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Designing In-Place with the Integrated Transmission Line Calculator

The AWR Design Environment Transmission Line Calculator lets you calculate and set transmission line dimensions for a specified impedance and electrical length directly from microstrip, stripline, coplanar/rectangular waveguide, or coaxial components on a schematic, accelerating the design of distributed networks such as Wilkinson dividers, Branchline couplers, and quarter-wave transformers.

Using the Transmission Line Calculator

In the Transmission Line Calculator dialog box, the Physical property grid is initially populated with the schematic's center frequency (calculated as the center frequency of the frequency sweep), the model's physical parameters, and referenced substrate parameters. The physical units correspond to the project length units. If any of the physical parameters are equations, they are evaluated and the evaluated value is displayed. The Electrical property grid parameters are computed based on the physical parameters. To compute new electrical parameters, first make any changes to the physical parameters and click on the Analyze right arrow. (This is generally not necessary as an analysis is performed with the final physical values.)

To perform a transmission line synthesis:

1. In the Electrical property grid, select the Target check boxes for desired electrical parameters, and enter a corresponding value. Only the electrical parameters with the selected Target check boxes are used in the calculation.
   
   
2. In the Physical property grid, update frequency and substrate parameters if needed, then select the Synthesize check boxes for transmission line physical parameters to synthesize based on the targets.
   
   
3. Click the Synthesize left arrow to run the synthesis program. The values in both property grids update with the synthesized results. An analysis is also performed with the final physical values. If synthesis cannot achieve the target values, it shows how close it came.
   
   
4. Click OK to update the selected transmission line element with the synthesized physical parameters and close the dialog box. Expressions are overwritten with the new, evaluated values. You can click the Undo button on the program toolbar to revert all parameters to their pre-synthesized state. Parameters from substrate elements are never updated, since substrate elements are typically used by more than one transmission line element. You can also click Cancel to close the dialog box without changing the element parameters.

Related Resources

Videos

• Integrated Transmission Line Calculator (Cadence YouTube Knowledge and Learning subchannel; 5 mins.)

Blogs

• μWaveRiders: Cadence AWR Design Environment V16 Software Release Highlights

Examples

• Transmission Line Synthesis example