Abstract: A parallel processing designing device includes: an observation point computing section that, in a case in which an order of plural design variables exceeds a predetermined order, eliminates a design variable that has a low contribution to designing, and for each of plural design variables that are less than or equal to the predetermined order, computes plural observation points for searching for a region in which a performance relating to the design variable is executable, by using an acquisition function and a penalty function; a probability distribution computing section that, for each of the plural performances, computes a probability distribution of the performance being executable at the computed plural observation points; and a multiple performance executable region outputting section that outputs, as a multiple performance executable region, an infinite product of the probability distributions that are respectively computed for the plural performances.

Abstract: In order to generate a broadband transfer function of complex characteristics of a linear time-invariant (LTI) system, data characterising properties of the system are acquired. A set of poles in the complex plane are defined to characterize the system, and then an iterative process is performed to: define a set of orthonormal rational basis functions incorporating the defined poles, use the orthonormal rational basis functions to estimate transfer function coefficients, and derive revised values for the complex poles, until a desired level of accuracy of the transfer function coefficients is attained. The revised complex poles are used to determine parameters of the broadband transfer function.

Abstract: A linear time-invariant system modeling apparatus comprises a processing resource arranged to receive, when in use, model data constituting to a model of a linear time-invariant system. The model data includes residual value data and scattering data. The processing resource is arranged to perform, when in use, a single value decomposition in respect of the scattering data; the scattering data corresponds, when expressed in matrix form, to a scattering matrix in a state-space representation of the model. The processing resource is also arranged to use, when in use, a result of the single value decomposition in order to generate residual value modification data. The residual value modification data is applied to the residual value data, the residual value data corresponding, when expressed in the matrix form, to a residual value matrix in the state-space representation of the model.

Abstract: The present invention relates to a method (200) for generating a multivariate system model of a multivariate system which has a plurality of parameters and the multivariate system model is representative for the system response to changes in the parameters. The method (200) involves performing a plurality of measurements and/or simulations on the multivariate system to obtain reference data (201). The method further involves the selection of rational base functions (202) and combining these base functions (203) into a model of the multivariate system. The multivariate system model is obtained (208) by minimizing a cost function (205) between the model and the reference data. Explicit weight factors which are related to the reference data are used. The respective values for the explicit weight factors in the cost function are iteratively determined (205) in order to approximate the reference data with the model and the cost function is updated accordingly in each iteration.

Abstract: A linear time-invariant system modeling apparatus comprises a processing resource arranged to receive, when in use, model data constituting to a model of a linear time-invariant system. The model data includes residual value data and scattering data. The processing resource is arranged to perform, when in use, a single value decomposition in respect of the scattering data; the scattering data corresponds, when expressed in matrix form, to a scattering matrix in a state-space representation of the model. The processing resource is also arranged to use, when in use, a result of the single value decomposition in order to generate residual value modification data. The residual value modification data is applied to the residual value data, the residual value data corresponding, when expressed in the matrix form, to a residual value matrix in the state-space representation of the model.

Abstract: In order to generate a broadband transfer function of complex characteristics of a linear time-invariant (LTI) system, data characterising properties of the system are acquired. A set of poles in the complex plane are defined to characterise the system, and then an iterative process is performed to: define a set of orthonormal rational basis functions incorporating the defined poles, use the orthonormal rational basis functions to estimate transfer function coefficients, and derive revised values for the complex poles, until a desired level of accuracy of the transfer function coefficients is attained. The revised complex poles are used to determine parameters of the broadband transfer function.

Abstract: A method of concatenating a plurality of narrowband frequency-domain models of a linear time-invariant (LTI) system, each model being descriptive of the system's operational characteristics over a different respective frequency range, to derive a single broadband model that describes the system's operational characteristics over the total frequency range encompassed by the narrowband models, includes assembling stable poles of matrix representations of the narrowband frequency-domain models together with additional poles satisfying a predetermined criterion, based on band-limited truncated Complete Orthonormal Kautz Bases (COKB) requirements, to derive a canonical modal system matrix, deriving a band-limited controllability Grammian as a function of the canonical modal system matrix.

Abstract: A method for modeling a general passive interconnection structure for use in a circuit simulator. The model is based on full-wave EM simulations and has a predefined accuracy when compared to the full-wave EM simulator. The interconnection structure is described by parameters that depend on geometric parameters determined by a vector x and the frequency of the signal passing through the interconnect circuit. In a CAD system according to the present invention, information representing a plurality of coefficients, Cm(f) is stored in the CAD system for m=0 to M. The CAD system also stores information specifying the values of a plurality of multinomial functions, Pm(x) for m=0 to M, wherein M>1.