Only for production companies: SMS: A resonance-based electromagnetic measurement of planar dielectric material properties

We offer only one hardware solution including drawing of the special connectors up to 40 GHz and the contact to the software of the SMS-system for NVA- or other production companies.

SMS allows you to determine the frequency-dependent relative permittivity and the frequency-dependent loss tangent of your substrate. Your substrate can be any planar dielectric material within SMS’s specifications (see characteristics table below). SMS uses microstrip resonators and is therefore well suited to aid the design of microwave microstrip circuit boards even if your board (i.e. substrate) is anisotropic.

Fig. 1: A typical SMS setup showing the SMS hardware connected to a VNA.

Measurement setup: SMS consists of hardware and software to be used together with a vector network analyzer (VNA). (The VNA is not included.) The software can remote control your VNA through the entire measurement process.

Device under test: The DUT consists out of a bare substrate sample. No transmission line or circuit structures have to be designed on the DUT.

Data processing: After the measurements, the software computes the results using algorithms created by Prof. R.H. Jansen. Some main results SMS gives you are the permittivity and the loss tangent of your substrate for each found resonance frequency. The mean of these permittivities and the mean of these loss tangents can be considered as the permittivity and loss tangent of the sample in the measured frequency range. The default measurement frequency ranges of SMS are 0.5 GHz – 13 GHz and 0.5 GHz – 6 GHZ. However, upon request the software can be customized to change features such as the measurement frequency range.

Fig. 2: The SMS press-stand.
Fig. 3: The disassembled SMS press-stand with some of the antenna boards. (The antenna boards are grayish black with a copper metallization and are at the bottom in this photo.)

Included in the hardware is a press-stand to assure a good contact between the antenna plate and your substrate. The press-stand also contains built in connectors to connect it to the VNA. Also included as hardware is a ‚kit-box‘ containing antenna boards with various antenna designs.

SMS typical characteristics:


Sample size

56 x 64


Sample thickness range

0.5 – 1.5


Sample relative permittivity range

2 – 8


Sample loss tangent range

0.001 – 0.02


Connector ports

SMA female


Setup base plate diameter



Measurement frequency range

0.5 – 13 or 0.5 – 6 (customizable upon request)


The SMS software can remote control your VNA to speed up and automate the measurement process. It is also possible to control your VNA manually, in this case the SMS software will guide you through the measurement process allowing you to manually input measured values.

Fig. 4: A software window showing some of the preferences a user can select.
Fig. 5: A software window showing the final results of a measurement process in the graph representation.

Below is a table of communication hardware and VNA combinations which SMS is able to remote control. Each row in this table represents a remote control compatible combination. SMS’s remote control complies with several VNA vendors‘ protocols which typically guarantee compatibility to a series of VNA. However in the center column we list only the VNAs which we have tested and found to be compatible. In the right column are examples of VNA series which according to the protocol should be compatible but which we haven’t tested. This table will be expanded in the future as more setups are tested and found to be compatible. Please contact us for more information concerning your VNA if it is not in the table or if it hasn’t yet been tested by us.

Computer’s communication hardwareVNAs tested and found to be compatibleVNAs likely to be compatible

Agilent GPIB PCI card

Rohde & Schwarz ZVA50

Rohde & Schwarz ZVA-series with at least a 0.5 GHz – 13 GHz range.

National Instruments GPIB PCI card

Agilent 8510C

Agilent 8510-series (8510X-series), Agilent 8720-series (872X-series)

More details are explained in the operation manual: Now available

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