Common Pitfalls in Multidimensional High Resolution Channel Parameter Estimation

The structural properties of multi-path channels such as directions of arrival and departure are estimated from multidimensional channel sounder data by application of high-resolution parameter estimation methods. However, the influence to the accuracy and reliability of the results due to antenna calibration errors and mismatch of the data model which is used by the parameter estimator are often underestimated. We describe the antenna array calibration procedure and discuss common pitfalls in high-resolution multi-path direction estimation that are related to inaccurate and/or incomplete data models that result from using only subsets of the full solid angle polarimetric antenna response. Depending on the type of the antenna array used (linear, circular) this will inherently produce biased and artificially spread angular estimates.