NONUNIFORM TRANSMISSION LINES AS COMPACT UNIFORM TRANSMISSION LINES

In this paper, we propose a new way to compact the transmission lines, which has a general application to miniaturization of RF and microwave circuits. In this way, we use Nonuniform Transmission Lines (NTLs) instead of Uniform Transmission Lines (UTLs). To synthesize the desired Compact Length Transmission Lines (CLTLs), the characteristic impedance function of the NTLs is expanded in a truncated Fourier series. Then, the optimum values of the coefficients of the series are obtained through an optimization approach. The usefulness of the proposed structures is verified using some examples.