A repeater (190; 190A) comprising a first antenna, a second antenna, and a transceiver, each of the first antenna and the second antenna comprising: a first conductor and a second conductor opposed to each other in a first axis; one or more third conductors positioned between the first conductor and the second conductor and extending in the first axis; a fourth conductor connected to the first conductor and the second conductor and extending in the first axis; and a feeding line electromagnetically connected to any one of the one or more third conductors, the first conductor and the second conductor being capacitively connected through the one or more third conductors, wherein the feeding line of the first antenna is connected to the feeding line of the second antenna through the transceiver, wherein the first antenna is configured to be provided to a first surface of an electrical conductive body, and the second antenna is configured to be provided to a second surface of the electrical conductive body, characterized in that the electrical conductive body is configured to be movable in two states including a stored state and an extended state, and at least one of the first antenna and the second antenna is configured to be interrupted in the stored state. each of the first antenna and the second antenna comprising: a first conductor and a second conductor opposed to each other in a first axis; one or more third conductors positioned between the first conductor and the second conductor and extending in the first axis; a fourth conductor connected to the first conductor and the second conductor and extending in the first axis; and a feeding line electromagnetically connected to any one of the one or more third conductors, the first conductor and the second conductor being capacitively connected through the one or more third conductors, a first conductor and a second conductor opposed to each other in a first axis; one or more third conductors positioned between the first conductor and the second conductor and extending in the first axis; a fourth conductor connected to the first conductor and the second conductor and extending in the first axis; and a feeding line electromagnetically connected to any one of the one or more third conductors, the first conductor and the second conductor being capacitively connected through the one or more third conductors, wherein the feeding line of the first antenna is connected to the feeding line of the second antenna through the transceiver, wherein the first antenna is configured to be provided to a first surface of an electrical conductive body, and the second antenna is configured to be provided to a second surface of the electrical conductive body, the first antenna is configured to be provided to a first surface of an electrical conductive body, and the second antenna is configured to be provided to a second surface of the electrical conductive body, characterized in that the electrical conductive body is configured to be movable in two states including a stored state and an extended state, and at least one of the first antenna and the second antenna is configured to be interrupted in the stored state. the electrical conductive body is configured to be movable in two states including a stored state and an extended state, and at least one of the first antenna and the second antenna is configured to be interrupted in the stored state.