System Variants
Last updated
Last updated
There are two current and two obsolete variations of the system:
Mk I. This system has not been sold for several years. Except for packaging, it is essentially identical to and interoperable with the Mk II Baseline system. The Mk I unit is no longer manufactured but software updates continue to be released as appropriate for its capabilities.
Mk II Baseline. This system is obsolete due to lack of demand and replaced by the Mk II Autosync system described below.
Mk II Autosync. This unit automatically synchronizes the system timebases using GPS or GNSS. Synchronization requires both the transmitter and receiver to be (independently) exposed to GPS/GNSS signals at the start of the mission and periodically (every hour or two) during the mission. Additionally, Mk II autosync units can operate on either of two channels allowing two independent ROV systems in the same operating area. The autosync unit allows for multiple receivers to interoperate simultaneously with one transmitter on each channel.
Mk III. This system is similar to a traditional ultra-short baseline (USBL) system. The transceiver sends an interrogation pulse to the transponder, which returns an answer pulse. Slant range is calculated from time of flight, so no timebase synchronization is needed and thus the system can remain submerged indefinitely. Generally, only one Mk III transceiver can operate in an area at one time. Using an ID capability, up to 16 transponders can be used with a transceiver.
Due to supply chain issues, the ROVL MK II and Mk III packages have been redesigned twice. The current package is the "S" package. The "P" package is now end-of-life. Functionally, the "S" and "P" units are identical, and software updates for the "S" package will also apply to the "P" package.