In COPLAN for ADS the characteristics of coplanar elements are calculated using quasi static equivalent circuits. The circuit parameters are derived from a three dimensional Finite Difference calculation. In a so called pre analysis, these equivalent parameters are calculated and stored in a cache. For the analysis of the circuit, only the Y or Z or S parameters are then calculated over the frequency and can be plotted within the ADS.
In some cases, the user need to know more about the pre analysis of each element involved in the circuit. In order to get information about the calculated equivalent circuit parameters, the user can utilize the coplanar debugger element C_DEBUG which is implemented in to COPLAN for ADS. Using C_DEBUG element, the static and dynamic output parameters of each element in the circuit design can be written out in an output file in ASCII format. This tool was developed initially for the bug fixing of the software and if not free of bugs. Furthermore, there are a lot of data in the output file which are not interesting to the normal user.
One interesting application example is the characteristics of coplanar lines. If C_DEBUG is put in the schematic window of a single coplanar line, the characteristic impedance ZL, the effective dielectric constant as well as the attenuation of the coplanar line are written in a file (in ASCII format) which can be specified in C_DEBUG. This could be important, if the user likes to know more about the propagation characteristics of involved transmission lines.
The static output parameters of the 3D elements can also be used in order to check the accuracy of the simulation. The comparison between the characteristic impedance (or effective dielectric constant) of the connected lines (C_FEED) and those calculated by the element itself is an indicator for the influence of the magnetic walls on calculated results. The relative deviation of these two values from each other should be let than %5.
The coplanar debugger in COPLAN for ADS can be accessed by selecting the palette „IMST Utilities“ in the schematic window. Presently, there is only one element, C_DEBUG in these palette. The use of this element is described in the next pages.