The present invention relates to a portable compact antenna comprising a first radiating element of the dipole type, operating in a first frequency band and formed by a first and at least one second conductive arm supplied differentially, the first arm, called cold arm, forming at least one cover for an electronic card wherein the second arm, called hot arm, is extended by a conductive wire element, the length of the assembly formed by the first arm, the second arm and the wire element being chosen to provide an operation in a second frequency band.