摘要:
A communication method of a coordinator in a bidirectional event transmission sensor network comprising a sensor node and the coordinator is provided. The method includes sensing, in an uplink section, whether a signal having energy greater than or equal to a predetermined magnitude is received, the signal indicating occurrence of an uplink event detected by the sensor node, and transmitting, to the sensor node in a downlink section, a synchronization packet that is used for receiving the uplink event or for transmitting a downlink event in response to the coordinator detecting the downlink event or sensing the signal having energy greater than or equal to the predetermined magnitude in the uplink section. The bidirectional event transmission sensor network has a structure of a super frame that includes at least one standby slot (SS) including the uplink section and the downlink section.
摘要:
A communication method of a coordinator in a bidirectional event transmission sensor network comprising a sensor node and the coordinator is provided. The method includes sensing, in an uplink section, whether a signal having energy greater than or equal to a predetermined magnitude is received, the signal indicating occurrence of an uplink event detected by the sensor node, and transmitting, to the sensor node in a downlink section, a synchronization packet that is used for receiving the uplink event or for transmitting a downlink event in response to the coordinator detecting the downlink event or sensing the signal having energy greater than or equal to the predetermined magnitude in the uplink section. The bidirectional event transmission sensor network has a structure of a super frame that includes at least one standby slot (SS) including the uplink section and the
摘要:
A low power radio device and a radio resource sharing method for the low power radio device are provided. In the low power radio device, a channel state (CS) is detected by carrier sensing before transmission of each frame to reduce interference and a need of retransmission of each frame, accordingly, reducing energy consumption.
摘要:
A low power radio device and a radio resource sharing method for the low power radio device are provided. In the low power radio device, a channel state (CS) is detected by carrier sensing before transmission of each frame to reduce interference and a need of retransmission of each frame, accordingly, reducing energy consumption.
摘要:
A communication device for detecting a collision in an operating frequency band and another frequency band, and a communication method thereof. The communication method includes transmitting or receiving a packet using an operating frequency band. The communication method further includes detecting whether another communication device transmits another packet using another frequency band different from the operating frequency band while the transmitting or the receiving of the packet using the operating frequency band. The communication method further includes ceasing the transmitting or the receiving of the packet using the operating frequency band based on a result of the detection.
摘要:
A cognitive radio-based wireless communication system and an air interface method in a physical layer and a data link layer, which constitute a cognitive radio-based next-generation wireless communication system. The air interface method for wireless communication in the cognitive radio-based wireless communication system of the present invention is provided in the cognitive radio-based wireless communication system including a base station system and a plurality of mobile station systems. The base station system and a certain mobile station system communicate with each other using an overlay method that uses a spectrum hole. The base station system and the mobile station system switch from the overlay method to an underlay method to communicate with each other when a paying user having high priority performs communication using the spectrum hole.
摘要:
Disclosed herein are a method of communicating and establishing a relay channel between a base station and a non-line-of-sight channel terminal in a next generation cellular communication system. The method of communicating between a base station and a non-line-of-sight channel terminal includes a first step of the base station receiving channel state information from the non-line-of-sight channel terminal; a second step of the base station collecting channel state information between the non-line-of-sight channel terminal and adjacent terminals; a third step of, if there is a relay channel terminal that belongs to the adjacent terminals and that can ensure line-of-sight channels to the base station and the non-line-of-sight channel terminal, the base station and the non-line-of-sight channel terminal performing high frequency cellular communication via the relay channel terminal; and a fourth step of, otherwise, the base station and the non-line-of-sight channel terminal performing low frequency cellular communication.
摘要:
The present invention relates to a cognitive radio-based wireless communication system and to an air interface method in a physical layer and a data link layer, which constitute a cognitive radio-based next-generation wireless communication system.The air interface method for wireless communication in the cognitive radio-based wireless communication system of the present invention is provided in the cognitive radio-based wireless communication system including a base station system and a plurality of mobile station systems. The base station system and a certain mobile station system communicate with each other using an overlay method that uses a spectrum hole. The base station system and the mobile station system switch from the overlay method to an underlay method to communicate with each other when a paying user having high priority performs communication using the spectrum hole.