On the capacity of the binary‐symmetric parallel‐relay network
Transactions on Emerging Telecommunications Technologies, 2014•Wiley Online Library
We investigate the binary‐symmetric parallel‐relay network where there is one source, one
destination, and multiple relays in parallel. We show that forwarding relays, where the relays
merely transmit their received signals, achieve the capacity in two ways: with coded
transmission at the source and a finite number of relays, or uncoded transmission at the
source and a sufficiently large number of relays. On the other hand, decoding relays, where
the relays decode the source message, re‐encode, and forward it to the destination, achieve …
destination, and multiple relays in parallel. We show that forwarding relays, where the relays
merely transmit their received signals, achieve the capacity in two ways: with coded
transmission at the source and a finite number of relays, or uncoded transmission at the
source and a sufficiently large number of relays. On the other hand, decoding relays, where
the relays decode the source message, re‐encode, and forward it to the destination, achieve …
Abstract
We investigate the binary‐symmetric parallel‐relay network where there is one source, one destination, and multiple relays in parallel. We show that forwarding relays, where the relays merely transmit their received signals, achieve the capacity in two ways: with coded transmission at the source and a finite number of relays, or uncoded transmission at the source and a sufficiently large number of relays. On the other hand, decoding relays, where the relays decode the source message, re‐encode, and forward it to the destination, achieve the capacity when the number of relays is small. In addition, we show that any coding scheme that requires decoding at any relay is suboptimal in large parallel‐relay networks, where forwarding relays achieve strictly higher rates. Copyright © 2012 John Wiley & Sons, Ltd.