E. Nolan and M. Y. Kelly, 2015) and Long Term Evo-
lution (LTE) Machine-Type-Communications (MTC)
(3GPP, 2014) or NB-IoT are being developed to be
integrated with existing 2G, 3G and LTE networks.
For these technologies, the aspects of network up-
grade are being clarified; it may be as simple as a
remote software upgrade but more likely hardware
changes will be required, but with no modifications
to the needed antennas. In contrast, proprietary tech-
nologies like SIGFOX, On-Ramp and Semtech (G.
Margelis and R. Piechocki and D. Kaleshi and P.
Thomas, 2015), require a purpose-built network to de-
ploy their services. For the existing operators, this
means still using existing sites, but additional integra-
tion and infrastructure, including antenna and base-
station equipment, should be required. For a new op-
erator entering in this market, the green field approach
is possible, although new operators should perform
agreements with the existent ones in order to perform
site-sharing and reduce costs.
Whatever the case, sites have to be chosen among
a (internal or external) site list, in order to fulfil cover-
age and capacity requirements. Moreover, when con-
sidering LPWA technologies, often base-station re-
dundancy must be met, i.e., coverage requirements
should be set not only for the serving base-station but
also for neighbour base-stations, which should pro-
vide redundant coverage. This assures that the LPWA
time diversity gain is achieved, hence enabling the up-
link driven performance of small terminals, simulta-
neously connecting to up to three base-stations.
Coverage requirements are usually integrated us-
ing the Jakes approach (Jakes, William C. and Cox,
Donald C., 1994). Starting from a coverage area re-
quirement which is usually high (90% to 95% is typ-
ical), a log-normal fading margin is computed, which
conditions the MAPL and the cell radius calculation,
during the initial link budget. The cell radius and site
distance is, in fact, the basis for producing a theoret-
ical site grid, where the site locations are pin-pointed
in order to commit the coverage requirements.
The aim of this paper is to present an enhanced
methodology in order to extend the Jakes curves to
scenarios where site redundancy is required, such as
the LPWA networks. This allows to compute new site
grids and to introduce the concept of assisted planning
for LPWA networks, where the most suitable candi-
dates among a site list will be automatically chosen,
avoiding the inefficient and ineffective ”trial and er-
ror” method.
The paper is organized as follows. Section 2
overviews the original Jake’s curves and the cover-
age area probability determination. In the sequence,
the extended Jakes curves are developed, consider-
ing redundancy, as simulations results are presented.
Section 3 presents a case study for urban environ-
ment where the new results are applied to single, dou-
ble and triple redundancy. Section 4 overviews the
developed radio planning simulator, developed from
scratch for this project, along with the introduction
to the assisted planning concept. Finally, conclusions
are drawn in section 5.
2 DETERMINATION OF
COVERAGE AREA
PROBABILITY
This section presents the research work around ex-
tending the Jakes area coverage probability for LPWA
networks when considering site redundancy. Firstly,
past work as in (Jakes, William C. and Cox, Don-
ald C., 1994), (Rappaport, Theodore, 2001) will be
overviewed. Secondly, the authors’ additional work
will follow.
2.1 The Jakes Approach for Computing
of the Coverage Area Probability
Due to random effects of shadowing (large-scale fad-
ing) some locations within the base-station surround-
ings will presents coverage problems, i.e., will be un-
der a certain received signal threshold. It is often use-
ful to compute how the border coverage reloads to
the amount of area covered within the border. For
a circular coverage area with radius R centred on the
base-station, let there be some desired received signal
threshold γ.
In the following, the percentage of useful service
area, i.e. the percentage of area with the received sig-
nal higher or equal to γ, U (γ), is given as a known
likelihood of coverage at the cell border.
Let d represent the radial distance from the base-
station. It can be shown that if Prob(P
r
(r) > γ) is the
probability that the random received signal power, P
r
,
at d = r exceed the threshold γ within an incremental
area dA, then U (γ) is given by,
U (γ) =
1
πR
2
Z
[Prob(P
r
(r) > γ)] dA =
1
πR
2
Z
2π
0
Z
R
0
[Prob(P
r
(r) > γ)] rdrdθ
(1)
where,
[Prob(P
r
(r) > γ)] = Q
γ −P
r
(r)
σ
!
(2)
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