What is the definition of inverted USBL?

Inverted USBL, as the name suggests, is a reversal of the physical locations of the transducer and transponder. The technique for resolving the location of the transponder to the transducer is identical to classic USBL, however, the transducer now resides on the tracked object.

Read the full article “”Untangling USBL – comparing the benefits of USBL-squared (USBL2) with classic and inverted USBL“.

USBL squared explained: Inverted USBL with roving transponder

Image depicting inverted USBL operation, where a transducer is mounted to the tracked object, and a transponder is attached to the surface vessel.

  • The transducer emits an acoustic ping that is returned by the surface vessel transponder.
  • The return ping is processed to provide range and direction information to the transponder.
  • Location of the transponder may be provided by additional means, such as via tether from the surface vessel.
  • Position is attained at each ping cycle, however, full motion data between pings is also being logged.

In the example, the green circles are the pings, the red line is the logged path of motion. Heading of the tracked object is typically provided by a gyrocompass, FOG or similar.

What other terms are related to inverted USBL?

Read more about inverted USBL or related topic


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