Abstract: An antenna apparatus includes: a substrate; an RF ground conductor which is branched to extend in at least two directions and at least a part of which is formed on a surface of the substrate, the RF ground conductor functioning as an antenna ground plane; and an antenna portion, one end of which is connected to the RF ground conductor.

Abstract: An antenna apparatus includes: a substrate; an RF ground conductor which is branched to extend in at least two directions and at least a part of which is formed on a surface of the substrate, the RF ground conductor functioning as an antenna ground plane; and an antenna portion, one end of which is connected to the RF ground conductor.

Abstract: A dielectric composition for high frequencies, which comprises a ceramic component comprising Sr.sub.x (Ni.sub.1/3 Nb.sub.2/3).sub.y O.sub.3 (x/y=0.96-1.06), a ceramic component comprising Sr.sub.x (Ni.sub.1/3 Nb.sub.2/3).sub.y O.sub.3 (x/y=0.96-1.06) as the main constituent and one or more minor constituents which are selected from the group consisting of TiO.sub.2, SrTiO.sub.3 and CaTiO.sub.3 (TiO.sub.2 .ltoreq.25% by mole, SrTiO.sub.3 .ltoreq.6.5% by mole, and CaTiO.sub.3 .ltoreq.13.3% by mole), or a ceramic component comprising Sr.sub.x (Ni.sub.1/3 Nb.sub.2/3).sub.y O.sub.3 (x/y=0.96-1.06) and Ba(M.sup.II.sub.1/3 M.sup.v.sub.2/3)O.sub.3 (M.sup.II is Ni, Mg or Zn, and M.sup.v is Nb or Ta, provided that M.sup.II =Ni, Mg or zn when M.sup.v =Nb, and M.sup.II =Mg or Zn when M.sup.v =Ta) , and 0.1-50% by weight of glass added to the ceramic component.