A frequency-symbolic method (FS-method) of the analysis of steady-state mode of linear parametric circuits is intended for forming their transfer functions in the frequency domain. Transfer functions are approximated by Fourier polynomials and contain a complex variable, time variable and parameters of circuit elements in the form of symbols. The coefficients of such Fourier polynomials by the FS-method are unknown in the symbolic systems of linear algebraic equations (SSLAE), and are defined as their solutions in symbolic form.

In the paper we present a method of forming an approximation expression which ensures the adequacy of calculations. Examples and results of computer experiments are given. The system of functions MAOPCs based on a frequency-symbolic method is used for the optimal design of electronic devices of noise-immune hidden radio engineering systems using code signals.

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