Retrodirective beamforming relies on phase conjugation as its core technology to achieve dynamic beam steering in phased arrays. However, as the number of phased array channels increases, the hardware circuit cost and complexity escalate rapidly. This paper proposes a low-cost, low-complexity FPGA-based digital architecture to realize phase conjugation. First, a pre-filter and a comparator are configured as a 1-bit ADC to convert the phase information of the intermediate frequency (IF) pilot signal into a digital pulse delay. Subsequently, 1-bit digital time reversal processing is performed by an FPGA. Finally, a reconstruction filter serving as a 1-bit DAC restores the phase-conjugated sine wave, achieving low-power and low-cost phase conjugation through a simple analog front-end and digital timing processing. Experimental results show that, under conditions of a pilot signal frequency below 1?MHz and a phase resolution of 1°, each transceiver channel requires only 2 I/O pins and 46 bytes of memory resources. Furthermore, the proposed method maintains excellent phase detection and reconstruction accuracy even in complex noise environments, thereby verifying its effectiveness.