Abstract: An apparatus, method and system for cannulation of blood vessels. The apparatus comprises a sensor assembly including two linear transducer arrays oriented perpendicular to each other to form a “T” shape to provide ultrasound images of at least one blood vessel in a portion of a patient's body in two perpendicular planes and optionally determine flow direction within the at least one blood vessel. The sensor assembly may be disposed within a graphically marked cover to facilitate orientation of the sensor assembly on the patient and guidance of a needle towards a desired target vessel during the cannulation procedure. The cover may also include associated structure to cooperate with a reference location element to place, align and secure the sensor assembly to the patient's skin at a desired location.

Abstract: An apparatus, method and system for cannulation of blood vessels. The apparatus comprises a sensor assembly including two linear transducer arrays oriented perpendicular to each other to form a “T” shape, to provide ultrasound images of at least one blood vessel in a portion of a patient's body in two perpendicular planes. The sensor assembly may be disposed within an elongated, flexible, protective sheath and secured to a frame to facilitate orientation of the sensor assembly on the patient and guidance of a needle towards a desired target vessel during the cannulation procedure. The sensor assembly may also include associated structure to cooperate with a reference location element to place, align and secure the sensor assembly to the patient's skin at a desired location.

Abstract: An apparatus, method and system for cannulation of blood vessels. The apparatus comprises a sensor assembly including two linear transducer arrays oriented perpendicularly to each other to form a “T” shape to provide substantially simultaneous ultrasound images of at least one blood vessel in a portion of a patient's body in two perpendicular planes. The apparatus may also include one or more Doppler transducer elements to transmit and receive one or more Doppler beams at an incident angle beneath one of the transducer arrays and in alignment therewith to determine blood flow direction and velocity within the at least one blood vessel. The sensor assembly may be disposed within an elongated, flexible, protective sheath and secured to a graphically marked cover to facilitate orientation of the sensor assembly on the patient and guidance of a needle towards a desired target vessel during the cannulation procedure.

Abstract: The present invention synthesizes a prescribed impedance. The impedance is synthesized by generating a current having a value substantially equal to a voltage divided by a prescribed impedance. Sensing the line voltage and converting that sensed line voltage to its digital equivalent accomplish this first step. The digital line voltage is processed by a factor related to the prescribed impedance to produce an output voltage that has a value substantially equal to the sensed voltage divided by the prescribed impedance. The output voltage controls a voltage to current converter that generates the appropriate current across the points or terminals where the line voltage was measured. Thus, the prescribed impedance is generated across these points or terminals because the line voltage divided by the generated current is substantially equal to the prescribed impedance.

Abstract: The present invention provides apparatus and methods for attenuating signals received from a source over a data transmission line, having an unknown resistance, to achieve optimized signals in various data terminal and data communications equipment. In a preferred embodiment, a resistor network is operably coupled between the transmission line and a means for processing the signal, such as a digital processor, an ADC and a DAC. The resistor network comprises a termination resistor that is associated with a termination voltage, a variable resistor and another resistor. During use, a switch is operably positioned between a plurality of switch positions so that two voltage measurements will lead to the determination of the voltage of the source and the termination voltage within the resistor network. Once these voltages are known, the unknown resistance can be estimated.

Abstract: An apparatus, method and system for cannulation of blood vessels. The apparatus comprises a sensor assembly including two linear transducer arrays oriented perpendicular to each other to form a “T” shape, to provide substantially simultaneous ultrasound images of at least one blood vessel in a portion of a patient's body in two perpendicular planes. The apparatus may also include one or more Doppler transducer elements to transmit and receive one or more Doppler beams at an incident angle beneath one of the transducer arrays and in alignment therewith to determine blood flow direction and velocity within the at least one blood vessel. The sensor assembly may be disposed within an elongated, flexible, protective sheath and secured to a graphically marked cover to facilitate orientation of the sensor assembly on the patient and guidance of a needle towards a desired target vessel during the cannulation procedure.

Abstract: This invention describes a novel method and system that implements wavelet packet trees and inverse wavelet packet trees. A modified Recursive Pyramid Algorithm (RPA) is advanced by this invention. The algorithm uses a filter that changes its size at each given octave of the wavelet packet tree. This filter may also be used in the reconstruction, synthesis, or inverse wavelet packet tree using RPA. The invention reduces the cost of implementing wavelet packet trees by using the same hardware for each octave and thereby offers superior products at attractive prices.

Abstract: The present invention synthesizes a prescribed impedance. The impedance is synthesized by generating a current having a value substantially equal to a voltage divided by a prescribed impedance. Sensing the line voltage and converting that sensed line voltage to its digital equivalent accomplish this first step. The digital line voltage is processed by a factor related to the prescribed impedance to produce an output voltage that has a value substantially equal to the sensed voltage divided by the prescribed impedance. The output voltage controls a voltage to current converter that generates the appropriate current across the points or terminals where the line voltage was measured. Thus, the prescribed impedance is generated across these points or terminals because the line voltage divided by the generated current is substantially equal to the prescribed impedance.

Abstract: An improved architecture for efficiently calculating a discrete wavelet transform is presented. The present system appreciates the associated redundancies of calculations and proposes a topology for eliminating such redundant calculations through the use of storing and making such previously calculated coefficients available in successive wavelet coefficient calculations. The present system while recognizing redundant calculations and performing storage operations, also provides a pipelined architecture whereby the wavelet coefficients are calculated and combined for use in a wavelet packet tree architecture.

Abstract: A circuit is provided for creating a termination impedance which matches a characteristic impedance. The characteristic impedance of a system or network is matched by placing a nominal impedance across the transmission line. The difference between the nominal impedance and the characteristic impedance is synthesized such that the synthesized or generated impedance is in parallel with the nominal impedance. The parallel combination of the nominal impedance and the generated impedance produces a termination impedance which substantially matches the characteristic impedance. The generated impedance is created by sensing a voltage and scaling that voltage by a factor related to the nominal and characteristic impedances. The scaled voltage controls a current source which produces a current having a value related to the inverse of the impedance. The ration of the sensed voltage and the generated current is the impedance which, when combined with the nominal impedance, produces the desired termination impedance.

Abstract: The present invention increases data transfer rate and reduces interrupt latency while avoiding a concomitant increase in interrupts to the host, by pacing the data flow between the UART and DSP using burst modes and wait modes.

Abstract: The high throughput UART to DSP interface (UDIF) maintains UART functionality while integrating dual Transmit (Tx) and Receive (Rx) FIFO buffers that are optimized for more efficient interaction with their respective I/O processors. The portion of the interface design interacting with the DSP, the UDIF, provides several unique Status, Informational, and Control registers that lower the DSP overhead required for many of the basic modem functions. The UDIF design also performs parity add, parity strip, and character echo functions, traditionally performed at a high overhead cost by the DSP. These functions are more efficiently preformed by hardware implementations than by the software routines executed by the DSP. More burdensome command functions like escape, AT, and flow control commands can also be implemented through hardware implementations to reduce processor overhead.

Abstract: Parallel data is serialized and transmitted and asynchronous data is received and placed into parallel bytes using a hardware assisted interface. The interface can be driven with very little overhead to the DSP. Additional timing registers and enhanced data buffers decrease the necessary DSP resource commitment. Furthermore the hardware settings in the interface can be adjusted by the DSP to optimize the interface's performance in transmitting various asynchronous protocols.

Abstract: In a system having an DSP, an ASIC and a memory, in which the ASIC generates a number of different competing interrupts for the DSP to service, the ASIC has an interrupt request control module which automatically provides the DSP with a vector pointing to the memory location of the interrupt service routine for the currently pending interrupt request having the highest priority of all pending requests. The DSP reads this vector and uses it to access the interrupt service routine in the memory. Reading of this vector causes the interrupt request to be de-asserted, which causes the next highest priority pending interrupt request to become the highest priority pending interrupt request. As a result, a new vector is presented for the next read by the DSP.

Abstract: A system and circuit is provided for digitally synthesizing the impedance of a transfer function. The impedance of the transfer function is digitally synthesized by generating a current that, when combined with an input voltage, results in the impedance of the transfer function. This is accomplished by sensing the input signal and processing it with a generator or multiplier such that a voltage is produced. The produced voltage controls a current source and creates a current having a value equal to the inverse of the transfer function impedance. The sensed or input voltage divided by the generated current is equal to the impedance of the transfer function. In this manner, many different transfer functions can be digitally synthesized without having to design an alternate circuit.

Abstract: The present invention relates to improved adaptive filtering techniques and architectures. Preferably, this filtering is performed as part of the digital processing that occurs with a digital signal processor. It is a feature of this invention that the adaptive filtering taught herein provides the advantages of both serial and parallel architectures, without the accompanying disadvantages thereof. In particular, an adaptive filter is taught that possesses low pin counts, fast processing times suitable for high-speed applications and reduced numbers of filter elements. In a preferred embodiment, the inputs and outputs of the adaptive filter are supplied to and from the adaptive filter in a serial manner while the processing is performed internally within the adaptive filter in a parallel manner.

Abstract: A method and apparatus for automatically switching between voice and data communications as directed by a voice and data capable modem via a cable assembly incorporating a switching means for facilitating and inhibiting the routing of voice information to a voice telephone. A voice and data capable modem incorporates the software functionality associated with a voice and data capable protocol with minimal impact to the form factor associated with the modem, To reduce the impact to the form factor associated with integrated modem designs, the switching hardware associated with voice and data capability is incorporated into a cable assembly used to interconnect the voice and data capable modem with the voice telephone. Additional means for identifying the cable assembly as having the requisite switching functionality is also provided.