The range of maritime radar generally varies depending on the type and specifications of the radar system. Standard maritime radars used for navigation and collision avoidance typically have a range of up to 96 nautical miles (about 178 kilometers). However, the effective detection range may be shorter, depending on factors such as target size and reflectivity, weather and sea conditions. Some specialized long-range maritime radars can detect objects at distances exceeding 200 nautical miles (370 kilometers).
The limitation of marine radar includes sensitivity to weather conditions, which can affect its performance. Heavy rain, fog, and sea spray can reduce radar effectiveness by causing attenuation and clutter. Marine radar also has a limited ability to detect small or low-profile objects, such as small boats or buoys, particularly in rough sea conditions. Additionally, the curvature of the Earth limits the radar’s line-of-sight range, meaning that targets beyond the radar horizon cannot be detected. Radar interference from other vessels or electronic systems can also pose challenges.
Range velocity in radar, also known as radial velocity, refers to the rate at which the distance between the radar and a target changes. It is a measure of how quickly a target moves toward or away from the radar. This is determined using the Doppler effect, where a frequency shift in the reflected radar signal indicates the speed of the target relative to the radar. Range rate information is crucial for tracking the movement of targets and can be used to predict their future positions.