Velocity Track



Avoid Collision Hazards

The optional VelocityTrack™ feature for Halo™ radar enables easy identification of approaching obstacles, helping you to avoid dangerous and costly on-water collisions. VelocityTrack™ works with any number of targets, perfect for crowded harbours and waterways. Motion is detected on the first radar sweep, giving you an immediate view when you need it.



Instantly Identify Relative Motion of Radar Targets

VelocityTrack™ technology provides instant feedback on the motion of every target detected by your Halo™ radar system in relation to your boat. Closing or approaching targets are highlighted, and you also have the option to deemphasise diverging or retreating targets. Targets that are stationary relative to your boat are displayed as normal. This simple colour coding works with all of our radar display palettes, so you can continue to use the colour scheme you prefer with added VelocityTrack™ enhancements.



Doppler Effect Detects Motion on the First Sweep

The VelocityTrack™ feature works using the Doppler effect, where radar transmissions are affected by a “phase shift” when bouncing off a moving target. By analysing this shift, Halo™ radar is able to determine whether a target is closing, diverging, or stationary relative to your boat. This means VelocityTrack™ technology is able to deliver information about the motion of targets from the very first radar sweep; combined with Halo™ radar’s InstantOn™ functionality and high-speed operation, the VelocityTrack™ feature provides a clear view of approaching collision hazards in just seconds from standby.


VelocityTrack™ Technology and MARPA

 All Halo™ radar models provide MARPA functionality to track up to ten manually selected targets (20 in dual-range mode). MARPA tracks the motion of selected targets between each sweep of the radar. This provides detailed tracking information for specific targets, including the closest point and time of approach (CPA/TCPA). In contrast, VelocityTrack™ technology determines target motion within a single radar sweep using the Doppler effect. This means the VelocityTrack™ feature is able to display relative motion for all targets on screen. However, it doesn’t offer detailed information such as CPA and TCPA. VelocityTrack™ technology is the perfect complement to MARPA, offering an immediate view of all relative target motion that enables you to pick out relevant targets to track in greater detail, and ignore diverging targets that don’t prevent a collision risk.


Compatible with all Halo™ Radar Models

VelocityTrack works with all Halo™ pulse compression radar models, including HALO-3, HALO-4, and HALO-6, on Simrad NSS evo3, NSS evo2, and NSO evo2 multifunction displays. Simply ensure your Halo radar system and Simrad multifunction display are running the latest software, and purchase a VelocityTrack™ unlock code. No extra hardware is required for this completely online, on-water upgrade. Upgrade codes are available online at or via your local Simrad dealer.

*Note: The VelocityTrack technology requires the latest Halo software. Download it here

Make sure your MFD (NSS evo2, NSS evo3, or NSO evo2) is on the latest software version. Check the downloads tab on the webpage for your particular product

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