Beamforming strategies for multi‐antenna relay‐assisted networks

Secrecy sum rate maximisation in multi‐antenna two‐way relay networks

“…4The CSI associated with all links are fully known at a central node. This is a common assumption in some related works including [10][11][12][13][17][18][19]. This is a realistic assumption when all nodes are registered nodes of the network.…”

“…The mutual information in (11) can be formulated as (see (12)) (see (13)) (see (14)) (see 15)where p 1 and p 2 are the powers of x 1 and x 2 , respectively. Also, due to the half-duplex relaying mode, the coefficient 1/2 is being used.…”

“…Recently, many researches have been done on the physical layer security in one-way relay-assisted cooperative networks employing the AF strategy [10][11][12][13]. Also, there have been a tremendous demand to employ two-way bandwidth efficient communication protocols to enhance the spectral efficiency [14].…”

“…On the other hand, since multi-antenna multi-relay network yields an additional improvement through providing more degrees of freedom, some works are devoted to investigate cooperative relaying strategies [12,17,18]. This motivated us to pursue addressing the same issue in a two-way relay network as is depicted in Fig.…”

On the secrecy rate balancing problem of two‐way multiple‐input multiple‐output relaying networks using rank‐1 beamforming strategy

“…Accordingly, a tremendous amount of research is devoted to exploring effective transmission strategies in such networks to enhance the secrecy rate problem. [11][12][13][14] The works in Mirzaee et al, 15,16 extended the problem to a more general case of incorporating multiple multi-antenna relays and some single-antenna eavesdroppers. In work of Jenog et al, 17 studied the problem of joint transmit and relay beamforming vectors in terms of maximizing the achievable secrecy rate in multi-antenna Amplify and Forward (AF) relay-assisted one-way network with a direct transmitter-to-receiver link.…”