Numerical calibration techniques and applications of planar integrated microwave structures

In this work, a set of numerical thru-reflect-line (TRL) and thru-resistor (TR) calibration techniques are proposed and combined with commercial planar electromagnetic (EM) simulation software. Such numerical calibration techniques are used to eliminate port discontinuities brought by the lumped current/voltage exciting sources in a deterministic method-of-moments (MoM) algorithm. Therefore, accurate equivalent full-wave-based circuit models of the planar discontinuities can be extracted and established for CAD and optimization purposes.;With the help of a numerical calibration technique, field-based equivalent circuit models of the port discontinuities are rigorously extracted. Generally, the circuit model of a port discontinuity can be represented by a shunt capacitor and a series inductor. Values of those elements in the circuit model might unfortunately be different when different exciting schemes are applied. From the analysis that is based on a transformation from S parameters to Z or Y parameters, we can observe that a small port discontinuity change can generate huge errors in the extracted equivalent circuit elements of planar circuits and this verily confirms that the calibration is absolutely necessary to remove the errors. (Abstract shortened by UMI.).;The TRL calibration makes use of three standards, namely, through, reflect and line connections. The TRL calibration standards are easy to realize in both practical circuit measurements and numerical EM simulations. The error boxes, which consist of the port discontinuity effects and guided (or feed) line sections from the exciting source planes to DUT (device-under-test), can be set up by using these standards. Then, accurate parameters that electrically characterize the DUT can be obtained. In a TRL calibration procedure, the characteristic impedance of the line standard should be known exactly a priori. To obtain this characteristic impedance for the TRL calibration, a resistor standard is introduced in this work as impedance reference for extracting a three-dimensional (3D) characteristic impedance of the line standard. Generally, the numerical TRL calibration is bandwidth-limited and it is difficult to extend to a scenario of multiport calibration. To remedy this situation, we have proposed numerical 2-port TR and multi-parallel port TR calibration techniques. The 2-port TR calibration procedure deploys through and resistor standards while the multi-parallel port TR calibration uses through, match and multi-resistors standards. Comparing results obtained from our proposed numerical calibration techniques with published results as well as the static modeling results has validated the proposed numerical calibration techniques.