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A portable ultrasonic phased array transmitter with 12 × 12 transmitting elements.High sound pressure level in medium range for efficient presence detection.Reliable privacy maintained security and health monitoring applications.Useful for adverse atmospheric conditions such as darkness and smoke etc.Novel tool for dynamic and accurate health care.An ultrasonic phased array transmitter (PAT) consisting of 12 × 12 elements was designed and fabricated to evaluate its experimental characteristic performance in the medium range of 2 m–10 m for its directivity, pulse width affect and sound pressure level (SPL) measurements as a function of distance from its center in the open air. The SPL was measured at 2 m, 5 m, and 10 m distances as 135 dB, 126 dB and 68 dB, respectively. The experimentally measured directivity patterns were found in good agreement with the theoretical results obtained by using MATLAB simulations. The SPL showed negligible change as a function of the ultrasonic pulse widths such as 0.5 ms, 1 ms and 2 ms. The SPL and directivity of the PAT at 2 m distance were measured for ultrasonic pulse width of 0.1 ms only while as at 10 m distance these were measured for the ultrasonic pulse widths of 0.5 ms, 1 ms and 2 ms. The present investigations on the PAT characteristics are expected to be useful for its industrial, scientific and biomedical applications, e.g., robotics for 3D range imaging with improved and efficient object presence sensing as well as nondestructive health monitoring.