A BALUN can be any device or structure which is used to "balance" the unbalanced system, like in any RF system. They can be in any form. Suppose, in cases where power flows from an unbalanced line to a balanced line will deteriorate the performance of the whole system. This can be solved by the proper insertion of a balun between the mismatched lines.
Ansys customers with active commercial software licenses can access the
customer portal and submit support questions. You will need your active account number to register.