Abstract:
Disclosed is technology capable of performing a communication using an ultrasonic wave in an environment with the difficulty of a wireless communication using an electromagnetic wave due to electromagnetic wave shield. An ultrasonic terminal according to the present invention transmits the ultrasonic wave by a solid structure as a medium in the environment with the electromagnetic wave shield and an ultrasonic base station receives the ultrasonic wave by the solid structure as the medium.
Abstract:
PURPOSE: A spatial multiplexing communication system is provided to transmit data by using a communication channel without interference. CONSTITUTION: A transmission device estimates distance between a receiving device and oneself (410). The transmission device selects a part of a plurality of activated transmission antennas. The transmission device inactivates the selected transmission antennas. The transmission device groups the plurality of activated transmission antennas into a plurality of groups (420). The transmission device transmits data to the receiving device by performing beam-forming as to each group. [Reference numerals] (410) Estimate distance; (420) Grouping antennas; (430) Transmit group information; (440) Receive channel rank; (450) Determine transmit beam; (460) Transmit data; (AA) Start; (BB) End
Abstract:
PURPOSE: A disaster prevention system and a method thereof based on a wireless local access network are provided to bilaterally correspond to the disasters. CONSTITUTION: A disaster prevention center (220) corresponds to the disaster information related to a disaster state which is sensed by a user terminal (210). A network (230) exchanges messages between the user terminal and the disaster prevention center. The disaster prevention center includes a disaster report processing unit (221) and a disaster information managing unit. The disaster report processing unit processes the disaster information. The disaster information managing unit generates the disaster corresponding information based on the processed disaster information and transmits the disaster broadcasting information including the disaster corresponding information to the user terminal. [Reference numerals] (211) User interface control unit; (212) Disaster report processing unit; (213) Disaster application managing unit; (214) Disaster broadcasting reception unit; (215) Disaster information processing unit; (216) RF unit; (221) Disaster report processing unit; (222) Disaster situation processing unit; (223) Disaster information managing unit; (224) Evacuating information managing unit; (225) Authorization Key managing unit; (226) Disaster prevention database; (230) Network; (231) Core network
Abstract:
PURPOSE: A public service providing system is provided to enable a user to conveniently receive public services through a user terminal by providing the integrated public service to the user terminal. CONSTITUTION: A service management unit(110) provides public services for a local server(200) which provides the public services by receiving a public service providing registration or dissipation request form each service provider servers(300). A user management unit(120) registers or dissipates the public services for the user of the user terminal by receiving the public service registration or dissipation request from the user terminal. The user management unit stores public service registration information by matching public service identification information with user identification information.
Abstract:
PURPOSE: A contention based channel access method using a directional antenna in a broadband wireless communication system and a device thereof are provided to reduce the number of attempts for impossible communication. CONSTITUTION: An information collecting unit(610) receives contention section participation intention information and receiving antenna setup information from distribution devices in a network. A resource allocation scheduling unit(620) allocates resources. The resource allocation scheduling unit is divided into a beam forming available contention section and a beam forming unavailable contention section. A beacon generating unit(630) generates a beacon message including information about the beam forming available contention section and the beam forming unavailable contention section.