Measurement uncertainty of RC and its reduction techniques for OTA tests: a review

摘要

The emerging machine-to-machine (M2M) communications and Internet-of-things techniques bring new challenges in over-the-air (OTA) tests. The inexpensive M2M device usually aims at low-cost and low-power consumption rather than high data rate and, therefore, is usually equipped with a single antenna. Testing such M2M device in massive production requires efficient and cost-effective OTA techniques. The reverberation chamber (RC) is a suitable solution for such tests of M2M (especially large-form-factor) devices. Since RC measurements are in essence stochastic measurements (with repeatable results), uncertainty analyses are of primary importance. This study gives an overview of the start-of-the-art research on measurement uncertainty for both conventional and M2M OTA applications. In addition, new results about mode stirrers and diffusers (for uncertainty reduction) are provided.