MESA Solutions specialises in measurement science, and uses both frequency domain (FD) and time domain (TD) techniques to investigate EMC and interference problems. This is true for both radiated and conducted noise measurements. Some of the tools that MESA uses include various antennas, current probes, spectrum analyzers, oscilloscopes and time domain measurement devices using FPGA technology.
Conducted noise measurements are made using a common mode (CM) current probe and Rogowski coils covering a frequency range up to 1 GHz. We are also able to conduct near-field scans to assist with PCB-based interference between 9 kHz - 1 GHz. Our spectral coverage include the following:
Common Mode Current Measurements
10 Hz - 1 GHz
MESA considers accurate characterisation of common mode current a key tool help identify potential sources of interference. With the measurements being performed at source, background contributions from external environmental sources are limited. Conducted interference also provides a basis for correlation with radiated results assuming resonant, or near-resonant, cable lengths.
HF - VHF
25 MHz - 80 MHz
30 MHz to 280 MHz
The high to very high frequency band is traditionally a very active part of the radio frequency spectrum, mostly due to FM radio and traditional analogue television stations. Continuous coverage across this range of frequencies is therefore important, and for this MESA uses a HFU2-Z1 broadband dipole and restively-load monopole antenna. Suitable LNAs are available to help improve measurement sensitivity if required.
VLF - HF
9 kHz to 30 MHz
For the very low to high frequency radiated interference, MESA makes used of a Rohde & Schwarz HFH2-Z2 magnetic loop antenna. This robust device enables real-time identification of interference simply by rotating it through orthogonal directions. The integrated FET pre-amplifier ensures adequate sensitivity to perform EMI measurements in line with various standards (i.e. CISPR, MIL, FCC, ANSI, ETSI).
VHF - SHF
80 MHz - 1.3 GHz
300 MHz - 10 GHz
Two broadband log periodic dipole array antennas are used to cover the frequency range up to 10 GHz. Both antennas can be mounted on a height-adjustable mast capable of increasing elevation to 4.5 m. Calibration data including polar patterns across the frequency range enable us to deembed antenna performance and provide accurate E-field levels necessary for qualification purposes.