Arbitrary Nonuniform Transmission Lines Research Articles

Fast and Efficient Analysis of Transmission Lines With Arbitrary Nonuniformities of Sub-Wavelength Scale

The Telegrapher's equations for a general nonuniform transmission line (NUTL) is analytically solved when the nonuniformities are of sub-wavelength scale. The proposed solution is based on an approximation of the chronological ordering operator for the Telegrapher's equations in an arbitrary NUTL. The proposed approximation is quite accurate when the transmission line has sub-wavelength nonuniformities. The scale of transmission line nonuniformity is assessed by using the concept of minimum resolvable length of nonuniformity (MRLN), which is based on the physically intuitive idea that electromagnetic waves are not affected by spectrally mild nonuniformities. The MRLN is inferred by using the spatial Fourier transform of the characteristics impedance of the NUTL. The proposed formulation is verified by using the measured scattering parameters of three different NUTLs.

Analytic solution of non-uniform transmission lines at low frequencies

A simple approximated analytical solution is introduced to analyse arbitrary non-uniform transmission lines (NTLs) at low frequencies. First, the differential equations of NTLs are written as a suitable matrix differential equation. Then, the matrix differential equation is solved to obtain the chain parameter matrix of NTLs. Later, the voltage and current of the line are obtained at any point using the obtained chain parameter matrix. Finally, the validation of the introduced solution is studied.

CLOSED FORM SOLUTIONS FOR NONUNIFORM TRANSMISSION LINES

In this paper, three analytic closed form solutions are introduced for arbitrary Nonuniform Transmission Lines (NTLs). The differential equations of NTLs are written in three suitable matrix equation forms, first. Then the matrix equations are solved to obtain the chain parameter matrix of NTLs. The obtained solutions are applicable to arbitrary lossy and dispersive NTLs. The validation of the proposed solutions is verified using some comprehensive examples.

Implementation of wave digital model in analysis of arbitrary nonuniform transmission lines

AbstractAn efficient method of analysis of nonuniform transmission lines (NTL), based on wave digital model composed of cascaded unit elements and two‐port adaptors, is described. The proposed technique treats NTL as a cascade connection of equal‐length or equal‐delay uniform transmission lines. A simple algorithm for calculating transmission and input reflection coefficients is derived. Two application examples, proving the efficiency and response accuracy of the new technique, are given. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 2150–2153, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22706

ANALYSIS OF NONUNIFORM TRANSMISSION LINES USING THE EQUIVALENT SOURCES

A new method is introduced to analyze arbitrary nonuniform transmission lines. In this method, the equations of nonuniform transmission lines are converted to the equations of uniform transmission lines, which have been excited by distributed equivalent sources. Then, the voltage and current distributions are obtained using an iterative method. The validity of the method is verified using a comprehensive example.

An efficient method for analysis of arbitrary nonuniform transmission lines

The analytical solution of an ideal linear varied nonuniform transmission line (LNTL) has been obtained and the exact linear two-port ABCD matrix of LNTL has been given correctly for the first time. By using cascaded LNTL sections to approximate an arbitrary characteristic impedance profile, a new technique has been presented in this paper for analyzing an arbitrary nonuniform transmission line (NTL). The technique is far better than the conventional technique in terms of the computational accuracy and intensity since it uses a piecewise-linear characteristic impedance profile in place of the stepped profile used by the conventional technique. Several numerical examples have been given to demonstrate the method.

Approximation of a nonuniform transmission line by a cascade of uniform lines

It is shown that an arbitrary nonuniform transmission line may be approximated by a cascade of commensurate uniform lines. In general, a small number of lines is sufficient to obtain a good approximation, and hence the method should prove useful, both in the analysis of arbitrarily tapered lines and in the study of their properties.