摘要:
An IP packet forwarding server forwards an IP data packet between a user terminal and a machine-type communications (MTC) device allocated with a private internet protocol (IP). Such an IP packet forwarding server allocates a call identifier for connection between the user terminal and the MTC device, sets up a packet call to the MTC device and the user terminal using the call identifier, obtains packet forwarding information while setting up the packet call to the MTC device and the user terminal, and forwards an IP data packet between the MTC device and the user terminal using the packet forwarding information.
摘要:
Provided is a method of managing addresses of incommunicable nodes in a ZigBee network, and more particularly, a method of managing address values of a plurality of nodes that form a ZigBee network by efficiently withdrawing address values from nodes which are incommunicable for reasons of abnormality. An address management process can be performed using two methods. According to a first method, a parent node withdraws address values of child nodes that do not transmit a hello message for a predetermined period of time. According to a second method, a parent node transmits a periodic or non-periodic request message to child nodes, and the child nodes, which receive the request message, immediately transmit a hello message to the parent node. Then, the parent node withdraws address values of child nodes that do not respond to the request message sent by the parent node more than a predetermined number of times. An address value assignment process and a process for nodes that have their address values withdrawn are also provided.
摘要:
A data communication system is provided. The data communication system includes a main processor, and at least one sub-processor or at least one peripheral device connected with the main processor according to a serial peripheral interface (SPI) method and performing an operation corresponding to a command transferred from the main processor. The connection according to the SPI method is made by one or more bus lines including a master in slave out (MISO) line and master out slave in (MOSI) line, a slave select (SS) line, an interrupt line, and a clock transfer line.
摘要:
An RFID tag attached to an object and transmitting a signal that corresponds to identification information includes an RFID tag chip that modulates the signal according to the identification information and an RFID tag antenna that transmits the modulated signal. The RFID tag antenna includes a dielectric material, a radiating patch, and a slit. The dielectric material has a polyhedral shape and includes a first surface that contacts the object and a second surface that is parallel with the first surface, the radiating patch is formed on at least a part of the second surface and radiates electromagnetic to waves, and the slit is formed on at least a part of the radiating patch to expose the dielectric material.
摘要:
An RFID reader controlling device based on a plurality of RFID reader protocols receives control instructions for controlling RFID readers from application devices providing services, and confirms RFID reader protocol types corresponding to control instructions to confirm whether communication channels corresponding to RFID reader protocols are generated. Further, the RFID reader controlling device transmits the control instructions to the RFID readers through the communication channels and transmits the control results of the RFID readers corresponding to the control instructions.
摘要:
A complex communication apparatus transmits/receives voice information with other complex communication apparatuses through a set voice channel. The complex communication apparatus broadcasts a signaling packet expressing a destination identifier representing a desired communication type of one-to-one communication, group communication, and broadcast communication with other complex communication apparatuses and information of the set voice channel and performs voice communication with a complex communication apparatus corresponding to a destination identifier of other complex communication apparatuses, having received the signaling packet.
摘要:
A slot managing method and apparatus is provided. A first layer of a destination node receives a request command for requesting a slot management from a source node, and transfers a first primitive for reporting a receipt of the request command to a second layer that is an upper layer of the first layer. The second layer transfers a second primitive to the first layer as a response to the slot management request. The first layer broadcasts a reply command including a result of the slot management request to neighboring nodes in response to the second primitive. The source node broadcasts a notify command including a result of the slot management request.
摘要:
To track the location of a terminal in an indoor space by using a pseudo GPS signal transmitter, a GPS signal sent from an artificial satellite is received, and a clock signal of the artificial satellite is extracted from the received GPS signal to perform synchronization with the artificial satellite. Once synchronization with the artificial satellite is performed, a pseudo GPS signal is generated, and the transmission time of the pseudo GPS signal is controlled. The GPS signal is sent to the terminal located in the indoor space by a plurality of transmitting antennas based on the controlled transmission time, thereby enabling the terminal located in the indoor space to track its location.
摘要:
A constant amplitude decoding apparatus and method for multiplexed direct-sequence spread spectrum communication system are provided. The constant amplitude decoding apparatus includes: a despreading and demultiplexing module receiving a data stream of a constant amplitude and despreading and demultiplexing the received data stream to restore it to a 2D signal; a decoding module first performing a vertical decoding on the 2D signal and then performing horizontal decoding thereon; a control module determining whether to repeatedly perform vertical decoding and horizontal decoding; and a bit stream information output module outputting the decoding results from the decoding module as a bit stream.
摘要:
Provided are an energy-efficient communication method in a group information-based sensor network and a sensor network system using the method. A group exchanges group information and data with another group in order to provide an application service through inter-group cooperation in a sensor network. In this process, a target group is discovered, a communication path is established, and inter-group communication cycle information for energy-efficient communication is transmitted. On the basis of the group information and the communication cycle information, it is possible to minimize the network resource consumption and provide an energy-efficient inter-group communication method.