This paper proposes half-duplex wireless networks that use acoustic guided waves traveling on or through structures for physically-secure long-range power and data telemetry. Near-maximum power point (nMPPT) is implemented by searching for the optimal transmission frequency in complex acoustic channels. (BPSK) modulated on the power waveform is proposed for downlink. A power-efficient fast uplink is achieved by using NRZ-I data encoding. The proposed half-duplex telemetry approach is experimentally evaluated on a structural health monitoring (SHM) test bed and achieves a power transfer of∼181.8μW at 0.5 m and a BER of 10−4 for a 80 bps downlink, and a BER of 10−4 for a 2 Mbps uplink.