Abstract: An identification device formed from a band of material and a non-reusable tamper-resistant fastening arranged to join opposite end regions of the band. A radio frequency identification (RFID) transponder is disposed on the band. The transponder includes an RFID circuit, such as may be formed on an integrated circuit (IC) chip, and an antenna. First and second electrically conductive traces are coupled to different portions of the RFID transponder. The first and second traces are arranged such that the RFID transponder is disabled when the first and second electrically conductive traces come in contact with one another. Various arrangements of the conductive traces are described to achieve improved security and functionality over the prior art.

Abstract: The control of fluid introduction into and out of body conduits such as vessels, is of great concern in medicine. As the development of more particular treatments to vessels and organs continues it is apparent that controlled introduction and removal of fluids is necessary. Fluid delivery and removal from such sites, usually referred to as irrigation and aspiration, using fluid exchange devices that control also need to be considerate of potential volume and/or pressure in the vessel or organ are described together with catheter and lumen configurations to achieve the fluid exchange. The devices include several electrically or mechanically controlled embodiments and produce both controlled and localized flow with defined volume exchange ratios for fluid management. The applications in medicine include diagnostic, therapeutic, imaging, and uses for the introduction or removal of concentrations of emboli within body cavities.

Abstract: A tamper-resistant RFID wristband that becomes permanently disabled upon tampering. The wristband includes a plurality of holes for snugly securing the band to a wearer, an RFID circuit, and an electrically conductive loop disposed in the band. The RFID circuit and the conductive loop are electrically coupled to form a series circuit, severance of which disables the wristband. The electrically conductive loop includes a first layer and a second layer that are electrically isolated from one another, save for at least one electrical connection made preferably by a via at the end of the band distal from the antenna element. The first layer encircles the holes in a serpentine path on one layer of the band and the second layer encircles the holes in a complimentary serpentine path on a different layer of the band.

Abstract: Apparatus and methods are described for effective removal of emboli or harmful fluids during vascular procedures, such as angiography, balloon angioplasty, stent deployment, laser angioplasty, atherectomy, intravascular ultrasonography and other therapeutic and diagnostic procedures. A catheter with an occluder mounted at its distal end creates an occlusion proximal to the lesion. The catheter provides a pathway for introducing a treatment catheter. Prior to, during or subsequent to the procedure, suction is activated to establish retrograde flow to remove emboli from the site. Additionally, a thin catheter with a distal fluid ejection nozzle maybe introduced distal to the treatment site to rinse emboli from the treatment site. The suction flow and/or ejected fluid flow may be varied in a pulsatile manner to simulate regular blood flow and/or perturb settled emboli into being captured that may otherwise not be collected.

Abstract: A tamper-resistant RFID identification apparatus that includes a mechanism for storing an excess portion of the apparatus when engaged. The apparatus includes a substrate including a series of holes along a length thereof and a slot distal from the series of holes, a tamper-resistant locking mechanism for securing the apparatus to an object, an RFID circuit disposed on the substrate and an electrically conductive loop disposed on the substrate and electrically coupled to the RFID circuit, that is arranged to disable the RFID circuit when cut. The slot receives a tail portion of the substrate when the apparatus is secured.

Abstract: A channel access system is described in which a number of slots within a contention window are available for assignment to streaming data transmitters. The other slots are selected by the other transmitters according to a CSMA/CA transmit protocol.

Abstract: An identification device has a band and a non-reusable tamper-resistant fastening arranged to join opposite end regions of the band to fasten it around a limb of a user. A transponder circuit is attached to the band, and is responsive to a received wireless signal. In response to the received wireless signal, the transponder emits a wireless signal representative of information pre-stored in the transponder. An electrically conductive continuous loop on the band extends from the transponder and forms an electrically continuous path along substantially the entire length of the band, the loop being frangible and easily broken in response to an attempt to remove the band from the wearer's limb. Circuitry in the transponder is electrically connected to the loop and arranged to become inoperative and disable the transponder if the loop is broken.

Abstract: An identification device formed from a band of material and a non-reusable tamper-resistant fastening arranged to join opposite end regions of the band. A radio frequency identification (RFID) transponder is disposed on the band. The transponder includes an RFID circuit, such as may be formed on an integrated circuit (IC) chip, and an antenna. First and second electrically conductive traces are coupled to different portions of the RFID transponder. The first and second traces are arranged such that the RFID transponder is disabled when the first and second electrically conductive traces come in contact with one another. Various arrangements of the conductive traces are described to achieve improved security and functionality over the prior art.

Abstract: Orthogonal frequency division multiplexing (OFDM) receiver embodiments of the invention provide data demodulator synchronization by finding the end of the short preamble in an IEEE-802.11a burst transmission. This method exploits the fact that there are certain symmetries in the long-preamble that can be used to determine synchronization. The long-preamble sequence is composed of a guard interval (GI) and two long-preamble symbols; the GI is the last 32 samples of the long-preamble symbol. The 32nd sample of the long-preamble acts as a “pilot” or “anchor” sample in that the previous N and subsequent N samples are complex conjugates, or conjugate “mirror” vectors. Due to the periodicities of the long-preamble, this property repeats every 32 samples. No other samples in the long preamble exhibit this property. Coherent combining is used in one embodiment for robustness.

Abstract: An identification apparatus, such as may be incorporated into a band of material used as a wristband. An identification function is disposed in the band, along with an Electronic Article Surveillance (EAS) function, that may be selected to be at least one of an electromagnetic or acousto-magnetic segment. The identification function is typically a Radio Frequency Identification (RFID) device. The EAS function segment operates independently of the RFID device, so that the presence or absence of one or more EAS segments can be detected without affecting the RFID function operation. In one embodiment, multiple segments are disposed on the band, with at least one segment having a different characteristic physical property than at least one other segment. The multiple segments may be formed on an upper and lower surface of the band, such that they overlap with one another in a vertical plane.

Abstract: A tamper-resistant RFID wristband that becomes permanently disabled upon tampering. The wristband includes a plurality of holes for snugly securing the band to a wearer, an RFID circuit, and an electrically conductive loop disposed in the band. The RFID circuit and the conductive loop are electrically coupled to form a series circuit, severance of which disables the wristband. The electrically conductive loop includes a first layer and a second layer that are electrically isolated from one another, save for at least one electrical connection made preferably by a via at the end of the band distal from the antenna element.

Abstract: A process for electronic authorization to access a common account via personal identification devices such as Radio Frequency Identification (RFID) tags, such as may be mounted on a wristband. RFID wristbands for auxiliary users are not authorized by a cashier/operator unless a primary account holder's RFID wristband is utilized as an immediate preceding step. This process alleviates a problem with simpler approaches which merely require operator authorization to associate auxiliary RFID wristbands with primary RFID wristbands.

Abstract: A method for manufacturing an RFID disabling apparatus using prefabricated, “off-the-shelf” components. The method includes: disposing a prefabricated RFID circuit and a conductive loop on a substrate, coupling a first end of the conductive loop to a first endpoint of the RFID circuit, and coupling a second end of the conductive loop to a second endpoint of the RFID circuit. An optional electronic component can be coupled between the first endpoint and the second endpoint of the RFID circuit. The RFID circuit can be an “off-the-shelf” RFID circuit. A portion of the RFID circuit can be severed to create the first endpoint and the second endpoint.

Abstract: Many communications protocols involve a collection of communication channels collectively forming the dimensions of a finite dimensional vector space, of which at any point in time, only a subset of those channels or dimensions must be received. Messages on these channels are time progressions in at least the actively used dimensions of the vector space which have been linearly transformed to create a sample list transported across at least one physical transport layer to a receiver. The linear transform may further include an estimation of the effects of the transport of the sample list across the one or more physical layers to the receiver. This invention uses at least portions of pseudo-inverses of the linear transform in various ways within receivers and receiver portions of transceivers.

Abstract: Orthogonal frequency division multiplexing (OFDM) receiver embodiments of the invention provide timing misalignment estimation by calculating the intra-baud timing differential. The preferred method exploits the spectral structure of the short-preamble in that a time delay in the time-domain is manifest as a phase rotation in the frequency-domain. The timing misalignment is determined by special processing the spectral peaks of the modified short-preamble. An alternative embodiment linearly combines the two long-preamble symbols to construct a single “best estimate” long-preamble symbol. A normalized dot product of the “best estimate” long-preamble symbol and the ideal on-baud symbol is computed to obtain the magnitude of the timing misalignment. A dot product between the “best estimate” long-preamble symbol and the time derivative of the ideal on-baud sampled sequence is computed to obtain the sign of the timing misalignment.

Abstract: An identification device has a band and a non-reusable tamper-resistant fastening arranged to join opposite end regions of the band to fasten it around a limb of a user. A transponder circuit and antenna are attached to the band, so that they are responsive to a received wireless signal. In response to the received wireless signal, the transponder emits a wireless signal representative of information pre-stored in the transponder. An electrically conductive continuous loop on the band couples to the transponder and forms an electrically continuous path along substantially the entire length of the band. The conductive loop also serves as an extension of antenna, so that the transponder is thus arranged to become inoperative and disable the transponder if the loop is broken.

Abstract: A non-reusable tamper-resistant identification device, such as may be fastened around a limb of a user. A Radio Frequency Identification (RFID) circuit is disposed in a band of material, such as is suitable for use as a wristband. The RFID circuit comprises an antenna and a transponder, disposed adjacent the antenna and cooperating therewith for emitting and receiving a wireless signal. An electrically conductive loop forms at least a portion of a connection between the antenna and the transponder. In addition, the electrically conductive loop forms a continuous conductive path along substantially the entire length of the band. The conductive loop is preferably frangible and easily broken in response to an attempt to remove the band from the wearer's limb.

Abstract: Orthogonal frequency division multiplexing (OFDM) receiver embodiments of the invention demodulate quadrature amplitude modulated (QAM) signals transmitted in the five GHz frequency band and digitally correct for frequency offset errors in their digital signal processing (DSP) units. A method comprises a step in which an OFDM transmission is I/Q sampled and a portion of the received packet is selected. It is assumed that the coarse frequency offset has been estimated and that the remaining frequency offset after coarse frequency offset compensation does not exceed ±10 kHz (valid for 802.11a PHY implementation only). It is also assumed that a timing reference has been determined. A cost function is used to determine a fine-frequency offset. Once the fine frequency offset is determined, the estimate is used in the downstream digital signal processing.

Abstract: The control of fluid introduction into and out of body conduits such as vessels, is of great concern in medicine. As the development of more particular treatments to vessels and organs continues it is apparent that controlled introduction and removal of fluids is necessary. Fluid delivery and removal from such sites, usually referred to as irrigation and aspiration, using fluid exchange devices that control also need to be considerate of potential volume and/or pressure in the vessel or organ are described together with catheter and lumen configurations to achieve the fluid exchange. The devices include several electrically or mechanically controlled embodiments and produce both controlled and localized flow with defined volume exchange ratios for fluid management. The applications in medicine include diagnostic, therapeutic, imaging, and uses for the introduction or removal of concentrations of emboli within body cavities.

Abstract: A method and apparatus are provided that performs timing acquisition for multiple radio terminals. According to one aspect of the present invention the invention includes receiving a sequence of symbols modulated onto a carrier frequency over a channel and demodulating the symbols using a clock frequency. The invention further includes determining a frequency offset of the received symbols with respect to the clock frequency and applying the determined frequency offset to adjust the clock frequency.