This study investigates wireless information and energy transfer for dual-hop amplify-and-forward full-duplex relaying systems. By forming energy efficiency (EE) maximization problem into a concave fractional program of transmission power, three relay control schemes are separately designed to enable energy harvesting and full-duplex information relaying. With Rician fading modeled residual self-interference channel, analytical expressions of outage probability and ergodic capacity are presented for the maximum relay, signal-to-interference-plus-noise-ratio (SINR) relay, and target relay. It has shown that EE maximization problem of the maximum relay is concave for time switching factor, so that bisection method has been applied to obtain the optimized value. By incorporating instantaneous channel information, the SINR relay with collateral time switching factor achieves an improved EE over the maximum relay in delay-limited and delay-tolerant transmissions. Without requiring channel information for the second-hop, the target relay ensures a competitive performance for outage probability, ergodic capacity, and EE. Comparing to the direct source-destination transmission, numerical results show that the proposed relaying scheme is beneficial in achieving a comparable EE for low-rate delay-limited transmission.
This letter analyzes and compares the performance of full-duplex relaying (FDR) and half-duplex relaying (HDR) for ultra-reliable short-packet communications. Specifically, we derive both approximate and asymptotic closed-form expressions of the block error rate (BLER) for FDR and HDR using short packets with finite blocklength codes. We define and attain a closed-form expression of a critical BLER, which can be used to efficiently determine the optimal duplex mode for ultra-reliable low latency communication scenarios. Our results unveil that FDR is more appealing to the system with relativel…
Cooperative Strategies for the Half-Duplex Gaussian Parallel Relay Channel: Simultaneous Relaying versus Successive Relaying
研究了在加性高斯白噪声环境下,两个半双工并联继电器组成的网络的通信问题。两个协议,即,提出了与两种可能的中继排序相关联的\emph{Simultaneous}和\emph{Successive}中继。同时中继协议基于\emph{Dynamic Decode and Forward (DDF)}方案。对于连续中继协议:(i)考虑基于\emph{Dirty Paper Coding (DPC)}的\emph{Non-Cooperative}方案,以及(ii)考虑基于\emph{Block Markov Encoding (BME)}的\emph{Cooperative}方案。此外,与\emph{Cooperative}方案相比,在一个中继器处采用BME而在另一个中继器处采用DPC的复合方案总是实现更好的速率。还提出了一种\emph{"Simultaneous-Successive Relaying based on Dirty paper coding scheme" (SSRD)}。中继的最佳顺序,从而在低和高的信号噪声比(SNR)的情况下,半双工高斯并行中继信道的容量推导。在低信噪比的情况下,它揭示了在一定的条件下的信道系数,基于DDF的同时中继的可达速率的割集界的比值趋于1。另一方面,当信噪比趋于无穷大时,证明了基于DPC的连续中继渐近地达到网络的容量。
The hybrid half-duplex/full-duplex (HD/FD) relaying scheme is an effective paradigm to overcome the negative effects of the self-interference incurred by the full-duplex (FD) mode. However, traditional hybrid HD/FD scheme does not consider the diversity gain incurred by the multiple antennas of the FD node when the system works in the HD mode, leading to the waste of the system resources. In this paper, we propose a new hybrid HD/FD relaying scheme, which utilizes both the antennas of the FD relay node for reception and transmission when the system works in the HD mode. With multiple antennas,…
In this paper, we propose a comprehensive research over triple hop all-optical relaying free-space optical (FSO) systems in the presence of all main noise sources including background, thermal and amplified spontaneous emission (ASE) noise and by considering the effect of the optical degree-of- freedom (DoF). Using full CSI relaying, we derive the exact expressions for the noise variance at the destination. Then, in order to simplify the analytical expressions of full CSI relaying, we also propose and investigate the validity of different approximations over noise variance at the destination. …
Relay Assisted F/TDMA Ad Hoc Networks: Node Classification, Power Allocation and Relaying Strategies
本文考虑了中继辅助的F/TDMA ad hoc网络的设计与多个中继节点,其中每个节点协助传输的一个预定义的子集的源节点到各自的目的地。考虑总容量作为性能指标,我们解决了最优分配的问题,每个中继节点的总功率之间的传输,它是协助。我们考虑四种不同的中继传输策略,即再生解码转发(RDF)、非再生解码转发(NDF)、放大转发(AF)和压缩转发(CF)。我们首先获得的中继节点,采用统一的中继策略的最佳功率分配政策的所有节点。我们发现,最佳的RDF和NDF的情况下的功率分配修改注水解决方案。我们观察到,对于一个给定的中继传输功率,NDF总是优于RDF,而CF总是提供更高的总和容量比AF。当CF和NDF进行比较,它是观察到,CF或NDF可能优于其他在不同的情况下。这一观察表明,总容量可以进一步提高每个中继采用中继策略,帮助不同的源节点。我们接下来研究这个问题,并确定中继节点协助的每个源节点的最佳功率分配和中继策略。我们观察到,最佳功率分配的中继节点与混合中继策略提供了更高的总容量比纯RDF,NDF,AF或CF中继策略。
In this paper, a symbol-level selective transmission for full-duplex (FD) relaying networks is proposed to mitigate error propagation effects and improve system spectral efficiency. The idea is to allow the FD relay node to predict the correctly decoded symbols of each frame, based on the generalized square deviation method, and discard the erroneously decoded symbols, resulting in fewer errors being forwarded to the destination node. Using the capability for simultaneous transmission and reception at the FD relay node, our proposed strategy can improve the transmission efficiency without extr…
Hybrid relaying networks (HRNs) combining both a relay and an intelligent reflective surface (IRS) can lead to enhanced rate performance compared to non-hybrid relaying schemes, where only either an IRS or a relay is utilized. However, utilizing both the relay and the IRS simultaneously results in higher power consumption for the HRNs compared to their counterpart. In this work, we study the required transmit power levels and the energy efficiency (EE) of HRNs utilizing both a half-duplex decode-and-forward (HD-DF) relay and an IRS, and compare their performance with non-hybrid relaying scheme…
We develop an analytical framework to characterize the effect of impulsive noise on the performance of relay-assisted simultaneous wireless information and power transfer (SWIPT) systems. We derive novel closed-form expressions for the pairwise error probability (PEP) considering two variants based on the availability of channel state information (CSI), namely, blind relaying and CSI-assisted relaying. We further consider two energy harvesting (EH) techniques, i.e., instantaneous EH (IEH) and average EH (AEH). Capitalizing on the derived analytical results, we present a detailed numerical inve…
In this paper, we consider a two-hop amplify-and-forward (AF) relaying system, where the relay node is energy-constrained and harvests energy from the source node. In the literature, there are three main energy-harvesting (EH) protocols, namely, time-switching relaying (TSR), power-splitting (PS) relaying (PSR) and ideal relaying receiver (IRR). Unlike the existing studies, in this paper, we consider $α$-$μ$ fading channels. In this respect, we derive accurate unified analytical expressions for the ergodic capacity for the aforementioned protocols over independent but not identically distribut…
In this paper, we investigate opportunistic relaying and jamming techniques and develop relay selection algorithms that maximize the secrecy rate for multiuser buffer-aided relay networks. We develop an approach to maximize the secrecy rate of relay systems that does not require the channel state information (CSI) of the eavesdroppers. We also devise relaying and jamming function selection (RJFS) algorithms to select multiple relay nodes as well as multiple jamming nodes to assist the transmission. In the proposed RJFS algorithms inter-relay interference cancellation (IC) is taken into account…