far-field hfss

Hi!
During simulation of a PIFA antenna (see fig. 1) I had a question: what is difference between theta component and X component when, for example, a directivity DirTheta and DirX (see fig. 2 and 3) is plotted? These components is codirectional. Why diagrams is different?

These components are not generally co-directional however, there are some positions where they are codirectional (like at φ = 0, θ = 90°). Please try to understand the relation between 3-components of the co-ordiantes (x,y,z and r,θ,φ). You can find the relation in any antenna book.

regards,
shameem

Thank you. It is really obvious. I have a little got confused.