Relay channel

In information theory, a relay channel is a probability model of the communication between a sender and a receiver aided by one or more intermediate relay nodes. In information theory, a relay channel is a probability model of the communication between a sender and a receiver aided by one or more intermediate relay nodes. A discrete memoryless single-relay channel can be modelled as four finite sets, X 1 , X 2 , Y 1 , {displaystyle X_{1},X_{2},Y_{1},} and Y {displaystyle Y} , and a conditional probability distribution p ( y , y 1 | x 1 , x 2 ) {displaystyle p(y,y_{1}|x_{1},x_{2})} on these sets. The probability distribution of the choice of symbols selected by the encoder and the relay encoder is represented by p ( x 1 , x 2 ) {displaystyle p(x_{1},x_{2})} .