Metal casing for mobile communication device

A mobile communication device, comprising:

• a case member including a first case portion and a second case portion that is disposed adjacent to said first case portion, each of said first case portion and said second case portion being made of a metallic material, one of said first case portion and said second case portion having a feed-in portion that is configured to be fed with a radio frequency signal, one of said first case portion and said second case portion having a ground portion, wherein said radio frequency signal is fed directly to one of said first case portion and said second case portion;
• a circuit module having an inner surface that abuts a first surface of the first case portion and a corresponding first surface of the second case portion, including
• a substrate,
• a radio frequency circuit that is disposed on said substrate, that is coupled with said feed-in portion, and that is configured to generate the radio frequency signal, and
• a ground conductor that is disposed on said substrate and that is coupled to said ground portion and said first case portion;
• and
• a first radiating arm coupled to said second case portion.