Abstract: An earphone antenna device operable to be connected with a wireless communication terminal device includes: earphone cables, connected with earphone sections, respectively, for supplying audio signals; an audio cable one end of which is connected with the wireless communication terminal device and the other end is connected with the earphone cables; and a coaxial cable one end of which is connected with the wireless communication terminal device and the other end is connected with a pair of string-shaped antenna elements integrated with the earphone cables. The earphone cables are insulated from the antenna elements and the audio cable is insulated from the coaxial cable. This provides a dipole antenna device and an earphone antenna device hardly influenced by noises from the wireless communication terminal device and noises transmitted via the audio cable. Further, a wireless communication terminal device to be connected with the antenna devices is provided.

Abstract: An antenna of the present invention includes a coaxial cable, antenna elements (3a and 3b), and an unbalanced/balanced converter. The unbalanced/balanced converter has a high-pass circuit provided between an input terminal port1 and an output terminal port2 and a low-pass circuit provided between the input terminal port1 and an output terminal port3. Moreover, the high-pass circuit rejects frequencies within a VHF band, and the high-pass circuit and the low-pass circuit both pass frequencies within a UHF band. In response to a signal, inputted to the input terminal port1, which falls within the UHF band, the high-pass circuit and the low-pass circuit output signals that are inverted in phase and equal in amplitude with respect to each other. Therefore, the antenna has high transmission and reception sensitivity in a wide frequency range, i.e., in the VHF and UHF bands. This makes it possible to provide an antenna having high transmission and reception sensitivity in a wide frequency range.

Abstract: A dual channel broadcast receiver includes: a first receiving section having a first antenna, a first low noise amplifier for amplifying a signal received by the first antenna, and a first power divider for dividing a signal fed from the first low noise amplifier into two signals to be outputted therefrom; a second receiving section having a second antenna, a second low noise amplifier for amplifying a signal received by the second antenna, and a second power divider for dividing a signal fed from the second low noise amplifier into two signals to be outputted therefrom; a dual tuner having a first RF input terminal and a second RF input terminal; and a selecting section for, in dual channel reception, selecting and feeding to the first and second RF input terminals either a signal fed from the first receiving section or a signal fed from the second receiving section. The dual channel broadcast receiver does not supply power to an antenna that is not being used.

Abstract: A portable terminal device can suppress/reduce a noise radiated from the portable terminal device, especially more effectively can suppress/reduce adverse effects of a high-frequency noise in VHF/UHF band or higher, so that reception sensitivity of its antenna can be improved effectively. The portable terminal device is arranged such that a sheet member includes at least one of a conductive sheet and a metal deposition sheet inside a housing, an electronic circuit substrate is provided inside the sheet material, and an antenna member is provided outside the sheet member.

Abstract: An antenna of the present invention includes a coaxial cable, antenna elements (3a and 3b), and an unbalanced/balanced converter. The unbalanced/balanced converter has a high-pass circuit provided between an input terminal port1 and an output terminal port2 and a low-pass circuit provided between the input terminal port1 and an output terminal port3. Moreover, the high-pass circuit rejects frequencies within a VHF band, and the high-pass circuit and the low-pass circuit both pass frequencies within a UHF band. In response to a signal, inputted to the input terminal port1, which falls within the UHF band, the high-pass circuit and the low-pass circuit output signals that are inverted in phase and equal in amplitude with respect to each other. Therefore, the antenna has high transmission and reception sensitivity in a wide frequency range, i.e., in the VHF and UHF bands. This makes it possible to provide an antenna having high transmission and reception sensitivity in a wide frequency range.

Abstract: An earphone antenna device operable to be connected with a wireless communication terminal device includes: earphone cables, connected with earphone sections, respectively, for supplying audio signals; an audio cable one end of which is connected with the wireless communication terminal device and the other end is connected with the earphone cables; and a coaxial cable one end of which is connected with the wireless communication terminal device and the other end is connected with a pair of string-shaped antenna elements integrated with the earphone cables. The earphone cables are insulated from the antenna elements and the audio cable is insulated from the coaxial cable. This provides a dipole antenna device and an earphone antenna device hardly influenced by noises from the wireless communication terminal device and noises transmitted via the audio cable. Further, a wireless communication terminal device to be connected with the antenna devices is provided.