Methods for determining calibration parameters to correct for frequency responses of one or more dielectric waveguides coupling a control unit to a first antenna node or to a series of antenna nodes that includes the first antenna node. An example method comprises transmitting, via a first dielectric waveguide coupling the control unit to the first antenna node, a radiofrequency (RF) test signal having a signal bandwidth covering a bandwidth of interest. The method further comprises receiving, via a second dielectric waveguide coupling the control unit to the first antenna node, a looped-back version of the transmitted RF test signal, and estimating a first one-way frequency response corresponding to the first (or second) dielectric waveguide, based on the RF test signal and the received loop-back version of the transmitted RF test signal.