Antennas
Yagi Antenna (3)
- Where no RF energy is fed to these extra elements they are called
parasitic elements and they get power through electromagnetic
coupling with the driven element
- The three element Yagi shown on the previous slide has a parasitic reflector,
a parasitic director and a dipole driven element to which the RF signal is fed
- Parasitic reflectors and directors are respectively about 5% longer
and shorter than the driven element and further directors would usually
get progressively shorter