Integrating AWR Microwave Office Designs into NI Multisim

[Mahmoud_W]

Hello Circuit Designers,

I would like to share with you a new proof of concept design that takes advantage of multiple NI tools. The design is a Low Noise Amplifier (LNA) operating at 10 GHz fully analyzed in AWR's Microwave Office. Along with the LNA, a peripheral low-frequency circuit providing the needed bias levels for the FET is simulated in NI Multisim. Finally, the LNA is imported into Multisim as a footprint only component to be combined with the bias circuit. A final PCB prototype of the complete system is created using NI Ultiboard.

1. Evaluation of the 10 GHz LNA performance in MWO

This design of a 10 GHz LNA built on 10 mil alumina is using a NEC 76038 GaAs MESFET.  Running the analysis of the circuit, you learn that the LNA has 7.7dB gain and 2.15dB NF at 10 GHz.

Designing this amplifier in MWO you can take advantages of the real-time tuning, frequency subset Smith Chart plots of noise and matching circles, and the X-Models for discontinuities accuracy to validate the performance of the amplifier.

2. Creation of a LNA footprint component to use in Multisim

This step means to export the layout of this LNA in a DXF format and integrate it into Multisim as a new component.

3. Design of low frequency bias network in Multisim

The next step in this example is to accurately validate the circuit performance of a biasing circuit that takes a 12VDC input and outputs 2 arbitrary voltage levels for Gate and Drain biasing of the MESFET at -0.7V and 5V respectively. Eventually this bias circuit will be integrated with the LNA on a single PCB.

4. Prototyping the complete system in Ultiboard

Finally, the LNA component is added to the Multisim design and a final PCB layout is created using Ultiboard.

Let me know if you have ideas for similar use-cases.

Mahmoud W

National Instruments