Patent ID: 6775646
Filing Date: 2004-08-10
Classification: G01R,G06F,G06K

Abstract:
A method of producing a behavioral model of a nonlinear device from embeddings of time-domain measurements, the device being real or virtual and having one or more input ports and one or more output ports, the method comprising:applying an input signal to the input port of the nonlinear device; sampling the input signal to produce input data; measuring a response to the input signal at the output port of the device to produce output data corresponding to the input data; creating an embedded data set using a first subset of the input data and a first subset of the output data; fitting a function to the embedded data set; and verifying the fitted function using a second subset of the input data and a second subset of the output data, such that the verified fitted function is the behavioral model of the nonlinear device, wherein applying an input signal comprises constructing a CDMA type signal u(t) as the input signal, the CDMA type signal being given by u&it;â€ƒ&it;(t)=A&it;â€ƒ&it;cos&it;â€ƒ&it;(2&it;â€ƒ&it;Ï€&it;â€ƒ&it;fc&it;â€ƒ&it;t)&it;â€ƒ&it;&Sum;i=1N&it;â€ƒ&it;bi&it;â€ƒ&it;(t)&it;â€ƒ&it;piâ€ƒwhere fc is a center frequency, bi(t) are random vectors, pi are coefficients of a bandpass finite impulse response (FIR) filter, N is a vector dimension expressed as an integer, and A is a constant amplitude value, the constructed CDMA type input signal being applied to the input port of the nonlinear device.