In cooperative MIMO relaying systems, channel estimation involves estimating channel matrices at the receiver and/or relay. Starting from this setup and its generalizations (multiple relays, three-hop, and multi-hop cases), tensor decompositions have been largely applied to solve the channel estimation and the joint channel-symbol estimation problems for tensor-coded MIMO relaying systems.

Figure 9: Tensor modeling in MIMO relaying systems uses tensor coding matrices at the source and the relay nodes. The received signal tensor follows a tensor train model.

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