Patent 10107878 was granted and assigned to Hitachi, Ltd. on October, 2018 by the United States Patent and Trademark Office.
Provided is an antenna such as a TEM-type antenna and a microstrip-type antenna that has rung conductors and a shield conductor to electrically connect and use them. A holding member that maintains a shape of the shield conductor is composed by assembling ribs and thin walls. An inner holding member is a structural material. Holes are provided on at least either one of the shield conductor and the holding member adhered thereto or the inner holding member, which can adjoin conductors from the outside of the cylindrical antenna through the said holes during the antenna production.