Consider a parabolic reflector antenna with diameter D$=4$D$=4$ m which is modelled as a uniform circular aperture. The antenna is used as part of a long$-$distance S$-$band radar system operating at a center frequency f$0$f$0=3$ GHz$.$ The field strength in the uniform circular aperture E$0$E$0=100$ V$/$m$.$Determine the Electric field strength $($in V$/$m$)$ of the component of the Electric field at a distance r$=10$r$=10$ km from the antenna with $=$HPBW$2$$=2$HPBW$$ and $=45$ degrees.