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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Performance analysis of NB-IOT network for patients monitoring in rural areas.</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Athanase M.Atchome</string-name>
          <email>matchome@finances.bj</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Frantz U. TOSSA</string-name>
          <email>frantztossa@gmail.com</email>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Thierry O. Edoh</string-name>
          <xref ref-type="aff" rid="aff6">6</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Marc K. ASSOGBA</string-name>
          <email>mkokouassogba@yahoo.fr</email>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Eugene EZIN</string-name>
          <email>eugene.ezin@gmail.com</email>
          <xref ref-type="aff" rid="aff4">4</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Antoine C. Vianou</string-name>
          <email>avianou@yahoo.fr</email>
          <xref ref-type="aff" rid="aff3">3</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Pierre GOUTON</string-name>
          <email>pgouton@u-bourgogne.fr</email>
          <xref ref-type="aff" rid="aff5">5</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Ecole Doctorale des Sciences De l'Ingnieur, Universite ́ d'Abomey-Calavi</institution>
          ,
          <addr-line>Abomey-Calavi, Be ́nin</addr-line>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Ecole Doctorale des Sciences De l'Ingnieur, Universite ́ d'Abomey-Calavi</institution>
          ,
          <addr-line>Abomey-Calavi, Be ́nin</addr-line>
        </aff>
        <aff id="aff2">
          <label>2</label>
          <institution>Ecole Doctorale des Sciences De l'Ingnieur, Universite ́ d'Abomey-Calavi</institution>
          ,
          <addr-line>Abomey-Calavi, Be ́nin</addr-line>
        </aff>
        <aff id="aff3">
          <label>3</label>
          <institution>Ecole Doctorale des Sciences De l'Ingnieur, Universite ́ d'Abomey-Calavi</institution>
          ,
          <addr-line>Abomey-Calavi, Be ́nin</addr-line>
        </aff>
        <aff id="aff4">
          <label>4</label>
          <institution>IFRI-UAC, Universite ́ d'Abomey-Calavi</institution>
          ,
          <addr-line>Abomey-Calavi, Be ́nin</addr-line>
        </aff>
        <aff id="aff5">
          <label>5</label>
          <institution>Imagerie et Vision Artificielle, Universite ́ de Bourgogne</institution>
          ,
          <addr-line>Bourgogne</addr-line>
          ,
          <country country="FR">France</country>
        </aff>
        <aff id="aff6">
          <label>6</label>
          <institution>RFW-Universitt of Bonn</institution>
          ,
          <addr-line>Technische Universitt Mnchen, munich, Germany, 0000-0002-7390-3396</addr-line>
        </aff>
      </contrib-group>
      <pub-date>
        <year>2018</year>
      </pub-date>
      <abstract>
        <p>-Medical surveillance is based on continuous monitoring of the patients vital parameters. The control of vital signs is essential in different cases. Actually, in the case of criticals healths issues (road or traffic accident; Pregnancy and pregnancy-related complication like blood pressure, foetal heart rate, etc...) vitals parameters need to be continually measured. Imagine the case where the patient is living in a rural area or remote area with poor health infrastructure. That kind of situation needs the involvement of news technologies (telemedicine, IoT), technics to help to overcome the medical service delivery issues. Base on this background and due to the technologies issues and limitations in some area or region the authors had proposed a new technology to support the medical service delivery at a remote area. The proposed technology consisted of Narrowband Internet of Things (NB-IoT). Its a new technology which provides longrange communications, low data rate for sensors with reduced device processing complexity and long battery lifetime.This paper aims to investigate the realistic performance of NBIoT in terms of effective throughput and patient served per cell in the healthcare monitoring system in a rural area with in-band and stand-alone deployment. Index Terms-Narrowband Internet of Things (NB-IoT); Healthcare monitoring; throughput; latency; device capacity; system-level analysis.</p>
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>I. INTRODUCTION</title>
      <p>
        The last quarter century has been a period of huge change
and progress in developing countries. Never the less this
impressive progress, health access remains limited for many
people especially, in rural area and slums in the large city.
In fact, in Low and Middle-Income Countries (LMIC), the
Identify applicable funding agency here. If none, delete this.
health sector is facing some challenges ( lack of skills, but
also a shortage of health personnel and even worse, a lack of
health centres). These issues are more several in the rural area.
This compromises the provision, continuity and availability of
care and services for the habitats of these areas. As a result,
the populations in the areas face inadequate health care due to
shortage or poor distribution of financial and human resources
and a shortage of specialized services. Specialists often do not
have enough ”critical mass” of patients to be economically
profitable to serve a region that is both sparsely populated
and far away. The situation can be particularly difficult for
patients with certain diseases, or for the elderly. Information
and communication technology solutions, such as e-health,
telemedicine, etc ... can be seen as ways to bridge the digital
divide between rural and urban health centers and address
deficiencies health sector in rural areas[
        <xref ref-type="bibr" rid="ref6">6</xref>
        ]. The term ”rural”
can be defined in a variety of ways, depending for example
on the density of the population or geographical location. For
example, the US Census Bureau defines rural as what is not
urban - that is, after defining individual urban areas, what
remains is rural [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ]. In this article, we propose a network of
NB-IOT sensors to coordinate the follow-up of the patients in
a rural area of Benin and this from a health centre installed in
this zone. The main contributions and results of this document
are:
      </p>
      <p>Design a tractable wireless sensor network (NB-IOT)
system to coordinate patient follow-up in a rural area of
Benin;</p>
    </sec>
    <sec id="sec-2">
      <title>Remotely monitor the condition of critical patients; Enable the automatic collection of multi modal data, storage and processing using a single system over time; Increase the responsiveness of the nursing staff.</title>
    </sec>
    <sec id="sec-3">
      <title>II. NB-IOT OVERVIEW AND BACKGROUND</title>
      <p>
        To suport the Internet of Things, a narrowband system
based on Long Term Evolution (LTE) is introduced in 3rd
Generation Partnership Project (3GPP) [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ][
        <xref ref-type="bibr" rid="ref2">2</xref>
        ]. This system is
named Narrowband Internet of Things (NB-IoT), and can be
deployed in three different operation modes [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ]:
1) stand-alone ;
2) in-band;
3) within the guard-band of an existing LTE carrier.
In the stand-alone operation mode, NB-IoT can occupy one
GSM channel (200 kHz) while for in-band and guard-band
operation modes, it will use one physical resource block
of LTE (180 kHz). The targets of NB-IoT include low-cost
devices, high coverage, long device battery life and massive
capacity [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ]. Although the signaling and control channels for
NB-IoT are new, its design exploits the basic features of LTE.
Furthermore, in NB-IoT, frequency division duplexing (FDD)
half duplex type-B is chosen as the duplex mode whereas
legacy LTE also supports full duplex mode [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ], and unlike
LTE, NB-IoT has two physical signals and three physical
channels [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ] which are as follows:
      </p>
      <p>Narrowband reference signal (NRS);
Narrowband primary and secondary synchronization
signals (NPSS and NSSS);
Narrowband physical downlink control channel
(NPDCCH);
Narrowband physical downlink shared channel
(NPDSCH).</p>
      <p>In the uplink, NB-IoT support both single-and multi-tone
transmissions. Furthermore, in NB-IoT uplink, a new resource
mapping unit is defined as a resource unit (RU). RU is a
combination of a number of subcarrier (frequency domain)
and a number of slots (time domain). For the uplink, NB-IoT
has one physical signal and two physical channels which are
as follows:</p>
      <p>Demodulation reference signal (DMRS);
Narrowband physical random access channel (NPRACH);
Narrowband Uplink Shared Channel (NPUSCH).</p>
      <p>
        NB-IoT has been developed by 3GPP to enable a wide range
of cellular devices and services [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ]. Key target applications
include smart cities, personal IoT applications, smart grids and
meters, logistics, industrial monitoring, agriculture, and more.
In this work, we used the NB-IoT application in the Wireless
Remote Monitoring System (WBAN).
      </p>
      <p>III. APPLICATION USE-CASE: HEALTH CARE</p>
      <p>MONITORING SYSTEM</p>
      <p>In hospitals, the temperature of a patients body, for instance,
need to be monitored constantly, which is generally made by
the staff members of the hospital. They notice the temperature
of the patients body constantly and keeps a record of it.
Health monitoring means monitoring a person to identify any
changes in his or her health status because of exposure to
certain health hazards arising from the conduct of the business
or undertaking (GRWM Regulations). Health monitoring is a
way to check if the health of workers is being harmed from
exposure to hazards while carrying out work, and aims to
detect early signs of ill-health or disease. Health monitoring can
show if control measures are working effectively. Monitoring
does not replace the need for control measures to minimise or
prevent exposure. Nowadays, health care sensors are playing
an essential role in hospitals. The patient monitoring system
is one of the major developments because of its innovative
technology. An automatic wireless health monitoring system
is used to measure the patients body temperature and heartbeat
by using embedded technology.</p>
      <p>
        The use of NB-IoT allows the use of an already deployed
cellular base station and covers all facilities in
underdeveloped countries, eg rural hospitals. NB-IoT offers end-user
terminals (eg sensor nodes) a long service life. However, each
application is characterized by different coverage requirements
and performance requirements in terms of tattoo demand or
latency. For example, health usually requires monitoring of
perspiration, respiratory rate, body temperature, pulse and
blood pressure, etc. Data rates of up to 2 Kbps per sensor may
be required. In our design model of the health care monitoring
system, we consider the single-sensor nodes. In this design,
each sensor node, such as a temperature sensor, a respiratory
rate sensor, etc., is considered an individual node and each
node has its own transmission module. Therefore, each node
transmits data to the central processing unit through the eNB
with latency and data rate requirements [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ]. In this design, for
each patient, several transmission links are needed with the
base station. The traffic in the health care monitoring system
is based on multiple sensors with different sizes of information
packets and time interval. In our analysis, we assume the case
of a critical patient requiring constant surveillance. All sensors
communicate with the NB-IoT base station directly for each
patient.In this context, all patient data is sent by the sensors
carried by the patients to the treatment center via the base
station. These data are processed and health staff such as
general practitioners, specialists, nurses, carer can consult, use
in real time. Fig 1. shows the proposed model.
      </p>
      <p>IV. METHODOLOGY, DATA AND SYSTEM MODEL</p>
      <p>To conduct the performance analysis, we have considered
both in-band and standalone deployments of NB-IoT with a
bandwidth of 180 kHz in a typical LTE. The scenario is a
regular grid of tri-sector sites with inter-site distance of 1732m.
In-band mode, for instances where cellular services are present
and NB-IoT is positioned in the LTE carrier sharing LTE
resources; this mode of operation is perhaps the more
costeffective and seamless for mobile operators since it does not
require any hardware changes of the radio access network,
and efficiently uses spectrum resources for LTE or NB-IoT
services based on demand from mobile users or devices. In
Standalone mode, for instances where cellular services are not
present or are decommissioned to make narrowband spectrum
available, which is the case of cellular GSM; by reframing
one or more GSM carriers to carry NB-IoT traffic, operators
can ensure a smooth transition to LTE for massive machine
type communication. The Fig 2 illustrate the deployment of
in-band and Stand Alone.</p>
      <p>
        The other simulation assumptions that closely follows are
presented in Table1. The full 180 kHz bandwidth, i.e. 12
subcarriers at 15 kHz subcarrier spacing in both downlink and
uplink, is used for the analysis. For uplink, this is known to
perform worse than single tone e.g. 3.75 kHz or 15 kHz, so
the achieved performance in this study yields lower bounds as
compared to what can be achieved with single tone NB-IoT
systems and it is more realistic assumption to investigate
NB-IoT uplink performance[
        <xref ref-type="bibr" rid="ref3">3</xref>
        ] . The data rate Ri;n for a
node i when the nth PRB is assigned is given by:
Ri;n = Blog2(1 + SIN Ri;n)
(1)
where B is the assigned transmission bandwidth and SIN Ri;n
is the signal-to-interference-plus-noise (SINR) for node i on
nth PRB and is given as:
      </p>
      <p>SIN Ri;n =</p>
      <p>
        Pnhi;n
Ii;n + N0
(2)
where Pn is the transmit power and hi;n is the channel
gain between node i and the base station on the nth PRB.
Ii;n is the interference experienced by node i and is assumed
to be negligible in our analysis. N0 is the noise power
spectral density. Based on the SINR, the corresponding MCL
is computed. The relationship between SINR and MCL is
given as [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ]:
      </p>
      <p>T argetSIN R = Txpower + 174
N oisef igure
(3)
10log10(B)</p>
      <p>M CL</p>
    </sec>
    <sec id="sec-4">
      <title>The path loss is given by:</title>
      <p>P athLoss = I + 37:6log10(R)
(4)
R in Kilometers with I=120.9 for the 900 Mhz</p>
      <p>
        The inter-arrival time is distributed over three categories
of periodic transmissions with constant inter-arrival times of
1 day, 2 hours, 1 hour and 30 minutes. Based on [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ],the
respective proportions of devices are 46%, 47%, 15%, and
5%. The average arrival rate of reports per device is:
      </p>
      <p>In this section, we evaluate the performance of the NB-IoT
system-level system using Monte Carlo simulations in terms
of actual throughput and the number of devices supported.
With the parameters shown in Table 1, the simulation is run
for band and standalone deployments for more than 750
random samples. Figure 3 illustrates the cumulative distribution
function (CDF) of the average effective flow in different strip
and stand-alone deployments. The actual rate is defined as
the number of bits of information transmitted per second
with all the control information headers. The tape deployment
performance in terms of battery life is significantly degraded
due to the presence of LTE control information and the</p>
      <p>TABLE I</p>
      <p>SIMULATION ASSUMPTION
assumptions
different interferences due to the two coexisting systems.
Figure 4 shows the average number of patients that can be
treated in different deployment scenarios. The result is that
autonomous deployment is an important way to dramatically
improve the flow and number of patients in care.</p>
    </sec>
    <sec id="sec-5">
      <title>VI. CONCLUSION AND PERSPECTIVES</title>
      <p>In this article, we presented a detailed performance analysis
specific to a NB-IoT application for a rural health care
surveillance system. The analysis carried out shows that with
the autonomous deployment, one observes a significant gain in
flow and a large number of patients per cell compared to the
deployment in band. From these results, we can conclude that
the NB-IoT technology is better suited for monitoring patients
in rural areas, due to precarious conditions such as lack of
electricity and medical infrastructure. Based on the results of
this work, we can in terms of perspectives, work to precisely
determine the geolocation of patients and evaluate different
resource management strategies in NB-IoT rural systems.</p>
    </sec>
  </body>
  <back>
    <ref-list>
      <ref id="ref1">
        <mixed-citation>
          <source>[1] 3GPP TR 45.820</source>
          .
          <article-title>Cellular System Support for Ultra Low Complexity and Low Throughput Internet of Things</article-title>
          .
          <source>Technical Report</source>
          ;
          <year>2015</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref2">
        <mixed-citation>
          <article-title>[2] 3GPP R1157398</article-title>
          .
          <article-title>NB-IoT - System level evaluation and comparison - standalone</article-title>
          .
          <source>Technical Report; Ericsson</source>
          ;
          <year>2015</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref3">
        <mixed-citation>
          <article-title>[3] 3GPP R1157248</article-title>
          .
          <article-title>NB-IoT Capacity evaluation</article-title>
          .
          <source>Technical Report; Nokia Networks</source>
          ;
          <year>2015</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref4">
        <mixed-citation>
          [4]
          <string-name>
            <surname>Persia</surname>
            <given-names>S</given-names>
          </string-name>
          , Rea L.
          <article-title>Next generation M2M Cellular Networks: LTEMTC and NB-IoT capacity analysis for Smart Grids applications</article-title>
          .
          <source>AEIT International Annual Conference (AEIT)</source>
          <year>2016</year>
          ; p.
          <fpage>16</fpage>
          .
        </mixed-citation>
      </ref>
      <ref id="ref5">
        <mixed-citation>
          [5]
          <string-name>
            <surname>Berliandhy</surname>
            <given-names>IE</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Rizal</surname>
            <given-names>A</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Hadiyoso</surname>
            <given-names>S</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Febyarto</surname>
            <given-names>R.</given-names>
          </string-name>
          <article-title>A multiuser vital sign monitoring system using ZigBee wireless sensor network</article-title>
          .
          <source>International Conference on Control, Electronics, Renewable Energy and Communications (ICCEREC)</source>
          <year>2016</year>
          ; p.
          <fpage>136140</fpage>
          .
        </mixed-citation>
      </ref>
      <ref id="ref6">
        <mixed-citation>
          [6]
          <string-name>
            <surname>Nkqubela</surname>
            <given-names>L Ruxwana</given-names>
          </string-name>
          , Marlien E Herselman and
          <string-name>
            <given-names>D</given-names>
            <surname>Pieter</surname>
          </string-name>
          Conradie, ”
          <article-title>ICT applications as e-health solutions in rural healthcare in the Eastern Cape Province of South Africa”</article-title>
          ,
          <source>HEALTH INFORMATION MANAGEMENT JOURNAL</source>
          Vol
          <volume>39</volume>
          No 1
          <issue>2010 ISSN</issue>
          <year>1833</year>
          -
          <volume>3583</volume>
          (PRINT)
          <article-title>ISSN 1833-3575 (ONLINE</article-title>
          )
        </mixed-citation>
      </ref>
      <ref id="ref7">
        <mixed-citation>
          [7]
          <string-name>
            <given-names>Michael</given-names>
            <surname>Ratcliffe</surname>
          </string-name>
          , Charlynn Burd, Kelly Holder, and Alison Fields, ”
          <article-title>Defining Rural at the U.S. Census Bureau”</article-title>
          , in American Community Survey and
          <string-name>
            <given-names>Geography</given-names>
            <surname>Brief</surname>
          </string-name>
          , Issued December 2016
        </mixed-citation>
      </ref>
      <ref id="ref8">
        <mixed-citation>
          [8]
          <string-name>
            <given-names>Rapeepat</given-names>
            <surname>Ratasuk</surname>
          </string-name>
          , Benny Vejlgaard,
          <article-title>Nitin Mangalvedhe and Amitava Ghosh, ”NB-IoT system for M2M communication”</article-title>
          ,
          <source>in IEEE Wireless Communications and Networking Conference</source>
          ,
          <year>2016</year>
        </mixed-citation>
      </ref>
      <ref id="ref9">
        <mixed-citation>
          [9]
          <string-name>
            <given-names>Hassan</given-names>
            <surname>Malik</surname>
          </string-name>
          , Muhammad Mahtab Alam, Yannick Le Moullec and Alar Kuusik, ”
          <article-title>NarrowBand-IoT Performance Analysis for Healthcare Applications” 9th</article-title>
          <source>International Conference on Ambient Systems, Networks and Technologies, ANT-2018 and the 8th International Conference on Sustainable Energy Information Technology, SEIT</source>
          <year>2018</year>
          ,
          <volume>8</volume>
          -11 May,
          <year>2018</year>
          , Porto, Portugal
        </mixed-citation>
      </ref>
      <ref id="ref10">
        <mixed-citation>
          [10]
          <string-name>
            <surname>Usman</surname>
            <given-names>Raza</given-names>
          </string-name>
          , Parag Kulkarni, and Mahesh Sooriyabandara ”
          <article-title>Low Power Wide Area Networks: An Overview”</article-title>
          ,
          <source>IEEE Communications Surveys &amp; Tutorials</source>
          , 2017
        </mixed-citation>
      </ref>
      <ref id="ref11">
        <mixed-citation>
          [11]
          <string-name>
            <given-names>Y.-P.</given-names>
            <surname>Eric</surname>
          </string-name>
          <string-name>
            <given-names>Wang</given-names>
            ,
            <surname>Xingqin Lin</surname>
          </string-name>
          , Ansuman Adhikary, Asbjrn Grvlen, Yutao Sui,Yufei Blankenship,
          <article-title>Johan Bergman and Hazhir S. Razaghi, ”A Primer on 3GPP Narrowband Internet of Things (NB-IoT)” IEEE Communications Magazine</article-title>
          ( Volume:
          <volume>55</volume>
          , Issue: 3 ,
          <year>March 2017</year>
          )
        </mixed-citation>
      </ref>
      <ref id="ref12">
        <mixed-citation>
          [12]
          <string-name>
            <surname>Alexandros-Apostolos</surname>
            <given-names>A</given-names>
          </string-name>
          .
          <string-name>
            <surname>Boulogeorgos</surname>
            ,
            <given-names>Panagiotis D.</given-names>
          </string-name>
          <string-name>
            <surname>Diamantoulakis</surname>
          </string-name>
          , George K. Karagiannidis, ”
          <article-title>Low Power Wide Area Networks (LPWANs) for Internet of Things (IoT) Applications: Research Challenges and Future Trends” Published 2016 in ArXiv</article-title>
        </mixed-citation>
      </ref>
    </ref-list>
  </back>
</article>