An arrangement to control an antenna arrangement in a magnetic resonance examination representatively has a device for signal splitting. This device has an input and a first input and a second output. A radio-frequency transmission signal is supplied at the input. The device for signal splitting has phase-shaping components with which the transmission signal supplied via the input is divided into a first transmission signal for the first output and a second transmission signal for the second output. A phase difference between the first transmission signal and the second transmission signal can be adjusted by the phase-shaping components. An antenna arrangement is provided that has a first and second connections and that is fashioned to radiate a circularly-polarized transmission signal as soon as the two transmission signals with a phase difference of 90.degree. are present at both connections. Each output of the device for signal splitting is connected with an associated connection of the antenna arrangement. The device for signal splitting has switchable components with which selected ones of the phase-shaping components can be activated or deactivated in order to alter the phase difference.