Often impedance matching is employed to decrease radome scattering loss over some particular frequency band. With the scattering loss near zero over the impedance matching bandwidth, transmission loss approaches the ideal wall insertion loss. Generally, a radome operational frequency band occurs where the wall insertion loss is very low. One problem with a solid laminate wall is that its insertion loss increases with frequency. In addition, this sandwich construction frequency matching technique provides excellent thermal insulation along with minimal transmission loss.
General practice is to place the cut-off frequency above the highest signal frequency component.
After exposure to sunlight and the environment, microscopic damage is caused to standard radome surfaces. Such negative rain induced effects often occur when system performance mandates perfection. To help reduce the problems associated with microscopic surface damage, AFC has pioneered hydrophobic surface coatings . In stead of rain sheeting, a hydrophobic surface causes the radome to remain dryer, water to bead and run off in rivulets. With the radome surface effectively dryer, substantial improvements in wet transmission loss and noise temperature result in a superior performing radome.