What characterizes an unpaired target in radar data?

An unpaired target in radar data is primarily characterized by the use of radar data only, without any correlating information from other sources such as flight plan data or the input from air traffic control. This situation arises when a radar system detects an object, but there is no corresponding flight plan or other identification data that matches that object. As a result, the target cannot be reliably linked to a known aircraft operation.

This lack of pairing means that the radar system has captured the object's position, speed, and direction of travel based purely on radar reflections, but lacks the context provided by flight plans or communication with air traffic control. Therefore, the identification and tracking of the target rely solely on the radar information at hand.

In contrast, the other options involve aspects that typically relate to paired targets, where additional data helps clarify the identity and intent of the detected objects, making them distinguishable from unpaired targets.