Gong, Cihun-SiyongCihun-SiyongGongHuang, Hsin-JouHsin-JouHuangLiu, Hao-LiHao-LiLiu2026-02-232026-02-232026-02https://www.scopus.com/record/display.uri?eid=2-s2.0-105025457689&origin=resultslisthttps://scholars.lib.ntu.edu.tw/handle/123456789/735953This letter proposes an advanced platform that can concurrently transmit and receive dual-mode parallelism, as well as instant switching functions, and supports large-scale expansion of air-coupling phase array systems. Unlike most systems in the existing literature that only have emission functions and are limited by low voltage drive, this letter adopts a custom analog high-voltage amplifier circuit that can provide driving voltage up to 40 Vpp while maintaining low power consumption. This letter proposes a system architecture that uses primary–secondary field-programmable gate array series as the core, and is equipped with USB3.0 and serial peripheral interface high-speed communication, which can flexibly support multimodule expansion and achieve array sizes of up to at least 400 channels or more. The actual measurement results show that this system can form a clear, focused sound field at 10 and 20 cm focal lengths, with a maximum sound pressure approaching 5 kPa, and is highly consistent with the simulation results. In addition, the system successfully realizes echo reception and B-mode imaging, verifying the functionality of synchronously running bidirectional operations. Power analysis also proves that under high channel count operation, the system needs only about 20 W of power to maintain a stable output when running 100 channels. Compared with the existing literature, this system has significant advantages in operating voltage, bidirectional function, and power consumption efficiency, providing extremely competitive technological development for air-borne in human–computer interaction, tactile interface, and directional audio applications.falseairborne ultrasounddual modefield-programmable gate array (FPGA)hapticshuman–machine interfacemodularphased arrayreconfigurableSensor systemsultrasonic array systemultrasound imagingjournal article10.1109/lsens.2025.36445972-s2.0-105025457689