Cadence Design Systems, Inc.

Ansys, Inc.

Sas Ip, Inc.

New York University

Q Bio, Inc.

Jacob K White

Michael J Tsuk

Kenneth S Kundert

Ricardo Telichevesky

Athanasios Polymeridis

Daniel K Sodickson

Jeffrey Howard Kaditz

Deepak Ramaswamy

Luca Daniel

Jorge Fernandez Villena

J Eric Bracken

Amit Hochman

Riccardo Lattanzi

José E Cruz Serralles

Tze-Ting Fang

Keith Shelton Nabors

A plurality of stimulations is transmitted to tissue or other material using one or more transmitters. The plurality of signals associated with the excited tissue and the transmitted stimulations are measured. The measured signals are processed to generate field-related quantities, such as B1+ and/or MR signal maps. Field-related quantities are generated also from simulation, by calculating the one or more incident fields from a simulator model of the one or more transmitters and assuming a given distribution of electrical properties in the tissue or other material. Field-related quantities generated from simulation and experimental procedures are compared to each other. The assumed electrical properties distribution is updated and the procedure is repeated iteratively until the difference between simulated and experimental field-related quantities is smaller than a threshold.

Noninvasive determination of electrical properties of tissues and materials using magnetic resonance measurements

Systems and methods are provided for simulating an electrical characteristic of an electronic device having input ports and output ports. A device frequency response data structure is accessed that contains data associated with a plurality of port-to-port frequency responses of the electronic device, each port-to-port frequency response being associated with a plurality of frequencies. A QR decomposition is performed based on data from the frequency response data structure. A subset of the port-to-port frequency responses is selected based on the QR decomposition. A set of common poles is identified using the selected subset of port-to-port frequency responses, and a model of time domain behavior of the electronic device is generated using the set of common poles.

Systems and methods for parameter fitting and passivity enforcement for multi-port electronic devices

During operation, a system may apply a polarizing field and an excitation sequence to a sample. Then, the system may measure a signal associated with the sample for a time duration that is less than a magnitude of a relaxation time associated with the sample. Next, the system may calculate the relaxation time based on a difference between the measured signal and a predicted signal of the sample, where the predicted signal is based on a forward model, the polarizing field and the excitation sequence. After modifying at least one of the polarizing field and the excitation sequence, the aforementioned operations may be repeated until a magnitude of the difference is less than a convergence criterion. Note that the calculations may be performed concurrently with the measurements and may not involve performing a Fourier transform on the measured signal.

Rapid determination of a relaxation time

A model synthesizer generates a state-space model of a structure from frequency domain parameters of the structure using a selected number of significant eigenvalues of a matrix derived from the frequency-domain parameters such that the quality of the fit of the model is improved. A matrix of the frequency-domain parameters is reshaped so as to improve performance of determination of the fit quality. Passivity violations in the model can be removed via regularization and error control such that the fit quality of the model after removal of the passivity violations is within a specified tolerance. Cholesky factorization can improve the performance of passivity violation detection. This Abstract is provided for the sole purpose of complying with the Abstract requirement rules. This Abstract is submitted with the explicit understanding that it will not be used to interpret or to limit the scope or the meaning of the claims.

Enhancements to parameter fitting and passivity enforcement

Systems and methods are provided for constructing a physical transmission line system. Characteristic data associated with a transmission line system is received. A model of the transmission line system is built based on the characteristic data. Building a model of the transmission line system includes determining a characteristic admittance matrix based on the characteristic data, determining a propagation function matrix based on the characteristic data, calculating a linking matrix based on the characteristic admittance matrix and the propagation function matrix, and determining a state space model based on the characteristic admittance matrix and the linking matrix. A simulation is performed using the state space model to determine a physical characteristic, where the transmission line system is built or modified based on the simulation-determined physical characteristic.

Processor-implemented systems and methods for multi-conductor transmission line simulation

A simulator includes an analysis module for extracting a state-space model of response of a physical system to an input from a frequency-domain representation thereof, using a SVD, and singular vectors thereof, of a Loewner matrix derived from the frequency-domain representation, and a simulator module for simulating the response of the physical system in the time domain based on the extracted state-space model.

State-space model-based simulators and methods

An efficient method for determining the periodic steady state response of a circuit driven by a periodic signal, the method including the steps of 1) using a shooting method to form a non-linear system of equations for initial conditions of the circuit that directly result in the periodic steady state response; 2) solving the non-linear system via a Newton iterative method, where each iteration of the Newton method involves solution of a respective linear system of equations; and 3) for each iteration of the Newton method, solving the respective linear system of equations associated with the iteration of the Newton method via an iterative technique. The iterative technique may be a matrix-implicit application of a Krylov subspace technique, resulting in a computational cost that grows approximately in a linear fashion with the number of nodes in the circuit.

Method for determining the steady state behavior of a circuit using an iterative technique

Method for determining the steady state behavior of a circuit using an

A method and apparatus for making electrical circuits having RLCG lines is disclosed. The method depicts a circuit element taper of a selected element type as dependent upon an accumulated circuit element quantity. The method matches projections of the circuit element taper with projections of an approximate taper. The approximate taper depends upon the accumulated circuit element quantity. At least one reduced quantity for circuit element quantities of the selected element type is obtained on the computer. The one reduced quantity can be arranged in a reduced RLCG line having approximately the same performance as the RLCG line. The present invention should be particularly useful in verifying timing specifications and during the making of integrated circuits.

Method and apparatus for simulating an electrical circuit design using

An apparatus and method for improved efficiency of operation of a circuit simulator. The simulation engine processor sends signals via flag registers to the component model processors to indicate which type of response is required from each component model. The component model processors send back only the requested response, thus minimizing processing time by avoiding generating response types that are not needed. Flexibility is enhanced by centralizing tasks in the simulation engine rather than in the component models, in order to facilitate experimentation and variation in circuit configurations without extensive modifications of component model design.

Growing community of inventors

Belmont, MA, United States of America

Jacob K White