Project Description

  • Project Starting Date

    1.01.2021

  • Project End

    31.3.2021

  • Category

    Research

Project Description

The task was/is to build a reliable electromagnetic field meter, capable of withstanding intensities of the order of 100 V/m, with a specific field strength in the frequency band 80 – 800 MHz with an intensity of 10 – 60 V/m. The first version of the Pixla 1 meter is autonomous – able to measure and record data independently for about 10 hours on its own power supply, recording its position from GPS data and is partially controllable via WiFi. The device is in a shielded enclosure designed to prevent any extraneous signals from entering the interior. It can measure and store three frequencies simultaneously.

The instrument will be used to measure the directional characteristics of antenna systems of 10- 100 kW power during pre-inspection or replacement of radiators.

The Challenge in the design

The operation and immunity of Pixle 1 was verified in the Electromagnetic Compatibility Laboratory of FEI STU. The device was located in a 50 V/m field, while the field frequency was switched from 80 MHz to 1 GHz. The device was configured to receive and record a signal with a frequency of 96 MHz only. This signal was captured with no increase in the background of the unmeasured signal (we can speak of interference). Pixel 1 responded to amplitude changes linearly with the change in the incident signal – the electromagnetic field. There was no penetration of the electromagnetic field into the interior of the device/inside the enclosure by other than the desired paths.

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When the frequency modulation was switched on at 96 MHz, the recorded signal/data was stable. Despite increasing the frequency stroke of the frequency modulation, the recorded data, at a constant level of electromagnetic field magnitude, did not change. Again, there was no increase in the background of the measured signal, or cluttering/saturation of the instrument.

The Final Output

The first version of the electric component of the electromagnetic field meter.

  • Frequency range 10 MHz – 850MHz
  • Measured field strength 1 – 100 V/m, depending on the attenuator used
  • Mechanically resistant device
  • Partly user fiendly and foolproof device
  • Ability to measure 3 frequencies simultaneously