrated sensing and communication (ISAC) has garnered significant attention due to its potential for enhancing spectrum efficiency and reducing system costs. Addressing the challenge of cooperative processing between IEEE 802.11ax (Wi-Fi 6) and Frequency Modulated Continuous Wave (FMCW) radar on software-defined radio (SDR) platforms, this paper proposes a system design methodology for ISAC based on SDR platforms. The core of this approach lies in utilizing Doppler shift information obtained from radar sensing to perform frequency offset pre-compensation on the communication receiver, achieving deep synergy between sensing and communication at the signal processing level. The system employs a time-division multiplexing mechanism, enabling FMCW radar pulses and IEEE 802.11ax communication data frames to be transmitted alternately on the same RF link, thereby achieving spectrum sharing. The receiver achieves frame synchronization via a ZC sequence, simultaneously performing radar signal processing and communication signal demodulation. Over-the-air transmission experiments on eNodeX 10F equipment demonstrate the system's effective target perception and data transmission capabilities, with a distance estimation error of 0 m, a velocity estimation error of 2.78 m/s, and a communication bit error rate of 0, validating the effectiveness of the radar-assisted compensation mechanism.