Boat Radar Guide: Choosing The Right System
How to choose the right radar for your boat or yacht, by Captain Heather Francis.
May 23, 2024
Radar is an invaluable piece of equipment that is often overlooked and underutilized by the average boater. Developed during WWII, radar - which stands for Radio Detection and Ranging - has changed little for boaters until recent years. The reliable pulse radar is still in use, but newer “solid state” radar provides improved performance and ease of install, while being less power hungry and safer for the user. So, how do you know which radar is right for you boat?
The Furuno X-Class radar has several enhancements over previous models. Image by Furuno.
Style & Size
The first consideration when thinking about radar is the size and style of your vessel. For best performance, the radar transmitter needs an unobstructed view and mounted as high up off the water as possible. If you have a smaller vessel without room aloft, either on an arch, mast, or flat top then it will be near impossible to install a radar. Medium sized fishing vessels and sailboats need a mounting location that is free of lines, outriggers, halyards, and other gear that can catch and damage the radar.
Where & How
The next consideration is where and how you use your boat. If you are a weekend warrior who sticks close to home, boats in an area where conditions are consistently calm and clear, and never boat after dark, then a radar might not be for you. If your home waters are in an area that is busy with shipping or other high-speed vessels, is known for fog or quickly changing weather conditions, or you often find yourself navigating in the dark, then radar will be an asset to your vessel. Any vessel heading offshore, or to a foreign port will also benefit from installing a radar.
Compatibility
Not all radars and chart plotters or MFD (multi-function displays) play nice together. We recently ran into this problem when our older chart plotter failed. Updating to a modern MFD meant that we would either lose the functionality of our current radar or have to update to a modern solid-state radar. A costly venture, either way.
Vice versa, if you are considering updating or installing a newer solid-state radar then it is important to find out if your current navigation electronics will communicate with it. Although most new MFD are radar compatible, some of the more basic models are not. As well, some brands will cross talk and other do not.
It is possible, and sometimes recommended, to install a standalone radar screen but most chart plotters and MFD have overlay functions that expand radar function as well as make it easier for the user by combining all functions on one display. Doing some leg work before purchasing will save you a headache during install.
Open Array vs. Dome Radar
Now that you have determined that you need a radar on your vessel, there is a safe place to mount it, and that the radar will integrate with your on-board electronics, it is time to decide whether you should install an open array or a dome radar.
An open array radar is a thin bar that rotates on a centre point, similar to the blades of helicopter. This style of radar is typically seen on ships and large craft that have ample space for the array to rotate uninhibited. The advantage of an open array is that they have a narrow beam width – between 3.5o and 1o - which translates into more accurate target acquisition and greater range. And, because the rotating array is not inhibited by a housing, these radars can be larger and more powerful.
Radar domes, or radomes, enclose the rotating arm inside a housing, usually 18” or 24” in diameter. Their slightly larger beam width – between 3.5o and 7o - means they have good resolution on most targets but may show smaller targets that are next to each other as one object. A radome is a perfect fit for a sailboat as there are no moving parts to snag in the rigging. Radomes also use less power than an open array, another plus for the offshore sailor and smaller power vessels that have limited battery banks.
Old & New Radar Technology
When radar was first developed it used high powered magnetrons to transmit microwave signals. Each signal bounces off an object and returns to the receiver. The time it takes for the “ping” to be sent and received is used to calculate the distance from the radar unit to the object it is detecting. Because these units emit potentially harmful microwaves at high power, is it especially important to be aware of safe working distance guidelines. These radars are accurate enough for the average boater, especially if they are already properly installed in the vessel. Unfortunately, they often do not integrate with newer MFD displays.
Solid State Radar Vs. Magnetron Radar
Newer “solid state” radars no longer use magnetrons to emit a signal. Instead, they transmit a continuous wave signal that changes frequency at a known rate. The FMCW units (Frequency Modulate Continuous Wave) calculate the distance of the object using the difference between the frequencies received back, rather than the “ping” return rate. This “broadband” technology has superior target detection and demands less power to function. This makes them a favourite for fisherman who frequently look for groups of birds to indicate good fishing grounds.
Solid state radars do not need time to warm up before they are fully functional, unlike traditional vacuum tube technology systems—a common complaint for owners of older magnetron radars. And, since they do not emit microwave energy when functioning, they can be mounted close to work areas. Handy for small boat owners who have limited space.
As mentioned, solid state radars have a sharper target acquisition. Most have superior auto-tuning features, eliminating the need to understand how to tune the radar to remove rain and sea clutter and obtain an optimum picture. Many solid-state radars also incorporate Doppler radar technology which colour codes moving targets – red for targets moving toward the vessel, green for targets moving away from the vessel – allowing the user to interpret radar information at a glance.
Here are some additional key benefits of solid state radar systems:
- Lower Power Consumption: Solid-state radars consume less power, making them more energy-efficient and cost-effective to operate over the long term. This is particularly beneficial for mobile and remote installations where power supply might be limited.
- Enhanced Performance: Higher sensitivity and resolution: Solid-state radars can detect smaller and more distant targets with greater accuracy, providing better situational awareness.
- Greater frequency stability: This leads to more precise measurements and less signal distortion, improving overall radar performance.
- Reduced Size and Weight: Solid-state components are typically smaller and lighter than vacuum tubes, resulting in more compact and lightweight radar systems. This makes them suitable for a wider range of applications, including small aircraft and unmanned aerial vehicles (UAVs).
- Digital Signal Processing (DSP): Solid-state radars often incorporate advanced DSP techniques, allowing for more sophisticated signal analysis and target recognition capabilities. This enables better clutter suppression and more accurate target tracking.
- Scalability and Flexibility: Solid-state radar systems are more modular, allowing for easier upgrades and scalability. This makes it simpler to adapt the radar to different operational requirements or integrate new technologies.
- Lower Lifecycle Costs: While the initial investment in solid-state radar technology might be higher, the overall lifecycle costs are lower due to reduced maintenance needs, lower power consumption, and longer operational life.
- Enhanced Safety and Environmental Impact: Solid-state radars generate less electromagnetic interference (EMI), reducing potential health risks and environmental impact. They also produce less heat, reducing the need for extensive cooling systems.
These advantages make solid-state radar systems a preferred choice for modern military, aviation, maritime and weather forecasting applications.
Advantages & Disadvantages of Radar
Radar is good at one thing- it can “see” objects in conditions that we cannot: through rain, fog, and at night. This one simple characteristic will aid in navigation and allow for better collision avoidance. Radar can also detect weather, bands of rain will show up on a radar image, making it easy to avoid unfavourable and potentially dangerous conditions like lightning. It is also a strategic tool in search and rescue operations.
The distance, or range, that a radar can “see” is dependent on two things; how and where it is mounted and the size, height, and material of the object being detected. Ideally, the radar transmitter should be as high on the vessel as possible, with few or no obstructions, and remain level with the surface of the water. This gives the radar signal the greatest potential distance to travel. On vessels like sailboats, a self-levelling swing mount will keep the transmitter parallel to the water even while heeled over.
Objects that are large, dense, and high off the surface of the water will reflect a radar signal stronger than small, low set objects. It should be noted, that materials such as wood and fibreglass do not reflect radar signals as strongly as metal objects. This is why vessels such as sailboats will often carry a radar reflector in their rigging.
Radar is an indispensable tool and modern solid-state technology makes it easier for the boater to install, use, and understand radar.
Frequently Asked Questions
How much does it cost to add radar to a boat?
The cost to add radar to a boat can vary widely depending on the type and brand of the radar system. Generally, recreational boat radar capability can be added to many multi-function displays (MFDs) for around $1,000. Stand-alone radar systems, which offer more features and options, typically start at approximately $1,200 and can increase significantly based on the complexity and capabilities of the system and the install requirements. For the most accurate and up-to-date information, checking with specific marine electronics retailers or manufacturers would be recommended.
What does radar do on a boat?
Boat radar systems are used to detect other vessels and land obstacles, providing crucial bearing and distance information for collision avoidance and navigation at sea.
Can you put radar on a small boat?
There are no size restrictions for installing radar on a boat. As long as there is a stable platform to mount the antenna and sufficient dash space for the display, a radar system can be installed on any size of boat. Keep in mind however, that the radar should be mounted well above the passenger's heads.
Are boat radars safe?
Modern boat radar systems are generally considered safe when properly installed. Recreational marine radar poses minimal risk if mounted above the heads of passengers. However, radar systems emit electromagnetic radiation, which can cause thermal damage to human tissue and may electrify metal wires or ropes. Proper precautions are necessary to avoid electrical shocks or injuries from rotating radar components.
Is there an app like flight radar for boats?
Yes, MarineTraffic is an app that displays near real-time positions of ships and yachts worldwide. It uses the Automatic Identification System (AIS), which provides accurate and constantly updated information about vessel positions, heading, and location. MarineTraffic covers most major ports and shipping routes, allowing users to view vessels on a live map, search for ships, boats, and seaports, and access live wind and 48-hour wind forecasts.
What are the major boat radar brands?
The most popular manufacturers of boat radar include Furuno, Simrad, Lowrance, B&G, Quantum, Raymarine and Garmin.
