Millimeter-wave (mmWave) Calibration Challenges
White Papers
The objective of calibration at millimeter wave frequencies is no different than at longer wavelengths: remove the largest contributor to measurement uncertainty. But the reality is while the objective is the same, the actual process for achieving the calibration is quite different.
When testing mmWave devices, you need to be aware of the unique challenges of calibration at frequencies of 30- 300 GHz.
Even the best hardware can’t eliminate all the potential errors generated during device testing. All testing hardware has some degree of innate imprecision. And at mmWave frequencies, wavelengths are smaller, which means greater sources of error to the measurement from relatively small changes to the measurement plane. In other words, a shift of only a few millimeters can lead to large phase shifts. This tight margin makes it even more critical for you to minimize these errors with proper calibration.
You’re likely familiar with standard network analyzer calibration and vector-error-corrected measurements. This is often a routine part of maximizing the accuracy of your measurements (by minimizing the innate imprecision of your network analyzer). But, at mmWave frequencies, there are special calibration considerations to make that are essential for accurate, repeatable measurements in these high frequency bands. So what changes do you need to make for working in the mmWave frequency range? How can you ensure you’re getting the most reliable measurements and avoiding costly test errors?