This article examines the potential of the Y-type hexagonal ferrites , BaSrCo2 x NixFe12O22, as passive
microwave absorbing materials and magneto-dielectric antenna substrates.To this effect,wein-
vestigated the electromagnetic properties of the fabricated samples upto 18 GHz,in conjunction with the
composition, microstructure and static magnetic characteristics. It was found that the Ni substitution
yields theincreaseofpermeability μ* andpermittivity ε* asaconsequenceoftheweakermagneto-
crystalline anisotropyandenhanceddielectricorientationpolarization.Byvirtueoftheirdifferent ε* and
μ* spectra,theCo-richhexagonalferritesappearasappropriatefornarrowband-yettunable-reflection
reduction inthe2.6–18GHzrange(420 dB),whereaswithNiadditionwidebandattenuationofthe
transmittedwaves(420 dB)isattainedinthe7–18GHzband.Inaddition,thepersistenceofhighre-
fractiveindexupto1GHzenablestheutilizationofthesehexagonalferritesinUHFantennadesignswith
smaller dimensions.Amongthem,designswithCo2-Ycompoundareliabletohigherradiationefficiency,
while Ni2-Yfavourstheachievementofwiderbandwidth.Onthisbasis,theperformanceoftheproduced
materials inhighfrequencyapplicationsisevaluatedandcertainimprovementdirectionsareindicated