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

Abstract

This paper considers the effects of perfect/imperfect successive interference cancellation (SIC) and perfect/imperfect ` information (CSI) in a multiple-relay two-way cooperative network using nonorthogonal multiple access (NOMA) and digital network coding (DNC). In this model, a relay is selected by maximizing estimated channel gains to enhance the decoding capacity of the nearer source and minimize the collection time of imperfect CSI. Spectrum utilization efficiency is enhanced two times by a mixture of the SIC and DNC techniques at the selected relay (called as the SIC-2TS protocol). The system performance is considered through analysis of the exact and asymptotic expressions of the system outage probabilities and throughput. The major thing is exposed as the proposed SIC-2TS protocol can reach the best performance at optimal positions of the selected relay. Besides, the system throughput of the proposed protocol outperforms a SIC-utilized two-way relaying scheme without the DNC (called as the SIC-3TS protocol) and a conventional two-way scheme (called as the CONV-4TS protocol) for all signal-to-noise ratio regions. Lastly, the validity of the analytical expressions is verified by the Monte Carlo simulation results.

Outage Performance of Interference Cancellation-Aided Two-Way Relaying Cognitive Network with Primary TAS/SC Communication and Secondary Partial Relay Selection

“…Looking at Figure 3, we also see that the transmit power of all secondary transmitters increases as P PT increases. Moreover, as proven in (35), the transmit power of all secondary transmitters linearly increases at high P PT region. From Figure 2, we can observe that the simulation results validate the theoretical ones of OP P1 , OP P2 , and OP P0 derived in Section 3.…”

“…In contrast to [27][28][29][30][31], in this paper, ICT is used to reduce one transmission time slot for the DNC TWR networks. Unlike [33][34][35], our proposed scheme applies PRS to the secondary network. Moreover, this paper considers block fading channels, in which channel coefficients do not change during one data transmission cycle, but independently change after each cycle.…”

“…However, the disadvantage of DNC TWR is that this technique must use three time slots for each data exchange. To enhance the data rate for DNC TWR, the published works [33][34][35] applied the interference cancellation technique (ICT) at the common relay, and hence the schemes proposed in [33][34][35] also obtained the data rate of 02/02. This paper proposes the DNC TWR scheme operating in the underlay spectrum sharing mode.…”

Performance analysis of power‐domain non‐orthogonal multiple access for full‐duplex two‐way relaying

“…More specifically, the selecting criterion is based on choosing the relay the highest signal‐to‐interference‐plus‐noise‐and‐distortion ratio. The practical issues of imperfect CSI and SIC when selecting the best relay are considered in Reference 39, selecting a relay according to the maximum estimated channel gains. Finally, in an FD multi‐relay network, the study in Reference 40 employs rate splitting and successive group decoding, leveraging the interference signals from neighboring users.…”