Ultra Short Baseline (USBL) Hydroacoustic positioning is determined by the:

The determination of Ultra Short Baseline (USBL) hydroacoustic positioning is based on the time difference of signal arrival from a pinger beacon to hydrophones. This technique involves using an underwater positioning system that listens for signals emitted by a pinger attached to a submerged object, such as a remotely operated vehicle (ROV) or underwater survey equipment.

The USBL system calculates the distance and position of the pinger by measuring the time it takes for the sonar signals to travel from the pinger to multiple hydrophones. Since the speed of sound in water is known, the system can accurately determine the range to the pinger based on the time delay between the transmitted signal and its reception by the hydrophones. This elapsed time is then converted into a distance measurement, allowing for precise positioning of underwater objects.

In understanding the other options, while angulation of signals could play a role in establishing position in more complex systems, it is not the foundational method for USBL positioning. The acoustic properties of water and the propagation speed of sonar waves, though relevant to underwater acoustics, are secondary factors that support the functioning of the USBL system but do not directly define how positioning is achieved through USBL. Hence, focusing on the time difference of signal