Garmin's next-generation, 4 kW high-definition GMR 18 xHD dome radar pairs ease of use with advanced open-array features. Its intuitive operation makes modes and settings simple to understand so you can enjoy great performance without a lot of technical know-how.
The GMR 18 xHD delivers higher resolution than Garmin's previous generation 18” dome radars. New Dynamic Auto Gain and Dynamic Sea Filter continually adjust to your surroundings, providing optimal performance in varying conditions. Choose from multiple levels of aggressiveness or use manual gain adjustment. Dual range operation allows fully independent split-screen display of far and close radar views in full 8-bit color (select chartplotters); range of 48 nm. Optional “No Transmit Zone” can protect areas behind the radar from being radiated while providing full forward-looking radar capability. This makes installation more flexible by providing more suitable installation options on your boat.
4 kW high-definition 18” dome radar
Pairs ease of use with advanced open-array features
48 or 24 RPM rotation speeds for fast screen refreshes, auto adjusts as needed based on range
48 Mile max range setting
No complex user settings, easy to install and start using
High definition (outstanding target separation with less screen clutter)
MARPA target tracking/collison avoidance (Requires Heading Sensor, Sold Separately)
Guard zone alarm
8 bit color
Radar overlay support
Dual range support
No Transmit Zone
xHD performance in a dome - High resolution (1440 display spokes vs. 720 on HD domes, draws detail down to ¼ of a degree vs. ½) to provide improved target separation and finer shoreline detail. 8-bit true color helps differentiate large targets from small ones and aids target separation.
Dual Range Operation - Simultaneously view both short and long ranges. You can keep a close eye on your immediate surroundings while also knowing what’s happening farther out. It’s like having 2 radars for the price of one.
Radar Overlay - Overlays radar returns over the top of your navigation charts to provide the best of both GPS and radar. You’ll have greater confidence in the accuracy of your charts when the radar paints the same markers and shorelines. It also helps you discern which radar returns are known charted objects and which are boats or other collision threats.
Dynamic Auto Gain and Sea Filter - Automatically adjusts to your surroundings for optimal performance in all conditions. Dynamic Auto Gain maximizes your ability to see distant targets while limiting excess clutter on the screen. Dynamic Sea Filter reduces the returns caused by nearby waves in heavy seas. You can choose from multiple levels of aggressiveness or use manual gain adjustment.
Mini-Automatic Radar Plotting Aid (MARPA) - Identify and track targets that might pose a collision threat. Targets are manually selected, but then the radar automatically tracks their location, speed, and direction over time. MARPA tells you the closest point of approach and time to that point if you continue on your current route so you can make adjustments for safety. It also alerts you when targets become dangerous or violate a safe proximity of your boat.
In the Box:
GMR 18 xHD
Mounting hardware kit
Power cable (15 m/49.21 ft)
Network cable (15 m/49.21 ft)
Grommet for marine cable
GMR™ 18 xHD Radome Physical and Performance Specifications
50.8 cm diameter, 24.8 cm high
(20 in diameter, 9.75 in high)
GMR™ 18 xHD Radar Specifications
Rotation speed (RPM)
30 W typical
48 W max
24/48 rpm (dual rotation)
11-35 V DC
Click Image to Zoom
Garmin GMR™ 18 xHD Radome
* Oversize item
Due to the large size or weight of this item it is considered oversize and does not qualify for free shipping offers.
Shipping by freight carrier may be required. Click here for more information.