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Wireless Local and Wireless Personal Area Network Communication in Industrial Environments
Published in Richard Zurawski, Networked Embedded Systems, 2017
This chapter investigates the performances of WLAN and WPAN technologies from a radio network perspective. The radio network perspective includes that not only the hazards of the physical transmission (echoes, etc.) impact the performance but also the existence of other networks transmitting in the same space and frequency range. That means that in addition to the system inherent parameters also factors like unit density, traffic demand, mobility, environmental changes during deployment, interference, frequency range, etc. play a role. Thus both, the individual link performance and the overall network capacity, should be optimized. Higher protocol layers (e.g., TCP/IP, Fieldbus systems) are not part of the investigations. For an introduction into that topic please refer to [WMW05].
Green Communications and Networking
Published in Matthew N. O. Sadiku, Emerging Green Technologies, 2020
Cellular networks: A cellular network is a radio network distributed over land areas known as cells, each served by at least one base station. A typical cellular network consists of three main elements: a core network that takes care of switching, base stations providing radio frequency interface, and the mobile terminals used in making voice or data connections [20]. The cellular network is the largest factor contributing to the mobile industry's energy consumption. As a result, energy efficiency in cellular networks has been a growing concern for cellular operators. Green communication technologies are widely preferred and deployed for achieving energy efficiency.
Outage and throughput performance of a multihop network with an adaptive power splitting-based energy harvesting
Published in International Journal of Electronics Letters, 2021
S. Mondal, S. D. Roy, S. Kundu
Radio frequency (RF) based energy harvesting technique has drawn extensive attention in battery limited wireless system to prolong the life time of sensor node. In Zheng et al. (2016), the authors have considered direct data transmission from secondary user transmitter to secondary user receiver, where secondary transmitter is powered by harvested energy from RF signal of primary user transmitter in a cognitive radio network (CRN) and investigate a trade-off between harvesting and throughput. The coverage area of a network can be extended and performance can be improved using the concept of relay assisted energy harvesting network (Zheng et al., 2016; Nasir et al., 2013). In simultaneous wireless information and power transfer (SWIPT), a relay node can harvest energy from RF signal of the preceding node and also extract information from same signal either in time switching based relaying scheme or in power splitting based relaying scheme (PSR) (Nasir et al., 2013). In Nasir et al. (2013), the authors have used an energy harvesting technique to power up the intermediate relay nodes in SWIPT mode.
A Novel MAC Protocol with Fusion Center and Adaptive Full-Duplex Communication for Cognitive Radio Networks
Published in IETE Journal of Research, 2021
Appala Raju Uppala, C. Venkata Narasimhulu, K. Satya Prasad
In [27], the developers proposed an FD Transmit Receive (FDTR) system. The technique projected utilized the cooperative sensing and bidirectional FD broadcasting or transmission FD communication of the cognitive radio network. The collision duration gets reduced when there is a utility of the asynchronous transmission at the unlicensed nodes. If the primary signal is not strong enough for identifying the FDTR mode, then this method experiences a long period of collision. The algorithms of Slotted Aloha (S-Aloha) and Reserved Aloha (R-Aloha) are presented in [20]. The major drawback of these algorithms is the high count of collisions due to the random access of channels. The energy efficiency of the process of CSS also degrades when collisions occur at the data transmission phase.
Performance of a multihop cognitive radio network with diversity under imperfect CSI
Published in International Journal of Electronics Letters, 2023
S. Mondal, D. Bepari, S. Biswas
A multihop cognitive radio network with a primary transmitter-receiver pair and betray operated secondary nodes has been considered, as shown in Figure 1. The secondary nodes are allowed in the primary spectrum simultaneously maintaining the interference at the primary receiver introduced by secondary transmitter is below a predefined threshold level. A relay node transmits a signal following a half-duplex communication protocol. The node transmits signal to destination node via number of intermediate relay nodes maintaining , the interference constraint of the primary system. The source sends a signal to the next immediate node, the node decodes the signal and forwards it to the next node. However, when a relay node fails to decode the received signal, it stops further signal transmission. This process continues till the signal reaches the destination. To to fulfil the QoS requirement, the SINR of the signal transmitted by the previous secondary node has to be greater than , the SINR threshold. Hence, to make a successful transmission, a node has to maintain both the QoS and interference constraints. In our model, each node combines signals from preceding node and previous to preceding node following either MRC or SC diversity technique.