RECyT
Year 25 / No 40 / 2023 /
DOI: https://doi.org/10.36995/j.recyt.2023.40.007
Empowering
IoT Development with LPWAN Technology: A Case Study at the National University
of Misiones
Potenciando el
Desarrollo de IoT con Tecnología LPWAN: Caso de
Estudio en la Universidad Nacional de Misiones
Eduardo O., Sosa1, *; Milton E., Sosa1
1- Faculty of Exact, Chemical and Natural Sciences.
National University of Misiones.
* E-mail: eduardo.sosa@unam.edu.ar
Received: 11/09/2023; Accepted: 20/10/2023
Abstract
This document
underscores the vital role of Low Power Wide Area Network (LPWAN) technology in
advancing the Internet of Things (IoT) and enabling connectivity for low-power
devices, prioritizing factors like range, durability, and cost-efficiency. It
explores the influences on LPWAN performance, including Ultra Narrow Band (UNB)
and Spread Spectrum (SS) modulations, offering in-depth insights into their
technical characteristics, pros, and cons across licensed and unlicensed
operational spectrums. Notable challenges encompass battery life, quality of
service, coverage, and expenditure. The city of Posadas, Argentina, is showcased
as a successful LoRaWAN testbed, illustrating the system's commendable
performance and functionality.
Keywords:
LPWAN, Internet of Things, LoRaWAN, TTN, TTNMapper.
Resumen
Este documento analiza
la importancia de las redes de área amplia y baja potencia (LPWAN) en la
expansión del Internet de las Cosas (IoT) y en la
conectividad de dispositivos de bajo consumo. Se centra en las tecnologías
LPWAN con modulaciones Ultra Narrow Band (UNB) y Spread Spectrum
(SS), evaluando sus características técnicas, ventajas y desventajas en función
de su espectro operativo, ya sea licenciado o no licenciado. Los principales
desafíos abordados son la duración de la batería, la calidad de servicio, la
cobertura y los costos. Se destaca el éxito del sistema LoRaWAN en la ciudad de
Posadas, Argentina, como un ejemplo de aplicación exitosa de estas tecnologías
en la práctica.
Palabras clave: LPWAN, Internet de las
cosas, LoRaWAN, TTN, TTNMapper.
Introduction
The
fourth industrial revolution is the era of wireless communication that enables
widespread connectivity between machines and objects. Over the years,
communication systems have evolved and are now capable of supporting an
exponentially growing number of interconnected devices. (Figure 1)
IoT applications demand
technologies that are energy-efficient, cost-effective, and, above all, of low
complexity. As a rule, their usage profiles must be carefully considered to
extend the lifespan of nodes to the maximum.
Figure 1. Prospective evolution of interconnected devices [1].
The Internet of Things (IoT)
demonstrates steady growth, forming a series of networks with different design
objectives and coverage. Some are intended solely for local area coverage,
while others offer broader coverage, interconnecting sensors, actuators, meters
(for water, gas, electricity, or parking), vehicles, appliances, and more.
IoT applications demand
technologies that are energy-efficient, cost-effective, and, above all, of low
complexity. As a rule, their usage profiles must be carefully considered to
extend the lifespan of nodes to the maximum.
If we add the inherent requirements
of IoT projects to the need for wireless communication over considerable
distances (for security, motion control, agriculture, smart measurement, smart
cities, and smart homes), the demand for specific technologies becomes even
more relevant [2]. Short-range
technologies (such as Bluetooth, Wi-Fi, 6LowPAN, industrial, scientific, and
medical radio bands - ISM -, IEEE, etc.) are not the most suitable, whereas
those based on cellular communications (3G, 4G, and 5G) can provide broader
coverage but with excessive power consumption. These fundamental requirements
in IoT have driven the adoption of Low Power Wide Area (LPWA) communication
technologies.
LPWA enables communications over
distances ranging from 10 to 40 km in rural areas and 1 to 5 km in urban areas as
highly energy-efficient and cost-effective. The radio chip can be obtained for
less than €2, and the operational cost is estimated at €1 per device per year [3], This has
driven its use in both outdoor and indoor environments [4], [5]. Therefore, the
utilization of LPWA is justified when there is a need to transmit limited
information over a distance greater than what is typically considered in other
known wireless networks
LPWAN technologies employ two main techniques in the
physical communication layer: Ultra Narrow Band (UNB) and Spread Spectrum (SS),
making the selection of the most appropriate technique paramount.
Among the trending technologies, we
can mention Sigfox UNB [7], a reliable
wireless signal for IoT devices through an intelligent and adaptable network;
LoRa (Long Range) [8] a low-power technology designed
specifically for long-range communication between IoT devices; and NB-IoT [9] (Narrowband-IoT) also known as Narrowband
Internet of Things, which is a cellular technology operating within licensed
spectrum, allowing it to leverage existing cellular infrastructure for IoT
connectivity. These three technologies exhibit significant technical differences,
as observed in Table 1.
Table 1. LPWAN Technologies Contrast.
|
|
LoRaWAN |
Sigfox UNB |
NB-IoT |
|
Frequency
band |
Open
use |
Open
use |
license |
|
Reach
(urban) |
5
Km |
10
Km |
1
Km |
|
Reach
(rural) |
20
Km |
40
Km |
10
Km |
|
Maximum
data rate |
50
Kbps |
0,1
Kbps |
200
Kbps |
|
Maximum
messages/day |
Unlimited |
140
up/4 down |
unlimited |
|
Modulation |
CSS |
BPSK |
QPSK |
|
Encryption |
Yes (AES 128b) |
No |
Yes
(LTE) |
|
Adaptive
data rate (ADR) |
Yes |
No |
No |
|
Private
Networks |
Yes |
No |
No |
|
Access
by |
Any |
Operator |
Operator |
|
Localization |
RSSI
y TDOA |
RSSI |
No |
Sigfox and LoRa both originated
from startup projects. Sigfox operates and commercializes its own IoT solution
in over 75 countries and is continually expanding by partnering with network
operators worldwide [7]. LoRa was
acquired by Semtech in 2015 [10] and its standardization has been overseen by
LoRa Alliance [8]. LoRaWAN is an
open-source protocol that runs over the LoRa physical layer, enabling a medium
access control mechanism for communication among multiple devices and network
gateways. Unlike Sigfox and NB-IoT,
LoRaWAN offers the ability to implement private
networks and easy integration with various network platforms worldwide (e.g.,
The Things Network [11]). Because of
this and its open-access specifications, LoRaWAN has attracted attention from
the research community since its inception.
NB-IoT is developed by the Third
Generation Partnership Project (3GPP) [12], and is based
on narrowband radio technology using the same frequencies as LTE (Long Term
Evolution) and QPSK (Quadrature Phase Shift Keying) modulation. To simplify it
as much as possible and thereby reduce costs and consumption, NB-IoT eliminates
many functions of LTE, including handover, channel quality monitoring, carrier
aggregation, and dual connectivity. Some authors consider NB-IoT as a new
wireless interface [13].
Technology
Sigfox deploys proprietary base stations equipped with
software-defined cognitive radios and connects them to backend servers through
an Internet Protocol (IP) network. End devices use binary phase shift
modulation (BPSK) on an ultra-narrowband ISM sub-GHz (100 Hz) carrier. ISM
bands do not require licenses, with frequencies of 868 MHz in Europe, 915 MHz
in the Americas and Oceania, and 433 MHz in Asia. By utilizing the
ultra-narrowband, Sigfox efficiently utilizes bandwidth and experiences very
low levels of noise and energy consumption [14], along with
high receiver sensitivity and a simple antenna design, transmitting at a rate
of only 100 bps. The number of messages through the uplink is limited to 140
messages per day, with a maximum length of 12 bytes. However, the number of
messages through the downlink is limited to four messages per day with a
maximum payload length of eight bytes, which does not support acknowledgment of
all uplink messages. Without proper acknowledgment support, the reliability of
uplink communication is ensured using time and frequency diversity, as well as
transmission duplication. Each end-device message is transmitted three times by
default on different frequency channels: 400 orthogonal channels of 100 Hz
(including 40 reserved and unused channels) [15]. Since base
stations can receive messages simultaneously on all channels, the end device
can randomly choose a frequency channel to transmit its messages, simplifying
the end device design and reducing its cost.
LoRa is a physical layer technology that modulates
signals in the ISM sub-GHz band using a patented spread spectrum technique. Bidirectional
communication is provided by chirp spread spectrum (CSS) modulation. The
resulting signal has low noise levels, giving it high resistance to
interference, making it difficult to detect or block [16]. LoRa uses six
spreading factors (SF7 to SF12). A higher spreading factor allows for greater
range at the expense of a lower data rate (ranging from 0.3 to 50 kbps), and
vice versa. The maximum payload length for each message is 243 bytes.
The LoRaWAN specification is a protocol designed to
wirelessly connect "things" to the Internet through regional,
national, or global networks. It focuses on key IoT requirements: bidirectional
communication, security, mobility, and localization [17]. LoRaWAN is
implemented in a star-of-stars topology, where gateways transmit messages
between end devices and a central network server. These gateways are connected
to the network server through standard IP connections and act as transparent
bridges, converting radio frequency packets from end nodes into IP packets and
vice versa. Wireless communication takes advantage of the long-range
characteristics of the LoRa physical layer, enabling a single-hop link between
the end device and one or multiple gateways. All nodes are capable of
bidirectional communication, and there is support for multicast addressing
groups to efficiently use the spectrum during tasks such as over-the-air
firmware updates (FOTA) or other mass distribution messages.
Using LoRaWAN, every message transmitted by an end
device is received by all gateways within range. LoRaWAN's
redundant reception quality improves the proportion of successfully received
messages. However, achieving this feature requires multiple gateways, which can
increase the cost of network deployment. The resulting duplicate receptions are
filtered at the backend system, which also has the intelligence to verify
security, send acknowledgments to the end device, and forward the message to
the corresponding application server. For locating end devices, it uses the
Time Difference of Arrival (TDOA) technique supported by highly accurate time synchronization
among multiple gateways [18].
NB-IoT is a narrowband IoT technology that can coexist
with the Global System for Mobile Communications (GSM) and LTE systems under
licensed frequency bands. NB-IoT occupies a frequency bandwidth of 200 KHz,
corresponding to a resource block in GSM and LTE transmissions [9]. The NB-IoT
communication protocol is based on the LTE protocol, minimizing its
functionalities and enhancing them as needed for IoT applications [19]. NB-IoT allows
connectivity for up to 105 end devices per cell, with the possibility of
expanding capacity by simply adding more NB-IoT carriers. It employs Frequency
Division Multiple Access (FDMA) in the uplink and Orthogonal Frequency Division
Multiple Access (OFDMA) in the downlink, using Quadrature Phase Shift Keying
(QPSK) modulation. The data rate is limited to 200 kbps for the downlink and 20
kbps for the uplink, with a maximum message size of 1600 bytes.
LPWAN selection for IoT, key criteria
When selecting a Low-Power Wide-Area Network (LPWAN)
technology for IoT applications, there are several key criteria to consider.
Coverage
and Range: The wide area indicates the coverage that can be
directly achieved without the need for another mesh network to extend the range
[20]. Two techniques
can be used to achieve long distances: Sub-GHz and special modulation schemes. Sub-GHz
is used by most LPWA technologies due to its reliability, robust communication,
and low power consumption [21]. Compared to
2.4 GHz, Sub-GHz experiences less frequency attenuation, less congestion, and
fewer multipath fading effects caused by obstacles and dense surfaces. Due to
its robustness and reliability, Sub-GHz enables extended communication range
and low power consumption. LoRa can provide coverage for a city, whereas NB-IoT
coverage is limited to LTE coverage areas, making NB-IoT less suitable for
suburban and rural areas where LTE coverage networks are often absent. In such
cases, LoRa and Sigfox are more appropriate options [22].
Data
Rate: Low-Power Wide-Area Network (LPWAN) technologies are
designed for applications that prioritize long-range communication and low
power consumption over high data rates. They strike a balance between energy
efficiency, long-range communication, and moderate data throughput, making them
a popular choice for connecting IoT devices in scenarios where low power
consumption is critical, and data transmission is intermittent or sporadic.
However, when high data rates or real-time communication are essential,
alternative wireless technologies may be necessary. The choice of LPWAN or
other wireless standards depends on the specific needs of the IoT application.
Power
Efficiency: LPWAN is known for its low power consumption, making
it suitable for battery-operated devices typically provide lower data rates
compared to cellular networks. The battery life of an IoT device primarily
depends on the network topology and the duty cycle. LPWAN connects devices
directly to the base station, bypassing the energy consumption associated with
packet transmission through multi-hop networks [23]. The duty cycle
of LPWA adapts to the application, power source, and traffic.
Scalability: LPWAN
scalability encompasses device, coverage, traffic, application, service
provider, interoperability, cloud, and security scalability. This scalability
enables IoT deployments to expand and adapt to changing requirements, making
LPWANs a versatile choice for a wide range of IoT applications.
Deployment
Costs: hardware, network access fees, and operational
expenses, need to be considered. It is important to conduct a thorough cost
analysis based on the specific IoT project scope, scale, and requirements. This
analysis should consider both upfront deployment costs and ongoing operational
expenses to create a comprehensive budget. Some LPWAN technologies may be more
cost-effective for specific use cases. The total cost of LoRa and Sigfox is
lower than that of NB-IoT, primarily due to the cost of spectrum (licensing).
Sigfox nodes can be produced for less than €2, LoRa nodes range from €3 to €5,
while an NB-IoT end device can cost more than €20. Regarding implementation
costs, a Sigfox base station costs around €4,000, an NB-IoT base station costs
€15,000, while a LoRa gateway costs less than €100 [24]. It is evident
that Sigfox and LoRa are more cost-effective when compared to NB-IoT.
Security: LPWAN
offers unique benefits for IoT applications, but they also come with specific
security challenges as: Limited Security Features, Device Authentication, Data
Encryption, Key Management, Device Tampering, DoS Attacks, Firmware and
Software Updates, Physical Security of Gateways, Regulatory Compliance and
Interoperability. To mitigate these security issues in LPWAN, the following
best practices need to be considered: strong authentication mechanisms for
device onboarding, end-to-end encryption, update firmware and software,
intrusion detection systems, secure physical access to gateways.
Interoperability: is crucial for hassle-free deployment. Sigfox
and LoRa have reached a certain level of maturity and are applied in various
countries, while NB-IoT lags behind in implementations. The significant
advantage of the LoRa ecosystem is its flexibility. Unlike Sigfox
and NB-IoT, LoRa offers the
implementation of local networks.
Latency:
While LPWAN offers good coverage, they may have higher latency compared to
cellular networks. For applications that are not sensitive to latency and
involve transferring a small amount of information, Sigfox and LoRa are
excellent choices. When low latency is required, NB-IoT
and LoRa are the best options [25].
Regulatory
Compliance: is a crucial aspect of deploying LPWAN technologies
for IoT applications. Some key considerations for LPWAN regulatory compliance
are: spectrum Regulations, licensing Requirements, duty Cycle Limits,
transmission Power, data privacy, firmware updates, local regulations,
certifications, interference mitigation, geographical restrictions (Sigfox).
Reliability
and Redundancy: LPWAN offers reliability advantages for IoT
applications that prioritize long-range communication and power efficiency.
However, to ensure reliable operation, it is essential to assess the specific
requirements of applications, plan for network design and redundancy, and
implement best practices for device placement, security, and maintenance.
Redundancy is critical for maintaining connectivity in case of network
failures.
Data
Volume and Storage: LPWAN is typically designed for applications that
involve transmitting small amounts of data over long distances with low power
consumption. As a result, the data volume generated by LPWAN devices is
relatively low. However, LPWAN deployments can accumulate significant amounts
of data over time, and it is important to consider data volume and storage
requirements.
Longevity: In Sigfox, LoRa, and NB-IoT, end devices are
in low-power mode most of the time, thereby improving their battery life. The
NB-IoT end device consumes additional energy due to the need for synchronous
communication, QoS management, and its OFDM/FDMA access modes, which require
higher maximum current [26]. This reduces
the lifespan of the NB-IoT end device compared to Sigfox and LoRa.
Materials and methods
A methodological approach for implementing a Low-Power
Wide-Area Network (LPWAN) and evaluating coverage and connectivity for IoT
support services like The Thing Network (TTN) is presented. This work is part
of project 16/Q1306-PI “Internet de las Cosas y Redes LPWAN at the
Universidad Nacional de Misiones”, which is being carried on at the Faculty
of Exact, Chemical and Natural Sciences (FCEQyN) of the National University of
Misiones (UNaM), whose general objective is to establish modern and updated methods
usable in the field of the Internet of Things (IoT), addressing application
development support as well as objects localization.
Although LoRaWAN was originally designed to operate
across the frequency band defined by the International Telecommunication Union
(ITU) from 902 MHz to 928 MHz; in Argentina, there was a deviation from the
international definition. Instead, a segment of the Industrial, Scientific, and
Medical (ISM) band ranging from 905 MHz to 915 MHz was allocated for Advanced
Mobile Communications Service (SCMA) [27]. As a
result, Argentina uses the frequency band known as AU915 instead of the
originally planned US915 band. One disadvantage is that LoRa
transceivers must operate in half-duplex mode.
Considering the criteria for selecting LPWAN
technology, although conducting a quantitative cost analysis is challenging
given the current situation in our country, we have defined commercial
requirements, technological performance, and market availability to choose the
appropriate LPWAN solution.
Figure 2. Gateway installed at main
building of FCEQyN.
Figure 3. Deployment of a gateway at the
Biochemistry building, FCEQyN.
Hence, the implementation of a LoRaWAN network has
been defined to provide service to devices in the downtown area of the city of
Posadas. The gateways have been deployed on Raspberry Pi 3 Model A+ devices
(featuring a quad-core 1.4 GHz 64-bit processor, dual-band wireless LAN, and
Bluetooth 4.2/BLE) [28], and a LoRaWAN
concentrator board, the RAK831_915 [29]. This concentrator
board has the capability to simultaneously receive packets using different
spreading factors across multiple channels, making it a complete RF front-end
(see Figures 2 and 3). The RAK831 includes the SX1301 digital baseband chip
from Semtech, specifically designed for providing
gateway capabilities in ISM bands. The external RAK LoRaWAN antennas operate in
the 860-930MHz range and have a gain of 5.8dBi. IP network connectivity is
provided by the National University of Misiones.
In Posadas city, different mobile nodes have been used
for normal operation control and coverage testing. The nodes assembled at
FCEQyN consist of an Arduino Pro Mini (ATMEGA328P) board serving as the
processing unit, interconnected with an RFM85W 915 MHz chip functioning as the
radio interface (Fig. 4). Additionally, a commercial LoRa
node, Lopy v1.1[30] equipped with a Semtex 1272 transceiver
mounted on a Pycom expansion board v2.1 [31], has also been
employed (Fig. 5).
Figure 4. Nodes assembled at FCEQyN
(Arduino Pro Mini + RFM95).
Figure 5. Lopy
v1.1 Pycom Expansion Board v2.1.
The LoRaWAN network
transmits data between sensor nodes and base stations installed in FCEQyN
buildings, where the information is forwarded to The Things Network's backend
services. The mission of The Things Network is to create and maintain an open,
global, and decentralized Internet of Things (IoT) infrastructure that enables
the connectivity of low-power IoT devices. The primary function of The Things
Network is to provide a LoRaWAN-based network infrastructure that allows IoT
devices to connect wirelessly over long distances while consuming minimal
power. It achieves this by deploying and maintaining a network of LoRaWAN
gateways and by developing and maintaining open-source network software for
efficient device management, security, and routing. Additionally, TTN is an
open platform for device registration, implementing all the necessary backend
services for the operation of LoRaWAN base stations, where it collects,
formats, and transparently forwards the information generated by different,
making IoT technology more affordable and accessible for various applications.
Results
From the SWOT (Strengths, Weaknesses, Opportunities,
and Threats) analysis of the technology considered appropriate for the project,
certain conclusions have been drawn:
·
LoRaWAN offers cost-effective end devices and the
possibility of implementing private networks without the need for
subscriptions.
·
These features eliminate the need for subscriptions,
provide extensive coverage, and offer low power consumption.
·
Security concerns have been addressed through new
versions of LoRaWAN, improving its overall security posture.
·
Scalability can be optimized by synchronizing
low-power transmission with low-cost, more intelligent Medium Access Control
(MAC) solutions.
·
The primary threat will continue to be external
interference, as LoRaWAN operates in unlicensed bands. This is a matter to
consider for future technologies to be developed in the near future.
Using mobile nodes, the
streets of Posadas city have been traversed to verify the functionality of the
deployed network, ensuring its normal operation and enabling access for users
duly authenticated by TTN. This aims to prevent functional errors in the
deployed network, which occur when it does not conform to the requirements
defined and validated by the standards. The measurement of network coverage and
RSSI have been carried out using the TTNMapper tool [32]. TTNMapper is a tool commonly used
to map and analyze the coverage and performance of TTN's LoRaWAN networks. It
allows users to collect data from LoRaWAN nodes as they move around a specific
area, typically a city or region, and record information about the network's
signal strength and coverage. The data collected by TTNMapper
helps to visualize the network's performance, identify areas with weak or
strong coverage, and make informed decisions about optimizing their LoRaWAN
deployments. In fact, it is a very valuable tool for planning and improving the
efficiency of LoRaWAN networks.
For a better
differentiation and visualization of the results obtained in this work, the
receptions at each of the gateways have been indicated in Figures 6 and 7.
As part TTN's global IoT
network, the area of coverage shown by the gateways installed at UNaM has
extended beyond the downtown area which is defined as the potential customer
zone for the prospective LoRaWAN network.
In NLOS (non-line of
sight) areas due to the presence of buildings, the covered radius has reached
up to 4.5 kilometers from the gateways. This suggests that the network can
penetrate obstacles to some extent, allowing devices to communicate even when
there is no direct line of sight. In LOS (line of sight) situations, where most
of the signal propagation occurs over the Paraná River or in open fields, the
maximum distance reported by TTNMapper has been 13
kilometers.
Figure 6. TTNMapper
Report of Linked Nodes (FCEQyN Central).
Figure 7. TTNMapper
Report of Linked Nodes (Biochemistry building).
Conclusion
and Future Work
In this article, we have
thoroughly explored the Sigfox, NB-IoT, and LoRaWAN technologies,
providing insights into their advantages and challenges. Following a
comprehensive SWOT analysis that took into account economic and situational
factors, we successfully deployed two TTN Gateways within the facilities of the
FCEQyN. This LoRaWAN network has been in continuous operation since early 2017,
serving both the wider community and IoT solution developers.
The LoRa nodes developed
within the FCEQyN have demonstrated remarkable efficiency, offering extensive
coverage and a prolonged lifespan at a reasonable cost compared to parallel
commercial solutions that we have tested. Leveraging two gateways connected to UNaM's IP network, along with mobile nodes, we have
achieved impressive coverage, reaching up to a 4.5 km radius in non-line of sight
(NLOS) conditions and up to 13 km in line of sight (LOS) conditions.
TTNMapper graphics have illustrated that link performance tends
to decrease as distance increases, particularly in the presence of obstacles
like buildings and large trees.
Regarding scalability, the
results indicate that a single LoRaWAN cell holds the potential to serve
numerous clients transmitting small data payloads per day. Nevertheless,
devices with higher data traffic requirements should be located closer to the
base station, while fewer devices can operate effectively at greater distances.
This scenario necessitates more efficient management of data rates employed by
end nodes, as only a limited number of nodes operating at low data rates can be
accommodated. Additionally, the use of message acknowledgments (ACKs)
represents a factor limiting the scalability of the LoRaWAN cell.
LoRaWAN has indeed evolved into a crucial enabling
technology for IoT (Internet of Things) projects at the National University of Misiones.
Its distinctive ability to offer long-range, low-power connectivity has played
a pivotal role in fostering the development and implementation of IoT
applications across various domains within the city of Posadas. Moreover, this
technology has paved the way for exciting opportunities in research,
innovation, and real-world applications, effectively turning IoT into a
tangible reality within our academic setting.
In addition to its practical advantages, LoRaWAN has
also sparked a wave of academic and industrial interest. Our university has
witnessed a surge in research activities related to IoT, with students and
faculty members exploring innovative applications and solutions. This
technology has facilitated collaboration with local businesses and government agencies,
as they also recognize its potential to address real-world challenges.
In conclusion, LoRaWAN has become an integral part of
our IoT ecosystem, driving advancements in technology, research, and practical
applications. Its long-range, low-power connectivity has empowered us to
address diverse challenges and opportunities within our academic environment
and the broader community of Posadas. As we continue to harness the potential
of this technology, we look forward to further innovation and transformative
impacts on our region's IoT landscape.
Looking ahead, we have identified a future task: the
necessity to install a gateway to the west of the city of Posadas. This step
aims to validate the importance of redundancy in projects of this nature,
further enhancing the robustness and reliability of our IoT network
infrastructure.
Acknowledgments
The authors of
this article would like to express their sincere thanks to the IT and
Communications team for their proactive approach regarding physical facility
access, deployment, installation, and the configuration of the FCEQyN firewall.
Their dedication has been instrumental to ensure the overall functionality of
the system.
References
[1] «State of the IoT 2020: 12 billion IoT
connections, surpassing non-IoT for the first time», IoT Analytics, 19
de noviembre de 2020. https://t.ly/ZTJWF (accedido 17 de agosto de 2023).
[2] «Overview of LTE enhancements for cellular IoT».
https://t.ly/fqmWP (accedido 6 de junio de 2023).
[3] U. Raza, P. Kulkarni, y M. Sooriyabandara,
«Low Power Wide Area Networks: An Overview», IEEE Commun. Surv. Tutor.,
vol. 19, n.o 2, pp. 855-873, 2017, doi: 10.1109/COMST.2017.2652320.
[4] A. M. Baharudin y W. Yan, «Long-range
wireless sensor networks for geo-location tracking: Design and evaluation», en 2016
International Electronics Symposium (IES), sep. 2016, pp. 76-80. doi:
10.1109/ELECSYM.2016.7860979.
[5] O. Vondrouš, Z. Kocur, T. Hégr, y O. Slavíček,
«Performance evaluation of IoT mesh networking technology in ISM frequency
band», en 2016 17th International Conference on Mechatronics - Mechatronika
(ME), dic. 2016, pp. 1-8.
[6] «Generalidades sobre las asignaciones de frecuencia».
https://t.ly/kjzXm (accedido 8 de junio de 2023).
[7] «Coverage», Sigfox 0G Technology. https://t.ly/HrHkP
(accedido 6 de junio de 2023).
[8] «Homepage - LoRa Alliance®». https://lora-alliance.org/
(accedido 6 de junio de 2023).
[9] Y.-P. E. Wang et al., «A Primer
on 3GPP Narrowband Internet of Things (NB-IoT)». arXiv, 13 de junio de 2016.
doi: 10.48550/arXiv.1606.04171.
[10] «Semtech Semiconductor, IoT Systems and Cloud
Connectivity | Semtech». https://www.semtech.com (accedido 8 de junio de 2023).
[11] «The Things Network». https://t.ly/QTjoH (accedido 16 de mayo de
2022).
[12] «Standardization of NB-IOT completed». https://t.ly/slPyq
(accedido 6 de junio de 2023).
[13] R. & S. International, «Internet de las cosas en banda
estrecha». https://t.ly/jHTkb (accedido 6 de junio de 2023).
[14] F. A. Aoudia, M. Gautier, M. Magno, M. L.
Gentil, O. Berder, y L. Benini, «Long-short range communication network
leveraging LoRaTM and wake-up receiver», Microprocess.
Microsyst., vol. 56, pp. 184-192, feb. 2018, doi: 10.1016/j.micpro.2017.12.004.
[15] A. Ikpehai et al., «Low-Power
Wide Area Network Technologies for Internet-of-Things: A Comparative Review», IEEE
Internet Things J., vol. 6, n.o 2, pp. 2225-2240, abr. 2019,
doi: 10.1109/JIOT.2018.2883728.
[16] M. A. A. Khan, H. Ma, S. M. Aamir, y C. A.
Baris, «Experimental Comparison of SNR and RSSI for LoRa-ESL Based on Machine
Clustering and Arithmetic Distribution», 2022.
[17] «What is LoRaWAN® Specification», LoRa
Alliance®. https://t.ly/ImS5_ (accedido 25 de febrero de 2022).
[18] R. Trüb, R. Da Forno, T. Gsell, J. Beutel, y
L. Thiele, «Demo Abstract: A Testbed for Long-Range LoRa Communication», en 2019
18th ACM/IEEE International Conference on Information Processing in Sensor
Networks (IPSN), abr. 2019, pp. 342-343.
[19] B. Błaszczyszyn y P. Mühlethaler, «Analyzing
LoRa long-range, low-power, wide-area networks using stochastic geometry», en Proceedings
of the 12th EAI International Conference on Performance Evaluation
Methodologies and Tools, mar. 2019, pp. 119-126. doi: 10.1145/3306309.3306327.
[20] R. Agrawal et al.,
«Classification and comparison of ad hoc networks: A review», Egypt. Inform. J., vol. 24, n.o 1, pp.
1-25, mar. 2023, doi: 10.1016/j.eij.2022.10.004.
[21] T. Miyamoto, S. Narieda, T. Fujii, y H.
Naruse, «Measurement of Sub-GHz Band LPWA Radiowave Propagation on Each Floor
in Indoor Environment», en 2023 International Conference on Information
Networking (ICOIN), ene. 2023, pp. 85-88. doi: 10.1109/ICOIN56518.2023.10048939.
[22] A. Malik y R. Kushwah, «A Survey on Next
Generation IoT Networks from Green IoT Perspective», Int. J. Wirel. Inf.
Netw., vol. 29, pp. 1-22, mar. 2022, doi: 10.1007/s10776-021-00549-0.
[23] J. C. Liando, «Experience of LoRa low power
wide area network», Nanyang Technological University, 2019. doi:
10.32657/10220/47662.
[24] K. Mekki, E. Bajic, F. Chaxel, y F. Meyer, «A
comparative study of LPWAN technologies for large-scale IoT deployment», ICT
Express, vol. 5, n.o 1, pp. 1-7, mar. 2019, doi:
10.1016/j.icte.2017.12.005.
[25] Rasveen, S. Agrawal, K. Chopra, y S. Kumar,
«Coverage and Latency Analysis for NB-IoT in Uplink Transmission», en 2022
International Conference on Decision Aid Sciences and Applications (DASA),
mar. 2022, pp. 330-334. doi: 10.1109/DASA54658.2022.9765226.
[26] S.-M. Oh y J. Shin, «An Efficient Small Data
Transmission Scheme in the 3GPP NB-IoT System», IEEE Commun. Lett., vol. 21, n.o 3, pp.
660-663, 2017, doi: 10.1109/LCOMM.2016.2632128.
[27] «Informe_consulta_publica_de_espectro_02.pdf», informe consulta
publica de espectro. https://t.ly/WJD8f (accedido 3 de agosto de 2023).
[28] R. P. Ltd, «Buy a Raspberry Pi 3 Model B», Raspberry Pi.
https://t.ly/qNAxY (accedido 27 de julio de 2023).
[29] «RAK831 WisLink LPWAN Concentrator Datasheet | RAKwireless
Documentation Center». https://t.ly/cNINM (accedido 27 de julio de 2023).
[30] «LoPy». https://t.ly/aARTM (accedido 15 de agosto de 2023).
[31] «Expansion Board 2». https://t.ly/b-F2R (accedido 15 de agosto de
2023).
[32] «TTN Coverage». https://t.ly/0qwCx (accedido 16 de agosto de
2023).