20090011721 | Radio communication device - A radio communication device includes a spherical case, an outer case, and a liquid or gelled substance. The spherical case has a circuit portion for radio communication and a balance anchor located therein. The circuit portion includes a power supply device which has a solar cell and a secondary battery. The outer case has the spherical case located therein. The substance is contained between the spherical case and the outer case. At least a portion of the spherical case which is used as a light entering path, the outer case and the substance are transmissive to light in an optical wavelength range with which the solar cell can generate electricity. Friction between the spherical case and the substance is small so that the spherical case is rotatable within the outer case by the movement of the balance anchor by gravity. | 01-08-2009 |