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Calibration difference for nominal elevation angle difference

This picture is the most useful one and should be used in the first place. It displays the calibration difference assuming that the nominal elevation angles are correct. Use this unless there are grounds to suspect that the angles are not as commanded. Please note that each point is an average over two weeks. The time given is the end time of the analysis window.

Red colour is used to denote points with calibration difference exceeding 2 dB in absolute value.

Elevation angle difference based on the analysis

This picture is used to find out what the actual difference of the elevation angles is. The nominal difference is printed in the title, and marked with green line in the picture. The picture should be studied with care. Rapid changes are usually artifacts caused by the rainfall violating the assumed homogeneity of the rainfall. Longterm changes, extending over several weeks, possibly indicate that the angles are changing. Please note that each point is an average over two weeks.

Not all points are shown. If the angular difference given by the analysis is too large (0.57 in absolute value) the analysis result is regarded as unreliable and not shown.

Calibration difference based on the analysis

This picture is needed, if the nominal elevation angle difference is not correct. When the correct angular difference is found from the elevation angle picture, the calibration difference can be estimated from this picture. Please use then such times where the elevation angle difference, in the second picture, is close to the estimated value.

The time instants which are excluded from the elevation angle picure are also excluded from this one.