In recent years, the necessity for fast, accurate and less memory-intensive techniques to analyze nonlinear circuits has grown as technology has advanced. The harmonic balance (HB) method is a powerful tool and it has been used for some time in nonlinear circuit analysis. In order to keep up with the vast requirements of circuit design, the harmonic balance method is modified to make it fast, more accurate and require less memory.; In the modified harmonic balance (MHB) method, circuits are analyzed by calculating voltages and currents of nonlinear components in the time domain and those of linear components in the frequency domain. After that, an iteration scheme is performed in which the voltage and current values have to be transformed from one domain to the other for each single iteration. A key point to reduce the analysis time and minimize the memory required is to use an efficient way to transform from one domain to another, taking into account multi-tone circuits, and to handle the set of voltage and current values in a simple matter. One-dimensional Fourier transformations are used to convert from the time domain to the frequency domain and visa versa. The current and voltage values are handled using a vector matrix for each nonlinear element instead of using Jacobian matrices.; The harmonic balance technique can sometimes be deceiving, especially when it converges to the wrong solution. To achieve convergence to the correct solution, the initial values must be chosen with great care. The fundamental-frequency solution, obtained using experimental results or numerical analysis, is used as an initial estimate. This initial estimate will assure accurate results. To minimize errors, two two-port networks are performed since they are simple and straight forward.; Solutions obtained using MHB code written in MATLAB were compared with P-Spice results. The results show good accuracy.
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