Apparatus and methods for generating an electromagnetic wave having a wave mode that mitigates interference

A launcher, comprising:

• a generator;
• and
• a circuit coupled to the generator,
• wherein the circuit performs operations including:
• configuring the generator to generate an electromagnetic wave, wherein the electromagnetic wave is modulated to convey data;
• and
• coupling the electromagnetic wave on an outer surface of a transmission medium according to a target wave mode, wherein the target wave mode comprises at least a portion of electric fields of the electromagnetic wave having a spatial alignment that is substantially perpendicular to the outer surface of the transmission medium thereby reducing a propagation loss of the electromagnetic wave when at least the portion of electric fields of the electromagnetic wave enters a substance disposed on the outer surface of the transmission medium.