Abstract: A communication device includes a ground unit, a dielectric plate, a communication circuit, a conductor, and a capacitance element. The ground unit has a reference potential applied to the ground unit. The dielectric plate is provided on the ground unit. The communication circuit is provided on the dielectric plate and performs a transmission and a reception of a signal. The conductor is connected to the communication circuit. An end of the capacitance element is connected to the conductor. An another end of the capacitance element is connected to the ground unit. A capacitance of the capacitance element is smaller than a capacitance formed between the conductor and the ground unit. The capacitance of the capacitance element is bigger than a capacitance formed between the conductor and the ground unit being caused by a human body touching or approximating to the conductor.

Abstract: An antenna device includes a substrate; a first linear conductive element that is disposed on the substrate so as to have a loop shape line-symmetric with respect to a first straight line and a second straight line that is orthogonal to the first straight line, the first linear conductive element having a first electrical length between intersections of the first linear conductive element and the second straight line that is an integer multiple of a wavelength at a resonance frequency; and a second linear conductive element that is disposed on the substrate and is substantially parallel to the second straight line, the second linear conductive element having a second electrical length that is a half wavelength of the wavelength at the resonance frequency.

Abstract: An antenna device includes a substrate, and a linear conductive element disposed on the substrate, the linear conductive element having a loop shape in line symmetry with respect to a first straight line and a second straight line perpendicular to the first straight line, respectively, an electrical length between intersection points of the linear conductive element and the first straight line is an integer multiple of a wavelength in a resonance frequency.

Abstract: A communication device includes a ground unit, a dielectric plate, a communication circuit, a conductor, and a capacitance element. The ground unit has a reference potential applied to the ground unit. The dielectric plate is provided on the ground unit. The communication circuit is provided on the dielectric plate and performs a transmission and a reception of a signal. The conductor is connected to the communication circuit. An end of the capacitance element is connected to the conductor. An another end of the capacitance element is connected to the ground unit. A capacitance of the capacitance element is smaller than a capacitance formed between the conductor and the ground unit. The capacitance of the capacitance element is bigger than a capacitance formed between the conductor and the ground unit being caused by a human body touching or approximating to the conductor.

Abstract: An antenna device includes a finite ground plane that includes a linear side, a first conductor plate that faces the finite ground plane and includes a side corresponding to the side of the finite ground plane and having a length of substantially a ? wavelength or less, and a conductor line that includes one end connected to the side of the first conductor plate and the other end short-circuited to one end portion of the side of the finite ground plane. The antenna device further includes a second conductor plate that faces the finite ground plane, includes a side corresponding to the side of the finite ground plane and having a length of substantially a ? wavelength or less, and is arranged to be adjacent to the first conductor plate to perform capacitive coupling with the first conductor plate and a feed line that includes one end connected to the side of the second conductor plate and the other end connected to the other end portion of the side of the finite ground plane.

Abstract: According to an embodiment, a communication apparatus includes a substrate, a first communication unit, a first signal line, a first terminal, a second signal line, a variable capacitance portion, and an inductor portion. The substrate is provided with a reference potential electrode. The first communication unit transmits and receives. One end of the first signal line is connected to the first communication unit. The first terminal is connected to the other end of the first signal line. The second signal line is connected to the first signal line through the first terminal. One end of the variable capacitance portion is connected to the other end of the second signal line. One end of the inductor portion is connected to the other end of the variable capacitance portion. The communication apparatus executes communication through a living body.

Abstract: According to one embodiment, a communication apparatus includes a substrate, a communication circuit, a first signal line, an insulator, and a first conductor. The substrate includes a ground. The communication circuit is provided on the substrate. The first signal line is connected to the communication circuit and is electrically connected to the outer surface of the first conductor. The insulator surrounds the substrate. The first conductor surrounds the insulator.

Abstract: According to one embodiment, a living body detection sensor includes a substrate, a signal generation unit, a first conductor, a second conductor, and a detection unit. The substrate includes a reference potential electrode and a dielectric material. The signal generation unit generates a first signal, the signal generation unit is provided on the substrate. The first conductor receives the first signal, the first conductor is separated from the substrate. The second conductor t receive the first signal sent from the first conductor, the second conductor is separated from the substrate. The detection unit receives the first signal outputted from the second conductor and detects an electric field produced between the first conductor and the second conductor, the detection unit is provided on the substrate. The living body detection sensor detects whether a living body is close to the living body detection sensor.

Abstract: According to an embodiment, a communication apparatus includes a substrate, a first communication unit, a first signal line, a first terminal, a second signal line, a variable capacitance portion, and an inductor portion. The substrate is provided with a reference potential electrode. The first communication unit transmits and receives. One end of the first signal line is connected to the first communication unit. The first terminal is connected to the other end of the first signal line. The second signal line is connected to the first signal line through the first terminal. One end of the variable capacitance portion is connected to the other end of the second signal line. One end of the inductor portion is connected to the other end of the variable capacitance portion. The communication apparatus executes communication through a living body.

Abstract: According to an embodiment, a communication apparatus communicates through a living body. One end of a first signal line is connected to the communication unit. A terminal is connected to the other end of the first signal line. One end of a second signal line is connected to the terminal. The second signal line is connected to the first signal line through the terminal. A first signal electrode is connected to the other end of the second signal line. One end of a third signal line is connected to the terminal. The third signal line is connected to the first signal line through the terminal. One end of a magnetic field sensor is connected to the other end of the third signal line. The other end of the magnetic field sensor is connected to a reference potential electrode.

Abstract: According to an embodiment, a first communication equipment includes a first communication unit configured to transmit and receive a signal, and a first conductor electrically connected to the first communication unit. A second communication equipment includes a second conductor, a third conductor located in parallel with the second conductor and set to first reference potential, a fourth conductor separated from the second conductor and located substantially orthogonal to the second conductor, a fifth conductor located in parallel with the fourth conductor and set to the first reference potential, a first detection unit configured to detect a first differential output between signal outputs respectively observed by the second conductor and the fourth conductor, and a second communication unit configured to receive the first differential output and transmit and receives a signal.

Abstract: According to one embodiment, the signal electrode is disposed on the first principal surface side of the substrate and is connected to the other end of the second signal line. The housing covers and accommodates therein the substrate, the communication unit, the first signal line, the terminal, the second signal line, and the signal electrode. The conductive material is arranged on an outer side of the housing so as to be opposite to the signal electrode, and includes an outer peripheral portion extended outward beyond an outer periphery of the signal electrode. The communication apparatus carries out data communication via a living body.

Abstract: According to an embodiment, the first signal line is provided on the substrate and has one end connected to the communication unit. The coaxial line is provided by a surface side of the substrate and includes second and third signal lines. The third signal line is provided at an outside of the second signal line through a dielectric. One end of the second signal line is connected to the other end of the first signal line. One end of the third signal line is connected to the ground electrode though a via. The electrode unit includes a reference potential electrode and a signal electrode. The signal electrode is provided around the reference potential electrode with a space left in between. The reference potential electrode is connected to the other end of the third signal line whereas the signal electrode is connected to the other end of the second signal line.

Abstract: In one embodiment, a human body communication apparatus includes a first human body communication terminal carried by a person, a second human body communication terminal and an authentication unit included in the first or second human body communication terminal. The first human body communication terminal includes a first detection unit to detect first living body physiological information of the carrying person. The second human body communication terminal includes a human body contact sensor and a second detection unit to detect second living body physiological information of the person who touches the human body contact sensor. The authentication unit acquires the first and second living body physiological information and determines a correlation between the first and second living body physiological information to permit communication between the first and second human body communication terminals in accordance with the correlation.

Abstract: According to one embodiment, a living body detection sensor includes a substrate, a signal generation unit, a first conductor, a second conductor, and a detection unit. The substrate includes a reference potential electrode and a dielectric material. The signal generation unit generates a first signal, the signal generation unit is provided on the substrate. The first conductor receives the first signal, the first conductor is separated from the substrate. The second conductor t receive the first signal sent from the first conductor, the second conductor is separated from the substrate. The detection unit receives the first signal outputted from the second conductor and detects an electric field produced between the first conductor and the second conductor, the detection unit is provided on the substrate. The living body detection sensor detects whether a living body is close to the living body detection sensor.

Abstract: According to an embodiment, a first communication equipment includes a first communication unit configured to transmit and receive a signal, and a first conductor electrically connected to the first communication unit. A second communication equipment includes a second conductor, a third conductor located in parallel with the second conductor and set to first reference potential, a fourth conductor separated from the second conductor and located substantially orthogonal to the second conductor, a fifth conductor located in parallel with the fourth conductor and set to the first reference potential, a first detection unit configured to detect a first differential output between signal outputs respectively observed by the second conductor and the fourth conductor, and a second communication unit configured to receive the first differential output and transmit and receives a signal.

Abstract: In the embodiment, a communication device is provided including a substrate, an antenna mounted on the substrate, a first communication unit which transmits or receives a first signal via the antenna, a terminal provided on the substrate, a signal wire one end of which is connected to the terminal, a conductor plate connected to the other end of the signal wire, and a second communication unit which transmits or receives a second signal via the conductor plate. A sum length of a line length of the signal wire and half a circumferential length of the conductor plate is equal to integral times of half the wavelength of the resonance frequency of the antenna.

Abstract: In one embodiment, a communication apparatus includes a substrate, an antenna disposed on the substrate, a first communication part transmitting or receiving a signal at a predetermined frequency via the antenna, a first conductor plate, a terminal disposed on the substrate and connected to the first conductor plate by a conductor line, a second communication part disposed on the substrate, connected electrically to the terminal, and communicating with a communication partner via the first conductor plate, and a second conductor plate connected electrically to the conductor line and having a length of substantially ¼ of the wavelength of the predetermined frequency.

Abstract: According to one embodiment, a communication apparatus includes a substrate, a communication circuit, a first signal line, an insulator, and a first conductor. The substrate includes a ground. The communication circuit is provided on the substrate. The first signal line is connected to the communication circuit and is electrically connected to the outer surface of the first conductor. The insulator surrounds the substrate. The first conductor surrounds the insulator.

Abstract: According to one embodiment, the signal electrode is disposed on the first principal surface side of the substrate and is connected to the other end of the second signal line. The housing covers and accommodates therein the substrate, the communication unit, the first signal line, the terminal, the second signal line, and the signal electrode. The conductive material is arranged on an outer side of the housing so as to be opposite to the signal electrode, and includes an outer peripheral portion extended outward beyond an outer periphery of the signal electrode. The communication apparatus carries out data communication via a living body.