* '''[[FDTD_Observable_Types#Scattering_Parameters_and_Port_Characteristics|Port Definition]]''' for calculating the S/Y/Z [[parameters]] and voltage standing wave ratio (VSWR).
* '''Domain Energy''' for calculating the total electric and magnetic energy in the computational domain.
* '''[[#Exciting_Periodic_Structures_Using_Plane_Waves|Periodic Characteristics]]''' for calculating the reflection and transmission coefficients when your periodic structure is excited by a plane wave source.
Of [[EM.Tempo]]'s frequency domain observables, the near fields, far fields and all of their associated [[parameters]] like directivity, RCS, etc., are calculated at a certain single frequency that is specified as part of the definition of the observable. On the other hand, port characteristics like S/Y/Z [[parameters]], VSWR and periodic characteristics like reflection and transmission coefficients, are calculated over the entire specified bandwidth of your project.