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Service Deployment
Published in Krzysztof W. Kolodziej, Johan Hjelm, Local Positioning Systems, 2017
Krzysztof W. Kolodziej, Johan Hjelm
A signal strength model or radio/coverage map shows the fundamental signal propagation and related effects, like multipath and shading, for a specific environment. It is mainly useful for network planning and the analysis of signal attenuation by physical obstruction. Moreover, it serves as a database for the empirical verification of the signal propagation model. In order to convert received signal strength indicator (RSSI) values to a range estimate to be used with triangulation methods, it is necessary to use an appropriate signal propagation model. Constructing the radio map requires deciding the granularity of the readings (the distance between every reading), how many readings are needed to obtain a realistic average, and what is the best time to do the measurement (nighttime, daytime, or both).
An Introduction To Digital TV
Published in Steven Morris, Anthony Smith-Chaigneau, Interactive TV Standards, 2012
Steven Morris, Anthony Smith-Chaigneau
In an IP network, we can do this using checksums and acknowledgments to retransmit packets if one of them is corrupted. In a broadcast network, this is not practical. There may not be any way for the receiver to tell the transmitter about an error. Even if there were, the transmitter might not be able to resend the data in time. In addition, different physical locations will have different patterns of interference. For instance, electronic equipment may produce interference in one location but not another, or weather patterns may interfere with broadcasts in one parts of a satellite’s coverage area but not another. If we were resending data, this would make it necessary to resend different packets for different receivers. In a busy environment, in which a transmitter may serve hundreds of thousands of households, this is simply not possible.
DVB-H Systems and Receivers
Published in Borko Furht, Syed Ahson, Handbook of Mobile Broadcasting, 2008
F. Boronat, R. Llorente, J. Lloret, D. Vicente
A typical DVB-SH system is based on a hybrid architecture combining a satellite component and a CGC consisting of terrestrial repeaters fed by a broadcast distribution network (see figure 21.6). The repeaters could be used as broadcast infrastructure transmitters (to complement reception in areas where satellite reception is difficult), as personal gap fillers of limited coverage providing local on-frequency retransmission or frequency conversion, or as mobile broadcast infrastructure transmitters.
Assessment framework for Proof of Concept (PoC) in Industry 4.0 – an interoperability approach
Published in International Journal of Computer Integrated Manufacturing, 2023
Luiz Felipe Pierin Ramos, Eduardo de Freitas Rocha Loures, Fernando Deschamps, André Luiz Alcântara Castilho Venâncio, Gabriel da Silva Serapião Leal
The Capacity pillar refers to the data rate or daily baud rate in bytes. High capacity may be associated with industries and applications working with up to 50% of the information requiring monitoring. For low capacity, this Figure is capped at 20%. Consumption refers to the battery lifetime based on the application case. A battery may have a minimum lifetime of 3 and a maximum lifetime of 10 years. A variable that interferes directly in the consumption is latency that is inversely proportional to battery lifetime. Coverage may be classified as indoor and/or outdoor, depending on the context where the equipment will be placed. High coverage includes long reach in outdoor areas and in indoor areas such as underground spaces, parking lots or inside buildings where there are obstacles and sources of interference. Finally, and probably the most important in terms of decision-making, there is the Cost. This parameter determines how significant the introduction of the technology will be and the consequent impact in the application site. Among the possible LPWAN costs, the module and network infrastructure are standouts (Frost & Sullivan 2017).
Research on coverage monitoring technology of subsea production system based on wireless sensor network
Published in Australian Journal of Mechanical Engineering, 2023
Si Zhang, Meiqiu Li, Chong Zhao, Ye Tian, Bixia Wang
Wireless Sensor Network (WSN) is a network covered by sensor nodes deployed in the area to be monitored through self-organisation(Khediri et al. 2020; Singh, Kaur, and Singh 2020). In WSN, nodes all have the function of data transmission. According to the design of different network functions, nodes can accomplish different work tasks. As shown in Figure 3, it represents a basic WSN structure. The nodes that cover the region to be monitored transmit the collected information and data to the terminal or observer in a cooperative manner. In order to complete the specified monitoring tasks, a large number of nodes are deployed in the region to be monitored. Therefore, the key to improve the wireless transmission efficiency is how to realise the coverage of the area through a more effective node deployment method.
Multi-robot formation based on RSSI power level and radiation pattern
Published in International Journal of Systems Science, 2022
E. G. Hernandez-Martinez, Jaime González-Sierra, Eduardo Alvarez-Guzman, Guillermo Fernandez-Anaya, Enrique D. Ferreira-Vazquez, José-Job Flores-Godoy
On the other hand, a Wireless Sensor Network (WSN) is defined as a set of wireless devices or WS nodes, strategically located in order to transmit messages in a collaborative manner (Ayaz et al., 2018) which is a useful way to cover large areas using a set of low-cost and low-level power nodes instead of a unique high power wireless transmitter (Movassaghi et al., 2014). In this work, the ‘wireless coverage’ is defined from a communication system point of view, as a physical area where it is still possible to achieve useful communication link between two or more devices (Kumar & Lobiyal, 2013). WSNs have been useful in applications like rescue operations (Mandal et al., 2013), monitoring of pollution (Lalitta et al., 2011), emergency setups in contingencies of natural disasters (Budianto et al., 2011), among others. The wireless communication device antennas in each node must be oriented according to its radiation pattern, which is not omnidirectional in most cases. Thus the connectivity of the network depends on the inter-node distances and the antenna radiation pattern orientation while the power transmission and reception of the antenna can be affected by obstacles between the nodes, multi-path interference, other sources noise, and the changes of available energy at the sensors.