Opportunistic source‐pair selection method with imperfect channel state information for multiuser bi‐directional relaying networks

Cancel‐Decode‐Encode Processing on Two‐Way Cooperative NOMA Schemes in Realistic Conditions

“…We also assume that the flat and block Rayleigh fading channels with the fading coefficients for links S k ⟶ R i and R i ⟶ S k are denoted as h S k R i and h R i S k , respectively, where k ∈ f1, 2g. In addition, perfect knowledge of all links is assumed at the receivers by channel estimators that are error-free [35], and the ipCSIs are only caused by the feedback delay with a time-variant channel representation and is described by [12,14,16,20,22,32,35]…”

“…The partial relay selection does not offer the full spatial diversity, but it is not as complicated as the full relay selection, and it is useful for applications in industrial IoT and wireless sensor networks. In most practical applications, CSIs cannot be perfectly measured and there are some mismatch, known as imperfect CSIs (ipCSIs) [12,14,16,[19][20][21][22]. The mismatch can happen due to the feedback delays of the CSIs [12,14,16,19,22] or the faults in the CSI estimating process [20,21].…”

“…In most practical applications, CSIs cannot be perfectly measured and there are some mismatch, known as imperfect CSIs (ipCSIs) [12,14,16,[19][20][21][22]. The mismatch can happen due to the feedback delays of the CSIs [12,14,16,19,22] or the faults in the CSI estimating process [20,21]. One-way NOMA and cooperative NOMA (CNOMA) networks with the SIC have been widely discussed to increase spectral efficiency gain, improve secure performance, enlarge system energy efficiency, and enhance significantly sum throughput in several studies [1,4,[23][24][25].…”

Joint source‐pair and relay selection for relay‐assisted network

“…Ozduran and Yarman [34] extend the system model of [32, 33] by taking into consideration the co‐channel interference (CCI) effects. Ozduran et al [35] extend [32, 33] by assuming that the CSI is imperfect because of the channel estimation error (CEE) and feedback delay (FD). Ozduran and Yarman [34] also use the same user‐pair selection strategy as [32, 33] for the ICI challenge.…”

Multi‐user two‐way relaying in the presence of co‐channel interference

“…Ozduran et al [16] presented an alternative technique, which is based on sum‐rate (SR) based user‐pair selection, for dealing with ICI in multiuser systems and [17] is more generalised [16] to focus more on a theoretical analysis of this problem. Ozduran et al [18] extended [16, 17] by considering more realistic scenario that the CSI is imperfect because of the channel estimation error (CEE) and feed‐back delay. Ozduran [19] extended [16, 17] by assuming that system model contains multiple relay instead of a single relay.…”