be for example made of a single metal or an alloy material of titanium aluminum silver copper nickel iron cobalt magnesium or platinum in addition in each embodiment of the present invention each antenna is electrically coupled to respective corresponding signal transceiver circuit so as to perform the transferring and processing operations of the wireless signal the metal layer 12 is disposed on the second surface 102 of the dielectric layer 10 to serve as the antenna signal feeding portion and the antenna radiation portion of the electronic device and the antenna signal feeding portion is a 50 ohm microstrip line the metal layer 12 can be for example made of a single metal or an alloy material of titanium aluminum silver copper nickel iron cobalt magnesium or platinum referring to fig1 b a schematic sectional structural view of a second embodiment according to the present invention is shown the difference between the second embodiment and the first embodiment is that both of the metal case 11 and the metal layer 12 in the second embodiment are disposed on the first surface 101 of the dielectric layer 10 the remaining material parts in the second embodiment are the same as those in the first embodiment so they are not described here referring to fig1 c a schematic sectional structural view of a third embodiment according to the present invention.