Secrecy outage probability of network-coded cooperation without channel state information

We evaluate the secrecy performance of a cooperative network where the destination node is wiretapped by a malicious and passive eavesdropper. We propose the application of the network coding technique as an alternative to increase the secrecy at the destination node, in a scenario without channel state information (CSI) at the transmitter side. Network coding is leveraged by assuming that the legitimate cooperative nodes are able to perform non-binary linear combinations of different frames before the transmission. Theoretic and numerical analyses show that the secrecy can be considerably increased through the use of network coding when compared to the direct transmission and traditional cooperative techniques.