Abstract: An antenna apparatus includes a ground substrate, a feeding point provided on the ground substrate, a first loop antenna of which one end is electrically connected to the feeding point and of which another end is electrically connected to the ground substrate and moreover which operates at a first frequency, and a second loop antenna of which both ends are respectively connected to a first end point and a second end point of the first loop antenna and which operates at a second frequency. A space between the first end point and the second end point forms a gap with a range in which the first loop antenna is capable of resonating at the first frequency.

Abstract: An antenna apparatus includes a ground substrate, a feeding point provided on the ground substrate, a first loop antenna of which one end is electrically connected to the feeding point and of which another end is electrically connected to the ground substrate and moreover which operates at a first frequency, and a second loop antenna of which both ends are respectively connected to a first end point and a second end point of the first loop antenna and which operates at a second frequency. A space between the first end point and the second end point forms a gap with a range in which the first loop antenna is capable of resonating at the first frequency.

Abstract: An antenna apparatus includes a ground substrate, a feeding point provided on the ground substrate, a first conductor device of which one end is electrically connected to the feeding point and which has a plate shape being parallel to the ground substrate, a second conductor device which is arranged between the first conductor device and the ground substrate, of which one end is electrically connected to the ground substrate, and which has a plate shape being parallel to the ground substrate and a connecting portion which electrically connects another end of the first conductor device and another end of the second conductor device to each other. A width of the first conductor device is wider than a width of the second conductor device. Lengths of the first conductor device and the second conductor device are ½ of a wavelength of a radio wave for operating the antenna apparatus.

Abstract: An antenna device includes a ground plane that includes an edge and a surface, a protruding metallic member that includes a first connecting part and a second connecting part coupled to the ground plane, protrudes from the edge, and constructs a first loop including the edge, and a T-shaped antenna element that extends from a feeding point to a first end and a second end along the edge, the feeding point being disposed in the vicinity of the surface between the first connecting part and the second connecting part of the first loop, wherein a length of the first loop corresponds to an electric length of one wavelength in a first frequency, and corresponds to an electric length of two wavelengths in a second frequency that is a second order harmonic of the first frequency.

Abstract: An antenna device includes: a ground plane which has an edge side; a metal member arranged along the edge side of the ground plane; a first connection line which couples the metal member and the ground plane; a second connection line which couples the metal member and the ground plane; and a power feeding element which has a power feeding point, extends along the metal member from the power feeding point between the first connection line and the second connection line, and is electromagnetic-field-coupled to the metal member.

Abstract: An antenna device includes a ground plane having an edge side, a monopole antenna element that communicates in a first frequency, and that has a first feeding point, a first line that extends from the first feeding point in a direction away from the edge side of the ground plane, and a second line that is coupled to the first line and extends along the edge side, a plurality of dipole feeding elements that communicate at a second frequency higher than the first frequency, and are disposed, with respect to the ground plane, in positions that match the positions of the second line with respect to the ground plane, and a plurality of reflectors that reflect electromagnetic waves radiated by the plurality of feeding elements, and are disposed respectively in correspondence to the plurality of feeding elements between the ground plane and the plurality of feeding elements.

Abstract: A multiband antenna includes a ground conductor, a first conductor disposed at a predetermined distance from the ground conductor, formed linearly, and configured to have a length to resonate at first and second frequencies, the first conductor including a power feeding point, a second conductor coupled to the first conductor at both ends of the second conductor, disposed closer to a side of the ground conductor than the first conductor, formed linearly, and configured to form a slit between the first and second conductors and resonate together with the first conductor at a third frequency, and a third conductor provided at one or more ends of the first conductor and configured to extend from a first end of the one or more ends to the side of the ground conductor to be electromagnetically coupled to the ground conductor at the third frequency, wherein the conductors has conductivity.

Abstract: An antenna device includes: a ground plane having an edge; a matching circuit; and a T-shaped antenna element including a first element and a second element extending from a feed point to a first and second end parts. The first element has a resonance frequency that is higher than a first frequency. The second element has a resonance frequency between a second frequency and a third frequency. A first value obtained by dividing a length from a corresponding point to a first bend part by the first wavelength is less than or equal to a second value obtained by dividing a length from the corresponding point to a second bend part by the second wavelength. An imaginary component of an impedance of the matching circuit takes a positive value at the first frequency and the second frequency and takes a negative value at the third frequency.

Abstract: The wireless communication device has a first radiation element, which includes a first line path being extended between a first end and a second end and performs communication at a first frequency. The device also has a second radiating element coupled to the first radiating element and resonating at a second frequency, which element has a second line path extending from a first connecting portion connected to the sheet metal to a third end portion near the first end portion, and a third path line extending from an intermediate point between the first connecting portion and the third end portion to the fourth end portion. And a power supply circuit for a third frequency is connected to the fourth end via a cutoff circuit which cuts off the second frequency. With this configuration, the wireless communication device enables the communication in more frequency bands.

Abstract: An antenna device includes a ground plane that includes an edge and a surface, a protruding metallic member that includes a first connecting part and a second connecting part coupled to the ground plane, protrudes from the edge, and constructs a first loop including the edge, and a T-shaped antenna element that extends from a feeding point to a first end and a second end along the edge, the feeding point being disposed in the vicinity of the surface between the first connecting part and the second connecting part of the first loop, wherein a length of the first loop corresponds to an electric length of one wavelength in a first frequency, and corresponds to an electric length of two wavelengths in a second frequency that is a second order harmonic of the first frequency.

Abstract: A multiband antenna includes a ground conductor, a first conductor disposed at a predetermined distance from the ground conductor, formed linearly, and configured to have a length to resonate at first and second frequencies, the first conductor including a power feeding point, a second conductor coupled to the first conductor at both ends of the second conductor, disposed closer to a side of the ground conductor than the first conductor, formed linearly, and configured to form a slit between the first and second conductors and resonate together with the first conductor at a third frequency, and a third conductor provided at one or more ends of the first conductor and configured to extend from a first end of the one or more ends to the side of the ground conductor to be electromagnetically coupled to the ground conductor at the third frequency, wherein the conductors has conductivity.

Abstract: An antenna device includes: a ground plane which has an edge side; a metal member arranged along the edge side of the ground plane; a first connection line which couples the metal member and the ground plane; a second connection line which couples the metal member and the ground plane; and a power feeding element which has a power feeding point, extends along the metal member from the power feeding point between the first connection line and the second connection line, and is electromagnetic-field-coupled to the metal member.

Abstract: The wireless communication device has a first radiation element, which includes a first line path being extended between a first end and a second end and performs communication at a first frequency. The device also has a second radiating element coupled to the first radiating element and resonating at a second frequency, which element has a second line path extending from a first connecting portion connected to the sheet metal to a third end portion near the first end portion, and a third path line extending from an intermediate point between the first connecting portion and the third end portion to the fourth end portion. And a power supply circuit for a third frequency is connected to the fourth end via a cutoff circuit which cuts off the second frequency. With this configuration, the wireless communication device enables the communication in more frequency bands.

Abstract: An antenna device includes: a ground plane having an edge; a matching circuit; and a T-shaped antenna element including a first element and a second element extending from a feed point to a first and second end parts. The first element has a resonance frequency that is higher than a first frequency. The second element has a resonance frequency between a second frequency and a third frequency. A first value obtained by dividing a length from a corresponding point to a first bend part by the first wavelength is less than or equal to a second value obtained by dividing a length from the corresponding point to a second bend part by the second wavelength. An imaginary component of an impedance of the matching circuit takes a positive value at the first frequency and the second frequency and takes a negative value at the third frequency.

Abstract: An antenna apparatus includes: a ground plane having a slit extending from an edge to an inside first point and extending, along the edge, to a second point; a first antenna element having a first feed point and a first open end, the first feed point being arranged at an opposite side of an area surrounded by the slit and the edge with respect to the slit, the first antennae element extending from the first feed point to a first bend part at a first height position and extending to the first open end; and a second antenna element having a second feed point, arranged in the area, and a second open end, and extending from the second feed point to a second bend part at a second height position, extending to the second open end, and crossing, at a second open end side, the slit.

Abstract: An antenna design method executed by a computer includes creating an antenna model including an antenna which includes a plurality of antenna elements and matching circuits which are respectively connected to the plurality of antenna elements and which comprise a matching element including a parasitic reactance and a loss resistance; obtaining a characteristic of the antenna and a characteristic of the matching element; calculating a characteristic of the created antenna model using the obtained characteristic of the antenna and the characteristic of the matching element; judging whether or not the calculated characteristic of the antenna model satisfies a standard value; and displaying result of the judgment.

Abstract: An antenna designing method, performed by a computer, includes: inputting a first antenna characteristic of an antenna; creating an antenna model that includes the antenna and a matching circuit which is connected to the antenna and is formed by a matching element including parasitic reactance and loss resistance; calculating a second antenna characteristic of the created antenna model by using the first antenna characteristic; determining whether or not the calculated second antenna characteristic satisfies a desired standard value; and displaying a determined result.

Abstract: An antenna design method executed by a computer includes creating an antenna model including an antenna which includes a plurality of antenna elements and matching circuits which are respectively connected to the plurality of antenna elements and which comprise a matching element including a parasitic reactance and a loss resistance; obtaining a characteristic of the antenna and a characteristic of the matching element; calculating a characteristic of the created antenna model using the obtained characteristic of the antenna and the characteristic of the matching element; judging whether or not the calculated characteristic of the antenna model satisfies a standard value; and displaying result of the judgment.

Abstract: A folding type portable radio machine, includes a chassis part formed by a first chassis and a second chassis, the second chassis being foldably connected to the first chassis. The chassis part includes a conductive part having conductivity whose full length is an approximately half wave length (?/2) of a using frequency of the radio machine, and an electric notch.

Abstract: A radio communication device that outputs an alarm when a reception level of a radio wave from a wireless unit is less than a threshold value, includes a reception level measuring section for measuring the reception level of the radio wave transmitted from the wireless unit at certain times. A threshold value setting section for setting a first threshold value or a second threshold value less than the first threshold value based on a difference between the reception level of the radio wave measured a previous time and the reception level of the radio wave measured a subsequent time. An alarm output requesting section for causing an alarm output section to output an alarm if the reception level of the radio wave measured a subsequent time is less than the first threshold value or the second threshold value.