CRF Logo Newsletter Fall 2011

Save Time with Simulation

Computer simulation has become a common design tool. Thanks to today’s computers, designs that only a few years ago would have been impractical to analyze can now be quickly characterized without a supercomputer. Laborious computations, guesswork and extensive prototyping are no longer needed. Whether we like to tinker or not, fast-executing and accurate computer models can decrease the number of hardware iterations thereby reducing development cost and time.

Electrical engineers can now simulate the performance and predict the behavior of complex distributed element circuits, such as printed circuit boards (and their @!$#%^ parasitics!) at microwave frequencies. Even true 3-dimensional structures such as antennae or waveguide components fall within the purview of computer simulation.

CustomRF Example

CustomRF specializes in 3-dimensional electromagnetic field simulations of just such structures. Here is a simple example.

BPF Picture

Bandpass Filter
(cover removed)
BPF Model

Bandpass Filter Model
(CST Microwave Studio)

This interdigital bandpass filter consists of coupled transmission lines. To achieve the right response, each line must have the correct length, width and placement. Design equations are a good start, but fine-tuning is still required. In the past we would build a board, measure, scrape off a bit of trace, measure, build another board, measure ... sound familiar?

At CustomRF, we make a model, simulate, make a minor change, simulate, make another change, simulate, ... much easier! Or we parametrize the model and let the computer find and deliver the dimensions to us when finished. With simulation it is possible to get much closer on the first try. In our example above, when we simulated the filter's S-Parameters and compared the results to VNA measurements, we obtained good agreement.

Insertion Loss Return Loss

More examples can be found on the CustomRF web site.


Simulating the design before building
  • Saves prototyping
  • Saves time
  • Saves money
  • Looks good in a design report
The next time you need to develop distributed microwave circuits, or other circuits, consider simulation. If you do not have the tools and know-how ... there's always CustomRF.

About CustomRF

CustomRF was founded in 2003. Our customers range from small to mid sized companies, early stage to well established, whom we have helped design new products and improve and trouble shoot existing ones. Current and past customers include
  • AES Intellinet
  • Bandspeed
  • C & C Technologies
  • Finish Line Product Development
  • Maguffin Microwave
  • octoScope
  • Philips Semiconductor
Heinz Bachmann is now the sole owner of CustomRF. He has more than 20 years of technical, marketing and management experience in the analog, RF and microwave arena. His expertise is in concept development, systems architecture and analysis, and simulation and hardware design. Before founding CustomRF he was employed in engineering, marketing and management functions at Philips Semiconductor, Systemonic, Raytheon, Advanced TechCom and GTE. He received his Diploma in Electrical Engineering from the ETH (Federal Institute of Technology), Zürich, Switzerland in 1986. Heinz Photo

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