Sandlinks Systems Ltd. Patent applications |
Patent application number | Title | Published |
20100177803 | ULTRA WIDEBAND ON-CHIP PULSE GENERATOR - A method for generating an UWB pulses based on LC oscillator topology. Fast turn on of the oscillator is achieved by creating large asymmetry in a normally symmetrical topology which is used in a typical differential type oscillator. One method for achieving large asymmetry is activating one branch of a differential pair of branches for a short duration before activating both branches in a normal operation. The bandwidth of the pulse is controlled by modifying the duration of the oscillator activation. Fast turn on and turn off is essential for high bandwidth generation. The method is adaptable for generating binary phase shift keying (BPSK) modulation. Selecting the activated branch of a fully symmetrical topology controls the output phase and creates two possibilities which differ exactly by 180 degrees. In a preferred embodiment, all the pulse generator components are on-clip leading to a low cost solution. The circuit can generate high power pulses directly on a load. It is also an option to add an amplifier to drive the output and separate the load from the oscillator. This method generate high power, stable pulses under varying practical conditions like process changes, VDD changes and temperature changes. | 07-15-2010 |
20100164690 | ARRAY OF VERY LIGHT READERS FOR ACTIVE RFID AND LOCATION APPLICATIONS - The Very Light Readers of the present invention are based on an augmented Tag circuit with a preferred embodiment including at least one VLSI chip integrating a UWB front end, digital transceiver, and possibly an internal controller; a UWB Antenna; a power supply; a controller configured to implement the Media Access Control protocol of the system; a Communication Interface subsystem for connection to the system network and a clock source. Also described is a system capable of reducing collision occurrence in a network for communicating between multiple readers and a plurality of RF Tags. Tags are configured to receive interrogation signals and transmit response signals. Readers are configured to transmit interrogation signals, receive response signals, estimate the quantity of responses received to an interrogation, determine the round trip delay time of each response and estimates whether a collision between responses has occurred. If so, the Reader transmits an additional interrogation signal. The Reader also transmits an acknowledgment packet to responding Tags so responding Tag will not answer again to that broadcast session. Other Readers in the network also receive the acknowledge packet and do not try again to reach the responding Tags, thereby lowering congestion directed toward Tags from multiple Reader transmissions. | 07-01-2010 |
20100148961 | ACTIVE VIRTUAL FENCE USING MESH NETWORKED RF TAGS - A system capable of monitoring an area and detecting a disturbance with the area. The system has a plurality of ultra-wide band radio frequency tags, each of the tags including a digital signal processing module configured to monitor changes in radio frequency multipath properties of received packets transmitted by at least one other of the tags. Changes in the radio frequency multipath properties may be caused by a disturbance indicative of an object in the vicinity of the tags. A corresponding method is also disclosed. | 06-17-2010 |
20100148925 | WIDE-AREA DYNAMIC RFID SYSTEM USING UWB - A wide area radio frequency identification (RFID) system includes: a first RFID cell and a second RFID cell. The first RFID cell and the second RFID cell each include a reader and tags. The readers access the tags using ultra-wide band signaling. The RFID cells each include: a communications interface operable to communicate with a network operations center, and a communications gateway which supports direct communications between RFID cells. The method includes accessing the second RFID cell from the first RFID cell, and the accessing is performed using the communications gateway that can cover a range of at least five hundred meters. | 06-17-2010 |
20090185505 | MEDIA ACCESS CONTROL (MAC) FOR AN ACTIVE RFID SYSTEM - A system of radio frequency communication between Readers and Tags, the system comprising at least one tag Reader and a plurality of Tags, each tag is given a unique tag ID, deployed in a region in which at least some of the Tags are in radio communication with the tag Reader and a Media Access Control protocol such that the tag Reader is configured to send and receive radio communication to and from at least some of the plurality of Tags. The plurality of Tags are configured to send and receive radio communication to and from the tag Reader and the Media Access Control protocol is configured to control the radio communication between the tag Reader and the plurality of Tags The Media Access Control protocol includes a multi-dimensional addressing scheme allowing Readers to efficiently address tag communities ranging from small to very large in unicast, multicast and broadcast modes. The multi-dimensional addressing scheme enables division of the plurality of Tags into a number of groups for different stages of Media Access Control protocol processing, based on different portions of the tag ID. A hash function is used to transform the tag ID into a pseudo random ID, so as to achieve better spreading of tag population and lower statistical dependency between dimensions. The MAC has an inherent flexibility in the sense that it allows readers to communicate with different versions of tags and also to optimize communication parameters to reader's capabilities, without pre-configuration of the tags. Furthermore, the MAC supports means to achieve very high access reliability, such as relay between tags, and the ability to work with tags that alternate between active and sleep mode) including means for power savings. All of these novel features, coupled with some prior art concepts like collision resolution algorithms, result in a scalable MAC protocol for an active RFID system employing multiple access. | 07-23-2009 |
20090103671 | Low Power Fast Impulse Radio Synchronization - A method for synchronizing on a pulsed waveform sequence including pulsed waveforms. An impulse radio receiver is provided including a radio frequency (RF) front end connected to a demodulator, and the demodulator is connected to a processing unit. Power is provided to at least a portion of an RF component such as the RF front end and/or the demodulator, during time windows sufficient for testing an hypothesis regarding timing of the pulsed waveforms. The powering is controlled by the processing unit. Preferably, testing the hypothesis includes accumulating a signal of the pulsed waveforms, correlating with the pulsed waveforms, or accumulating the correlation result of the pulsed waveforms. Preferably, others functions of the receiver are powered or enabled subsequent to the testing. Preferably, the impulse radio receiver is an ultra-wide band receiver. | 04-23-2009 |
20090079580 | VIRTUAL GROUP MAINTENANCE AND SECURITY - The present invention relates to a method and system ( | 03-26-2009 |
20080224869 | Rfid-Uwb System Connected to Wlan Infrastructure - A system including a radio frequency identification (RFID) network and a wireless local area network (WLAN). The RFID network transfers ultra-wide band signals between a reader and a tag. In the wireless local area network (WLAN) an access point communicates with a WLAN transceiver using WLAN signals. The reader is operatively attached to either the wireless access point or the WLAN transceiver and the WLAN is a back haul network of the RFID network. Co-existence of the two networks is provided either by time division between the ultra-wide band signals and WLAN signals; and/or receiver isolation of said RFID network from said WLAN signals. | 09-18-2008 |