Discussion Forum

Varying the temperature of the antenna is only relevant to the antenna pattern if it affects the material's RF properties and/or geometry of the antenna. Most (not all) materials don't physically deform much at only 50 deg C as compared to room temperature, so most likely, your concern is limited to the RF properties of the dielectric. Thus, you need to find some published data on the RF properties (e.g., the dielectric constant) at the temperature(s) of interest, then simply plug those values into the material properties specified in your RF model.

Note: If, by some chance, this is an extremely narrowband (high Q) antennna, then physical deformation just may dominate, in which case you should simply adjust the geometry appropriately (and maybe the RF properties too). Now, if there is a lot of RF power applied and a resulting temperature variation across the antenna, and if you care about computing the heating and RF properties self-consistently, then you just might have a multi-physics problem after all...