Network Coverage Mapping

Irish Interdisciplinary Journal of Science & Research (IIJSR)
Vol.6, Iss.2, Pages 110-122, April-June 2022
ISSN: 2582-3981 www.iijsr.com
110
Network Coverage Mapping
Pradeepa G1
, Sudha R.V.2
, Dhivya Dharshini N3
, Niroja K4
& Sri Praba S5
1-2
Assistant Professor, Department of Information Technology, Vivekanandha College of Technology for Women.
3-5
Student, Department of Information Technology, Vivekanandha College of Technology for Women.
DOI: http://doi.org/10.46759/IIJSR.2022.6215
Copyright © 2022 Pradeepa G et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which
permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Article Received: 20 March 2022 Article Accepted: 25 May 2022 Article Published: 17 June 2022
1. Introduction
Along with voice, data communication has become an integral part of consumer needs. Peoples on the move
with smartphones demand high-speed data service. Apart from these, consumer satisfaction with a greater
quality of service also needs to be maintained. All of these brought attention to the scarce resource upon
which the technology depends - The frequency Spectrum.
The evolution of the technology from the 1st to the 4th generation networks has all been based upon the more
and more efficient use of the frequency spectrum over the capacity and throughput offered. First, the wireline
data networks improved and higher data rates were possible. Wireless technologies provide ubiquitous access
to mobile users, enabling consumers with a broad range of mobility and a variety of wireless multimedia
services and applications.
Wireless access technologies provide data access through wireless media to consumer and business markets.
The most common example of wireless access is a wireless local area network. Wireless access is also an
attractive option to network operators in geographically remote areas with no or limited wired network.
Citizens today aspire more and more to be informed, entertained, shop, transfer money and communicate
using their mobile phones. Starting a conversation at home and continuing it over their car's speakers, sending
out a request while traveling, and using that information once they arrive at their destination. Finishing up
some work or getting a head-start while on public transport. Getting groceries or shopping online, paying for
a taxi, or receiving their salary using mobile payment solutions. All actions that are now possible on mobile
networks, coming to complement fixed networks.
In reality, however, a distinction must be made between those areas where networks enable access to all of the
activities listed above, and those where only some of these activities are possible – not to mention the white
ABSTRACT
Mobile signal strength (coverage) maps are of great importance to cellular operators for network planning and operation are expensive to
obtain, imperfectly reflective of call quality outcomes, and potentially constructed from biased samples. Users of smartphones utilize
high-speed network services while commuting on public transit and hope to have a consistent, high-quality connection. Measuring and
monitoring coverage and quality of service mean being able to assess reality and its representation. Data collection is a vital ingredient in this
process. Finding Mobile signal strength and Mapping the Coverage areas using GIS through differentiating the Network. Due to the massive
load demand on cellular networks and frequent changes in the underlying radio channel, users often experience sudden unexpected variations
in the connection quality. To overcome variations, we create a Map to differentiate the signal strength with a regular update through the
Received Signal Strength Indicator (RSSI) in QGIS Software using Python and XML plugins.
Index Terms: QGIS, Biased samples, Massive load.

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areas where the absence of network coverage makes it impossible to use one‟s device for any form of
communication whatsoever. Network Coverage mapping is a process used to discover and visualize physical
and virtual network connectivity via a group of interrelated tasks that facilitate the creation of a network map.
2. Measuring Mobile Network Performance
Measuring coverage means verifying whether a user can connect to their mobile network, establish and
maintain a call for a set minimum period, achieve a specific data transmission speed, and access different
services. Several parameters can be used to measure this coverage. If signal strength (signal range and quality)
provides an initial indication, measuring service accessibility (ringtone within a certain time, time it takes to
download several bytes of data, etc.) makes it possible to obtain a more accurate representation of coverage.
By combining these different types of measurement we can eliminate, to some degree, disparities between
operators' stated coverage and users' experience. Providing only information on signal range can, on the
contrary, result in a situation where users are unable to access services despite a location being covered in
theory. Quality of service can be measured using several criteria or indicators set by the regulator. These
indicators or criteria make it possible to measure voice call performance (accessibility, integrity, continuity)
compared to benchmark thresholds. Indicators for measuring mobile internet quality are more challenging to
determine, given the heterogeneousness of data services.
The received signal strength indicator (RSSI) indicated the energy loss in the process of signal transmission;
the RSSI value is associated with the size of signal attenuation. In the process of signal transmission, the
smaller the RSSI value the less the attenuation. Usually, the RSSI ranking is based on the experience model or
theory model. The RSSI ranging of model-based experience has shown that an offline database is built
between a few RSSI values of nodes which are known location information and their distance of signal
propagation; in the process of nodes location, the stored data in the database is constantly compared to
implement nodes location.
The RSSI ranging model-based theory implemented nodes localization by determining the environmental
parameters in the loss model of signal propagation and plugging the RSSI value which is received from
receiving nodes into the model, to estimate the distance between nodes. There is a key to the former method;
lots of measuring work off-line in the region is required; in addition, the location accuracy is limited by the
number of nodes and measuring workload. The core of the latter method lies in researching critical parameters
of the model detail by the accurate measuring of RSSI value; hardware conditions and actual environment can
be better reflected; in addition, location accuracy and improved location performance can be enhanced.
Common methods of RSSI ranging are as follows, which are based on the theory model: the path loss model
of free space propagation and the block model of logarithmic normal (Shadowing model), and so forth.
The path loss model of free space propagation is an ideal transmission case, it is known that there is an infinite
vacuum around the antenna, the signal transmission energy is only related to the transmission distance, and
there is a linear relationship between the signal transmission energy and transmission distance, this model
does not affect obstacles and scattered reflection, and so forth. The path loss model is as follows:

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Loss=32.44+10nlog⁡(d)+10nlog(f) (1)
In this formula, loss indicated the path loss of signal energy, d indicated the signal transmission distance
(m), f indicated the wireless signal frequency (MHz), and n indicated the path attenuation factor in the actual
environment. However, the application environment of the wireless sensor signal is not in free space, but in
the actual environment such as industrial sites or indoor buildings; it needs to consider shade and absorbance
by obstacles and the interference of scattered reflection, and so forth.
The attenuation characteristic of channels in the long-distance is following the lognormal distribution; it is
commonly used by the block model of logarithmic normal; the path loss model is as follows:
PL(d)=PL(d0)+10nlog⁡(dd0)+Xσ (2)
In this formula, PL(d) indicated the path loss of receiving sign when the measuring distance is d (m), it
indicated the absolute power value, and it is in dBm; PL(d0) indicated the path loss of receiving sign when the
reference distance is d0; n indicated the path loss index in a specific environment; it indicated the speed of the
path loss, which is increased along with increasing distance; Xσ is in dB; it is a cover factor when the range of
standard deviation σ is 4~10 and the mean value is 0; the larger the σ, the greater the uncertainty of the model.
The signal strength of receiving nodes is as follows:
RSSI=Pt-PL(d) (3)
In this formula, Pt indicated the signal transmission power, PL(d) indicated the path loss when the distance
is d, and they are both in dBm. A indicated the signal strength which is received from reference nodes at the
distance d0; A is as follows:
A=Pt-PL(d) (4)
The path loss model is as follows, which is measured at the real distance d (m):
P(d)=P(d0)-10nlog(dd0)-Xσ (5)
In this formula, P(d) indicated the received signal strength when the measured real distance
is d (m). P(d0) indicated received signal strength when the reference distance is d0, Xσ~N(0,σ2).
We take the reference distance d0=1 m; it can be obtained from formula (3) and formula (5).
RSSI=A-10nlog(dd0)-Xσ (6)
is regarded as the RSSI value of multiple times of measurement
= -10nlog(d) (7)
d is regarded as the undetermined distance
d=10(A-RSSI)/10n (8)

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2.1. Acquisition of RSSI Data
Signal strength indicator (RSSI) is read from the register RSSI_VAI in the data packets which are received
from sensor receiving nodes, a sensor node is set and regarded as a receiving device at intervals of 1 m, and
RSSI data is measured at more than 400 times at every place, and each sensor node is received and recorded
its signal strength value. eceiving nodes only can receive a few signal strength values beyond 25 m; parts of
signal value are not detected, because the RSSI value of characterization signal attenuation is included in data
packets, so it is meaningless to keep measuring. In this paper, the range of I ranging is kept at 0~25 m. For
example, the distance between sending node and receiving node is taken 5 m and 10 m, respectively, we have
made statistics for collecting RSSI value and chosen more than 400 times of measurement to be a sample,
although RSSI generally presented obvious non-stationary characteristics, the RSSI value in the certain
distance is always fluctuated up and down between the constant real RSSI value, the closer distance from
emission node, and the frequenter change of measurement value; on the contrary, the farther the distance from
emission node, the gentler the change.
2.2. Shadowing Model
To exactly describe the actual measurement environment and ensure the accuracy of RSSI ranging, the
parameters of the signal propagation model are needed to define. A indicated the received signal strength
value when the reference distance is d0=1 m and n indicated the path loss index. The determination of
parameter A is as follows. A=P(d0), the radio frequency parameter A indicates the received absolute value of
mean energy, which is received from the projection node when the distance is 1 m; it is in dBm. When the
distance is 1 m, 500 groups of data are continuously measured; finally, there is a result that A=117.
The determination of parameter n is as follows. Environment factor n indicated, along with the increasing
distance, the speed of signal loss in the process of the actual transmission. They are satisfied with the
following relationship:
n= - 10*log(d) (9)
Where, n is obtained by generating more than 3000 groups of data in the range of 2~10 m.
3. GIS Description
GIS open source software has been growing, and the development and sharing of open source applications in
environmental areas have significant benefits, namely the free distribution and the public availability of the
code, allowing user customization. The Free and Open Source Software (FOSS) for GIS applications has
several advantages, as new applications can be developed under them using open-source programming
languages, such as Python, and different libraries (for instance, QGIS software, QGIS Application
Programming Interface (API) and Qt API are commonly used in the development of new applications).
Several GIS applications have been developed in different contexts, such as internet cafes, Telecom, Mobile
Frequency, and others, combining different methodologies, making effective and improving the performance
of the computing procedures. This trend was also, allowing the automatization of technologies and procedures

114
into agriculture practice. GIS software tools have been used in several studies to create the spatial variables
required to predict agriculture production. The QGIS software is shown in fig.1.
Fig.1.
4. Tools in QGIS
4.1. Vector Data
4.1.1. Point features
The first thing we need to realize when talking about point features is that what we describe as a point in GIS
is a matter of opinion, and often dependent on scale. Let's look at cities for example. If we have a small-scale
map, it may make sense to represent a city using a point feature. However, as we zoom in to the map, moving
towards a larger scale, it makes more sense to show the city limits as a polygon.
4.1.2. Polyline features
Where a point feature is a single vertex, a polyline has two or more vertices. When two vertices are joined, a
line is created. When more than two are joined, they form a „line of lines‟, or polyline. A polyline is used to
show the geometry of linear features such as roads, rivers, contours, footpaths, flight paths, and so on.
Sometimes we have special rules for polylines in addition to their basic geometry. For example contour lines
may touch (e.g. at a cliff face) but should never cross over each other. Similarly, polylines used to store a road
network should be connected at intersections. In some GIS applications, we can set these special rules for a
feature type and the GIS will ensure that these polylines always comply with these rules.
4.1.3. Polygon features
Polygon features are enclosed areas like the internet, Internet cafes, Telecom boundaries, and so on. Like
polyline features, polygons are created from a series of vertices that are connected with a continuous line.
However, because a polygon always describes an enclosed area, the first and last vertices should always be at
the same place! Polygons often have shared geometry - boundaries that are in common with a neighboring

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polygon. Many GIS applications can ensure that the boundaries of neighboring polygons exactly coincide.As
with points and polylines, polygons have attributes. The attributes describe each polygon. For example, a dam
may have attributes for depth and water quality.
4.1.4. Vector data in layers
Most GIS applications group vector features into layers. Features in a layer have the same geometry type (e.g.
they will all be points) and the same kinds of attributes (e.g. information about what species a tree is for a
tree's layer) as shown in Fig.2. For example, if we have recorded the positions of all the footpaths in a school,
we will usually be stored together on the computer hard disk and shown in the GIS as a single layer. This is
convenient because it allows us to hide or show all of the features for that layer in our GIS application with a
single mouse click.
Fig.2.
4.1.5. Editing vector data
The GIS application will allow us to create and modify the geometry data in a layering process called
digitizing. If a layer contains polygons (e.g. network, internet cafe), the GIS application will only allow us to
create new polygons in that layer. Similarly, if we want to change the shape of a feature, the application will
only allow us to do it if the changed shape is correct. For example, it won't allow us to edit a line in such a way
that it has only one vertex. Creating and editing vector data is an important function of a GIS since it is one of
the main ways in which we can create personal data for things we are interested in. As well as creating our
data, there is a lot of free vector data that we can obtain and use.
4.1.6. Scale and vector data
Map scale is an important issue to consider when working with vector data in a GIS. When data is captured, it
is usually digitized from existing maps, or by taking information from surveyor records and global positioning
system devices. Maps have different scales, so if we import vector data from a map into a GIS environment,
the digital vector data will have the same scale issues as the original map. Many issues can arise from making
a poor choice of map scale.

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4.1.7. Symbology
When we add vector layers to the map view in a GIS application, they will be drawn with random colors and
basic symbols. One of the great advantages of using a GIS is that we can create personalized maps very easily.
The GIS program will let us choose colors to suit the feature type. The GIS will also let us adjust the symbol
used. So if we have a tree point layer, we can show each tree position with a small picture of a tree, rather than
the basic circle marker that the GIS uses when we first load the layer. Symbology is a powerful feature,
making maps come to life and the data in our GIS easier to understand.
4.2. Vector Attribute Data
Features are real-world things such as roads, property boundaries, electrical substation sites, and so on. A
feature has a geometry that determines if it is a point, polyline, or polygon and attributes which describe the
feature.
4.2.1. Attributes
Attributes for a vector feature are stored in a table. A table is like a spreadsheet. Each column in the table is
called a field. The records in the attribute table in a GIS each correspond to one feature. Usually, the
information in the attribute table is stored in some kind of database. The GIS application links the attribute
records with the feature geometry so that we can find records in the table by selecting features on the map, and
find features on the map by selecting features in the table. Each field in the attribute table contains a specific
type of data such as text, numeric, or date as shown in Fig.3. Deciding what attributes to use for a feature
requires some thought and planning.
Fig.3.
4.2.2. Single Symbols
If a feature is symbolized without using any attribute table data, it can only be drawn simply as shown in
Fig.4. A GIS application will normally allow us to set the symbology of a layer using a dialog box.In this
dialog box, we can choose colors and symbol styles depending on the geometry type of a layer.

117
Fig.4.
4.2.3. Graduated Symbols
Sometimes vector features represent things with a changing numerical value. Setting colors based on discrete
groups of attribute values is called Graduated Symbology in QGIS. Graduated symbols are most useful when
we want to show clear differences between features with attribute values in different value ranges. The GIS
Application will analyze the attribute data (e.g. height) and, based on the number of classes we request, create
groupings for us.
4.2.4. Continuous Color Symbols
Sometimes it is useful to draw features in a color range from one color to another. The GIS Application will
use a numerical attribute value from a feature to decide which color to use. Continuous: Continuous color
symbology uses a start color and an end color and creates a series of shades between those colors. After
defining the minimum and maximum colors in the color orange, the color features drawn in will depend on
where the attribute lies in the range between minimum and maximum.
4.2.5. Unique Value Symbols
Sometimes the attributes of features are not numeric, but instead, strings are used. 'String' is a computer term
meaning a group of letters, numbers, and other writing symbols. Strings attributes are often used to classify
things by name.
Fig.5.
We can tell the GIS Application to give each unique string or number its color and symbol. Road features may
have different classes and each is drawn in the map view of the GIS with different colors or symbols. Within

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the GIS Application, we can open/choose to use Unique Value symbology for a layer. The GIS will scan
through all the different string values in The attribute field and build a list of unique strings or numbers. Each
unique value can then be assigned a color and style as in Fig.5
4.3. Data Capture
There are two key concepts to vector data, namely: geometry and attributes. The geometry of a vector feature
describes its shape and position, while the attributes of a vector feature describe its properties such as color,
size, age, etc, Word processors, spreadsheets, and graphics packages are all programs that let us create and
edit digital data. Each type of application saves its data into a particular file format. For example, a graphics
program will let us save our drawing as a .jpg JPEG image, word processors let us save our document as a
.odtOpenDocument or .doc Word Document, and so on. Just like these other applications, GIS Applications
can store their data in files on the computer's hard disk. There are several different file formats for GIS data,
but the most common one is probably the 'shape file'. The name is a little odd in that although we call it a
shape file (singular), it consists of at least three different files that work together to store our digital vector
data, as shown in the table1.
Table 1
Extension Description
.shp The geometry of vector features is
stored in this file.
.dbf The attributes of vector features
are stored in this file.
.shx This file is an index that helps the
GIS Application to find features
more quickly.
Many GIS applications are also able to store digital data inside a database. In general, storing GIS data in a
database is a good solution because the database can store large amounts of data efficiently and can provide
data to the GIS Application quickly. Using a database also allows many people to work with the same vector
data layers at the same time.
4.3.1. Creating an empty shapefile
Once we have planned what features we want to capture into the GIS, and the geometry type and attributes
that each feature should have, we can move on to the next step of creating an empty shapefile. The process
usually starts with choosing the 'new vector layer' option in our GIS Application and then selecting a
geometry type which means choosing either point, polyline, or polygon for the geometry. Next, we will add
fields to the attribute table. Normally we give short field names, have no spaces, and indicate what type of
information is being stored in that field. Example field names may be 'pH', ' oofColor‟, „network frequency',

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and so on. As well as choosing a name for each field, we need to indicate how the information should be
stored in that field. The shapefile format allows us to store the numeric field information as either a whole
number (integer) or a decimal number (floating point) The final step for creating a shapefile is to give it a
name and a place on the computer hard disk where it should be created which is shown in Fig.6.
Fig.6.
4.3.2. Adding data to shapefile
We need to enable editing in the shapefile using the 'enable editing' menu option or toolbar icon in the GIS
Application. Shapefiles are not enabled for editing by default to prevent accidentally changing or deleting the
data they contain.
Next, we need to start adding data. There are two steps we need to complete for each record we add to the
shapefile:
 Capturing geometry.
 Entering attributes.
The process of capturing geometry is different for points, polylines, and polygons. To capture a point, we first
use the map pan and zoom tools to get to the correct geographical area where we are going to be recording
data. Next, we will need to enable the point capture tool. Having done that, the next place we click with the
left mouse button in the map view is where we want our new point geometry to appear. After we click on the
map, a window will appear and we can enter all of the attribute data for that point. If we are unsure of the data
for a given field we can usually leave it blank, but be aware that if we leave a lot of fields blank it will be hard
to make a useful map from our data.
To capture a polyline the process is similar to that of a point, in that we need to first use the pan and zoom
tools to move the map in the map view to the correct geographical area. We should be zoomed in enough so
that our new vector polyline feature will have an appropriate scale. When we are ready, we can click the
polyline capture icon in the toolbar and then start drawing our line by clicking on the map. After we make our
first click, we will notice that the line stretches like an elastic band to follow the mouse cursor around as we
move it. Each time we click the left mouse button, a new vertex will be added to the map. When we have
finished defining our line, use the right mouse button to tell the GIS Application that we have completed our

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edits. As with the procedure for capturing a point feature, we will then be asked to enter the attribute data for
our new polyline feature. The process for capturing a polygon is almost the same as capturing a polyline
except that we need to use the polygon capture tool in the toolbar.
4.4. Map Production
Map production is the process of arranging map elements on a sheet of paper in a way that, even without many
words, the average person can understand what it is all about. Maps are usually produced for presentations
and reports where the audience or reader is a politician, citizen, or learner with no professional background in
GIS. Because of this, a map has to be effective in communicating spatial information. Common elements of a
map are the title, map body, legend, north arrow, scale bar, acknowledgment, and map border which are
shown in Fig.7.
Fig.7.
4.4.1. Map title
The map title is very important because it is usually the first thing a reader will look at on a map. It can be
compared with a title in a newspaper. It should be short but give the reader a first idea of what the map is
about.
4.4.2. Map Border
The map border is a line that defines exactly the edges of the area shown on the map. When printing a map
with a graticule (which we describe further down), we often find the coordinate information of the graticule
lines along the border lines.
4.4.3. Map Legend
A map is a simplified representation of the real world and map symbols are used to represent real objects.
Without symbols, we wouldn‟t understand maps. To ensure that a person can correctly read a map, a map
legend is used to provide a key to all the symbols used on the map. It is like a dictionary that allows us to

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understand the meaning of what the map shows. A map legend is usually shown as a little box in a corner of
the map. It contains icons, each of which will represent a type of feature.
4.4.4. Scale
The scale of a map, is the value of a single unit of distance on the map, representing the distance in the real
world. The values are shown in map units such as meters, feet, or degrees. The scale can be expressed in
several ways, for example, in words, as a ratio, or as a graphical scale bar. Expressing a scale in words is a
commonly used method and has the advantage of being easily understood by most map users. Another option
is the representative fraction (RF) method, where both the map distance and the ground distance in the real
world are given in the same map units, as a ratio. A scale expression as a graphic or bar scale is another basic
method of expressing a scale. A bar scale shows measured distances on the map.
5. Conclusion
This paper presented the QGIS applicability in Network monitoring, with the advanced methods of data
analysis. The developed solution implements all the requirements we proposed for that purpose and
successfully achieves our objectives. The presented paper demonstrated how satellite images can be
processed and visualized the Mobile Signal Strength using RSSI Algorithm through QGIS Software. A
particular way of processing this data was also implemented, consisting of creating a signal strength grid
covering the Earth to be displayed in a coverage map. The work now serves as a basis for others to build upon
in the future. With more measurements in our database, it will be interesting to cross them over with external
data, to perform studies such as the coverage within different geographical areas, the correlation of signal
strength with the topographical information in a given area, or the location of public Wi-Fi hotspots.
Declarations
Source of Funding
This research did not receive any grant from funding agencies in the public or not-for-profit sectors.
Consent for publication
Authors declare that they consented for the publication of this research work.
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