摘要:
Provided is a method for determining superframe to efficiently perform beacon scheduling by allocating superframe lengths which are different according to a routing depth of sensor nodes in a ZigBee based wireless sensor network. The method for determining a superframe for beacon scheduling, includes the steps of: receiving a beacon from a neighboring node and grasping information on a superframe used by the neighboring nodes; and determining a transmission time and a length of own superframe based on superframe information of the grasped neighboring node.
摘要:
Provided is a planar inverted-F antenna (PIFA) which has a Co-Planar Waveguide (CPW) feeding structure and can be attached to a metal surface, and an RFID tag using the same. The PIFA includes a radiation patch layer; a Co-Planar Waveguide (CPW) feeding layer; a feeding probe; and a short-circuit. The CPW feeding layer includes a feeding means and a ground surface. The feeding probe electrically connects the radiation patch layer and the feeding means and provides a Radio Frequency (RF) signal to be radiated to the radiation patch layer. The short-circuiting means short-circuits the radiation patch layer and the ground surface through the dielectric layer. The PIFA can be applied to a passive RFID tag. Impedance matching between the antenna and the RFID chip is possible. Also, the PIFA can easily control resonant frequency of the antenna and reactance.
摘要:
Provided is an antenna based on proximity coupling between a short-ended microstrip feed line and a radiation patch, an RFID tag including the planar antenna, and an antenna impedance matching method thereof. The antenna includes a radiation patch configured to determine a resonant frequency of the antenna; a ground plate disposed in parallel to the radiation patch; and a feeding part disposed between the radiation patch and the ground plate and configured to provide radio frequency signals to a device connected to the antenna. The feeding part includes a feed line that is formed in a resonance length direction of the radiation patch and proximity-coupled with the radiation patch and one end of the feed line is shorted. The antenna freely controls the resistance and reactance of the antenna impedance independently and efficiently matched to a device connected to the antenna which has a predetermined impedance in wide bands.
摘要:
Provided are a tag signal receiving apparatus that can perform digital Amplitude Shift Keying (ASK) demodulation onto signals received in a tag, decode the demodulated tag signal in synchronization, and acquire tag data in a mobile RFID reader, and a method thereof. The tag signal receiving apparatus includes: a digital demodulating block for performing ASK demodulation onto a digital tag signal received through a reader antenna and converted into a digital tag signal in an analog-to-digital (AD) converter; and a decoding block for detecting edge position information of the demodulated tag signal by performing accumulation and decoding the demodulated tag signal by using the detected edge position information. The digital demodulating block includes a channel level comparator, a phase inverter, a signal converter; and an adder. The decoding block includes an edge information detector, a correlator, and a bit data decider.
摘要:
Provided is a power amplifier sharing system for a mobile communication system having a mobile Radio Frequency Identification (RFID) function, particularly, a power amplifier sharing system that can reduce the power consumption and the size of a circuit in a mobile communication terminal having a mobile RFID function. The system includes a mobile communication transceiver for transmitting/receiving a mobile communication signal; a mobile RFID transceiver for transmitting/receiving a mobile RFID signal; a power amplifier for amplifying a signal; a switch for connecting the mobile communication transceiver and the mobile RFID transceiver to the power amplifier; and a transceiver controller for controlling the switch and the power amplifier.
摘要:
The present invention relates to a sensor network having node architecture for performing trust management of neighboring sensor nodes, and to an adaptive method for performing trust management of neighboring sensor nodes for monitoring security in the sensor network. The sensor network includes a base station and a plurality of sensor nodes for reporting sensed information packets to the base station through radiofrequency signals relayed by other sensor nodes. A judge sensor node may have a trust estimator in its node architecture to evaluate trustworthiness of a neighboring suspect sensor node by determining a personal reference and receiving personal references from jury sensor nodes. Based on the trustworthiness of the suspect, the judge may modify a route for transmitting packets to the base station.
摘要:
An apparatus for storing sensing data in a tag and a method thereof are provided. According to the present invention, data measured by the sensor is stored in volatile memory and important data from among the data stored in the volatile memory is stored in non-volatile memory according to a pre-set data loss prevention mechanism so that a battery and the tag including the battery have a longer life and stability of data can be secured.
摘要:
The present invention provides a method and apparatus for assigning a channel in an ad-hoc network, which can minimize beacon collision in the ad-hoc network and prevent channel overlapping or collision, and thus a channel can be efficiently assigned. The method of assigning a channel including: obtaining join order information which is information on the order in which a first node has been joined to a second node, which is a parent node, and level information of the second node in an ad-hoc network; determining a reference value for setting a channel that is to be assigned to the first node based on an address value of the first node, which is determined based on the join order information and the level information, a level value of the first node, a channel value of the second node, which is determined based on the level information, and the join order information; and determining a channel value of the first node by dividing the reference value by the maximum number of usable channels in the ad-hoc network.
摘要:
Provided are a method and apparatus for sharing a portable terminal in a Code Division Multiple Access (CDMA) and a mobile Radio Frequency Identification (RFID) system. The portable terminal includes: a CDMA mobile station system for performing CDMA communication; a mobile RFID system for performing a passive RFID reader function; a switching unit for switching an antenna to any one between the CDMA mobile station system and the mobile RFID system; and a control unit for controlling the switching unit to connect the antenna to the CDMA mobile station system when the portable terminal transmits/receives a signal to/from the base station, or connect the antenna to the mobile RFID system when the portable terminal transmits/receives a signal to/from an RFID tag.
摘要:
The present invention relates to a mobile radio frequency identification (RFID) reader and a RFID communication method using a shared system clock. According to the present invention, clock for synchronizing the mobile RFID readers can be shared without changing hardware of a conventional RHD device. Also, since the shared clock is used, a technology for preventing a collision with the readers can be easily realized in a mobile multi-reader environment.