Discussion Forum

Co-pol and cross-pol depend on what the user considers to be the dominant (typically a preferred direction, the "co-pol") component of Efar and an orthogonal to dominant (typically undesired, "cross-pol") component of Efar. For any particular radiator/antenna, the directions of co- and cross- pol may seem obvious to you, but the code has no idea. So these directions are entirely up to you to define. See: A. Ludwig, "The definition of cross polarization," in IEEE Transactions on Antennas and Propagation, vol. 21, no. 1, pp. 116-119, January 1973.
Plotting emw.normdBEfar does not plot only the co-pol term! It plots the norm of the entire Efar vector. If you want to plot separate co-pol and cross-pol components, then you need to decide what directions correspond to them, and compute the component of the Efar vector in those directions. If these directions do not correspond to simple pre-defined coordinates (like x,y,z...) then you may need to construct the dot product of (emw.Efarx, emw.Efary, emw.Efarz) with a unit vector in the direction of interest to you. (In many cases, the direction of that unit vector may vary with angle, so put some thought into it.) Finally, if you are by some chance decomposing your polarization not into plane polarizations, but into circular (right-handed vs. left-handed) then you will need to prepare an analagous scalar product operation (which may be a little trickier.) But I suspect you would have mentioned that up front, if that was your plan.

Thanks a lot Robert!

Hopefully my directions correspond to simple pre-defined coordinates, so I simply computed the proper components of the Efar vector for the co- and cross-polarization terms.