Optenni Lab — Component library
Optenni Lab includes an easy-to-use component library of commonly used inductors and capacitors that supports automatic matching circuit generation and sensitivity analysis. Currently more than 100 component series from 6 major manufacturers (AVX, Coilcraft, Johanson, Murata, Taiyo Yuden and TDK) are included in the library.
Setting up the library is easy: you can download and install your favorite component series directly from Optenni Lab GUI, after which the component series can be selected for automatic synthesis or manual topology optimization. In the optimization, Optenni Lab takes into account losses and parasitic effects of the components, and selects the best performing combination of the available discrete component values.
The component libraries also contains tolerance data so that you can carry out statistical analysis of the circuit performance due to the component tolerances, and also rank the topologies according to the performance sensitivity.
Two-way link with CST STUDIO SUITE®
Launching Optenni Lab from CST STUDIO SUITE
Customers who have both CST STUDIO SUITE® and Optenni Lab licenses can easily construct matching circuits in Optenni Lab using the impedance and radiation pattern data calculated in CST STUDIO SUITE and return the optimized matching circuits back to CST DESIGN STUDIO™. In short, the procedure is as follows:
- In CST MICROWAVE STUDIO® use the command "Home->Macros->Matching Circuits->Launch Optenni Lab" to launch Optenni Lab using the simulated impedance and radiation pattern data.
- Synthesize the circuits in Optenni Lab, and right click any of the generated circuits and select "Transfer circuit to CST DESIGN STUDIO" whereafter the circuit is constructed on the CST DESIGN STUDIO schematic, connected to external ports and simulated.
Post-processing templates for parameter sweeps and optimization in CST MICROWAVE STUDIO
In addition, CST MICROWAVE STUDIO's template based post-processing tools can be used to automatically apply Optenni Lab within a parameter sweep or an optimization task in CST MICROWAVE STUDIO. Thus, a combined electromagnetic and circuit optimization task can easily be defined, where the typical goal is to design an antenna or antenna system such that the total efficiency is maximized, using a realistic matching circuit with available off-the-shelf discrete component models.
Video presentation of the link:
Optenni Lab — List of main features
The main features of the Optenni Lab circuit synthesis software are:
- Capability of reading multiport S parameter files of the load (antenna) impedance in the Touchstone format (S or Z parameters)
- Specification of complex frequency-dependent termination impedance for each port
- De-embedding the effect of a measurement cable
- Automatic generation of matching circuit topologies and optimization of component values
- Preset frequency range data for many wireless systems (GSM, WCDMA, TD-SCDMA, 3GPPP bands, WLAN, BT, navigation etc.)
- Component library of commonly used inductors and capacitors
- Tolerance analysis of the generated matching circuits
- Simultaneous multiport matching
- Modeling of component losses and optimization of the transducer power gain or the impedance match of the matching circuits
- Optimization of matching circuits where the topology and some component values have been fixed using inductors, capacitors, resistors, transmission lines, S parameter blocks
- Support for tunable S parameter blocks in the S2PMDIF data format, indexed by one or multiple variables
- Specification of complex matching circuit topologies including series and parallel resonators
- Specification of different optimization targets for different frequency bands and specification of stop bands
- Plotting the two-port S parameters of the matching circuit and together with mismatch loss, component losses and total efficiency through the matching circuit
- Interactive tuning of the matching circuits
- Generation of matching circuits that obtain conjugate matching to the termination impedance or maximize the bandwidth around a starting frequency
- Visualizing the impedance trace of a matching circuit at a single frequency on the Smith chart
- Calculation of the system S parameters when one of the ports has been terminated with a matching circuit
- Saving system S parameters, matching circuit S parameters and input impedances as Touchstone files
- Saving plots in various file formats (.jpg, .bmp, .tiff, .png, .pdf, .ps) and saving plot data as text files
- Estimation of the obtainable impedance bandwidth through matching circuits using the bandwidth potential and Q value techniques
- Estimation of the obtainable efficiency bandwidth through matching circuits with a predefined topology and tunable components
- Calculation of the antenna radiation efficiency from the total efficiency and impedance data
- Calculation of the electromagnetic isolation (worst-case isolation) between two ports of a multiport system
- Capability to save and load project files containing the previously computed results
- An easy-to-use graphical user interface where all the previously computed results are available in a result tree
- A two-way link with CST STUDIO SUITE™
- A link to Microwave Office™
- On-line manual
Optenni Lab — Visualizing impedance trace
The impedance trace feature visualizes how the components of a matching circuit transform the originial impedance to the input impedance at one frequency. The visualization shows how series components rotate the impedance along the constant resistance circles of the Smith chart and parallel components rotate the admittance along the constant conductance circles.
Consider the pictures below showing a three-component matching circuit, the S-parameters through the matching circuit and the corresponding Smith chart plot showing the original impedance, impedance through the matching circuit, impedance trace and also the admittance chart.
The Smith chart plot shows at the selected frequency (1.922 GHz) how the parallel (red lines) and series (black lines) components move the impedance from the original impedance curve (violet curve, circle marker) to the input impedance (blue curve, cross marker).
The impedance trace feature is very instructive as it shows how the different components affect the impedance. You can gain more insight into the operation of the matching circuit by changing the frequency where the trace is calculated (by dragging the vertical dashed line on the S parameter plot) or by tuning the component values (by moving sliders in a separate tuning window). The effect of both operations is shown in real time on the Smith chart and S parameter plots. Thus, the impedance trace visualization helps to understand the operation of the matching circuit and is also a great tool for teaching.

Optenni Lab — Graphical user interface
Optenni Lab has an intuitive graphical user interface that is very easy to use. Within minutes from the installation, you can start analyzing your antenna data.
The main features of the user interface are:
- A project tree where all the previously computed results are shown
- Editable labels in the project tree
- Capability to save and load project files containing the previously computed results
- Multiple projects open at the same time
- Dockable Smith chart and circuit plots
- Dockable tabular display of matching circuit performance on the pass and stop bands
- Copying plots to the system clipboard
- User plots where data from different plots and projects can be shown on the same plot
- Interactive markers showing information about the curves at selected frequencies
- Online help system