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ICT for Health: Networks, standards and innovation




                                  Table 1 – Backbone network topology vs sparse network topology

                             Network performance                  Reduced network   Backbone
                             Node degree                                3.81          4.03
                             Coefficient of variation (link margin-(dBm))  2.83         3.86
                             Shortest distance (km)                     12.88         12.31
                             Path multiplicity                           2             1


           9, the network backbone decreased towards a convergence.           7.  CONCLUSION
           However, the decrease is slower and hence the backbone size
           converges to a higher number of nodes.             In this paper, design challenges expected to be met when
                                                              designing mesh networks using opportunistic access to the
           Considering the effect of shortest distance between nodes,  white space frequencies were explored and discussed. Dense
           Figure 11 shows a different trend. The size of backbone  network topology was highlighted as one of the design
           increased in general until it converges to a maximum.  challenges that network planners and designers in white space
                                                              frequencies will face and the paper focused on addressing
                                                              this challenge. A link-based topology reduction algorithm
           The conclusions drawn from the three graphs depicting  has been developed to reduce a dense mesh network topology
           impact of the design parameters on the backbone size are  designed in white space frequencies into sparse mesh network
           as follows: the backbone size is affected by change of each of  topology and a network optimization function based on
           the three parameters. These results also reveal that the node  three metrics has been developed to introduce hierarchical
           degree has a much higher positive influence on the backbone  backbone-based network topology from the sparse network
           size, leading to smaller backbones, which can allow networks  topology. Performance evaluation on the designs were carried
           to scale while keeping the size of the backbone constant and  out and the results show that the designs can guide network
           smaller.                                           engineers to select the most relevant performance metrics
                                                              during a network feasibility study in white space frequencies,
                                                              aimed at guiding the implementation process.


                                                                               REFERENCES
                                                               [1] P. Cui, Y. Dong, H. Liu, D. Rajan, E. Olinick, and
                                                                  J. Camp, “Whitemesh: Leveraging white spaces in
                                                                  wireless mesh networks,” In 2016 14th International
                                                                  Symposium on Modeling and Optimization in Mobile,
                                                                  Ad Hoc, and Wireless Networks (WiOpt), pp. 1-7. IEEE,
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                                                               [2] L. Uscher-Pines, K. Bouskill, J. Sousa, M. Shen, and
                                                                  S.H. Fischer. Experiences of Medicaid Programs and
                                                                  Health Centers in Implementing Telehealth. RAND,

                  Figure 10 – Impact of β on backbone size        2019.
                                                               [3] The App Association, “Tuning into Telehealth: How
                                                                  TV White Spaces Can Help Mississippi Tackle the
                                                                  Diabetes Epidemic,” 2017. http://actonline.org/2017/
                                                                  07/20/tuning-into-telehealth-how-tv-white-spaces-
                                                                  can-help-mississippi-tackle-the-diabetes-epidemic/.
                                                               [4] A. Chavez, R. Littman-Quinn, K. Ndlovu, and C.L.
                                                                  Kovarik, “Using TV white space spectrum to practise
                                                                  telemedicine:  A promising technology to enhance
                                                                  broadband internet connectivity within healthcare
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                                                               [5] J. Zhao, H. Zheng, and G. Yang, “Distributed
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                  Figure 11 – Impact of λ on backbone size        In First IEEE International Symposium on New





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