Abstract: There is provided a communication device including (1) a communication controller that causes a control frame for synchronization to be transmitted during a control frame transmission period to a transmission destination of a data frame such that the data frame is transmitted after transmission of the control frame has completed, (2) a transmission section that continuously transmits the control frame for the control frame transmission period, (3) a reception section that receives a frame transmitted by a communication device of the transmission destination, (4) a control frame transmission information saving section that saves information for respective destination addresses, (5) a control frame transmission controller that references the information saved in the control frame transmission information saving section, and determines the control frame transmission period for when to transmit the next control frame, based on the control frame transmission period from the past and the data frame transition resul

Abstract: There is provided a wireless transmission device in which a lower layer processing unit inserts first random delay before frame transmission in response to a frame transmission request made by an upper layer processing unit, the wireless transmission device including a frame transmitting unit configured to transmit a frame when the frame transmission request is made by the upper layer processing unit, and a frame group transmitting unit configured to transmit a frame group including one or two or more types of frame in accordance with a listening state of a facing wireless reception device when the frame transmission request is made by the upper layer processing unit.

Abstract: The present disclosure provides a communication device, including: a reception section that receives information relating to a reception timing at a reception side, which is transmitted from a transmission destination after a data frame is transmitted to the transmission destination; an information storage section that stores a transmission interval and the information relating to the reception timing for previous transmissions; a mismatch correction section that, in a case in which a new data frame is transmitted, calculates a correction amount for eliminating a mismatch in a transmission timing of a wakeup frame or a mismatch in a reception timing at which the transmission destination receives the wakeup frame, based on the transmission interval and the information relating to the reception timing; and a communication control section that determines the transmission or reception timing based on the information relating to the reception timing and the correction amount.

Abstract: There is provided a communication device including (1) a communication controller that causes a control frame for synchronization to be transmitted during a control frame transmission period to a transmission destination of a data frame such that the data frame is transmitted after transmission of the control frame has completed, (2) a transmission section that continuously transmits the control frame for the control frame transmission period, (3) a reception section that receives a frame transmitted by a communication device of the transmission destination, (4) a control frame transmission information saving section that saves information for respective destination addresses, (5) a control frame transmission controller that references the information saved in the control frame transmission information saving section, and determines the control frame transmission period for when to transmit the next control frame, based on the control frame transmission period from the past and the data frame transition resul

Abstract: The present disclosure provides a communication device, including: a reception section that receives information relating to a reception timing at a reception side, which is transmitted from a transmission destination after a data frame is transmitted to the transmission destination; an information storage section that stores a transmission interval and the information relating to the reception timing for previous transmissions; a mismatch correction section that, in a case in which a new data frame is transmitted, calculates a correction amount for eliminating a mismatch in a transmission timing of a wakeup frame or a mismatch in a reception timing at which the transmission destination receives the wakeup frame, based on the transmission interval and the information relating to the reception timing; and a communication control section that determines the transmission or reception timing based on the information relating to the reception timing and the correction amount.

Abstract: A context-awareness system has an event data producer for forming event data from node data including a node value and node information, a context producer, and an event data manager for storing event data formation suppression information and event data conversion rules. The context producer sends the number of entries of event data (the number of inputs) to the event data manager per unit time. The manager sends to the event data producer the event data formation suppression information and event data conversion rules corresponding to the number of inputs. The event data producer forms event data depending on the event data formation suppression information and event data conversion rules corresponding to the number of inputs. Appropriate context information is formed without increasing the amount of resources when data including values related to events are entered in large amount and frequently.

Abstract: There is provided a wireless transmission device in which a lower layer processing unit inserts first random delay before frame transmission in response to a frame transmission request made by an upper layer processing unit, the wireless transmission device including a frame transmitting unit configured to transmit a frame when the frame transmission request is made by the upper layer processing unit, and a frame group transmitting unit configured to transmit a frame group including one or two or more types of frame in accordance with a listening state of a facing wireless reception device when the frame transmission request is made by the upper layer processing unit.

Abstract: A context-awareness system has an event data producer for forming event data from node data including a node value and node information, a context producer, and an event data manager for storing event data formation suppression information and event data conversion rules. The context producer sends the number of entries of event data (the number of inputs) to the event data manager per unit time. The manager sends to the event data producer the event data formation suppression information and event data conversion rules corresponding to the number of inputs. The event data producer forms event data depending on the event data formation suppression information and event data conversion rules corresponding to the number of inputs. Appropriate context information is formed without increasing the amount of resources when data including values related to events are entered in large amount and frequently.

Abstract: A method and a system for providing presence information is disclosed which can incorporate non-presence-ready terminal nodes such as sensor node terminals and combine a plurality of pieces of presence information from a plurality of nodes, thereby providing presence information with improved reliability. The method includes creating circumstance presence information associated with a user in response to a change in value of sensor data transmitted from at least one sensor node terminal. For a presence server to deliver presence information, the method also includes delivering circumstance presence information created in relation to the user either in place of the presence information or in combination with the presence information.

Abstract: A gateway apparatus relays a data packet only when a network that is connected to the gateway apparatus itself is identical to a network that is connected to a node associated with a sender's address. The sender's address is carried in the data packet received. Even if there are accesses from a plurality of nodes to a certain node (e.g., sensor node), the gateway apparatus can relay the data packet such that data retrieval takes place appropriately and/or such that node control takes place appropriately.

Abstract: A method and a system for providing presence information is disclosed which can incorporate non-presence-ready terminal nodes such as sensor node terminals and combine a plurality of pieces of presence information from a plurality of nodes, thereby providing presence information with improved reliability. The method includes creating circumstance presence information associated with a user in response to a change in value of sensor data transmitted from at least one sensor node terminal. For a presence server to deliver presence information, the method also includes delivering circumstance presence information created in relation to the user either in place of the presence information or in combination with the presence information.

Abstract: A transmission timing control apparatus included in a network node constituting a telecommunications system is configured to use the reception timing of a timing signal from another node to determine the transmission timing of a timing signal of the own node and determine a time slot for transmission of a data signal in accordance with the transmission timing and the reception timing of a timing signal from the other node. A response timing signal transmitter transmits a response timing signal when received the timing signal from the other node. A transmission timing control circuit uses the reception timing of the timing signal and that of the response timing signal to determine the timing at which the own node transmits the timing signal.

Abstract: In a transmission timing control apparatus, a state variable signal affected by a phase representing the data transmission timing of a neighboring node is used to determine the data transmission timing of the own node. A node information transmitter/receiver transmits source identification information particular to the own node and source node information of a data signal received by the own node, and receives node information transmitted from the neighboring node. A neighboring node information collecting circuit collects neighboring node information of all neighboring nodes having received data signals, based upon the source identification information received by the node transmitter/receiver and the source node information.

Abstract: A communication control apparatus is included in each of nodes constituting a telecommunications system and includes a communication timing signal transmitter/receiver for receiving a communication timing signal representative of a transmission timing of a data signal from at least one neighboring node neighboring the own node, and transmitting the communication timing signal of the own node. In the apparatus, a communication timing determining circuit determines a transmission timing of the communication timing signal of the own node in accordance with basic rate information, which defines a transmission timing of the communication timing signal of the own node, and the communication timing signal received from the neighboring node. A basic rate information control circuit included in the apparatus controls the basic rate information used by the communication timing determining circuit.

Abstract: A gateway apparatus relays a data packet only when a network that is connected to the gateway apparatus itself is identical to a network that is connected to a node associated with a sender's address. The sender's address is carried in the data packet received. Even if there are accesses from a plurality of nodes to a certain node (e.g., sensor node), the gateway apparatus can relay the data packet such that data retrieval takes place appropriately and/or such that node control takes place appropriately.

Abstract: Each node in a communication system transmits and receives state variable signals indicating internal node states or timings, generates transitions in its internal state or timing at a basic rate but at timings adjusted according to the received state variable signals, transmits data in time slots synchronized to the output state variable signals, receives data signals from the other nodes, detects collisions between the received data signals, and changes the timing of its time slots when a collision is detected, by shifting the phase of the transitions, or by inserting additional dummy transitions and transmitting corresponding dummy output state variable signals. The nodes can thereby assign their own time slots and avoid collisions autonomously.

Abstract: A communication timing control apparatus for use in the nodes of a communication system includes a signal communication unit that transmits a state variable signal to neighboring nodes and receives state variable signals from those nodes. An external control signal, such as a beacon signal transmitted by a control node, is also received. The state variable signals indicate internal operating states or timings of the nodes; the control signal indicates a basic transition rate. A timing decision unit causes internal state or timing transitions to occur at timings responsive to the basic transition rate and the received state variable signals, adjusting the transition timings so as to avoid signal collisions and to adapt to changing system conditions, Use of the control signal enables a steady timing state to be reached quickly.

Abstract: Each node on a communication path receives state variable signals from other nodes indicating the internal operating states or internal timing of the other nodes, and transmits a state variable signal indicating its own internal operating state or timing. Transitions in the internal operating state or timing of a node take place at a basic transition rate but at times adjusted according to the state variable signals received from other nodes. The basic transition rate varies according to position on the communication path. The nodes can thereby establish transmitting time slots that follow each other in progression on the communication path, enabling data signals to be relayed from the starting node to the destination node with minimal delay at each intermediate node.

Abstract: Each node in a communication system transmits and receives state variable signals indicating internal node states or timings. A single node may transmit two or more differently phased series of state variable signals. Neighboring nodes interact by adjusting the timing phase at which they transmit each series of state variable signals according to the timing of state variable signals transmitted in other series, and state variable signals received from other nodes. The nodes can thereby establish time slots in which they can transmit data without collisions, and different nodes can receive different total amounts of time slot width by transmitting different numbers of series of state variable signals.

Abstract: A communication control apparatus is included in each of nodes constituting a telecommunications system and includes a communication timing signal transmitter/receiver for receiving a communication timing signal representative of a transmission timing of a data signal from at least one neighboring node neighboring the own node, and transmitting the communication timing signal of the own node. In the apparatus, a communication timing determining circuit determines a transmission timing of the communication timing signal of the own node in accordance with basic rate information, which defines a transmission timing of the communication timing signal of the own node, and the communication timing signal received from the neighboring node. A basic rate information control circuit included in the apparatus controls the basic rate information used by the communication timing determining circuit.