Spectrum-Energy Efficiency Tradeoff in Decode-and-Forward Two-Way Multi-Relay Networks

Abstract

Owing to its high spectrum efficiency (SE), two-way relaying has aroused tremendous research interests. In this paper, the spectrum-energy efficiency (SE-EE) trade-off in decode-and-forward (DF) two-way multi-relay networks is studied by considering non-ideal power amplifiers and non-negligible circuit. Firstly, we consider the scenario of several relay nodes. To achieve better performance, the relay node with the highest energy efficiency (EE) is selected as the optimal one. Secondly, we design the optimal power allocation method to allocate each node with the optimal transmission power to enhance EE and SE. Finally, we evaluate the performance of our method and additionally analyze how the change of relay nodes' relative position influences the EE and SE. Simulation results show that: 1) the proposed method can achieve higher SE than optimal relay equal power allocation, random relay equal power allocation, and optimal power allocation only; 2) the proposed method can achieve higher EE than optimal relay equal power allocation, random relay equal power allocation, and optimal power allocation only; and 3) EE and SE increase at first and then decrease when relay nodes move from the middle of the source node and destination node to both ends.INDEX TERMS Decode-and-forward (DF), energy efficiency (EE), multi-relay, relay selection, spectrum efficiency (SE), two-way relay.

Two‐way decode and forward quadrature media‐based modulation for single‐input multiple‐output scheme

“…The theoretical ABER results expressed in Equation (10) and MCS results obtained for the proposed system (two-way DF-QSM aided SIMO-MBM) are also shown in Figure 3. The average theoretical result obtained shows a tight fit with the MCS result, validating the theoretical expression.…”

“…1 This has encouraged tremendous research in MIMO schemes. [2][3][4][5][6][7] An innovative form of MIMO scheme to consider is spatial modulation (SM), 2 which increases the energy efficiency (EE) [8][9][10] and improves the drawback of conventional MIMO schemes with the requirement of a single radio frequency (RF) chain per transmission interval. However, SM still requires many transmit antennas to achieve a high data rate limiting its practical implementation with reference to complexity.…”

Design of a Reconfigurable Intelligent Surface Algorithm Based on Multiple-Input Multiple-Output

“…This paper devises an RIS-assisted cellular-free network, evaluates the WSR and other properties of the network, and designs a joint precoding scheme, which optimizes the network capacity by maximizing the WSR. The results simulation show that, with the help of energy-efficient and low-cost RIS, the proposed RIS-assisted cellular-free massive MIMO network can achieve higher capacity than traditional cellular-free networks, reduce transmit power [15], improve the transmission efficiency and reliability [16], and expand the coverage of wireless transmission [17][18][19][20][21][22][23][24][25][26][27].…”

Bidirectional Selective Detect-and-Forward (DetF) Multi-Relay Systems With Regularized WDFDC Receivers

“…When α = 0, the penalty function is zero and ( 12) is equivalent to (11). In [28], based on simulation results, the parameter α is fitted to a logistic function and calculated by α f = 0.5 1+e −p 2 (SN R R,dB −p 3 ) where p 2 = 0.119878295501326 , p 3 = 47.802208775435666 and SN R R,dB is the SNR at the relay.…”

“…I NTEREST in cooperative communications and relay networks has increased dramatically over recent years since such systems provide diversity advantages with relatively low complexity [1]- [11]. The Two-Way Relay Network (TWRN), where two terminals exchange information with the assistance of a relay, has received much attention in the literature [5] [6] [7] [9] [11] since it achieves higher transmission efficiency and network throughput than One-Way Relay Network (OWRN) [12]. In particular biderectional relaying has been found of interest to 6G systems [1] and IoT applications [2].…”