Technical Glossary

Angular Accuracy

Angular accuracy refers to the correctness of the true angle of the target relative to the radar system’s azimuth as measured by the radar. In other words, it reflects the difference between the target angular position measured by the radar and the actual angular position. Angular accuracy is influenced by various factors, including antenna beam shape, signal processing algorithms, antenna pointing errors, and external environmental conditions (such as atmospheric refraction).

Angular Resolution

Angular resolution also reflects the radar’s ability to distinguish between two or more closely spaced targets. If two targets are at the same distance and the angular separation between them is less than the radar’s angular resolution, the radar may view them as a single target. Angular resolution primarily depends on the radar antenna size, operating frequency, and the signal processing techniques employed.

Distinction in Definition

Angular accuracy focuses on the correctness of the radar measurement result, i.e., the degree of agreement between the angle information provided by the radar and the actual situation; whereas angular resolution focuses on the radar system’s ability to distinguish adjacent targets in angle.

Radar Interferometric Deformation Accuracy

Radar interferometric deformation accuracy and radar range resolution are two different concepts.

Radar interferometric deformation accuracy refers to the measurement precision achieved when using interferometric techniques to monitor minute deformations of remote target surfaces. The Kinarray S500 slope radar infers changes in the target surface by continuously analyzing the phase difference between two or more radar images acquired at certain time intervals. High accuracy means being able to determine the true deformation of target surfaces such as slopes with very small errors, typically measuring displacement of the target along the radar line of sight with millimeter or sub-millimeter level precision.

Influencing Factors:

• Atmospheric Effects: Phase delays caused by water vapor, temperature changes, etc.
• Terrain Complexity: Complex terrain may lead to issues such as occlusion.
• Coherence: Target surface cover type and stability determine the coherence between SAR images.
• Noise and Other Interference Factors: Additional noise caused by natural phenomena and human activities.

Distinction in Definition

Radar interferometric deformation accuracy focuses on the accuracy of microwave interferometric techniques in measuring target surface deformation, while radar range resolution is about the radar system’s ability to distinguish two or more closely spaced targets.

Interferometric radar is the core technology behind modern deformation monitoring systems. Unlike traditional Synthetic Aperture Radar (InSAR), Kinarray S500 utilizes Digital Real-Aperture Radar technology. By analyzing the phase difference between successive radar measurements, it can detect movements as small as 0.1mm.

Range Accuracy

Range accuracy refers to the degree of correctness of the true distance between the radar and the target as measured by the radar. It reflects the magnitude of the difference between the radar-measured distance value and the actual target distance.

Range Resolution

Range resolution refers to the radar’s ability to distinguish between two or more closely spaced targets. If the distance between two targets is less than the radar’s range resolution, the radar may view them as a single target. Range resolution is primarily determined by the width of the radar’s transmitted pulse or the bandwidth of the frequency modulation.

Distinction in Definition

Range accuracy involves the correctness of the measurement, i.e., the precision of the radar ranging result; whereas range resolution involves the radar’s ability to distinguish adjacent targets.

Slope deformation is a critical safety concern for highways and railways built on or near slopes. Early detection through continuous monitoring enables preventive measures before catastrophic failure occurs.