In [1] the authors consider linearly independent channel covariance matrices, however, they do not mention if it is symmetric or not.
Therefore, I'd like to know if the covariance matrix for that case is symmetric.
[1] Emil Björnson, Jakob Hoydis, and Luca Sanguinetti,"Pilot contamination is not a fundamental asymptotic limitation in massive MIMO", IEEE International Conference on Communications (ICC), May 2017.
Thanks and Kind Regards,
Felipe