Fiber optic active antennas / field probes are used as a nearly ideal tool to probe an RF electric field without disturbing it by the probe itself or by the connected (metallic) coaxial cables. Therefore measurements even in the near field of radiating elements provide most accurate results.


The EFS-105 is the first in a family of fiber-optic active antennas & E-field probes.

The field distortion caused by the probe head is nearly zero due to the exceptionally small probe head and the all-optical signal transmission and power supply. This gives an invaluable advantage for near field measurements and measurements close to metallic parts.

probe head of the EFS-105

The small size of the probe head provides another great advantage: Measurements can be performed with a spatial resolution as high as never before. Thus the results get a lot more precise. And even highest field gradients can be analyzed.

From the user's point of view the system operates as a miniaturized very broadband active antenna with a flat frequency response - but invisible to the field.

The EFS-105 consists of the base unit and the probe head both connected by an optical fiber cable.

The probe head is optically powered by a high power laser diode which is contained within the base unit. There is no trouble with run out batteries just when the probe is needed. In addition long-term measurements are made possible.

base unit of the EFS-105

EFS-105 Key Data:

Probe head size:   6.6 × 6.6 × 42 mm
Frequency range:   500kHz ... 3GHz
(operation up to 5GHz+ with reduced sensitivity)
Sensitivity:   10µV/(m×√Hz) noise equivalent field strength 
Antenna factor:   typ. 46 ± 2dB(m-1)
Dynamic range:   typ. 130dB (1Hz)
Cable length:   5m and 10m as standard, other on request

PDF Icon   Datasheet EFS-105

Modifications, Special Requirements; Future Products

If you have special requirements like

we'll be glad to hear about your requirements. Feel free to contact us with your needs!

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Modified versions of the EFS-105 for higher frequencies will be available soon.