Abstract: A communication system includes the following elements: a transmitter including a transmission circuit unit configured to generate an RF signal for transmitting data and an electric-field-coupling antenna configured to transmit the RF signal as an electrostatic field; a receiver including an electric-field-coupling antenna and a reception circuit unit configured to receive and process the RF signal received by the electric-field-coupling antenna; and a surface-wave propagation medium configured to provide a surface-wave transmission line to transmit a surface wave emanating from the electric-field-coupling antenna of the transmitter with low propagation loss.

Abstract: A communication system includes: a transmitter including a transmission circuit unit generating an RF signal for transmitting data and an electrical-field coupling antenna transmitting the RF signal as an electrostatic field or an induction field; a receiver including an electrical-field coupling antenna and a reception circuit unit subjecting an RF signal received by the electrical-field coupling antenna to reception processing; and a surface-wave propagation device including a plurality of linear surface-wave transmission lines for propagating a surface wave radiated from the electrical-field coupling antenna of the transmitter.

Abstract: A communication system, including a transmitter having a transmitting circuit unit to generate a data transmission-adaptive RF signal and an electric-field-coupling antenna to send out the RF signal as an induction field and/or an electrostatic field, a receiver having a electric-field-coupling antenna and a receiving circuit unit to receive and process the RF signal received by the electric-field-coupling antenna, and a coupling apparatus having a plurality of transmitter-side electric-field-coupling antennas to receive the RF signal which is in capacitive coupling with the transmitter-side electric-field-coupling antenna and outputted from the electric-field-coupling antenna, a signal line to transmit the received RF signal, and a plurality of receiver-side electric-field-coupling antennas to output the RF signal which is in capacitive coupling with said the receiver-side electric-field-coupling antenna and transmitted through the signal line.

Abstract: A communication system includes the following elements: a transmitter including a transmission circuit unit configured to generate an RF signal for transmitting data and an EFC antenna configured to transmit the RF signal as an electrostatic field or an induced electric field; and a receiver including an EFC antenna and a reception circuit unit configured to receive and process the RF signal received by the EFC antenna. The EFC antennas of the transmitter and the receiver each include a coupling electrode and a resonating section including a distributed-constant circuit configured to strengthen electrical coupling between the coupling electrodes. The RF signal is transmitted by electric-field coupling between the EFC antennas, facing each other, of the transmitter and the receiver.

Abstract: A communication system includes the following elements: a transmitter including a transmission circuit unit configured to generate an RF signal for transmitting data and an EFC antenna configured to transmit the RF signal as an electrostatic field or an induced electric field; a receiver including an EFC antenna and a reception circuit unit configured to receive and process the RF signal received by the EFC antenna; and an impedance snatching unit configured to make an impedance of the EFC antenna of the transmitter equal to an impedance of the EFC antenna of the receiver. The RF signal is transmitted by electric-field coupling between the EFC antennas, facing each other, of the transmitter and the receiver.

Abstract: A communication system includes a transmitter including a transmission circuit unit that generates an RF signal for transmitting data and an electric-field-coupling antenna that transmits the RF signal as an electrostatic field, a receiver including an electric-field-coupling antenna and a reception circuit unit that subjects an RF signal received by the electric-field-coupling antenna to reception processing, and a surface-wave propagating means for providing a surface wave transmission line made of a conductor that propagates a surface wave radiated from the electric-field-coupling antenna of the transmitter along a surface of the surface wave transmission line.

Abstract: In a reverse F-shaped antenna formed on a surface of a printed board, the radiating element has a first radiating conductor, a second radiating conductor, and a chip coil. The chip coil is positioned between the first and second radiating conductors and electrically connects the first radiating conductor to the second radiating conductor. The reverse F-shaped antenna is effectively downsized. A component of current flow in the chip coil in a three-dimensional direction allows sensitivity to some extent to a wave polarized in all directions. By merely changing the inductance in the chip coil, it is possible to easily alter the resonance frequency in the reverse F-shaped antenna.

Abstract: An antenna achieves effective diversity reception in even a small sized wireless signal-receiving apparatus, improvement in the sensitivity of the antenna, and implementation of a small size, a lower power consumption, and a low price of the antenna. The antenna has antenna elements that are positioned at a smaller distance apart than a half wavelength of the frequency of a signal to be received, a first transmission line and a second transmission line having a delay circuit with a predetermined electric length, and a changeover switch 13. The difference of the electric length of a path that passes from one antenna element through one of the transmission lines toward a synthesizer from the electric length of a path that passes from the other antenna element through the other transmission line toward the synthesizer is set so as to become (?/2??) or (??/2+?). When receiving a signal, the changeover switch changes based on a control signal, so that the directivity of the antenna can vary.

Abstract: A flat cable includes a signal line extending in a longitudinal direction, a thin dielectric sheet with which the signal line is coated and that has plasticity, a pair of spaced apart ground layers extending in the longitudinal direction and sandwiching the dielectric sheet in its thickness direction, and insulators that coat the pair of ground layers so that they are not exposed to the outside. The cross-sectional size of the signal line in a direction orthogonal to the longitudinal direction, the thickness and width of the dielectric sheet, and so forth are selected to obtain a predetermined characteristic impedance for the cable. Each of the pair of ground layers is sized so as to be substantially wider than the signal line.

Abstract: A wireless communication system has a transmitter and a receiver. The transmitter includes a transmission-data-processing device that generates items of data for a first series and items of data for a second series, a transmission-processing device that generates transmission signals for each series based on these items of data, and a wireless-signal-transmitting device that transmits the transmission signals generated by the items of data for the first series and the items of data for the second series as wireless signals of an anti-clockwise polarized scheme and of a clockwise polarized scheme, respectively.

Abstract: A distributing apparatus distributes a high-frequency signal received from a transmitting-and-receiving module of a first wireless terminal to transmitting-and-receiving modules of other wireless terminals with a wiring scheme. The apparatus has at least three signal transmission lines each transmitting the high-frequency signal. It also has a connecting node that connects an end of each of the signal transmission lines to each other, and an attenuator on each of the signal transmission lines and positioned near the connecting node, the attenuator on each signal transmission line attenuating the high-frequency signal on that signal transmission line. An input or output terminal of each of the transmitting-and-receiving modules of the wireless terminals is connected to any one of the signal transmission lines with a wiring scheme. One of the transmitting-and-receiving modules then transmits a communication signal.

Abstract: A flat cable includes a signal line extending in a longitudinal direction, a thin dielectric sheet with which the signal line is coated and that has plasticity, a pair of spaced apart ground layers extending in the longitudinal direction and sandwiching the dielectric sheet in its thickness direction, and insulators that coat the pair of ground layers so that they are not exposed to the outside. The cross-sectional size of the signal line in a direction orthogonal to the longitudinal direction, the thickness and width of the dielectric sheet, and so forth are selected to obtain a predetermined characteristic impedance for the cable. Each of the pair of ground layers is sized so as to be substantially wider than the signal line.

Abstract: In a reverse F-shaped antenna formed on a surface of a printed board, the radiating element has a first radiating conductor, a second radiating conductor, and a chip coil. The chip coil is positioned between the first and second radiating conductors and electrically connects the first radiating conductor to the second radiating conductor. The reverse F-shaped antenna is effectively downsized. A component of current flow in the chip coil in a three-dimensional direction allows sensitivity to some extent to a wave polarized in all directions. By merely changing the inductance in the chip coil, it is possible to easily alter the resonance frequency in the reverse F-shaped antenna.

Abstract: A line-shaped comprises an antenna element in which a strip-shaped conductor is bent in a width direction of a strip, and a chamfered portion is provided on an outer edge of a bent portion of the strip-shaped conductor.

Abstract: A small antenna comprises a first meander part formed in such a manner that a meander conductor travels to a first direction and having a first end and a second end, and a second meander part formed in such a manner that a meander conductor travels to a second direction different from the first direction and having a first end connected with the second end of the first meander part and a second end.

Abstract: A compact antenna comprises a core which is a hard linear member having a predetermined shape corresponding to resonance characteristic, a conductor film which covers at least a portion of an outer surface of the core and which has higher electric conductivity than that of the core, and a substrate which closely surrounds and holds the outer surface of the core covered with the connection film. A film thickness of the conductor film is equal to a skin depth and thus, it is possible to inexpensively maintain reliability, and to prevent radiation efficiency from being lowered.

Abstract: A line-shaped comprises an antenna element in which a strip-shaped conductor is bent in a width direction of a strip, and a chamfered portion is provided on an outer edge of a bent portion of the strip-shaped conductor.

Abstract: A compact antenna comprises a core which is a hard linear member having a predetermined shape corresponding to resonance characteristic, a conductor film which covers at least a portion of an outer surface of the core and which has higher electric conductivity than that of the core, and a substrate which closely surrounds and holds the outer surface of the core covered with the connection film. A film thickness of the conductor film is equal to a skin depth and thus, it is possible to inexpensively maintain reliability, and to prevent radiation efficiency from being lowered.

Abstract: A small antenna comprises a first meander part formed in such a manner that a meander conductor travels to a first direction and having a first end and a second end, and a second meander part formed in such a manner that a meander conductor travels to a second direction different from the first direction and having a first end connected with the second end of the first meander part and a second end.