Signal-out ratio (SCR) in radar systems refers to the ratio of the strength of the desired signal (such as from a target of interest) to the strength of clutter echoes received by the radar. Clutter refers to unwanted radar yields caused by environmental factors such as reflections from land, sea or rain, which can obscure or mask the detection of smaller targets. A higher SCR indicates that the desired signal is stronger relative to the clutter, making it easier to detect and distinguish targets from background noise and clutter. Engineers often aim to maximize SCR through various signal processing techniques and improvements in radar system design to improve target detection capabilities, especially in cluttered environments.
Signal-to-noise ratio (SNR) in radar systems measures the ratio of the resistance of the desired signal (usually from a target) to the resistance of the background noise present in the radar receiver. Noise in radar can result from thermal noise, electronic noise, atmospheric noise, or other sources that introduce unwanted signals into the radar receiver. A higher SNR indicates that the desired signal is larger relative to the background noise, improving the radar’s ability to detect weak signals or targets amid noise. Achieving a high SNR is crucial to improving radar performance in terms of sensitivity, accuracy and reliability, particularly for detecting targets at longer ranges or in adverse environmental conditions where noise levels may be significant.