摘要:
A networked system for managing a physical intrusion detection/alarm includes a network of end nodes, e.g., sensor nodes including one or more constrained sensor nodes for sensing physical conditions, and a gateway to provide network connections for the constrained sensor nodes. The system also includes a range extender for connecting the one or more constrained sensor nodes to the gateway, with the range extender including first and second radios and corresponding processors to wirelessly communicate with the gateway and constrained nodes.
摘要:
A method and system for processing radio frequency identification (“RFID”) communication device data, the method and system including measuring an energy level of a RFID signal received on a first communication channel, measuring an energy level of the RFID signal received on a second communication channel, selecting the communication channel with the greater energy level, and acquiring data samples from the RFID signal received on the selected channel. The method and system for processing RFID communication device data can further include generating a preamble from a series of the acquired data samples.
摘要:
In an electronic article surveillance system, quadrature transmitting and receiving antennas are used to improve field distribution. A transmitting antenna arrangement includes first and second adjacent co-planar antenna loops and excitation circuitry for generating respective alternating currents in the first and second loops such that the respective alternating currents are 90.degree. out of phase. In a receiving arrangement, respective signals received from two adjacent co-planar antenna loops are respectively phase-shifted by +45.degree. and -45.degree., and the resulting phase-shifted signals are summed. A far-field cancelling transmitting antenna arrangement includes four loops operated at phases of 0.degree., 90.degree., 180.degree. and 270.degree. respectively. All four loops may be co-planar, with any bucking vertical segments being horizontally displaced from each other. Alternatively, the 0.degree. and 180.degree. loops may also be arranged in a common plane that is close to and parallel with another plane in which the 90.degree. and 270.degree. loops are arranged.
摘要:
A communication system (10) receiving a communication signal from a far communication system (12) has a channel selector, and a number of local transceivers (22) forming a first broadcast array and a second channel searching array. The first broadcast array is configured to receive the communication signal and transmit a local communication signal on channels. Each local transceiver is connected to a controller (32). The controller is configured to remove noise from the far communication signal. The noise includes interference from the local transceivers being received on the channel. The controller measures a parameter of at Least one of the channels. The controller determines an availability of one or some channels using the second channel searching array. The second channel searching array outputs an available channel signal to the controller. The controller (32) communicates the availability to at least one of the first broadcast array to transmit and to receive the far communication signal on the available channel.
摘要:
A networked system for managing a physical intrusion detection/alarm includes a network of end nodes, e.g., sensor nodes including one or more constrained sensor nodes for sensing physical conditions, and a gateway to provide network connections for the constrained sensor nodes. The system also includes a range extender for connecting the one or more constrained sensor nodes to the gateway, with the range extender including first and second radios and corresponding processors to wirelessly communicate with the gateway and constrained nodes.
摘要:
A product tag system comprises: an RFID tag adapted for attachment to a product; a data store in the tag for bar code information relating to the product; a tag detacher for removing the tag from the product at a point of sale; an RFID tag reader for retrieving the bar code information from the tag when the tag is placed in the tag detacher; and, an display for presenting the bar code information in a form which can be scanned by a conventional bar code scanner, and/or in human readable form. A method for monitoring products comprise the steps of: attaching an RFID tag to a product; writing bar code information onto the tag; retrieving the bar code information from the tag at a point of sale; displaying the bar code information in a form which can be scanned by a conventional bar code scanner, and/or in human readable form; and, detaching the tag from the product.
摘要:
In an electronic article surveillance system, quadrature transmitting and receiving antennas are used to improve field distribution. A transmitting antenna arrangement includes first and second adjacent co-planar antenna loops and excitation circuitry for generating respective alternating currents in the first and second loops such that the respective alternating currents are 90.degree. out of phase. In a receiving arrangement, respective signals received from two adjacent co-planar antenna loops are respectively phase-shifted by +45.degree. and -45.degree., and the resulting phase-shifted signals are summed. A far-field cancelling transmitting antenna arrangement includes four loops operated at phases of 0.degree., 90.degree., 180.degree. and 270.degree. respectively. All four loops may be co-planar, with any bucking vertical segments being horizontally displaced from each other. Alternatively, the 0.degree. and 180.degree. loops may also be arranged in a common plane that is close to and parallel with another plane in which the 90.degree. and 270.degree. loops are arranged.