Which of the following factors is least influential on RADAR signal accuracy?

The factor that is least influential on RADAR signal accuracy is target speed. While the speed of a target can impact the Doppler effect and the frequency shift of the RADAR signal, it does not directly affect the fundamental accuracy of the RADAR system. RADAR technology is designed to measure speed accurately, and it can effectively use differences in the frequency of returned signals caused by the target's speed to compute that information.

In contrast, target size, position, and composition are more critical to the accuracy of RADAR signals. The size of the target can influence the strength of the reflected signal; larger targets generally return stronger signals, enhancing detection and accuracy. The position of the target affects the angle of incidence of the RADAR waves and can lead to variations in the signal reflected back to the RADAR unit, which may result in inaccuracies if not correctly accounted for. Meanwhile, the composition of the target determines how well it reflects RADAR waves. Materials that absorb or scatter signals could reduce accuracy, making composition a vital factor in RADAR signal processing.

Overall, while speed is an essential parameter in RADAR technology, it is less critical to the accuracy of the signal compared to these other factors.