Distributed spatial multiplexing in a wireless network

We study a wireless network with one source-destination pair and several relays that forward the data from source to donation in a multi-hop fashion. We compare two schemes: i) The relays operate in an amplify-and-forward (AF) mode and establish a point-to-point MIMO channel between source and destination (MIMO tunnel), ii) The relays operate in a decode-and-forward (DF) mode and the data Is transmitted over different network paths (multi-path transmission). We show that the MIMO tunnel with AF relays outperform the multipath transmission with DF relays with respect to information rates.