Radiation resistance and gain of an antenna

I know the meaning of Radiation Intensity of an antenna but how does it help us in estimating the gain of the system?

I don't need any direct relation. I just need to know how they are related.

Thanks in advance.

Radiation intensity is the power radiated per unit solid angle as well it also holds a relationship with directivity, where directivity in a direction is the radiation intensity in that direction over an averaged radiation intensity in all directions.so gain is efficiency times directivity.

so radiation intensity is related to gain in terms of the effective power radiated(power radiated* efficiency) in that directions averaged over all other directions .

Hope that is helpful.Unless you are expecting something else

Regards
ChachitoEL

Actually the question is "radiation resistance" and not "radiation intensity".


Thanks in advance.

The only place where radiation resistance has any effect on gain is in the efficiency part. and elsewhere radiation resistance doesnt have any other influence on the gain.

Due to mismatch between radiation resistance( which for most part has a nebula of definitions associated with it is confusing, to put it simply and in the right manner possible its

The real (or resistive) part of an antenna's feedpoint impedance that includes loss-related resistances.

Hope that helps.
Regards
ChahitoEL