Antenna device and portable radio communication device comprising such antenna device

摘要

An antenna device for a portable radio communication device adapted for receiving radio signals comprises a radiating element (10) comprising first and second feeding portions (11, 12) and an amplifier (20) connected to the first and second feeding portions of the radiating element and connectable to a feed device for radio signals (40). By providing the amplifier as a differential amplifier and by co-designing the impedance of the radiating element (10) and the amplifier (20) so as to together provide a predetermined resonance frequency of the antenna device, a small sized internal antenna device is provided while gain is maximized and amplifier noise is minimized.