Image Quality Analysis System
The Image Quality Analysis System (IQAS) analyzes the image quality of a point target, or can be used to measure a known point target against a specification.
Image
IQAS measures a known point target against a specification, such as resolution, Peak Side Lobe Ratio (PSLR), or Integrated Side Lobe Ratio (ISLR).
To enable IQAS, click the IQAS button on the tool bar.
Two IQAS dialog boxes will open. One dialog box shows the range (in metres), and the other shows the azimuth angle (in degrees).
Move the IQAS cursor to a target of interest in the sonar view, then click the left mouse button to place the cursor.
Image
The following information will be displayed in the two IQAS dialog boxes.
Resolution, Impulse Response Width (IRW)
The IRW is measured 3 dB down from the top of the Main Lobe of the impulse response. In the range dialog box, the IRW is displayed in pixels and metres. In the azimuth angle dialog box, the IRW is displayed in pixels and degrees.
Peak Side Lobe Ratio (PSLR)
The PSLR is the Peak Side Lobe level in the Near Region relative to the level of the Main Lobe. The unit of measurement is dB.
Integrated Side Lobe Ratio (ISLR)
The ISLR is the ratio of the energy in the Near Region to the energy within the Main Lobe Region. The unit of measurement is dB.