Quad-band matching network design with real frequency technique employing frequency transformation

In this study, a piecewise frequency transformation is presented for quad-band (QB) matching network design. The real frequency direct computational technique RFDCT is incorporated with the generated QB transformation. The proposed approach employs three sequential application of low-pass (LP) to band pass (BP) transformation. Transformation parameters are derived by using a direct LP to QB mapping scheme. RFDCT is used to find the optimum element values of a pre-defined transformer free matching network topology within a nonlinear iteration routine which incorporates the QB transformation. For assigned quad pass-bands, the parameters of QB transformation are also optimized to improve transducer power gain (TPG) of the matching network. A quad-band matching network design example is given to illustrate application of the proposed method.