Multi-antenna interferometric array utilizes multiple remote antennas to receive signals simultaneously to improve detection sensitivity and angular resolution. The multi-channel signal combination requires high-precision time synchronization between different channels. A multiplexing multi-channel time synchronization method is proposed. A single digital delay pulse generator is used to regenerate and distribute time signals, and the corresponding measurement and control algorithm is designed. While accurately measuring the transmission delay of multiple fiber optic links, stable time signals are distributed to multiple remote antennas. The experimental results show that the system has a ps level transmission delay measurement accuracy and a 20ps-level time signal distribution accuracy with 25km transmission. This solution can simultaneously support distributed systems with either local or remote digitization, effectively reducing the cost of the distributed synchronization system while ensuring time synchronization precision.