摘要:
Provided are a method of adjusting a PCS threshold in a wireless network, and a terminal apparatus for the wireless network. The method and the apparatus determines whether to adjust the PCS threshold to use a shared channel for transmitting data in a wireless network based on a congestion status of the shared channel, and adjusts the PCS threshold based on a packet loss measured for a predetermined period of time.
摘要:
A method of recognizing a tag in an RFID reader includes: obtaining a predetermined frame size in the case where throughput obtained by reflecting a slot length based on the remaining number of tags except for recognized tags within a frame progressing current tag recognition that substantially has a maximum value; and when the current frame size is different from the predetermined frame size, stopping the current progress of frame and changing the current frame size into the expected frame size. The method of recognizing a tag may further include when the current frame size is equal to the expected frame size, changing the current frame size into the frame size that does not cause a throughput inversion phenomenon for the remaining number of tags to be recognized within the frame progressing the current tag recognition. By the throughput inversion phenomenon, the occurrence of throughput loss can be prevented and the tag recognition time is reduced to recognize the tags at high speed.
摘要:
Disclosed is a navigation apparatus and method using RFID that is capable of providing information on a current position and a moving direction to the destination. An antenna unit has directivity in a predetermined direction and receives at least one radio signal transmitted from at least one RFID tag. An RFID reader converts the at least one radio signal provided by the antenna unit into information on the at least one RFID tag in a digital form, measures the reception strength of the at least one radio signal, and provides the information on the at least one RFID tag and information on the received strength. A control unit determines the current position and moving direction on the basis of the information on the at least one RFID tag and the information on the reception strength provided from the RFID reader. Accordingly, it is possible to accurately recognize the current position and the moving direction of the navigation apparatus and guide the moving direction to the destination.
摘要:
Provided are a packet transmission scheduling method in a wireless network and a packet transmission method using the same. The packet transmission scheduling method, includes storing location information and a path loss exponent of each node on a multiplexing path; calculating a Signal-to-Interference and Noise Ratio (SINR) between nodes on a predetermined path based on the stored location information; when the calculated SINR exceeds a threshold, forming the paths as a path table; and scheduling packet transmission based on the formed path table.
摘要:
Provided is a cross-layer routing method in a wireless sensor network including: locating a destination node which is a final destination of data by a source node which generates the data; and determining an optimal relay node among one or more neighboring nodes using their position information for each hop and forwarding the data from the source node to the destination node through the determined relay nodes. Therefore, an effective and stable routing which reduces overheads of additional control messages used for stable data forwarding and reduces collisions in a shared channel by using wireless link layer characteristics can be implemented.
摘要:
Provided are a method of adjusting a PCS threshold in a wireless network, and a terminal apparatus for the wireless network. The method and the apparatus determines whether to adjust the PCS threshold to use a shared channel for transmitting data in a wireless network based on a congestion status of the shared channel, and adjusts the PCS threshold based on a packet loss measured for a predetermined period of time.
摘要:
A security system using a laser range finder that can precisely determine an existence and a location of an intruder, and a method of detecting the intruder using the laser range finder are provided. The security system using a laser range finder, the security system includes: the laser range finder emitting laser beam, receiving the reflected laser beam, measuring a distance between the laser range finder and a target object, and detecting an existence and a location of an intruder; and at least one reflective means reflecting the emitted laser beam toward the laser beam finder, wherein at least one reflective means is spaced by a predetermined distance of the laser range finder and is installed a predetermined distance from the laser range finder.