A conventional mobile communications device typically employs a non-directional
antenna so that the antenna offers a satisfactory gain irrespective of how the
device is used, resulting in much radiation of electromagnetic waves from the antenna
toward the human body. Using a directional antenna instead of a non-directional
antenna reduces the radiation of electromagnetic waves from the antenna toward
the human body, but lowers the antenna gain in a stand-by state and thus increases
the risk of failing to receive an incoming call. According to the invention, a
mobile communications device has a non-directional antenna, a directional antenna,
a transmitter/receiver section, a switch for switching states of connection between
the non-directional and directional antennas and the transmitter/receiver section,
and a control circuit for controlling the switch. This reduces the radiation of
electromagnetic waves from the antenna toward the human body but nevertheless ensures
a satisfactory antenna gain even in a stand-by state.
