SDO/AIA image taken at 171 Å on 2011 March 22 at 11:28 UT showing the coronal configuration during the type U radio emission. The radio source positions were imaged by the NRH at the intensity peaks at 298.7, 327.0, and 360.8 MHz. The colored contours represent 99.0%, 99.5%, and 99.9% of the corresponding intensity maximum and the three frequencies are plotted in blue, green, and red, respectively. The black solid curve represents the modeled loop, while the black filled circle indicates the apex of the loop.