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A communication-efficient protocol is introduced over a many-to-one quantum network for Q-E-B-MDS-X-TPIR, i.e., quantum private information retrieval with MDS-X-secure storage and T-private queries. The protocol is resilient to any set of up to E unresponsive servers (erased servers or stragglers) and any set of up to B Byzantine servers. The underlying coding scheme incorporates an enhanced version of a Cross Subspace Alignment (CSA) code, namely a Modified CSA (MCSA) code, into the framework of CSS codes.

In MIMO communications, information about the transmitted signal is conveyed to the receiver through fields and currents on the surface of the receive antenna array. However, this information can only be observed indirectly through the ports of the array. This raises fundamental information-theoretic questions: How much useful information is contained in the fields and currents on the surface of the receiver array? How much of this information is captured by the array ports?