摘要:
Methods, systems, and apparatuses for reading tags of tag populations are described. Rather than interrogating a tag population in a single query round, interrogations of tag populations are performed using reduced transmit power levels over multiple query rounds, each query round reading a portion of the tag population. In this manner, an overall power amount expended to transmit interrogations signals is reduced, while maintaining a substantially similar read rate as in single query round interrogations.
摘要:
RFID methods, systems and apparatus for writing common data (RFID information) to a plurality of RFID tags, include transmitting a common-write data signal including the common data to a plurality of RFID tags located in a broadcast field, where the plurality of RFID tags receive and respectively write the common data in internal memory of the plurality of RFID tags in accordance with a common algorithm. A common-write data signal may include common identifier data. Each of a plurality of RFID tags may generate common identifier data by controlling a random number generator of the tag. Each of a plurality of RFID tags may be pre-configured (initialized) for receiving common data and writing the common data to memory in accordance with a common algorithm. Each of a reader and a plurality of RFID tags may include common algorithm for transmitting/receiving and executing a common-write-enable command that enables a common write capability of a tag (e.g., initializes a tag for receiving a common-write data signal), and for transmitting/receiving a common-write-disable command that disables common-write capability of a tag.
摘要:
An apparatus, system and techniques for determining a location of an RFID tag among a population of tags are disclosed. The system includes an RFID reader with at least one antenna port and a population of RFID tags. The population of tags can be homogenous or heterogeneous. The RFID reader varies its transmit power through one or more antenna ports resulting in a grouping of the RFID tags into clusters. In one embodiment, the reader utilizes multiple antennas to further define RFID tag clusters among the population. Each read tag is then uniquely associated with a defined cluster. Tag agents also can be provided among the population of tags facilitating definition of the clusters.
摘要:
A transmission device that transmits a signal along a link and method therefor that includes a forward error correction encoder unit to insert error correction information into the signal transmitted along a link and output a corresponding encoded signal. A modulation unit variably modulates the encoded signal and outputs a modulated signal, having a corresponding quadrature amplitude modulation index, to the receiving device. A control unit variably controls the inserted forward error correction information and the quadrature amplitude modulation index based on link quality information with respect to substantially the entire link to increase throughput during periods of reduced environmental degradation.
摘要:
Methods, systems and apparatuses for RFID readers forming a reader network are described. In an aspect of the present invention, a plurality of RFID readers are configured to interrogate tags. Furthermore, the readers are configured to communicate with one another by transferring a token, represented by a signal. Possession of the token enables the reader to access a RF communications medium. Readers can be arranged in a ring configuration, and interconnected via wired links. A secondary token may circulate in the ring in addition to the primary token, to ensure redundancy in the system. A reader waits for a predetermined time interval before accessing the RF communications medium.