In this work, a new static relaying protocol is introduced for half duplex single-relay networks, and its performance is studied in the context of communications over slow fading wireless channels. The proposed protocol is based on a Decode or Quantize and Forward (DoQF) approach. In slow fading scenarios, two performance metrics are relevant and complementary, namely the outage probability gain and the Diversity-Multiplexing Tradeoff (DMT).
First, we analyze the behavior of the outage probability P_o associated with the proposed protocol as the SNR tends to infinity. In this case, we prove that SNR^2 P_o converges to a constant. We refer to this constant as the outage gain and we derive its closed-form expression for a general class of wireless channels that includes the Rayleigh and the Rice channels as particular cases. We furthermore prove that the DoQF protocol has the best achievable outage gain in the wide class of half-duplex static relaying protocols. A method for minimizing the outage gain with respect to the power distribution between the source and the relay, and with respect to the durations of the slots is also provided.
Next, we focus on Rayleigh distributed fading channels to derive the DMT associated with the proposed DoQF protocol. Our results show that the DMT of DoQF achieves the 2 by 1 MISO upper-bound for multiplexing gains r < 0.25.
Robust transceiver design against unresolvable system uncertainties is of crucial importance for reliable communication. For instance, full-duplex communication suffers from such uncertainties when canceling the self-interference, since the residual self-interference (RSI) remains uncanceled due to imperfect channel knowledge. We consider a MIMO multi-hop system, where the source, the relay and the destination are equipped with multiple antennas. We allow multi-stream beamforming granted by MIMO technique, without restricting the transmissions to single streaming. The relay can operate in eith…
The problem of lossy transmission of correlated sources over memoryless two-way channels (TWCs) is considered. The objective is to develop a robust low delay and low complexity source-channel coding scheme without using error correction. A simple full-duplex channel optimized scalar quantization (COSQ) scheme that implicitly mitigates TWC interference is designed. Numerical results for sending Gaussian bivariate sources over binary additive-noise TWCs with either additive or multiplicative user interference show that, in terms of signal-to-distortion ratio performance, the proposed full-duplex…
Robust transceiver design against unresolvable system uncertainties is of crucial importance for reliable communication. For instance, full-duplex communication suffers from such uncertainties when canceling the self-interference, since some residual self-interference (RSI) remains uncanceled due to imperfect channel knowledge. We consider a MIMO multi-hop system, where the source, the relay and the destination are equipped with multiple antennas. The considered decode-and-forward (DF) hybrid relay can operate in either half-duplex or full-duplex mode, and the mode changes adaptively depending…
This paper studies the spectral/energy efficiency (SE/EE) of a heterogeneous network with the backhaul enabled by low-resolution analog-to-digital converters (ADCs) quantized full-duplex massive multiple-input multiple-output (MIMO) over Rician channels. Backhaul communication is completed over two phases. During the first phase, the macro-cell (MC) base station (BS) deploys massive receive antennas and a few transmit antennas; the small-cell (SC) BSs employ large-scale receive antennas and a single transmit antenna. For the second phase, the roles of the transmit and receive antennas are swit…
We propose composite decode-forward (DF) schemes for the two-way relay channel in both the full- and half-duplex modes by combining coherent relaying, independent relaying and partial relaying strategies. For the full-duplex mode, the relay partially decodes each user's information in each block and forwards this partial information coherently with the source user to the destination user in the next block as in block Markov coding. In addition, the relay independently broadcasts a binning index of both users' decoded information parts in the next block as in independent network coding. Each te…
In this paper, we address the power allocation problem for a decode and forward (DF) relay system, where a massive multiple-input-multiple-output (mMIMO) multi-carrier (MC) base station (BS) node communicates with a MC single antenna node directly and also through the single antenna full duplex (FD) MC relay, using rate splitting (RS) approach. Successive interference cancellation approach is adopted at the destination. We consider orthogonal frequency division multiplexing (OFDM) as our MC strategy. We take into account the impact of hardware distortions resulting in residual self-interferenc…
The key advantage of successive relaying (SR) networks is their ability to mimic the full-duplex (FD) operation with half-duplex (HD) relays. However, the main challenge that comes with such schemes is the associated inter-relay interference (IRI). In this work, we propose a reconfigurable intelligent surface (RIS)-enhanced SR network, where one RIS is deployed near each of the two relay nodes to provide spatial suppression of IRI, and to maximize the gain of desired signals. The resultant max-min optimization problem with joint phase-shift design for both RISs is first tackled via the semidef…
On the Achievable Diversity-Multiplexing Tradeoffs in Half-Duplex Cooperative Channels
在本文中,我们提出了新的合作传输协议的延迟有限的相干衰落信道组成的N(半双工和单天线)的合作伙伴和一个小区站点。在我们的工作中,我们区分中继,合作广播(下行链路),合作多址(上行链路)信道。对于中继信道,我们研究了两类合作方案,即放大和转发(AF)协议和解码和转发(DF)协议。对于第一类,我们建立了一个上限上实现的分集复用的权衡与一个单一的中继。然后,我们构建了一个新的AF协议,达到这个上限。该算法扩展到一般情况下,N-1中继,它被证明优于空时编码协议的Laneman和Warenell,而不需要解码/编码的中继。对于这类DF协议,我们提出了一种动态解码转发(DDF)协议,该协议在复用增益0 < r < 1/N的情况下实现了最优折衷。此外,与一个单一的中继,DDF协议示出占主导地位的AF协议的所有复用增益的类。DDF协议的优越性在协作广播信道中表现得更为明显。这种情况是相反的合作多址信道,我们提出了一个新的AF协议,实现了所有复用增益的最佳权衡。在这三种情况下,所提出的协议的一个显著特征是它们不依赖于正交子空间,从而允许更有效地利用资源。事实上,使用我们的研究结果可以说,以前提出的协议的次优源于他们使用的正交子空间,而不是半双工约束。
This paper considers secure communication in buffer-aided cooperative wireless networks in the presence of one eavesdropper, which can intercept the data transmission from both the source and relay nodes. A new max-ratio relaying protocol is proposed, in which different relays are chosen for reception and transmission according to the ratio of the legitimate channels to the eavesdropper channels, so that the relay selected for reception and the relay selected for transmission can receive and transmit at the same time. It is worth noting that the relay employs a randomize-and-forward (RF) strat…
In this report, we summarize the end-to-end signal-to-noise ratio and the rate of half-duplex, full-duplex, amplify-and-forward, and decode-and-forward relay-aided communications, and well as the signal-to-noise ratio and the rate of the emerging technology known as reconfigurable intelligent surfaces.