Abstract: Feed point (101) performs unbalanced feeding to an antenna element (102). A parasitic element (104) is provided near the antenna element (102) and a ground plane (103), approximately parallel to the width direction of the ground plane (103). Moreover, the parasitic element (104) is configured in a length to operate as a director when provided on the side of the body with respect to the ground plane (103) during talk time and in a length to operate as a reflector when provided on the opposite side from the body with respect to the ground plane (103). By this means, it is possible to improve gain and reduce the specific absorption rate (SAR) during talk time.

Abstract: The unbalanced feeding antenna element 201 is fed power from one end and placed on the upper surface of the circuit substrate 103. The passive element 202 has open both ends, is set to a length corresponding to a predetermined frequency, placed in substantially parallel to the unbalanced feeding element 201 placed on the circuit substrate 103 at a distance of approximately {fraction (1/10)} or less of a wavelength at a frequency used for transmission/reception. This suppresses the antenna current flowing into the circuit substrate 103 to a minimum level and makes radiation from the passive element 202 dominant compared to radiation from the circuit substrate 103. This makes it possible to suppress a reduction in the antenna gain caused by the human body when the user uses the communication terminal apparatus.

Abstract: An antenna for a cellular wireless apparatus which has the directivity in the direction opposite to the human body and improves the antenna gain. Wireless-apparatus base 10 is a circuit board and feeds power to planar radiation element 20. Planar radiation element 20 is disposed on an upper surface of wireless-apparatus base 10, given power, and transmits and receives radio signals. Parasitic element 30 is on its one end short-circuited with wireless-apparatus base 10, and disposed so that the center axis thereof is parallel to the center axis of planar radiation element 20. A length of parasitic element 30 is set to operate as a reflector.

Abstract: Mobile wireless device antenna configured such that a built-in supplementary antenna compensates for sensitivity deterioration that occurs in a main antenna due to mismatching polarized waves and directivity performance. Built-in antenna 60 is in a reverse L shape, and configured with a linear antenna element perpendicular to a base plane is bent in the middle parallel to the length direction of radio base 30. That is, built-in antenna 60 comprises linear antenna element-vertical part 62 that is perpendicular to the base plane and liner antenna element-horizontal part 64 that extends in the length direction of radio base 30. Of these, linear antenna element-vertical part 62 is connected contact 40b of switch 40 as a power supply element.

Abstract: An antenna apparatus for a radio set capable of reducing influences from the human body, improving the gain and reducing a non-absorption ratio (SAR) without narrowing the communication area. The apparatus according to the present invention is an unbalanced power supply type antenna apparatus for a radio set provided with a power-supplied antenna element 1 and a base plate 3, wherein a tabular parasitic element 7 is placed along the base plate 3 and the length of the parasitic element 7 is set so that the tabular parasitic element 7 operates as a reflector when placed on the human body side and operates as a wave director when placed on the opposite side of the human body.

Abstract: A high gain built-in antenna for a radio communication terminal with less influence from the human body. This built-in antenna for a radio communication terminal includes bar-shaped second passive element 392 facing antenna elements making up dipole antenna 321. The distance between this second passive element 392 and the antenna elements making up dipole antenna 321 is appropriately set in such a way as to widen the band of the input impedance characteristic by changing mutual impedance between second passive element 392 and the antenna elements making up dipole antenna 321.

Abstract: The built-in antenna for radio communication terminals of the present invention includes a loop antenna with a circumference of approximately one wavelength or less placed at an extremely short distance compared with the wavelength from the plane of the terminal board so that its loop plane may be perpendicular to the plane of said terminal bottom board which is opposite to the human body during communication, and a balanced/unbalanced conversion circuit with an impedance conversion function that supplies power to this loop antenna.

Abstract: In a state that a whip antenna is contained in a housing of a cellular phone, a minute space is formed between a feeding spring and an attaching member conductive to a helical antenna base portion, so as to generate electrostatic capacitance, which is equivalent to the impedance characteristic of a mono-pole antenna. Then, electrostatic capacitance and a coil portion of a helical antenna constitute an LC series resonance circuit so as to improve the wide band of the helical antenna.