MMW isolators incorporate internal magnets to align the magnetic dipoles in the ferrite core and achieve Faraday rotation of the signal. Because our isolators use a saturated magnetic bias field, they are insensitive to stray magnetic fields from external sources such as those arising from other nearby ferrite devices. In contrast, traditional style isolators manufactured by other vendors are highly sensitive to stray magnetic fields. The sensitivity is caused by the fact that the magnetic bias point lies on the steep part of the magnetization curve. This is just one more reason to choose Micro Harmonics isolators.
Micro Harmonics has done extensive stray magnetic field testing in the W-band. Our isolators can withstand stray magnetic fields with more than ± 220 Oe with no detectable change in the insertion loss. Conversely, traditional style isolators were found to be highly susceptible to stray fields as indicated in the graph. Watch the video on the left for a demonstration of the impact of stray magnetic fields. Or for more information read the The Impact of Stray Magnetic Fields on MMW Isolators whitepaper published in the April 2021 edition of the Microwave Journal.