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This paper describes a highly-integrated CMOS system-on-chip (SoC) for active structural health monitoring (SHM). The chip integrates ultrasonic power and bidirectional half-duplex data transfer, a power management unit (PMU), and an ultrasound transceiver to enable wireless ultrasonically-coupled sensor SHM networks on structures. The PMU includes an active bias-flip rectifier with off-delay compensation, a high-efficiency dual-path DC-DC converter with inductor time-sharing, and five switched-capacitor DC-DC converters to generate multi-level spectrally band-limited pulses for guided-wave SHM. The chip was fabricated in a standard 180 nm process and has a die area of <inline-formula> <tex-math notation="LaTeX">$2\times 2$ </tex-math></inline-formula> mm2. Test results show power conversion efficiency (PCE) &#x003E; 85&#x0025; for the active rectifier, &#x003E; 70&#x0025; for the inductive DC-DC converter, and &#x003E; 60&#x0025; for the switched-capacitor DC-DC converters. Output pulses have a peak-to-sidelobe ratio (PSL) &#x003E; 30 dB and worst-case out-of-band emissions &#x003C; &#x2212;30 dB, respectively. The SoC was integrated with a low-power microcontroller and passive components to realize miniaturized (15 mm <inline-formula> <tex-math notation="LaTeX">$\times 30$ </tex-math></inline-formula> mm) wireless SHM nodes. A set of nodes was deployed on an SHM test-bed (carbon fiber reinforced polymer sheet) representing an airframe panel. Tests on this wireless network confirm both long-range ultrasound power/data transfer and the ability to detect structural damage.