An antenna device intended to be used in a communication system of a timepiece, including a substrate; a first antenna circuit made on the substrate and having first and second strands which are connected and having a proximal end and a distal end, extending in parallel, a second antenna circuit made on the substrate and having third and fourth strands which are connected and having a proximal end and a distal end, and extending in parallel, an electrical junction link joining the proximal ends of the first and third strands; a connection portion configured to be bent relative to the electrical junction link, and including a conductive connection which is connected to the electrical junction link and including an electromagnetic shielding of the conductive connection.