  The solar images at 17 GHz by Nobeyama Radio Heliograph and in X-ray by soft
X-ray telescope (SXT) on board Yohkoh satellite have been of particular
interest for the estimation of solar coronal rotation using flux modulation
approach. These studies established that the solar corona rotates
differentially. The radio images estimate equatorial rotation period lower than
those estimated by the X-ray images. The latitude profiles of the coronal
rotation have temporal variability. The space-time plots of sidereal rotation
period, interestingly, display clear North-South asymmetry. The asymmetry
appears to change its sign in odd and even activity cycles of the Sun.
