摘要:
A microstrip patch array antenna suppressing side lobes. The microstrip patch array antenna have a plurality of antenna array elements on two-dimensional planar having A axis and B axis for suppressing side lobes, wherein the antenna array elements are linearly arranged in a direction of the A axis by spacing a first predetermined distance between the antenna array elements, the arranged array elements are arranged in a direction of the B axis by spacing a second predetermined distance between the antenna array elements and a predetermined portion of the microstrip patch array antenna having the arranged array elements are horizontally shifted to a predetermined distance. The present invention can reduce leakage of signal or prevent to receive undesired signal and to transmit signals to undesired direction by using the above mentioned array pattern instead of reducing a distance of spacing between antenna elements.
摘要:
An apparatus and method of generating a pseudo noise (PN) code is provided. The apparatus for generating the PN code includes: a memory device unit including a plurality of memory devices; an exclusive-OR (XOR) operation unit receiving output values of at least two memory devices among output values of the plurality of memory devices to output an XOR operation value with respect to the received output values; and a PN code generation unit generating the PN code based on an output value of the XOR operation unit.
摘要:
Provided is a resource allocation method performed in a wireless network formed of a plurality of nodes, the resource allocation method including the operations of forming clusters and electing cluster heads respectively for the clusters; determining whether a node from among the plurality of nodes forming the wireless network is an edge node; if the node is not the edge node according to a result of the determining, collecting link information related to other nodes in a cluster that comprises the node, and delivering the link information to a cluster head of the cluster; and if the node is the edge node according to a result of the determining, otherwise, obtaining link information and scheduling information from an edge node of another cluster within a communication range with the cluster comprising the edge node, and delivering the link information and scheduling information to the cluster head. The resource allocation method decentralizes a load of calculations to several nodes, wherein the load may be centralized to one node in a large ad-hoc network, so that an energy efficiency of the node may be increased, and since the several nodes sequentially perform simple calculation, a total of the resource allocation time may be reduced.
摘要:
A method of operating a device capable of periodically hopping a predetermined interval using a channel hopping sequence in order to improve low radio frequency (RF) reliability caused by single frequency based channel access.
摘要:
There is provided a mesh routing method in beacon-enabled wireless AD-HOC networks that includes: broadcasting, by nodes constituting a wireless AD-HOC network, a beacon message loading neighbor node information on a beacon payload; managing, by a node receiving the broadcasted beacon message, its own neighbor node table by extracting the neighbor node information loaded on the beacon payload; and performing, by a source node attempting to transmit data or commands, mesh routing on the basis of its own neighbor node table.
摘要:
The RFID reader of an RFID system includes a processor for processing a command for the RFID tag and a response from the RFID tag, a modem for modulating the command from the processor or demodulating the response from the RFID, and an RF unit for transmitting the modulated command transferred from the modem to the RFID tag or receiving the response from the RFID tag and transferring the response to the modem. The RFID tag of the RFID system includes a power supply unit for generating energy using a radio wave received from the RFID reader, a receiver for demodulating a signal received from the RFID reader, a data processor for performing operation according to the signal demodulated by the receiver, and a transmitter for backscattering a signal from the data processor.
摘要:
A battery-powered RFID tag capable of reducing power consumption and a method of waking up the RFID tag are provided. The battery-powered RFID tag has an activated mode where a general command is detected by decoding a signal received from an RFID tag reader and the general command is executed and a standby mode where the general command is not detected. If a voltage of a continuous wave detected from the signal is equal to or higher than a predetermined voltage or if a wake-up command is detected from the signal, the state of the RFID tag is changed from the standby mode to the activated mode. In addition, the RFID tag is driven by a higher one between the voltage of the continuous wave and a voltage of a built-in battery.
摘要:
A super frame structure supporting a mesh network, and a beacon scheduling method. The super frame structure and the beacon scheduling method may support a mesh topology in a beacon enabled mode, may have an algorithm that is simple and easily realized via beacon scheduling using a distribution method, and may easily adapt to changes in a network environment.
摘要:
A medium access control (MAC) technique of a multihop sensor network. In the multihop sensor network, the MAC technique may contribute to significantly reducing transmission delay, and allow real-time services to be provided to all nodes by extending a guaranteed time slot (GTS) restricted to one hop in a personal area network (PAN) coordinator (PNC) to all nodes. Furthermore, the MAC technique may allow the number of available GTSs to be significantly increased, by using all 16 frequency band channels instead of using only a single frequency band and setting a multi-superframe.
摘要:
There is provided a mesh routing method in beacon-enabled wireless AD-HOC networks that includes: broadcasting, by nodes constituting a wireless AD-HOC network, a beacon message loading neighbor node information on a beacon payload; managing, by a node receiving the broadcasted beacon message, its own neighbor node table by extracting the neighbor node information loaded on the beacon payload; and performing, by a source node attempting to transmit data or commands, mesh routing on the basis of its own neighbor node table.