Patents Assigned to National Instruments Corporation
  • Patent number: 10467059
    Abstract: A method for determining timing constraints in dataflow models is disclosed. The method includes receiving node information specifying a plurality of dataflow nodes, as well as coupling between various ones of the dataflow nodes. The method further comprising receiving timing information specifying timing constraints for at least some of the dataflow nodes. Based on the node information, the couplings between the nodes, and the timing information, a timeline dependency graph (TDG). The timeline dependency graph illustrates a timeline, mappings between nodes with side effects to firing times of those nodes on the timeline, and dependencies between nodes.
    Type: Grant
    Filed: March 28, 2017
    Date of Patent: November 5, 2019
    Assignee: National Instruments Corporation
    Inventors: Patricia Derler, Kaushik Ravindran, Hugo A. Andrade, Ankita Prasad, Arkadeb Ghosal, Trung N. Tran, Rhishikesh Limaye, Jacob Kornerup
  • Patent number: 10447513
    Abstract: A wireless device receives a frequency division multiplexed (FDM) symbol of constituent equalized FDM data subcarriers. A modulation scheme constellation diagram is subdivided into two or more regions. For each of the regions, a subset of the subcarriers that fall within the region are extracted and a respective region-specific CPE estimate is computed thereon. The respective region-specific CPE estimates are averaged to produce an overall CPE estimate used to compensate the subcarriers. Furthermore, a first CPE estimate is computed using pilot symbols embedded in a first received FDM symbol and is used to compensate the subcarriers. A following second FDM symbol that has no embedded pilot symbols is compensated using the first CPE estimate, and a second CPE estimate is computed using a blind estimation method on the second FDM symbol compensated subcarriers, which are compensated using the second CPE estimate.
    Type: Grant
    Filed: December 27, 2017
    Date of Patent: October 15, 2019
    Assignee: National Instruments Corporation
    Inventors: Nikhil U. Kundargi, Achim Nahler
  • Patent number: 10447352
    Abstract: A wireless cellular base station (BS) transmitter transmits a downlink calibration pilot symbol. A receiver receives from a user equipment (UE) an uplink calibration pilot symbol and an effective downlink channel estimate transmitted by the UE. The effective downlink channel estimate is computed by the UE using the downlink calibration pilot symbol received from the BS. Processing devices compute an effective uplink channel estimate using the uplink calibration pilot symbol received from the UE and compute channel reciprocity calibration coefficients using the effective downlink channel estimate received from the UE and the effective uplink channel estimate computed by the BS. The BS includes multiple antennas, and the BS computes the channel reciprocity calibration coefficients for each antenna. Alternatively, the uplink channel estimate received by the BS is an inverted version of the effective downlink channel estimate, which the processing devices use for channel reciprocity compensation.
    Type: Grant
    Filed: August 10, 2017
    Date of Patent: October 15, 2019
    Assignee: National Instruments Corporation
    Inventors: Nikhil U. Kundargi, Karl F. Nieman, Junmo Sung
  • Patent number: 10436874
    Abstract: Systems and methods for calibration and operation of a source-measure unit (SMU). The system may include a functional unit and output terminals coupled to the functional unit. An excitation signal may be applied to a capacitor by the SMU. The capacitor may be included in a calibration circuit. The method may include obtaining one or more of a current calibration coefficient (CCC) or a voltage calibration coefficient (VCC). The CCC may correspond to a current-range setting and the VCC may correspond to a voltage-range setting. The CCC may be obtained from a value of a first current and a value of a second current developed in the capacitor responsive to the excitation signal. The VCC may be obtained from a value of a first voltage and a value of a second voltage developed across the capacitor responsive to the excitation signal.
    Type: Grant
    Filed: January 8, 2019
    Date of Patent: October 8, 2019
    Assignee: National Instruments Corporation
    Inventors: Christopher G. Regier, Pablo Limon
  • Patent number: 10394643
    Abstract: System and method for auto-calculating uncertainty of a measurement performed by a measurement device. The measurement device initiates a measurement or measurements. In response to the measurement initiation, a driver of the measurement device sends an error specification request to each of a plurality of hardware modules involved in the measurement. Each of the plurality of hardware modules determines the requested error specifications based on a current configuration of the respective hardware module. The measurement device then calculates an uncertainty associated with the measurement or measurements based on the error specifications.
    Type: Grant
    Filed: August 16, 2017
    Date of Patent: August 27, 2019
    Assignee: National Instruments Corporation
    Inventor: Robert W. Hamner
  • Patent number: 10396867
    Abstract: A method for reducing complexity of downlink signal demodulation in a multiuser (MU) multiple-input-multiple-output (MIMO) wireless communication system includes a base station acquiring uplink (UL) channel state information (CSI) of a MIMO channel between the base station and a user equipment (UE), deriving downlink (DL) CSI from the UL CSI, and transmitting orthogonal frequency-division multiplexing (OFDM) radio subframes using MIMO pre-equalization based on the DL CSI. The UE performs downlink reciprocity correction of the OFDM subframes received from the base station using a single complex phasor estimate and performs downlink data demodulation of the downlink reciprocity corrected OFDM subframes without performing additional MIMO equalization.
    Type: Grant
    Filed: October 30, 2017
    Date of Patent: August 27, 2019
    Assignee: National Instruments Corporation
    Inventors: Nikhil U. Kundargi, Karl F. Nieman
  • Patent number: 10371733
    Abstract: The noise figure for a radio frequency device may be obtained through power measurements. A signal flow graph based upon the S-parameter information of the entire RF system may be constructed. The S-parameter information may be representative of the microwave termination, the device, the measurement instrument and any losses due to additional components such as connecting cables/attenuators/switches, etc. The signal flow graph includes proper placement and values of the source nodes corresponding to each RF sub-system enumerated above. Noise figure measurements may include a calibration step and a measurement step. During the calibration step the noise figure and the noise temperature of the measurement instrument used for the measurement may be obtained. During the measurement step, the noise figure and the noise temperature of the device may be obtained based at least on the noise figure and noise temperature of the measurement instrument obtained during the calibration step.
    Type: Grant
    Filed: January 4, 2017
    Date of Patent: August 6, 2019
    Assignee: National Instruments Corporation
    Inventors: Prabhat Pal, Vinay Kumar Velkuru, Brian J. Avenell
  • Patent number: 10374456
    Abstract: An embedded system may distribute, e.g. at the point of coupling to a main power grid, information corresponding to one or more operational parameters (e.g. phase angle, frequency, amplitude, etc.) of a power delivery device to other power delivery devices, using a deterministic communication link. Updates of some or all of the information may be transmitted at future or past points in time, for example at defined time intervals. Time synchronization methods, e.g. a locked instantaneous interpolation mechanism may be used to create a coordinated time, shared among all power delivery devices. Various operating parameter mismatches, e.g. a phase mismatch between power delivery devices delivering power to the power grid, may thereby be reduced to less than a specified, negligible value. This creates tight time synchronization between the power delivery devices and allows them to interoperate in a manner that stabilizes rather than destabilizes the power grid.
    Type: Grant
    Filed: September 26, 2017
    Date of Patent: August 6, 2019
    Assignee: National Instruments Corporation
    Inventors: Brian C. MacCleery, Todd J. Walter, Burt D. Snover
  • Patent number: 10367525
    Abstract: Techniques are disclosed relating to encoding communications. In some embodiments, for different rows of an encoding matrix, the following operations are performed: generate a set of operations for entries in the row, where the set of operations includes respective operations to be performed on the entries for multiplication of the matrix by a vector, propagate values of entries in the encoding matrix into the set of operations, and simplify ones of the set of operations based on the propagated values to generate an output set of operations. In some embodiments, the output sets of operations are usable to encode input data for communication over a medium. In some embodiments, the disclosed techniques facilitate loop unrolling within compiler memory constraints. In some embodiments, an apparatus (e.g., a mobile device) is configured with the output sets of operations.
    Type: Grant
    Filed: May 29, 2015
    Date of Patent: July 30, 2019
    Assignee: National Instruments Corporation
    Inventors: David C. Uliana, Newton G. Petersen, Tai A. Ly, Hojin Kee, Adam T. Arnesen, Dustyn K. Blasig, Gandiinaa Gumenjav
  • Patent number: 10338110
    Abstract: A source-measure unit (SMU) may be implemented with digital control loops and circuitry to digitally compensate for the impact of input bias current on current measurements. One or more buffers having well-defined characteristics with respect to certain parameters which may affect the current measurements may be used in the output signal path of the SMU where a shunt voltage developed across a current sense element is measured. For example, the buffers may conduct/develop respective input bias currents that change perceptibly and predictably with temperature. By measuring the temperature and adjusting a control voltage—which is used to develop the shunt voltage—according to the temperature measurements, the impact of the input bias current[s] on the current measurement[s] may be reduced to negligible levels and/or may be eliminated.
    Type: Grant
    Filed: November 22, 2016
    Date of Patent: July 2, 2019
    Assignee: National Instruments Corporation
    Inventors: Pablo E. Limon-Garcia-Viesca, Christopher G. Regier
  • Patent number: 10331361
    Abstract: Techniques are disclosed relating to self-addressing memory. In one embodiment, an apparatus includes a memory and addressing circuitry coupled to or comprised in the memory. In this embodiment, the addressing circuitry is configured to receive memory access requests corresponding to a specified sequence of memory accesses. In this embodiment, the memory access requests do not include address information. In this embodiment, the addressing circuitry is further configured to assign addresses to the memory access requests for the specified sequence of memory accesses. In some embodiments, the apparatus is configured to perform the memory access requests using the assigned addresses.
    Type: Grant
    Filed: January 3, 2017
    Date of Patent: June 25, 2019
    Assignee: National Instruments Corporation
    Inventors: Tai A. Ly, Swapnil D. Mhaske, Hojin Kee, Adam T. Arnesen, David C. Uliana, Newton G. Petersen
  • Patent number: 10312978
    Abstract: In a wireless transceiver station having M antennas, designate an antenna as a target reference antenna (TRA) and for each antenna m other than the TRA: define N distinct paths from antenna m to TRA through zero or more intermediate reference antennas, N is two or more, each distinct paths has a distinct associated set of one or more antenna pairs; for each antenna pair of the sets, estimate an effective forward and backward channel response by sending calibration pilots forth and back between the antenna pair and calculate a reciprocity coefficient for the antenna pair using the estimated channel responses; for each of the N distinct paths, calculate a reciprocity coefficient estimate using the reciprocity coefficients calculated for the set of antenna pairs associated with the path; and combine the N calculated reciprocity coefficient estimates to produce a final reciprocity coefficient estimate for antenna pair (m, target reference antenna).
    Type: Grant
    Filed: July 16, 2018
    Date of Patent: June 4, 2019
    Assignee: National Instruments Corporation
    Inventors: Jörg Hofrichter, Michael Löhning, Eckhard Ohlmer
  • Patent number: 10277734
    Abstract: An apparatus includes a cellular frequency radio, either coupled to or configured to be coupled to an antenna disposed within a radio frequency (RF) shielded chamber. A cellular device includes an embedded subscriber identification module (eSIM). While the device is in the shielded chamber, a processor controls the radio to use the antenna to transmit a subscriber identification module (SIM) profile to the device and subsequently communicate with the device to test operation of the device while the device uses the SIM profile loaded into the eSIM. A cellular device includes an eSIM without a SIM profile, a cellular frequency radio, and a processor that controls the radio to wirelessly receive a SIM profile while the eSIM is still without a SIM profile, loads the received SIM profile into the eSIM, and controls the radio to wirelessly communicate with a cellular network using the SIM profile loaded into the eSIM.
    Type: Grant
    Filed: August 21, 2017
    Date of Patent: April 30, 2019
    Assignee: National Instruments Corporation
    Inventor: Tim Hentschel
  • Patent number: 10257329
    Abstract: A wireless communications apparatus includes first/second data source/sinks that respectively source/sink PDCP SDU and MAC PDU for transfer to/from a memory unit and hardware accelerators controlled by a control processor (CP). In response to sourcing transmit PDCP SDU for transfer to the memory unit, the CP controls the hardware accelerators to generate and write PDCP, RLC, MAC headers to the memory unit and assemble the generated headers and the transmit PDCP SDU from the memory unit into transmit MAC PDU for provision to the second data sink. In response to sourcing receive MAC PDU for transfer to the memory unit, the CP controls the hardware accelerators to decode PDCP, RLC MAC headers of the receive MAC PDU in the memory unit to determine locations of receive PDCP SDU in the memory unit and fetch the receive PDCP SDU from the determined locations for provision to the first data sink.
    Type: Grant
    Filed: September 8, 2017
    Date of Patent: April 9, 2019
    Assignee: National Instruments Corporation
    Inventors: Ahsan Aziz, Amal Ekbal, Vincent Kotzsch
  • Patent number: 10257005
    Abstract: An apparatus includes circuitry that processes a subframe as part of a time-domain signal frame structure used for radio frequency communications. The subframe includes a plurality of block symbols each having an associated time-domain guard period and one or more radio frequency (RF) switching guard periods. Each block symbol of the plurality of block symbols is either a common block symbol or a special block symbol. A common block symbol has a common time-domain guard period with all other common block symbols of the subframe. A special block symbol has a time-domain guard period different from the common time-domain guard period. All the special block symbols in the subframe are placed into the one or more RF switching guard periods.
    Type: Grant
    Filed: August 10, 2017
    Date of Patent: April 9, 2019
    Assignee: National Instruments Corporation
    Inventors: Michael Löhning, Achim Nahler, Nikhil Kundargi
  • Patent number: 10243715
    Abstract: Embodiments are disclosed for a new unified and flexible frame structure for 5G (5th generation) mobile telecommunications standard and related radio access technology (RAT). The disclosed embodiments use communication frames with multiple partition types and are able to span a wide range of 5G deployment scenarios in a flexible and scalable manner.
    Type: Grant
    Filed: September 20, 2016
    Date of Patent: March 26, 2019
    Assignee: National Instruments Corporation
    Inventors: James Wesley McCoy, Nikhil U. Kundargi, Karl F. Nieman
  • Patent number: 10241764
    Abstract: System and method for compiling a program, including determining one or more program structures containing one or more variables at the entry and exit of each program structure, wherein each variable specifies a value transfer operation of one or more source variables to a destination variable between outside the program structure and inside the program structure. A subset of the destination variables may be determined for which assigning the destination variable to a memory resource of a corresponding source variable does not disrupt the functionality of the program. Implementation of the value transfer operations may be executable to map each of the determined subset of destination variables to a respective memory resource. The mapping may be dynamically changed, thereby transferring the value from the first source variable to the destination variable without copying the value between the memory resources.
    Type: Grant
    Filed: May 5, 2017
    Date of Patent: March 26, 2019
    Assignee: National Instruments Corporation
    Inventors: Hojin Kee, David C. Uliana, Tai A. Ly, Adam T. Arnesen
  • Patent number: 10243678
    Abstract: Dynamic characterization of complex high-order nonlinearity in transmitter (TX) and receiver (RX) signal chains of transceiver systems can be efficiently and accurately performed. A loopback connection may be used to facilitate self-characterization. Appropriate RX and TX configuration settings may be developed to facilitate de-coupling of individual RX and TX nonlinearities from measured cascade nonlinearity. The system's high-order response to a two-tone signal generation may be measured, and complex mathematical analysis may be performed to identify and isolate passband nonlinear components to extract a high-order memory-less model for the system. The extracted system model may be used in the corrective and non-iterative pre-distortion of generated signals and in the post-distortion of received signals to improve linearity performance of the transceiver.
    Type: Grant
    Filed: July 11, 2014
    Date of Patent: March 26, 2019
    Assignee: National Instruments Corporation
    Inventors: Mohamad A. Zeidan, Christopher J. Behnke, Syed Jaffar Shah
  • Patent number: 10235265
    Abstract: System and method for validating a program under a specified model of computation. The model of computation may be related to the synchronous statechart model of computation. A program may be received that specifies a plurality of operations using a variable within a logical tick such that the variable has multiple values within the logical tick. The program may be statically analyzed according to a specified model of computation that specifies program execution based on logical ticks, which may include determining that the program has deterministic semantics that specify deterministic results for each logical tick during execution of the program, including specifying deterministic results of the plurality of operations performed within the logical tick. The program may be validated in accordance with the specified model of computation in response to the determining.
    Type: Grant
    Filed: December 18, 2015
    Date of Patent: March 19, 2019
    Assignee: National Instruments Corporation
    Inventors: Reinhard von Hanxleden, Michael Mendler, Stephen R. Mercer, Owen B. O'Brien
  • Patent number: 10235868
    Abstract: System and method for controlling a custom modular measurement system. An editor may receive user input specifying one or more system definitions, each mapping message based commands, parameters, variables and/or metadata (“information”) accordant with a control protocol for standalone instruments to functions and data in a programming language, and generates the definitions accordingly, each being useable by a client application to interface with a custom modular measurement system that includes multiple logical instruments via the message based information. At least one of the definitions may be deployed onto the measurement system. A run-time engine of the measurement system may accept a message based command from the application, and call a corresponding function, which may invoke operation of at least one of the logical instruments. The logical instruments may be operated concurrently, including sharing use of a single physical measurement device by at least two of the logical instruments.
    Type: Grant
    Filed: September 29, 2014
    Date of Patent: March 19, 2019
    Assignee: National Instruments Corporation
    Inventors: Richard Henry Mace Keene, Jan Viborg Moeller