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  <front>
    <journal-meta>
      <journal-title-group>
        <journal-title>October</journal-title>
      </journal-title-group>
    </journal-meta>
    <article-meta>
      <title-group>
        <article-title>Brazil⋆</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Daniele Nazaré Tavares</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>José Maria Parente de Oliveira</string-name>
          <email>parente@ita.com.br</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Brasil.</string-name>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Networks</string-name>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Geographic Information System (GIS)</string-name>
        </contrib>
        <contrib contrib-type="editor">
          <string-name>Ontology, Database, Knowledge Graphs, Knowledge Representation, Semantic Networks, Telecommunications, Mobile</string-name>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Instituto Tecnológico de Aeronáutica (ITA), Praça Marechal Eduardo Gomes</institution>
          ,
          <addr-line>50. Vila das Acácias, 12228-900. São José dos Campos/SP -</addr-line>
        </aff>
      </contrib-group>
      <pub-date>
        <year>2025</year>
      </pub-date>
      <volume>02</volume>
      <issue>2025</issue>
      <fpage>167</fpage>
      <lpage>173</lpage>
      <abstract>
        <p>The information age and digital communication have transformed the way we collect, process, store, and display data. However, when dealing with georeferenced information, the challenge remains of representing spatial data in a manner consistent with its logical and semantic context. Conventional spatial tables describe attributes in isolation, failing to capture their meaning within the context in which they are embedded. This work proposes the use of knowledge graphs to integrate spatial and non-spatial databases, aiming to represent semantic relationships between geographic entities and telecommunications infrastructure across Brazil. Open data from Anatel and IBGE were used to structure the knowledge graph, which allows for the analysis of the distribution of radio base stations in each Brazilian municipality and their geoeconomic impact. The study demonstrates the feasibility of enriching analyses of mobile telecommunications infrastructure (2G, 3G, 4G, and 5G), supporting Anatel's decision-making in public policies aimed at ensuring interoperability.</p>
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. Introduction</title>
      <p>Mobile telecommunications network data is characterized by heterogeneous data types and complex
relationships between the entities represented. However, the way in which data is currently available is
limited in relation to these aspects. For this reason, a form of storage is needed that enables more eficient
and meaningful organization of this data. Knowledge graphs are emerging as a promising alternative for
organizing information on telecommunications infrastructure and services in Brazil.</p>
      <p>In this paper, we present a proposal for a knowledge graph structure that represents the topology or
architecture of mobile telecommunications networks in Brazil. The proposal allows for data scalability and
more accurate analyses of the organization and behavior of radio base stations (ERBs) in diferent regions.
The proposal also ofers the following advantages:
• Knowledge graphs allow visualization of the network topology, understanding the relationship
between its physical and logical components.
• With graph-based reasoning, it is possible to identify the root cause of failures or service degradation,
streamlining the maintenance and restoration process of the telecommunication network.
• They allow the use of performance metrics related to network configurations to recommend antenna
installation optimization strategies.</p>
      <p>
        The geospatial database was obtained from open data from the IBGE (Brazilian Institute of Geography
and Statistics), including names of states and municipalities, territorial geometries and other geospatial
information about Brazil [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ][
        <xref ref-type="bibr" rid="ref2">2</xref>
        ]. The data related to mobile telecommunications network infrastructure
was extracted from the MOSAICO ou System Integrated Spectrum Management and Control System
(Broadcasting Modules), made available by ANATEL (National Telecommunications Agency) [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ].
Proceedings of the 18th Seminar on Ontology Research in Brazil (ONTOBRAS 2025) and 9th Doctoral and Masters Consortium on
https://danynazaretech.github.io/danynazare (D. N. Tavares)
      </p>
      <p>CEUR
Workshop
Proceedings</p>
      <p>ceur-ws.org</p>
      <p>ISSN1613-0073</p>
      <p>
        The rest of the document is organized as follows: Section 2 presents related work in telecommunications
that uses knowledge graphs and ontologies; Section 3 describes the proposal for a knowledge graph for
mobile telecommunications networks in Brazil; Section 4 presents examples of queries made to the graph
and discusses its benefits; finally, Section 5 presents conclusions and suggestions for future work.
2. State of the Art
knowledge graphs began to be used in 2012 by Google [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ] for the purpose of organizing data in the
search for information at the conceptual level as a result of the interconnection of various types of data
associated by semantic relationships. Knowledge graphs, which are data structures in graphs that combine
data, relationships, and metadata to create a comprehensive understanding of the contextual object being
represented, enable knowledge extraction [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ][
        <xref ref-type="bibr" rid="ref6">6</xref>
        ]. This formal model is composed of nodes, which represent
entities or objects, while the edges indicate the inference relationships established between them.
      </p>
      <p>A notable example of this approach can be seen in Google’s search engine. When you search for the
name of a city, it not only displays related hyperlinks, but also presents organized information about its
location, cultural aspects, health infrastructure, and geographic data. This data comes from an ontologically
structured knowledge graph, which links diferent sources of information based on formally established
semantic relationships.</p>
      <p>In addition to applications in search engines, knowledge graphs have become fundamental tools in areas
such as natural language processing, recommendation systems, semantic relation extraction, knowledge
engineering, and intelligent chatbots. Their structure facilitates data organization during the preprocessing
and modeling stages, making them especially useful for feeding artificial intelligence algorithms with
contextualized and semantically enriched data.</p>
      <p>
        The paper Ontology for IP Telephony Networks [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ] presents an ontology in the field of IP telephony
networks, focusing on the development of programs for this modalidality of network. The proposal is
based mainly on the analysis of the SIP and H.323 protocols and the dominant signaling protocols in VoIP
telephony. The telephony network structure is modeled with classes representing diferent types of nodes
in the network: end-user terminals and network infrastructure. The goal is to standardize the telephony
network structure and client usage to facilitate the development of telephony applications with interoperable
data.
      </p>
      <p>
        The TOUCA Project proposes the ToCo (Telecommunication CANvas Ontology) ontology [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ], developed
to represent hybrid telecommunications networks that combine wired and wireless technologies, various
types of devices, interfaces, links, users, services, and channel quality in a modular and reusable way, based
on the Device-Interface-Link (DIL) design pattern. ToCo allows for a semantic and integrated description
of the infrastructure and behavior of modern networks, supporting applications such as software-defined
networks (SDN), performance monitoring, and interoperability between technologies.
      </p>
      <p>
        Advances in the use of knowledge graphs have also been made in the direction of eficiently compressing
the density of data generated by 6G mobile networks, called pervasive multilevel native AI (PML)[
        <xref ref-type="bibr" rid="ref9">9</xref>
        ]. In
this work, wireless data graphs are used to ”organize and condense complex and disordered data, extracting a
concise subset that represents the most efective and critical factors for network AI models that process large
volumes of wireless data”, contributing to the economy of memory in the storage of the data collected.
      </p>
      <p>In the works presented above, it is worth highlighting the relationship between telecommunications
networks and knowledge graphs to understand the semantic behavior between the physical and logical
elements of a network for the construction of new protocols, architectural elements, topologies, and data
refinement. In continental countries like Brazil, Russia, and China, where deployment costs are a barrier to
its growth, this view of the network helps to build mobile telecommunications networks eficiently.</p>
    </sec>
    <sec id="sec-2">
      <title>3. Knowledge graph of mobile telecommunications networks</title>
      <p>
        Structuring spatial data together with non-spatial data is an inherently complex task, reflecting the wide
diversity of formats, such as satellite images, cartography, vector data, matrix data, demographic data,
textual data, and numerical data. Although tables help with organization, they are limited in their ability
to visualize the semantic relationships between cartographic representation, geographic attributes, and
external data from multiple sources. For this reason, geographic information systems (GIS) arose from the
need to capture, manipulate, analyze, and model geographic data and metadata to provide an integrated and
geospatial context-oriented view [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ].
      </p>
      <p>An additional limitation of the conventional tabular model lies in the dificulty of performing complex
data queries, thereby reducing the potential to explore semantic relationships between data elements.</p>
      <p>To represent the structure of mobile telecommunications networks in Brazil using a knowledge graph, the
ifrst step was to define the types of data to be used. Cartographic data in Shapefile format, numerical data,
and text extracted from IBGE sources and georeferenced telecommunications data from Anatel’s MOSAICO
system were therefore used. Geographic, cartographic, and geoeconomic data from IBGE on Brazilian
territory were used to analyze the structure of radio base stations (ERBs) with ANATEL data, interpreting
how MOSAICO system mobile services are impacted throughout Brazilian territory.</p>
      <p>Based on the understanding of this data, the corresponding knowledge graph was generated, linking the
georeferenced data with the geographic data from the two databases. It expresses the relationships between
the data of each ERB in relation to the spectrums it controls, its influence in the regional zone, antenna
coverage by region, frequencies available for use, types of mobile services, and how each region manages
each mobile telecommunications service, all with the organization of the geographic entities described in
the IBGE data. Thus, as a basis for constructing the graph, the defined conceptual schemes of ANATEL and
IBGE data show how the ERBs are distributed and their impact on each region.</p>
      <sec id="sec-2-1">
        <title>3.1. Data description of Anatel and IBGE</title>
        <p>
          The geospatial data extracted from the IBGE platform are in Shapefile (.shp) format, which contains the
geometric characteristics and territorial boundaries of each Brazilian municipality. From the cartographic
database, 5,572 municipalities and 27 states were extracted, along with six attributes for each municipality
that are implicit in the map. External geographic information on states and municipalities was obtained
from the Cidades@ portal [
          <xref ref-type="bibr" rid="ref1">1</xref>
          ], which describes the socioeconomic and structural characteristics of each
locality, totaling 22,558 additional data points.
        </p>
        <p>The SPECTRUM MOSAICO platform from Anatel is intended to manage telecommunications services,
keep track of broadcasting station records, and show whether each ERB’s infrastructure conforms with
Anatel regulations. The open data used on licensed telecommunications stations in Brazil is in tabular .csv
format with 2,083,046 rows and 41 columns, which separates the characteristics of each station’s antennas.
This study considers mobile service stations (2G, 3G, 4G, and 5G), and through their geographic position
(latitude and longitude), it is possible to infer the impact of each ERB in the region where it is installed and
how they interact with each other.</p>
        <p>
          Using data from IBGE and Anatel, it is possible to establish spatial relationships with mobile architecture
and its relationship with stations, making it possible to infer which antennas are in a specific area, perform
network coverage or saturated area analysis, plan the network, and detect anomalies. In addition, it
is possible to integrate data from other sources to infer the operational, administrative, or regulatory
characteristics of public services. The principle behind this vision is the importance of semantic enrichment
of data from multiple domains [
          <xref ref-type="bibr" rid="ref10">10</xref>
          ], so that end users can understand the impact of the mobile network
across Brazil and consume it abruptly. .
        </p>
      </sec>
      <sec id="sec-2-2">
        <title>3.2. Conceptual data diagram</title>
        <p>A radio base station (ERB) is a fixed installation that houses the equipment responsible for enabling
communication between mobile devices and the telephone company, providing signal coverage in a geographical
area.</p>
        <p>
          Based on current legislation [
          <xref ref-type="bibr" rid="ref11">11</xref>
          ] [
          <xref ref-type="bibr" rid="ref12">12</xref>
          ] [
          <xref ref-type="bibr" rid="ref13">13</xref>
          ], each ERB is defined in the graph as an entity according to
the technical and regulatory criteria established by the MOSAICO system data. In the graph, each ERB
is configured as a component responsible for the operational management of Antennas, presenting a 1:N
cardinality relationship. Each Antenna is composed of physical attributes related to its operation, using
wireless communication technologies such as 2G, 3G, 4G, and 5G. In addition, each one has concrete physical
infrastructure and uses transmitting equipment to emit signals within the coverage area. Antennas installed
in critical locations must be identified in order to follow an installation and operation protocol that is
diferent from the others. Figure 1 shows the conceptual and topological model of the ERB structure with
the antennas and technologies that operate, the technical characteristics under their operation, associated
with the equipment used in the transmission infrastructure.
        </p>
        <p>So each antenna has a concrete physical infrastructure and uses transmitter equipment to broadcast
signals within the coverage area. Antennas installed in critical locations must be identified in order to
follow an installation and operation protocol that is diferent from the others. The Figure 1 presents the
conceptual model of the ERB structure with the antennas and the technical characteristics of their operation
associated with the equipment used in the transmission infrastructure.</p>
        <p>To model the information related to licensed ERB concessions, latitude and longitude coordinates were
used as a basis for establishing an indirect relationship between stations. This approach prevents data
explosion if the ERBs were directly connected to other stations. With the support of thematic
cartography extracted from the IBGE map, it is possible to indirectly associate each station with its structural
characteristics and infer its area of influence in the geographical region where the ERB provides signal
coverage.</p>
        <p>Thus, to represent the distribution of ERBs in cities and organize them administratively in accordance
with Anatel, only neighbouring cities in the same state were connected directly, and the state module was
connected to the capital city, as illustrated in Figure 2. This connection between cities is useful for solving
the travelling salesman problem when Anatel’s regional superintendence needs to perform maintenance and
inspections of its internal state mobile infrastructure. The states were connected directly to their neighbours
to formalize the connections between states, according to IBGE data.</p>
        <p>
          By way of illustration, Figure 3 shows the relationship between spatial data from ERBs. It helps illustrate
the argument that integrating data from the nearest stations with their geographic position contributes
to the study of improving the architecture of mobile telecommunications networks for the provision of
services in the coverage area, with the geographic and geodetic conditions presented in the IBGE data [
          <xref ref-type="bibr" rid="ref14">14</xref>
          ].
Figure 3 (a) shows the geometric distance relationship between ERBs in Rio Branco, capital of Acre, and
Figure 3 (b) shows the cartographic relationship between ERBs. Therefore, it is possible to visualize the
concentration of ERBs in the east of the capital due to a large part of its area being covered by the Amazon
Rainforest.
        </p>
      </sec>
      <sec id="sec-2-3">
        <title>3.3. Graph of knowledge</title>
        <p>Based on the conceptual models presented, a large graph was constructed representing the MOSAICO
system ERB data and IBGE data using Neo4J’s CYPHER language. The Figure 4 shows part of the graph
referring to the structure of ERB 64300. This figure shows the main mobile technologies: GSM (2G), WCDMA
(3G), LTE (4G), and NR (5G); the antennas associated with them; equipment that operates their respective
antennas; and which antennas are installed in a new project without legacy infrastructure (Greenfield). By
looking at the graph, it is possible to understand the structure of how the ERB operates, how its antennas
are connected, and how the spectrum of one antenna afects that of another, knowing at what power it
operates.</p>
        <p>Given its size and scope of representation, viewing the graph in its entirety is not very informative. For
this reason, navigation through the graph is done through specific queries written in the CYPHER language.</p>
      </sec>
    </sec>
    <sec id="sec-3">
      <title>4. Examples of the queries</title>
      <p>In order to evaluate the cohesion of the graph and its possible everyday applications, several queries were
performed, such as:
• physical and topological structure of ERB 64300 with the number of antennas and their technologies;
• antennas with diferent physical infrastructure, including the identification number of each antenna
and its classification according to the type of sharing;
• Identification of nearby stations and the operators that run them;
• distribution of mobile telecommunications infrastructure by city, state, or region.</p>
      <p>The queries performed showed how a knowledge graph can be used to model data and extract structured
information, both visually (through graphs) and in JSON and GeoJSON formats. More significantly, the
queries highlighted how the semantics of the geographic relationships between ERBs can contribute to the
extraction of information about physical and logical connections between infrastructure elements.</p>
    </sec>
    <sec id="sec-4">
      <title>5. Conclusion</title>
      <p>The challenge of representing spatial data in a manner consistent with its logical and semantic context
remains relevant, especially when dealing with georeferenced information. Traditional approaches based
on spatial tables often fail to capture the semantic relationships between attributes, limiting the integrated
analysis of geographic entities and their interactions.</p>
      <p>This work proposed an alternative based on knowledge graphs to integrate spatial and non-spatial
databases. Using open data from Anatel and IBGE, it was possible to structure a model that not only
represents the distribution of radio base stations in Brazil but also allows for richer analyses of their
geoeconomic impact and the interoperability of telecommunications networks (2G, 3G, 4G, and 5G).</p>
      <p>The results show that this approach can significantly contribute to public policy decision-making, helping
Anatel identify areas requiring infrastructure investments or regulatory adjustments to ensure eficiency
and equity in access to telecommunications services.The Future work could explore applying this model in
other geographical contexts or sectors, expanding its usefulness for urban and regional planning.</p>
    </sec>
    <sec id="sec-5">
      <title>Declaration on Generative AI</title>
      <p>During the preparation of this work, the author(s) used GPT-4, Language Tools and Grammarly in order to:
Grammar, spelling and plagiarism check. After using these tool(s)/service(s), the author(s) reviewed and
edited the content as needed and take(s) full responsibility for the publication’s content.</p>
    </sec>
  </body>
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