Abstract: A disclosed antenna device includes a ground plate, a feeding unit that extends from the ground plate at a predetermined angle for a predetermined length, the feeding unit being prepared perpendicular to the ground plate, and a non-conductive section formed in the ground plate. The shape of the non-conductive section is adjusted according to a desired frequency characteristic.

Abstract: A filtering device is disclosed that can be made compact and has wide-band band-pass characteristics. The filtering device includes a first filtering unit that is composed of a distributed constant circuit and is capable of eliminating a first frequency component or a second frequency component wherein the second frequency being higher than the first frequency, and a second filtering unit that attenuates components of frequencies lower than the first frequency or components of frequencies higher than the second frequency.

Abstract: A small-sized and lightweight pointing device and receiving unit reduce power consumption. The receiving unit transmits UWB (Ultra Wide Band) signals simultaneously from an antenna thereof. The pointing device receives the transmitted UWB signals with three antennas thereof. The respective timings when the transmitted UWB signals are received with the three antennas depend on the distances between the transmitting antenna and the three receiving antennas. With this principle, propagation distances from the transmitting antenna to the three receiving antennas are real distances between the transmitting antenna and the three receiving antennas. By applying the principle of triangular surveying to the distances, position coordinates of the pointing device to the receiving unit can be specified. Amount of movement made by the pointing device is calculated based on a change in the position coordinates.

Abstract: A disclosed antenna device includes a plate-like ground plate, and a feeding unit that extends from the ground plate for a predetermined length at a predetermined angle. The feeding unit is constituted by a half-body, which is a body, such as a circular cone, halved by a plane perpendicular to the ground plate, and the feeding unit is prepared perpendicular to the ground plate.

Abstract: A communication device performs a radio communication in an ultra wideband with the use of the impulse radio system. The communication device includes a receiver. The receiver is equipped with antennas, a correlation circuit, and a CPU. The antennas receive send signals from a transmitter. The correlation circuit detects a synchronization pulse having a longer cycle than a highly redundant data pulse among received signals. The CPU performs a synchronization process based on the synchronization pulse. The CPU establishes a channel based on the synchronization pulse, and selectively changes the antennas according to the received signal. In the case where the receive signal has not been received for a given period of time after the synchronization is established correlation signals is stopped outputting to start a polling signal. The correlation signals are output to obtain-correlation of the receive signals.

Abstract: A non-contact IC card reader/writer device includes antennas that perform carrier wave transmission and reception with a non-contact IC card, an A/D converter that detects the voltage level of each carrier wave received from the non-contact IC card through the antennas, and a control unit that calculates the location of the non-contact IC card from the voltage levels detected by the A/D converter.

Abstract: An acceleration-sensing system for sensing acceleration in a three-dimensional manner is proposed. The acceleration-sensing system includes a first acceleration-sensing unit for sensing acceleration in a two-dimensional manner along first and second directions that are perpendicular to each other and a second acceleration-sensing unit for sensing acceleration in a one-dimensional manner along at least another direction that is perpendicular to the first and second directions.

Abstract: An acceleration detection device for detecting an acceleration applied in a certain direction based on detection signals corresponding to the acceleration, is provided with a waveform detection part detecting waveforms of the detection signals and an acceleration determination part determining whether to make valid or invalid the acceleration based on the waveforms detected in the waveform detection part.

Abstract: An acceleration-sensing system for sensing acceleration in a three-dimensional manner is proposed. The acceleration-sensing system includes a first acceleration-sensing unit for sensing acceleration in a two-dimensional manner along first and second directions that are perpendicular to each other and a second acceleration-sensing unit for sensing acceleration in a one-dimensional manner along at least another direction that is perpendicular to the first and second directions.

Abstract: An acceleration detection device for detecting an acceleration applied in a certain direction based on detection signals corresponding to the acceleration, is provided with a waveform detection part detecting waveforms of the detection signals and an acceleration determination part determining whether to make valid or invalid the acceleration based on the waveforms detected in the waveform detection part.

Abstract: A device includes a coordinate-detecting sheet and a rotating member having a contact part which circularly slides on the coordinate-detecting sheet. Coordinate data of coordinates of the contact part on the coordinate-detecting sheet is output from the coordinate-detecting sheet.

Abstract: A coordinate detection device is provided, which device includes an input unit which has a surface thereof to which a coordinate value is input by an input means, a calculation unit which calculates a difference between previous and current coordinate values input by the input unit, and a setting unit which sets, in the calculation unit, a coordinate value input last before the input means is detached from the surface of said input unit as the previous coordinate value to a coordinate value input first after the input means is detached from the surface of the input unit.