Abstract: There is disclosed a wireless communication apparatus that does not interrupt synchronous communication but can continuously perform the synchronous communication even when an address duplication occurs between the local wireless communication apparatus and a nearby wireless communication apparatus. A plurality of wireless communication apparatuses constitutes an ad hoc network system where they transmit beacons to each other. In the wireless communication apparatus, an address processing part (145) generates a first address, which includes a beacon period slot number corresponding to the position-on-beacon-period of a beacon generated by the local wireless communication apparatus, and a second address assigned at random. A beacon processing part (140) determines whether the second address generated by the address processing part (145) is coincident with a second address at another wireless communication apparatus.

Abstract: A distributed wireless medium access control protocol is disclosed. According to the disclosed wireless medium access control protocol the medium access time is partitioned into equal sized slots, and a predetermined number of the slots forming a superframe. The protocol defines beaconing devices and passive devices. Each beaconing device designates one of the slots in the superframe as its beacon medium access slot, and broadcasts during that beacon medium access slot a beacon frame to other devices in wireless range of that beaconing device. A beacon frame collision detection and resolution procedure, and a procedure for reserving access time for communication between devices are also disclosed.

Abstract: Provided is a wireless communication apparatus wherein random multi-access can be performed while ensuring a transmission distance, even with a radio wave having directivity. A wireless communication apparatus (100) transmits/receives directional radio waves and performs ad hoc network communication with other wireless communication apparatuses. The wireless communication apparatus is provided with an antenna (110) for transmitting/receiving the directional radio waves and switching the directivity, and a control section (132) for controlling timing for switching the directivity of the antenna.

Abstract: A radio communication device includes a communication data selection unit for selecting from the received radio communication data containing communication time reservation request information in which a time slot for performing data transmission source radio communication device is described and a communication information analysis unit for extracting an identifier of the source radio communication device and the data transmission reservation time slot from the communication time reservation request information in the radio communication data. When the received radio communication data is addressed to the local device, a communication/response information generation unit correlates the identifier to the reservation time slot, records them in a communication reservation table, and generates communication time reservation response information including information of the reservation time slot.

Abstract: Provided is a radio communication method capable of optimally using the wide-band communication enabled time while maintaining power saving in an ad hoc network. According to this method, in the ad hoc network using the wide-band communication and a narrow-band communication, transmission and output of the narrow-band synchronization tone signal and the resynchronization tone signal are controlled so that the reach radius of the narrow-band synchronization signal and the resynchronization tone signal exceeds the reach radius of the wide-band signal (milli-wave UWE signal). Thus, when radio communication devices pass by each other, super frame synchronization is completed before reaching the wide-band communication enabled range of the ad hoc network, thereby optimally using the wide-band communication-enabled time.

Abstract: A beacon slot position control section of a radio communication apparatus constituting a radio network system which detects whether empty beacon slots are present in a beacon period. When an empty beacon slot is present before the period in which the radio communication apparatus transmits a beacon, a movable counter starts counting a specified number of super frames. When the count is completed, the radio communication apparatus transmits a beacon of the radio communication apparatus at the earlier empty beacon slot. Consequently, since the empty beacon slots are eliminated and the beacon period is compacted, even if the number of radio communication apparatuses joining the radio network system fluctuates dynamically, the radio communication apparatus can perform radio communication with high efficiency and less waste of consumed electricity.

Abstract: A beacon slot position control section of a radio communication apparatus constituting a radio network system which detects whether empty beacon slots are present in a beacon period. When an empty beacon slot is present before the period in which the radio communication apparatus transmits a beacon, a movable counter starts counting a specified number of super frames. When the count is completed, the radio communication apparatus transmits a beacon of the radio communication apparatus at the earlier empty beacon slot. Consequently, since the empty beacon slots are eliminated and the beacon period is compacted, even if the number of radio communication apparatuses joining the radio network system fluctuates dynamically, the radio communication apparatus can perform radio communication with high efficiency and less waste of consumed electricity.

Abstract: A heating apparatus including a filament arranged in a vacuum heating vessel comprises a base plate arranged in the vacuum heating vessel to fix the filament at a predetermined position with respect to a conductive heater forming one surface of the vacuum heating vessel. The base plate comprises a plate body having a carbon fiber.

Abstract: A substrate heating apparatus having a conductive heater which heats a substrate includes a filament arranged in the conductive heater and connected to a filament power supply to generate thermoelectrons, and an acceleration power supply which accelerates the thermoelectrons between the filament and conductive heater. The filament has inner peripheral portions formed at a predetermined interval along an inner circle concentric with the substrate, outer peripheral portions formed at a predetermined interval on an outer circle concentric with the inner circle and having a diameter larger than that of the inner circle, and a region formed by connecting the end point of each inner peripheral portions and the end point of a corresponding one of the outer peripheral portions.

Abstract: A beacon slot position control section (205) of a radio communication apparatus constituting a radio network system which detects whether empty beacon slots are present in a beacon period. When an empty beacon slot is present before the period in which the radio communication apparatus transmits a beacon, a movable counter (206) starts counting a specified number of super frames. When the count is completed, the radio communication apparatus transmits a beacon of the radio communication apparatus at the earlier empty beacon slot. Consequently, since the empty beacon slots are eliminated and the beacon period is compacted, even if the number of radio communication apparatuses joining the radio network system fluctuates dynamically, the radio communication apparatus can perform radio communication with high efficiency and less waste of consumed electricity.

Abstract: A method and device for wireless directional beam-forming transmission. The method for wireless directional beam-forming transmission between a first device and a second device comprises conducting one or more omni-directional transmissions between the first device and a third device; conducting one or more omni-directional transmissions between the second device and the third device; and determining directional information for directional beam forming transmissions between the first and second devices based on the omni-directional transmissions.

Abstract: A frame such as a beacon in wireless communication, with a maximum MAC address, hop count, and maximum hop count, described therein is exchanged between nodes. All the nodes measure the number of hops from a node with the maximum MAC address, and exchange the maximum hop count (hmax) out of the numbers with each other. Hop count H(a,b) between arbitrary nodes a and b is expressed by H(a,b)?H(a,max)+H(max,b)?2*hmax, where hmax is a hop count from node (max) with the maximum MAC address to the farthest node. That is, the number of hops between two arbitrary nodes in the group is always 2*hmax or less. Herewith, a numeric value assuredly exceeding the maximum value out of the numbers of hops between nodes in an ad-hoc network can be propagated in the entire ad-hoc network.

Abstract: A method and system for wireless communication between devices over the same channel in a Wireless Personal Area Networks (WPANs) environment, and a device capable of wireless communication with other devices over the same channel in a WPANs environment. The method comprises the steps of broadcasting announcements from one or more WPAN control devices; providing in each announcement an announcement portion for announcing information about one or more WPAN control devices other than said respective announcing WPAN control device; and partitioning medium access time for the communication between the devices over the same channel based on the announcements.

Abstract: A network communication system is provided whereby communication stations can obtain priority for data transmission to communicate directly with each other in a contention-free mode communication period independently of a polling operation of the control station. The control station emits a series of beacons at equal intervals to initiate contention-free mode communication at the completion of a predetermined number of beacons. During the maximum contention-free mode communication period a contention-free communication operation is initiated, for allowing contention-free mode transmission, by a polling operation by the control station. A series of time-slots is imaginarily provided at equal intervals from the start of the contention-free period throughout the maximum contention-free period. A communication station conducts a call-connection procedure in order to obtain a priority for data transmission in a given set of time-slots.

Abstract: A radio communication device includes a beacon reception unit extracting a frame from a received beacon and a frame judgment unit judging whether the extracted frame is one requiring data transmission/reception or one giving notice of a collision with a beacon of another network, a frame constructing unit used when the frame judgment unit has judged that the frame is a collision notification, generating a frame for relaying the collision notification and a movement notification to a new beacon transmission period, and a beacon transmission instruction unit instructing transmission of the frame at the beacon transmission timing. Accordingly, since these notifications can be relayed, all radio communication devices of the same network can move to a new beacon transmission period while avoiding a collision with a beacon from a radio communication device of another network.

Abstract: In the case where a screen divided display is performed on a liquid crystal panel, a change in brightness or chromaticity between sub regions divided may be reduced. A display includes: a display panel; a backlight arranged corresponding to each of sub regions, and selectively illuminating the corresponding sub region, the sub regions being defined by dividing a display region of the display panel into a plurality of parts; a monitoring means for monitoring the light emission state of the backlight corresponding to each of the sub regions; and a display control means for determining a sub region on which an image is to be displayed, on the basis of the monitoring result of the monitoring means, to fit the image into the determined sub region, and controlling a backlight corresponding to the determined sub region to emit light.

Abstract: A first receiving unit typically receives a control frame in a narrowband channel. A communication data selection unit controls power saving of a second receiving unit performing reception in a UWB channel, based on the control frame. A communication data generation unit generates communication time reservation response information by adding information reporting a normal reception to the received request for communication time reservation, and transmits this information from transmitting units in the narrowband channel, so that a second receiving unit is set to an operating mode only during a time slot when UWB communication is performed, and use of the time slot for performing UWB communication is reported to the radio communication device which has made the communication request and the radio communication devices in the area where transmission is possible.

Abstract: An information processing apparatus, which includes: a device search section that searches a device connected through a communication section; a radio field intensity acquisition section that acquires from the device searched by the device search section a radio field intensity of the device for wireless communication with the communication section; a device selection section that selects a device in accordance with the radio field intensity acquired by the radio field intensity acquisition section; a device control program acquisition section that acquires a device control program for the device selected by the device selection section; and a device control program setting section that sets the device control program acquired by the device control program acquisition section so as to be available.

Abstract: A wireless communication device comprises a wireless communication unit that performs wireless communication; a connector that enables exchange of a signal with an information processing device; an acquisition unit that acquires setting information when an information processing device connected to the connector uses the wireless communication unit based on the setting information stored in the information processing device; a storing unit that stores the setting information acquired by the acquisition unit; and a communication processing unit that performs communication processing by using the wireless communication unit based on the setting information stored by the storing unit.

Abstract: A wireless communication system comprises a base station, and a wireless communication apparatus performing wireless communications with the base station, wherein the wireless communication apparatus comprises a communication unit that performs wireless communications with the base station and wireless communications between apparatuses without involving the base station; a storage unit that stores setting information used by the communication unit for wireless communications with the base station; a detector that detects whether of not there is a communicable object apparatus in a range where the communication unit is able to perform wireless communications between apparatuses; and a transmitter that transmits the setting information stored in the storage unit to the object apparatus detected by the detector via the communication unit.