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Relaying Protocols for In-Home PLC
Published in Lars T. Berger, Andreas Schwager, Pascal Pagani, Daniel M. Schneider, MIMO Power Line Communications, 2017
Salvatore D’Alessandro, Andrea M. Tonello
In relay networks, the communication between the source and the destination nodes is helped by the use of one or more relays. More precisely, the relay receives the signal addressed to the destination node, processes it according to a given relay protocol and forwards it to the destination. The destination node combines the signals received from the source and from the relay. Many relay protocols have been proposed in the literature [4]: amplify and forward (AF), classic multi-hop, compress and forward (CF), decode and forward (DF) and multipath DF. In the following, we focus on AF and DF. In AF, the relay only amplifies and forwards the received signal to the destination, whereas in DF, the relays decode and re-encode the signal before forwarding it. AF and DF have been studied considering both half-duplex and full-duplex transmission, namely, a node can only transmit or receive at one time, or it can transmit and receive simultaneously. In the rest of this chapter, we consider the half-duplex modality, since full duplex is often not possible to be implemented due to high complexity [4].
Adaptive Modulation, Adaptive Power Allocation, and Adaptive Medium Access
Published in Mohamed Ibnkahla, Wireless Sensor Networks, 2017
When there are multiple nodes in the network, the communication between nodes can be categorized into two types: (1) multihop relay networks that transmit the source data to the destination through relay nodes, and (2) multiple-link networks where multiple sources and destinations exist in the network and each source transmits data to its destination independently. Here we investigate the energy consumption using link adaptation in two-link relay networks.
User-relay assisted cellular networks with multiple antennas
Published in International Journal of Electronics, 2019
The system performance depends on the number of relay candidates in relay-assisted networks. For fixed relay networks the number of relay candidates is limited so the relay usability is also limited. However, this case is not valid for the user-relay assisted networks since the number of relays scales with the number of users. In these networks, signalling overhead may be a problem when all UEs are selected as the possible relay candidates (Han et al., 2009; Kim, Lee, Son, Song, & Chong, 2012; Ng & Yu, 2007). In this work, to overcome this problem and to have lower computational complexity relay candidates are selected using a restricted area which has a radius (Basturk & Ozbek, 2015, 2016a, 2016b; Papadogiannis, Alexandropoulos, Burr, & Grace, 2012), as shown in Figure 1.