Improvements of Spectral Domain Analysis Techniques for Arbitrary Planar Circuits

Abstract

Spectral domain analysis techniques using roof-top functions as expansion functions for the surface current density have proofed to lead to a flexible tool for the calculation of arbitrarily shaped planar microwave structures. Several improvements of this method e.g. the introduction of new integration paths and analytic integration of a separated part of the dyadic function which reduce the computation time and which for the first time introduce losses (without using perturbation techniques) into the spectral domain analysis will be described. Furthermore the influence of surface waves and radiation is considered so that the transmission properties of planar microwave components can be described more realistically.

From static approximations to full‐wave analysis: The analysis of planar line discontinuities

“…Further improvements of the state of the art, as have been described in ref. 95. can be found as follows: a problem which leads to large computation time is the integration of the dyadic Green's function near the surface wave poles.…”

“…Rautio [82], for the first time, used these expansion functions for the analysis of a simple microstrip discontinuity (open end), and Wertgen and Jansen [87,88] developed it to a flexible design tool. This method and several improvements [95] shall be presented here subsequently.…”

Analytical evaluation of the asymptotic impedance matrix of a grounded dielectric slab with roof-top functions

“…The integrand of the first double integral in (15) possesses singularities corresponding to the surface wave poles. A number of techniques have been used to calculate these poles in the numerical integration such as a pole extraction technique [3], [11], a method of deformed integration contour [12], and a folding technique [13]. In this paper, these poles are evaluated with the use of a folding technique.…”

Calculation of Three-Dimensional Passive Structures Including Bond-Wires, Via-Holes and Air-Bridges using the Spectral Domain Analysis Method

“…The whole three-dimensional structure can be considered as a superposition of different two-dimensional structures. The numerical effort to calculate the Z-matrix elements can be reduced by extensive use of FFT-algorithm in connection with the residue theory in order to include surface wave effects and effects due to radiation, both described in [5]. Especially for complex problems the matrix-fill-time becomes small compared to the time required for the solution of the resulting matrix equation.…”

“…These full-wave analysis methods using roof-top functions as expansion functions for the surface current density have proofed to be flexible tools for the calculation of arbitrary shaped planar passive microwave structures. Due to the implementation of FFT-algorithm and iterative methods, efficient S-parameter calculations of complex planar circuits have become possible [5]. Spectral domain analysis can take into account effects of multilayer structures as well as losses due to surface waves, radiation and non-ideal strip and backside metallization (if existing).…”