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Capacity Improvement in 5G Networks Using Femtocell

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Allocation of resources between femtocell and macrocell is essential to counter the effects of interference in the dense femtocell. The significant increase in the number of internet users and the demand for higher data capacity per user mandates the development of complex and expensive telecommunication infrastructure that includes spectrum and power management, increased operation power and high-quality. In this work, we investigate the performance of femtocells in outdoor and indoor space based on the network’s capacity and resource management by extensive numerical modeling and simulations for different conditions of user’s location and femtocells in one cell.
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Vol.:(0123456789)
Wireless Personal Communications
https://doi.org/10.1007/s11277-019-06134-2
1 3
Capacity Improvement in5G Networks Using Femtocell
MohammadGhanbarisabagh1 · GobiVetharatnam2· EliasGiacoumidis3·
SoheilMomeniMalayer4
© Springer Science+Business Media, LLC, part of Springer Nature 2019
Abstract
Allocation of resources between femtocell and macrocell is essential to counter the effects
of interference in the dense femtocell. The significant increase in the number of internet
users and the demand for higher data capacity per user mandates the development of com-
plex and expensive telecommunication infrastructure that includes spectrum and power
management, increased operation power and high-quality. In this work, we investigate the
performance of femtocells in outdoor and indoor space based on the network’s capacity
and resource management by extensive numerical modeling and simulations for different
conditions of user’s location and femtocells in one cell.
Keywords Femtocell· 5G· Power control· IoT· Telecommunications market·
Interference
1 Introduction
Presently, the proposed technologies for 5G and the internet-of-things (IoT) for increas-
ing and optimizing spectrum resources and cell’s density includes massive multiple-
input multiple-output (MIMO), spatial modulation [1], native support for M2M for
a massive number of connected devices with low throughput and for low power and
latency, device centric architecture [2], and visible light communication [3]. They are
being extended to be applied for the increase and the growth in cell’s intensity. With
remarkable surge in smartification and the internet and cloud cache, new modulation
scheme have been noticed significantly. On the other hand, this increasing require-
ment needs more development in software, hardware and base station. As the proposed
* Mohammad Ghanbarisabagh
m.ghanbarisabagh@iau-tnb.ac.ir; m.ghanbarisabagh@gmail.com
1 Department ofElectrical Engineering, Faculty ofElectrical Engineering andComputer Sciences,
Islamic Azad University North Tehran Branch, Tehran, Iran
2 Department ofElectrical andElectronic Engineering, Lee Kong Chian Faculty ofEngineering
andScience, University Tunku Abdul Rahman, KualaLumpur, Malaysia
3 The Rince Institute, School ofElectronic Engineering, Dublin City University, Glasnevin 9,
Dublin, Ireland
4 International Business School, Zahony Utca 7, Budapest1031, Hungary
M.Ghanbarisabagh et al.
1 3
technology has the highest compatibility with current technologies it can decrease costs
leading to higher speed, better quality, and delay elimination.
Using higher frequencies to decrease the waves is essential to decrease the penetra-
tion distance between the user and the base station resulting in power resource man-
agement and signal quality optimization which has further flexibility in network archi-
tecture to decrease expenses [4]. This causes a better presentation of support in more
dense parts of the network through the application of small cells backhaul problems
[5] could be less beside the increase in system’s security [6] capability and the net-
work capacity. Nowadays, femtocells are noticed significantly in cellular indoor network
due to their easy setup and maintenance, less expenses and better coverage compared to
other existing approaches such as repeater and das [7]. They also have resources man-
agement capabilities, security and less pack loss in comparison with Wi-Fi. But is there
any expectation of development for their application in all areas in the 5G?
The most critical problem of femtocells is their interference management. If interfer-
ence could be decreased through proper approaches, femtocells could be used instead
of increasing the base stations power, which comes with its associated setup expenses
and high maintenance. For cross tier interference management there are methods such
as Femto-aware spectrum management, clustering of femtocells [8], cognitive [9], beam
subset selection strategy [10], fractional frequency reuse [11], collaborative frequency
scheduling [12] and power control. The last two methods have the least complexity and
the highest efficiency. Power control approach can be combined with beamforming to
avoid power wastage in space or alternately we could increase the beam power in the
desired direction.
With the large increase of population in the cities, one of the challenges being faced is
the inability of microcells to provide coverage in populated areas. In addition to that, the
proliferation of smart devices with 5G and coming of IOT in wireless cellular technologies
compared to LPWAN, further aggravates this challenge. Consequently, the network’s archi-
tecture must be optimized to decrease expenses and increase the speed and smartification
[13]. For instance, in a smart city, one of the most important issues is smart traffic manage-
ment. Here, cellular tracking [14] of vehicles can be done at a lower cost instead of costly
GPS devices and GNSS satellites. Through this better traffic regulations, security, more job
opportunities and telecommunication network optimization would be achieved.
The motivation of this work is to decrease the cost by managing the interference
between femtocells and macrocells properly, and increasing the usage of indoor and out-
door femtocells.
Mobile Mega-Operators are promoting femtocells very seriously in order to decrease
tariffs, increase QOS and not to lose future consumption market. Through proper interfer-
ence management, femtocells can have high influence. Moreover, using indoor and outdoor
femtocells causes cost elimination and macrocells restriction.
Femtocells are imagined in indoor space in various studies and both path lost [15, 16],
and interference scenarios have been studied for indoor and outdoor users. However, out-
door femtocells are not noticed enough due to their less usage. In future tele-communica-
tion generation, outdoor femtocells must be used according to appropriate distance with
MBSs specially, beamformed outdoor femtocells. For instance, Swisscom and Ericsson
companies have used city manholes for outdoor femtocells. The way to increase the net-
work’s capacity with much lower costs will be more economical. Therefore, the main con-
tribution of this work is to improve the simulation results by special attention to beam-
formed outdoor femtocells.
The organization of the paper is as below:
Capacity Improvement in5G Networks Using Femtocell
1 3
In Sect.2 the system analysis and modeling has been discussed. This section determines
user inputs, system parameters and calculating path-loss based on population, urban den-
sity and telecommunication standards. Next section shows the simulation results. This sec-
tion mean CQI Based on SINR, demand based on the four important users, the amount of
added capacity coefficient to distance ratio without specifying the amount of bandwidth
allocated, spectrum efficiency in terms of distance ratio, and comparing MBS and Femto-
cells using a distance of more than 175m. Finally, in the last section the conclusion of the
work together with the future work has been discussed.
2 System Analysis andModeling
In this standard, outdoor wall loss is 20dB and indoor loss is 5dB. This method is more
appropriate for modeling.
(a) Fig.1 shows the coverage provided by mobile base stations (MBS) in Tehran. Based
on current MBS locations, significant parts of Tehran do not have adequate coverage.
Femtocells within this area can assist to improve the coverage of Tehran. Urban density
indicator can be used to approximate the building densities and indirectly the locations
of femtocells. With the consideration of beam forming for outdoor femtocells, the
number of users can be estimated and based on related variants, to base stations and
spectrum features modeling.
Using signal-to-noise-interference ratio variant, the network capacity and rate of
information transfer can be studied. Firstly, the path-loss information as calculated by
Fig. 1 MBS coverage
M.Ghanbarisabagh et al.
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different method is assessed. The best method is to use the model based on empirical
measurements and transmitter’s features, such as Hata & Okumura model [17], or using
pre-existing standards.
In this method waste gets estimated more comprehensively according to macro feed-
backs. The recommended amount is listed in the following for macrocell outdoor user,
femtocell outdoor user, macrocell indoor user and femtocell indoor user, respectively.
(b) The following formula indicates the calculation of SINR for MBS user in subcarrier
k, in which
PM,k
and
Gm,M,k
are the M MBS power and the antenna gain respectively
and M is the neighboring MBS power. N0 is the noise power spectrum density per
subcarrier spacing.
Furthermore, the interference of the femtocells is included.
In order to simplify the calculations we can consider this formula based on one exist-
ing main MBS and ignore the interference of other MBSs. Therefore, considering
the number of MBSs in city space B and calculating their advantage through beam
formed antenna sites and dividing users into categories of outdoor and indoor, formu-
las5 and 6 can be rewritten as following. They indicate SINR for MBS indoor users,
femtocell indoor users, MBS outdoor users and femtocell outdoor users respectively.
From these, the consequences of simulation can be studied in terms of accuracy.
(1)
PLmo(dB)=15.3 +37.6LOG R
(2)
PLfo(dB)=15.3 +37.6LOG R
(3)
PLmi(dB)=15.3 +37.6LOG R +LOW
(4)
PL(dB)=15.3 +37.6LOG R +Liw
(5)
SINR
m,k =
P
M,k
G
m,M,k
N
0
Δf+
M
P
F,k
G
m,F,k
+
M
P
M
,k
G
m,M
,k
(6)
f,k =
F,k
f,F,k
N
Δf+
P
G
+
P
G
(7)
SINR
mh,k =
P
M,k
G
mh,M,k
N
0
Δf+
F
P
F,k
G
fh,F,k
(8)
SINR
fh,k =
P
F,k
G
fh,F,k
N
0
Δf+P
M,k
G
mh,M,k
(9)
SINR
mc,k =
P
M,k
G
mc,M,k
N
0
Δf+
B
P
Fc,k
G
fc,B,k
(10)
SINR
fc,k =
P
F,k
G
fc,F,k
N
0
Δf+P
M,k
G
mc,M,k
+
B
P
Fc,k
G
fC,B,k
(11)
G=10
PL
10
Capacity Improvement in5G Networks Using Femtocell
1 3
Specific parameters are required in order to perform the modelling, including the
number of points available, users and the ratio of indoor femtocells to urban cells
among others. Therefore, using the standard of [18] the cell features are identified
according to the Table1.
Moreover, calculated SINR can be used in the SHANNON formula to determine the
network capacity.
(c) For control of power, the system is defined based on population, urban density and
telecommunicate standards. Next, an estimate is made and the network is designed
according to the possibility of user’s presence in each areas. These values may change
floatingly. The system architecture is shown in Fig.2.
It is important to consider that 65% of this load is on indoor section based on pre-
sented statistics. Furthermore, 35% of urban users and 65% of indoor users are not satis-
fied with the presented services. Femtocells are required to move towards this section’s
supply. Moreover, this can be compared to user’s need service’s quality and be included
in the calculations related to power. This results in 30, 23, 35 and 12% for indoor MBS
user, indoor femtocell user, outdoor MBS user and outdoor femtocell user, respectively.
Matlab was used for modeling [19] and it has been optimized for the current usage as
shown in Fig.3.
For the purpose of simulation in urban space, Tehran is considered as an example.
Since Tehran’s building’s density is R122, it could be said that a piece of infrastructure
land of 250 square would be considered on the one hand. In this model density has been
simulated according to the number of existing house under MBS coverage. The gather-
ing of indoor femtocells is placed mostly further than MBSs in the simulation. Since,
(12)
Cm,k
f.log
2(
1+∝SINR
m,k)
Table 1 System parameters System parameter Value/range
Macrocell radius 500m
Macrocell transmission power 46dBm
Carrier frequency 2GHz
Bandwidth 20MHz
White noise power density − 174dBm
Number of indoor femtocells 24
Number of outdoor femtocells 6
Number of macrocell active user 90
Number of femtocell active user 90
Fig. 2 System architecture User
inputs
calculate
path-loss
calculate
SINR
SINR-to-CQI
Mapping
OUTPUTS
& RESULTS
M.Ghanbarisabagh et al.
1 3
the proportion of a street’s area to houses is 1– 5, the number of urban femtocells has
been allocated based on this proportion.
Based on beamforming in the length of street, a wide range of urban users are allocated
to femtocells. The number of users is based on active 1–5. However, the user’s proportion
will be increased very soon in Tehran.
In the identified section of Fig.4 the features related to user number 67 who is an out-
door one are calculated.
3 Simulation Results
From the simulation, SINR and the distance relevant to users were recorded. The data was
gathered and then for each group, CQI was extracted according to Fig.5; [20] and Table2.
Based on this, the average was achieved and eventually the Fig.6 was drawn.
Based on weight importance for each group and the percentage of estimated accidental
users according to area integral between 50m from MBS in Table3, Fig.7 is drawn.
On the distance, the amount of added capacity coefficient to the network by femtocells,
and using Eq.12 has been calculated cumulatively as shown in Fig.8.
Fig. 3 Simulated cell
Capacity Improvement in5G Networks Using Femtocell
1 3
Fig. 4 Marking user number 67
Fig. 5 SINR-to-CQI mapping
M.Ghanbarisabagh et al.
1 3
This coefficient has been achieved without specifying the amount of bandwidth allo-
cated and it is observed that the efficiency of indoor femtocell in increasing network capac-
ity of 6 is more than urban femtocell. Spectrum efficiency based on CQI, shown is Table4,
and distance of urban femtocell’s users used by the main base station has been illustrated
in Fig.9. It shows that in the distance of 135m, femtocell has higher spectrum efficiency.
As shown in Fig.10, half of the users keep a distance of more than 175m from MBS.
Through this, the CQI for outdoor femtocells is more than the CQI for the MBS. In such
a distance, outdoor femtocells have almost equal capacity with indoor femtocells in fewer
radiuses. Therefore, outdoor femtocells can increase the network capacity effectively.
Table 2 SINR-to-CQI mapping
SINR − 6.7 − 4.7 − 2.3 0.2 2.4 4.3 5.9 8.1 10.3 11.7 14.1 16.3
CQI index 1 2 3 4 5 6 7 8 9 10 11 12
Fig. 6 Mean CQI based on SINR
99
7
5
3
2
999
8
6
3
999
4
6
777
0
2
4
6
8
10
050 100 150 200 250
MEAN CQI
DISTANSE FROM MBS
MACRO UE IN MACRO UE OUT
FMTO UE IN FEMTO UE OUT
Table 3 Percentage of estimated
accidental users Distance from MBS 0 50 100 150 200 250
Percentage of population 0 4 12 20 28 36
Fig. 7 Demand based on the four
important users
0
1
2
3
4
0416 36 64 100
DEMAND
POPULATION
MACRO UE IN MACRO UE OUT
FMTO UE IN FEMTO UE OUT
Capacity Improvement in5G Networks Using Femtocell
1 3
However, this distance can be changed by changing MBS transmission power. If the num-
ber of outdoor femtocells and indoor femtocells are 5 and 21, respectively, by consider-
ing the cost of each outdoor femtocells, each indoor femtocell and each MBS as 1.4k$,
Fig. 8 The amount of added
capacity coefficient to distance
ratio without specifying the
amount of bandwidth allocated
0
100
200
300
400
500
600
050 100 150 200 250
ADDED CAPACITY COEFFICIENT
DISTANCE FROM MBS
INDOOR OUTDOOR
Table 4 CQI to efficiency
mapping CQI index Modulation Code rate × 1024 Efficiency
0 Out of range
1 QPSK 78 0.1523
2 QPSK 193 0.3770
3 QPSK 308 0.6016
4 QPSK 449 0.8770
5 QPSK 602 1.1758
6 16QAM 490 1.9141
7 16QAM 616 2.4063
8 64QAM 466 2.7305
9 64QAM 567 3.3223
10 64QAM 772 4.5234
11 64QAM 873 5.1152
12 64QAM 948 5.5547
13 256QAM 772 6.0312
14 256QAM 948 7.3984
IS 256QAM 975 7.6171
Fig. 9 Spectrum efficiency in
terms of distance ratio
0
0.5
1
1.5
2
2.5
3
50 100 150200 250
SPECTRUM EFFICIENCY
DISTANCE FROM MBS
MACRO FEMTO
M.Ghanbarisabagh et al.
1 3
1.19k$ and 30 k$, respectively [21], the total cost and capacity coefficient can be perse-
cuted in Fig.10.
Figure 10 shows by using the distance of more than 175m, outdoor femtocells can
achieve higher capacity with lower cost.
4 Conclusion andFuture work
Although femtocells are suitable for both indoor and outdoor applications, the demand for
outdoor femtocells is less than half of indoor femtocells. By using outdoor femtocells of
more than half of the MBS radius, the performance shows very good spectruonm and sig-
nal quality. Using the CQI coefficient, we can manage and release MBSs while increasing
network capacity so that more users could be served with higher bandwidth or used for
cellular tracking for each vehicle in a smart city. Outdoor Femtocells are appropriate and
efficient solution for accurate and extensive cellular vehicle tracking which can create great
potential and revenue. Decreasing the costs of femtocell’s production would be a good
challenge in the near future as there is a strong need to use the femtocells in the network.
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Publisher’s Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and
institutional affiliations.
Mohammad Ghanbarisabagh was born in Tehran, Iran. He obtained
his B.Eng degree in Electronics Engineering in 1990. He received his
M.Eng.Sc degree in Wireless Communications Engineering from Iran
University of Science and Technology in 1999. He then received his
Ph.D. degree in Optical Communications Engineering from Multime-
dia University, Malaysia in 2011. He was a Senior Lecturer in the
Department of Electrical Engineering, Faculty of Engineering, Univer-
sity of Malaya in Malaysia from April 2012 till September 2013. Since
October 2013, he joined as an Assistant Professor to the Department of
Electrical Engineering, Faculty of Electrical Engineering and Com-
puter Sciences, Islamic Azad University North Tehran Branch, in Teh-
ran, Iran. Dr. Ghanbarisabagh is a CEng as well as a member of IET.
He is a member of editorial board for some journals and is a reviewer
for more than 15 ISI Q1 journals like IEEE Transactions on Circuits
and Systems I: Regular Papers, IEEE Journal of Lightwave
M.Ghanbarisabagh et al.
1 3
Technology, IEEE Photonics Journal, IEEE Sensors Journal, OSA/Optics Express, OSA/Optics Letters,
OSA/Applied Optics, OSA/ Journal of Optical Communications and Networking, Elsevier/Optical Fiber
Technology, Taylor & Francis/Fiber and Integrated Optics, and …;. His research interests include the field
of wireless communications especially in OFDM and optical communications especially in Optical OFDM.
Gobi Vetharatnam was born in Malaysia. He obtained his B.E. degree
in Electrical Engineering in 1998 from University of Malaya. He
received his M.Eng.Sc and Ph.D in Engineering from Multimedia Uni-
versity in 2003 and 2011, respectively. He is currently an Associate
Professor in Lee Kong Chian Faculty of Engineering and Science, Uni-
versiti Tunku Abdul Rahman, in Sungai Long, Malaysia. He is a PEng
as well as a senior member of IEEE. His research interests include the
field of wireless communications, microwave remote sensing and radar
system, where he focus on the antenna system for these applications.
Elias Giacoumidis is a Marie-Curie Fellow at Dublin City University
& SFI CONNECT Research Centre of Ireland. His project tackles the
“capacity crunch” in optical fiber communications (EPIC: Energy-effi-
cient & Phase-Insensitive Coherent Communications). He has also
recently joined Xilinx-Ireland as a visiting-scholar for the realtime
implementation of machine learning based fiber nonlinearity compen-
sation. He has previously worked for various prestigious optical com-
munications research groups: Heriot-Watt University (cybersecurity
group), University of Sydney CUDOS (deputy photonics project
leader), Aston University, Bangor University (PhD scholarship), Ath-
ens Information Technology, and Telecom-ParisTech, where he was
also teaching optical system modelling. His research involves balanced
theoretical and experimental exploration in high-capacity optical trans-
mission systems with specialization in key modern digital signal pro-
cessing modulation techniques (OFDM, CAP, PAM-4 etc.) and nonlin-
ear photonics (e.g. Brillouin filtering and amplification) for
next-generation local, access networks and flexible long-haul optical
communications. Dr Giacoumidis is the principal investigator of the world’s-first direct-detected optical
Fast-OFDM transmission system. He was the first to implement digital-based machine learning in optical
communications (coherent optical OFDM) for fiber nonlinearity compensation. Dr Giacoumidis was nomi-
nated an outstanding reviewer of 2016 for IEEE Journal of Lightwave Technology.
Soheil Momeni Malayer obtained his B.Eng degree in Electrical Engi-
neering from University of Science and Culture, Iran in 2015. He then
received his M.Eng.Sc degree in Wireless Communications Engineer-
ing under Dr. Mohammad Ghanbarisabagh supervision from Islamic
Azad University North Tehran Branch, Iran in 2018. He is currently
studying German language at International Business School, Hungary.
His research interests include radio resource management and interfer-
ence management in mobile communications networks.
... There are many techniques for interference management such as: cognitive [6], Femtoaware management [7], [8], clustering of Femtocells [9], power control [10], frequency allocation (FFR) [11], [12] and resource scheduling algorithm [13], [14]. In our paper we describe the traditional combination algorithm [15], [16], that combines between the fixed power control algorithm and (FFR) algorithm to improve SINR. Then we propose an algorithm that combines between the dynamic fractional frequency algorithm, the fixed power control algorithm, and the resource scheduling algorithm which can select the best frequency allocation in the cell which can increase the SINR, throughput and reduces the interference from neighbor cells. ...
... In [14] the dynamic Fractional frequency reuse mechanism can select the best frequency allocation between the outer and inner regions. In [15], the resource scheduling algorithm can optimize the performance parameters of throughputs. (See Fig. 1). ...
... where the term is added for an indoor macro user to denote the penetration loss of the external wall. Similarly, the suggested model according to [15] for the case of an indoor and outdoor Femto-user is estimated, taking into account the penetration loss due to exterior and interior walls. Values of 7 and 15 dB are a good estimation of the penetration loss for internal and external walls, respectively. ...
Article
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The rapid increase in quality performance and high data rate make the small cell an attractive solution in the next generation of a cellular mobile network. The Femtocell is a small cell that can boost services to four or five users in low price, and it can guarantee high data rate and capacity within the indoor residential. The Macrocell is a base station with high power that can cover up to 200 miles of cell radius. The propagative of Femtocell over macrocell can cause interference between them as they use the same spectrum. In our paper, first we explain interference management algorithms; such as power control algorithm, Fractional Frequency Reuse (FFR) algorithm and resource scheduling algorithm. Also, we propose an algorithm for interference management that combines the fixed power control algorithm, Dynamic Fractional Frequency Reuse (DFFR) algorithm, and resource scheduling algorithm to mitigate the interference. Simulation results show that the proposed algorithm improves the signal to interference plus noise ratio (SINR), throughput and reduces the interference from neighbor cells.
... Femtocell nodes are plug and play nodes that are often installed by subscribers without considering the cell coverage area, which leads to cell overlap with neighboring femtocells; causing an increase intra cell (co-tier) interference. This interference problem is said to be the major technical problem of Macro-Femto HetNet [1,9,10,11], other problems include network security and handoff. There are works on mitigating interference in Macro-Femto cellular communication networks, but this particular research work used an enhanced active power control technique that was proposed in [1] for mitigating interference in Macro-Femto downlink transmission and evaluate it's performance. ...
... In [11] a dynamic power control technique called power control 1 (PC1) for mitigating interference was used. The technique adjust node transmission power based on the difference between computed UE signal-to-interference-plusnoise ratio ( ) and target UE SINR ( ), expressed in (2) ...
... As presented in [14] average data rate is obtained using (11). ...
Conference Paper
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Femtocells are overlayed on existing Macrocells to reduce cost of mounting expensive macrocell nodes, improve cellular network coverage, capacity and Data rate performance. However, Macro-Femto heterogeneous (HetNet) network has a major problem of co-tier and cross-tier interference, which hinders its optimal performance, especially when the network capacity expands. With emergence of 5G technologies, interference would become more consequential. This paper deployed an enhanced active power control (EAPC) technique in mitigating Macro-Femto interference along downlink transmission of 5G non-stand-alone (NSA) architecture. The EAPC technique when compared with APC and PC1 techniques respectively yielded: 65% and 37% higher home user equipment (HUE) data rate; 37% and 21% higher macro user equipment (MUE) data rate. EAPC average power usage compared to that of APC and PC1 conserved 54% and 22% Hen-gNB energy respectively. EAPC technique conserved 21% en-gNB energy when compared to APC, but was limited when compared with PC1 by 8%; which should be considered in further studies.
... The most successful strategy, however, is to use BSs with varying powers because adding spectrum is the simplest but least expensive method. When a cellular network is heterogeneous, it can offer increased capacity, increased coverage, and high data transfer (macro, pico, or femto) [8]- [10]. Cellular networks become more difficult to analyse using traditional techniques as a result of heterogeneity. ...
... Figure15 shows the average data rate in Mbps for the network shown in Figure 1. The data rate is directly proportional to the spectral efficiency (SE) as evident by (10). How efficiently bandwidth is utilized is termed spectral efficiency (SE). ...
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The coverage and capacity required for fifth generation (5G) and beyond can be achieved using heterogeneous wireless networks. This exploration set up a limited number of user equipment (UEs) while taking into account the three-dimensional (3D) distance between UEs and base stations (BSs), multi-slope line of sight (LOS) and non-line of sight (n-LOS), idle mode capability (IMC), and third generation partnership projects (3GPP) path loss (PL) models. In the current work, we examine the relationship between the height and gain of the macro (M) and pico (P) base stations (BSs) antennas and the ratio of the density of the MBSs to the PBSs, indicated by the symbol β. Recent research demonstrates that the antenna height of PBSs should be kept to a minimum to get the best performance in terms of coverage and capacity for a 5G wireless network, whereas ASE smashes as β crosses a specific value in 5G. We aim to address these issues and increased the performance of the 5G network by installing directional antennas at MBSs and omnidirectional antennas at Pico BSs while taking into consideration traditional antenna heights. The authors of this work used the multi-tier 3GPP PL model to take into account real-world scenarios and calculated SINR using average power. This study demonstrates that, when the multi-slope 3GPP PL model is used and directional antennas are installed at MBSs, coverage can be improved 10% and area spectral efficiency (ASE) can be improved 2.5 times over the course of the previous analysis [1]. Similarly to this, the issue of an ASE crash after a base station density of 1000 has been resolved in this study.
... Macrocells it is open-access BSs with a range of approximately 1 km to 20 km and a power output of around 20W. They employ committed backhaul and have a range of about 1 km to 20 km [4]. ...
... The reception between planned transmitter and receiver pairs is improved by increasing the capacity. The femtocells' insulation from neighbouring femtocell transmissions is lost as a result of penetration [4]. Assuming a constant receiving power objective without any fading and designating (resp. ...
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Due to the fact that the communication network signal is weak inside certain places where there are some barriers such as buildings, for example, it was necessary to use communication cells that cover the entire place by strengthening the signal and increasing the transmission capacity to accommodate the number of users by using Femtocells. The use of Femtocells is compatible with many communication systems, including the LTE communication system.
... However, the easiest way among all is adding more spectrum, but this method is not cost effective because adding more bandwidth makes the system more expensive. Thus, the only way to achieve high data transmission is to densify the network by creating heterogeneous network with multiple class of base stations such as large-scale BSs (Macro) and small-scale BSs (Pico) or even femto base stations [2][3][4][5] to boost the coverage and capacity. Thus, the important parameter of mobile wireless network is the SINR through which capacity can be increased When the cellular networks are densely deployed with multiple class of base stations like macro, pico, femto, or some kind of relays and remote radio heads (RRHs), or mixture of these then the cellular networks become complex enough to be treated for analysis due to heterogeneity with conventional methods of wireless communication. ...
... The evaluation of the Femtocell network in this study will be carried out by measuring signal-to-interference noise ratio (singer) and flat [26]. First, the power the user receives is obtained by calculating the Budge Link [27] ...
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The field of telecommunications technology has undergone significant changes in recent years, particularly with the development and commercial use of 4G and 5G technologies. As 5G technology becomes increasingly prevalent in Indonesia, it is important to explore the ideal network configurations that can achieve desired data rates in areas with high user densities. This study focuses on femtocell networks, which are compact base stations that require minimal power and are ideal for indoor use. Specifically, the study examines three alternative MIMO antenna scenarios, which are Multi-Input Multi-Output antenna designs that can improve data throughput. The study's simulation results indicate that a 16X16 MIMO design offers the best performance in achieving data rates of 1Gbps for all users in a high-density site. This design outperforms 4X4 and 8X8 MIMO arrangements in terms of data throughput, making it the ideal network configuration for femtocell networks in areas with high user densities. The findings of this study can be applied to the deployment and optimization of femtocell networks, which can improve network capacity and data rates for users in indoor environments. As 5G technology continues to advance, the findings of this study will be increasingly relevant and useful for optimizing network configurations and achieving desired data rates.
... The indiscriminate installation of femtocells by network user increases co-tier (intra-layer) and cross-tier (interlayer) interference in Macro -Femto HetNet. This interference is an undesired signal picked by neighboring network devices that hampers the optimal performance of cellular communication networks [2,[7][8][9]. Interference is classified into uplink co-tier, uplink cross-tier, downlink co-tier, and downlink cross-tier interference as depicted in Fig. 2 below. [10,11] Interreference mitigation techniques are therefore of great value to improve the quality-of-service (QoS) in femto cells [12]. ...
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When interference is reduced, the benefits of using a macrocell and femtocell heterogeneous network (Macro-Femto) heterogeneous network (HetNet) can be increased to their full potential. In this study, Enhanced Active Power Control (EAPC), Active Power Control (APC), and Power Control (PC1) interference mitigation strategies are applied, and their performances in uplink and downlink transmission of 5G Non-Stand-Alone (NSA) architecture are compared. According to the findings of a MATLAB simulation, the EAPC technique utilized a lower amount of transmit power for the Macro User Equipment (MUE), the Home User Equipment (HUE), and the femtocell logical node (Hen-gNB), in comparison to the APC and PC1 techniques. While PC1 approach required less en-gNB transmission power. The MUE, HUE, hen-gNB, and en-gNB throughput of the EAPC approach was much higher. This work will enable wireless system designers and network engineers know the appropriate technique to utilize to achieve desired Quality of Service (QoS) while conserving network resources.
... A connection of links to system-level simulation can be utilized to analyze the capacity of the sidelink V2V channel for LOS and NLOS communication together with the deployment parameters as specified in 3GPP Release 15 for LTE V2V and NR V2V. Another method that can be used to estimate the capacity of the V2V sidelink channel is proposed by Ghanbarisabagh et al. [54]. They used a parametrized model's motion and trajectory estimation for nonlinear least mean squares under-sample image sequences. ...
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Chapter
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Device-centric architecture is an aspect of fifth generation communication whereby devices/user equipment is able to directly communicate with other devices with minimal involvement by the base station (BS). However, devices that are not within their proximity area communicate with other devices (relay). In this paper, we propose a device-centric scheme for relay selection in a dynamic network scenario. In this scheme, once the communicating devices have reached the maximum distance threshold, they exchange neighbor tables and find common devices (relay) for further communication. In addition, we propose a new relay selection scheme for scenarios, where the devices have more than one device (relay) in common. The proposed relay selection scheme is based on several parameters, including signal-to-noise ratio (SNR), signal-to-interference plus noise ratio, residual battery power, buffer space, and reliability; this provides more reliable and efficient communication. The current relay schemes, including max–min and max–max, are network assisted; the network/BS decides the relay, which increases the load on the BS side. The BS selects relay based on channel state information or SNR, which does not provide efficient or reliable communication. Our proposed device-centric scheme depends less on the BS during relay selection, which reduces network overhead, and the relay selection scheme provides more efficient and reliable communication. A comparison with other relay selection schemes shows that our scheme is 30% more effective in each case.
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Conference Paper
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Two empirical indoor-to-outdoor path loss models to facilitate femtocell network deployment are derived from continuous wave power measurements. A large set of indoor-outdoor transmitter locations in two residential streets in an urban setting and operating at 900 MHz, 2 GHz, 2.5 GHz and 3.5 GHz have been used to derive the model parameters by using singular value decomposition (SVD). The path loss models have been compared and validated against existing models as well as independent measurement data and good comparison is shown. The root mean square error of the residual path loss data obtained from the measurement data, which directly relates to the channel shadowing characteristics, is compared and validated with known results and has led to new model parameters being proposed. The expressions derived from the modelling can be used in system-level simulators, as well as for shadowing interference analysis of two-tier heterogeneous networks operating in indoor-outdoor scenarios at or close to the operating frequencies considered. In this study, the models extend the operating frequency range compared to related models and introduce SVD as a convenient means of deriving parameters from measured path loss data.
Conference Paper
In this paper, we tackle the problem of resource management in macro-femtocell networks. Dense deployment of femtocells imposes several challenges for a cluster-based resource allocation. Some of those challenges are the trade-off between the level of offloaded traffic from macrocell and bandwidth allocated to femto-tier, the fair distribution of resources, and the mitigation of inter-cluster interference. To overcome these limitations, we propose a coalitional game to form clusters of femtocells that can reduce the resource allocation complexity. Stable clusters are formed based on the core model. Our proposal mainly consists of three components. Namely, a femtocell selection for public users, a coalitional game where cooperative femtocells are rewarded, and a Weighted Water Filling algorithm to allocate resources. Our solution is performed under a rewarding model, which is based on an ideal spectral efficiency and on an effective spectral efficiency. We compare the results of our rewarding model with a non-cooperative model, where femtocells work in closed access mode. Simulation results demonstrate that our proposal improves the femto-tier throughput and the satisfaction of femtocells subscribers.
Conference Paper
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