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With the rapidly growing traffic demand, the cellular industry is moving toward heterogeneity to fulfill the heavy traffic requirement. The existing heterogeneous networks are comprised of the Long-Term Evolution (LTE), LTE-Advanced (LTE-A), and other compatible access technologies. It has been identified that due to the shortage of capacity, cell performance can deteriorate. To deal with users’ requirements, the 5G heterogeneous network architectures comprising LTE-advanced access technology with the combination of comparatively low configured small base stations, and macro eNodeBs (MeNB) have been extended as a solution. Therefore, operators have introduced the 5G with the existing LTE Advanced Heterogeneous Network (5GLHN) where small cells such as Home eNodeBs (HeNBs) are deployed overlapping with the conventional macro eNodeB (MeNB). However, in highly dense and closely compacted 5GLHNs, the cell capacity can still be lower than what is on-demand, thus affecting the system throughput. This article proposes a framework to maximize the throughput in 5GLHNs through a Constriction Factor Particle Swarm Optimization (CFPSO) technique of cell association and load-balancing algorithm to enhance the throughput of the 5GLHN. The proposed approach is designed to offload the traffic of MeNB Users (MUEs) to the small cells (HeNBs). The convergence, cumulative distribution function of the UEs rate, average throughput, and allocation time are analyzed to evaluate the performance of the proposed CFPSO approach. Simulation results reveal that the throughput of the proposed approach is improved by up to 44.08% of the existing index-based approach and by 94.20 \% of the existing Matching with Minimum Quota (MMQ) approach.

LTE-A network offers data rates up to 1 Gbps which is 10 × faster than LTE catering to growing demand of users. LTE improves user experience by reducing latency and increasing bandwidth efficiency. The emerging services and key enhancements such as Further Enhancement of Downlink Multiple-Input Multiple-Output (MIMO), Heterogeneous Networks, and Carrier Aggregation (CA) in LTE-A has improved performance of LTE-A networks. Scheduling optimization still remains one of the biggest challenges in high speed data transmission network. Scheduling in LTE-A networks are performed at various levels; User Equipment (UE), Serving Gateway (SGW), Air Interface and eNodeB. Remote Radio Head (RRH) is an extremely specialized device installed at antenna of eNodeB for optical to electrical signal conversion, amplification of signals and Uplink and Downlink Scheduling. Resource scheduling at Antenna of eNodeB module is constituted as a significant research optimization area. This paper proposes a soft computing based scheduler for RRH. Results of proposed technique are evaluated on Fairness Index, Throughput, Spectral Efficiency and Rank Indicator Distribution. The proposed algorithm aims to improve performance of scheduling. From experimental results, it is observed that proposed model succeeds to achieve significantly better performance as compared to state-of-art algorithms.

Relaying technology is one of the LTE-A issue that is considered the area of concern of several researches. Thus LTE-Advanced with relays uses several enhanced techniques in order to improve network performance like cell throughput enhancement and coverage extension. LTE-Advanced is considered as a real evolution of the LTE as it develops new technologies that allow to meet the proposed targets. The Radio Resource Management (RRM) mechanism and relay selection method can greatly contribute to this aim. In this paper, we jointly consider the problem of relay selection and RRM in order to improve the coverage and performance of mobile broadband wireless access service. We give a detailed description of the adopted LTE-Advanced system model with multiple user equipments assisted by one evolved Node B and multiple Relay Nodes. It is important to point out that the microcell technique is jointly adopted in the proposed RRM scheme to provide a better performance. The Microcell technique is considered as a densification approach massively employed in 5G radio access network systems like femtocell and picocell. Call admission control problem is also taken into account mainly when a minimal rate is needed to guarantee user satisfaction. By numerical results, we show that our proposed method could be a better choice for LTE-Advanced standard as it represents a trade-off between the fairness and the user throughput.

Voice over long term evolution (VoLTE) in long term evolution-advanced (LTE-A) is gaining more and more popularity these days. However, the increasing demands of subscribers raise new challenges in wireless network to support large number of concurrent active users while maintaining the desired delay requirements. To realize the issue, this paper proposes an LTE-A capacity or eNodeB (eNB) capacity estimation model, i.e. defined as the number of simultaneous users for location-dependent diverse radio conditions. This proposed model incorporates different bundling mechanisms to utilize the radio resources efficiently. Then, optimal transmission parameters $$\alpha$$ , $$\alpha ^{'}$$ using packet bundling, $$\beta$$ , $$\beta ^{'}$$ using transmission time interval (TTI) bundling, and $$\eta$$ , $$\eta ^{'}$$ for mixed radio condition is derived to enhance the accommodation of a large number of users within an LTE-A cell. There has been almost no consideration in the existing research on LTE-A capacity estimation based on these aspects. Therefore this paper presents novel algorithms based on the proposed models that enable capacity estimation and optimization under diverse radio conditions. The LTE-A cell capacity obtained using the proposed algorithms can be further used as an important parameter for designing call admission control (CAC) in packet-switched wireless networks.

Long Term Evolution Advanced (LTE-A) is a broadband wireless technology that supports variety of services with different data rate. In order to achieve this the evolved Node B (eNB) uses different features provided in the 3GPP standards. Features like Carrier Aggregation (CA), Multiple input and Multiple output (MIMO) and Hybrid Automatic Repeat Request (HARQ) help to increase the throughput and spectral efficiency. In this paper, a novel two-level calendar disc algorithm with HARQ is introduced at the eNB for effectively scheduling real time and non-real time traffic with different service types. The algorithm also uses a burst profile management module that analyzes the current user profile and notifies the scheduler about the need to change in profile based on power boosting. The Calendar Disc Scheduler (CDS) is improved by adding HARQ retransmission index as a parameter in calculating the metric weight. The scheduler was tested for both adaptive and non-adaptive methods of HARQ in both synchronous and asynchronous modes. The proposed improved CDS scheduler was simulated with LTESim simulator and compared with calendar disc algorithm without HARQ improvements. Results show that the proposed scheduling method provides increased performance in terms of goodput, delay and spectral efficiency.

Universal mobile networks require enhanced capability and appropriate quality of service (QoS) and experience (QoE). To achieve this, Long Term Evolution (LTE) system operators have intensively deployed femtocells (HeNBs) along with macrocells (eNBs) to offer user equipment (UE) with optimal capacity coverage and best quality of service. To achieve the requirement of QoS in the handover stage among macrocells and femtocells we need a seamless cell selection mechanism. Cell selection requirements are considered a difficult task in femtocell-based networks and effective cell selection procedures are essential to reduce the ping-pong phenomenon and to minimize needless handovers. In this study, we propose a seamless cell selection scheme for macrocell-femtocell LTE systems, based on the Q-learning environment. A novel cell selection mechanism is proposed for high-density femtocell network topologies to evaluate the target base station in the handover stage. We used the LTE-Sim simulator to implement and evaluate the cell selection procedures. The simulation results were encouraging: a decrease in the control signaling rate and packet loss ratio were observed and at the same time the system throughput was increased.

A key component in the usage of Industry 4.0 arrangements is the up and coming age of system network, LTE/LTE advanced today, and 5G, later on. Industry 4.0 is conveying private LTE arranges today, as they trust it will give them an upper hand and a solid head start when 5G opens up. LTE uses multiple input multiple output (MIMO), a promising technique to accomplish the necessary data rate. This article presents consequences of 8x8 MIMO framework in fading channel utilizing V-BLAST by means of zero-forcing (ZF) with standard ZF. The relative investigation in the fading channel on account of symbol error proves V-BLAST by means of ZF has predominant execution than standard ZF finder. In addition to this, in order to support adaptive modulation, various M-QAM modulation schemes for these detectors are compared. This comparison shows 128-QAM performs superiorly to staying two. This investigation is carried out to help utilization of MIMO in LTE to support Industry 4.0.

LTE Advanced (LTE-A) technology has been developed by the third generation partnership project in order to facilitate increase in mobile data traffic. In LTE-A network, an efficient resource partitioning scheme is needed to increase the system throughput through the mitigation of Inter Cell Interference (ICI). The objective of this research is to enhance the sum throughput of macrocell through an proposed Region splitting based Resource Partitioning scheme (RRP). In this scheme, the macrocell is partitioned into three regions, namely inner, centre and outer. In a cluster of three cells, the availble frequency spectrum is divided into four non-overlapping parts, out of which three parts of the spectrum are shared by outer and inner region. The remaining part is shared by the centre region. However, the overlaid femtocells partially shares the spectrum of macrocell. The performance of the proposed RRP scheme in terms of sum throughput, sub channel utilization and Jains Fairness index is analysed for both heuristic and optimal region radii approaches. The region radii that result in maximum and optimal sum throughput are analyzed by the proposed RRP scheme. Using Monte Carlo simulations, the radii of both inner and centre region are varied and the region radii that result in optimum sum throughput are configured as the optimal radius. The proposed scheme is compared with the traditional Soft Frequency Reuse scheme with respect to performance metrics. From the result, it is inferred that the sum throughput of macrocell achieves a maximum enhancement of 167.62 and 108.42 % by the proposed scheme of heuristic and optimal region radii approaches respectively.

Long Term Evolution—Advanced (LTE-A) is the most widely used and encouraging technology for 4G and 5G mobile networks. The LTE technology in wireless networks has achieved a significantly high throughput because it makes use of multiple access schemes. We propose an iterative heuristic optimal resource allocation (HORA) algorithm and a chunk based resource block allocation (CRBA) scheduling algorithm to determine resource block (RB) allocation among users to satisfy the quality of service requirement. A heuristic approach which is used in HORA offers a tradeoff between computational complexity and performance. It performs RB and power allocation separately to reduce computational complexity. In the CRBA algorithm sets of RBs are allocated to groups of users keeping power constant to all users. User selection is performed based on channel conditions to improve throughput. RB allocation is an additive method to maximize the data transmission rate and energy efficiency. The use of channel quality indicator feedback from the user equipment (UE) to eNodeB plays an important role in the selection of appropriate modulation and coding schemes and benefits the assigned chunk of RBs to users in the wideband channel-dependent selective frequency-time domain. Here, RB usage and quality-of-service (QoS) constraint are considered for the scheduling algorithm. The HORA algorithm assigns most RBs to users who have high-value signal to noise ratio and continues the RB allocation until it meets the QoS criteria of all users in consideration of the threshold value of the power budget. Problems that arise during continuous resource allocation to the scheduled user are considered as APX-hard and NP-hard problems. An RB and power allocation optimization problem is formulated for the maximum data rate in the cellular network. The simulation results show that the proposed approaches demonstrate considerable throughput improvement at the user end in a significant and robust condition.

Nowadays, fifth generation (5G) wireless network is considered one of the most important research topics in wireless industry and it will be substituting with fourth generation (4G) in several aspects. Although the robustness of orthogonal frequency division multiplexing (OFDM) system against channel delays which is the reason behind using it in LTE/LTE Advanced however, it is suffering from high peak to average power ration (PAPR) and out of band side lobes. So, universal filtered multi-carrier (UFMC) technique is considered a new modulation scheme for 5G wireless communication system to overcome on the common OFDM demits. In contrast, to achieve reliable data transmission in digital communication systems, using error correcting codes are considered an essential over noisy channels. In this paper, BCH code has been used for UFMC system over AWGN. The results showed that using BCH codes in UFMC contributed in enhancing BER performance while could decreasing both of PAPR and OOBE values better than conventional OFDM system.

Intent based networks enable auto-configuration and require low latency access to cloud platforms. The use of cloud platforms incurs high operational costs. Low latency access can be realized by siting data centres close to subscribers. This paper proposes aquaria data centers with low operating costs and latency. In LTE, cloud platforms are normally accessed via the packet network gateway reachable via the serving gateway and mobility management entity. Aquaria data centers are sited close to LTE subscribers and accessed via the mobility management entity. This reduces the size of control packets in the LTE network. Simulations show that the proposed architecture reduces the size of control packets by up to 49.7% and 99.3% when header packets are uncompressed and compressed respectively. The delay associated with receiving configuration information is reduced by 50% on average. The channelcapacity is enhanced by up to 22.8% on average. Keywords: Data centers, LTE-Advanced, Peak Age of Information, Channel Capacity, Header (Control) Packet

This brief deals with self-interference (SI) effects in mobile communication radio frequency (RF) transceivers. The basics of current communication standards, namely Long-Term Evolution (LTE) and 5G, are outlined with a focus on carrier aggregation (CA). RF transceivers that support frequency-division duplex (FDD) and CA variants operate multiple receivers and transmitters simultaneously. We illustrate the resulting SI problems, present suitable models for different SI categories and discuss the associated interference estimation tasks. Moreover, we explain the basic architecture of two common countermeasures: digital and mixed-signal SI cancellation.

Aim: The 5G LTE-Advanced (LTE-A) intended to provide increased peak data rates for the mobile users with the use of Carrier Aggregation (CA) technology. Due to need of uninterrupted bi-directional communication between the eNodeB and User Equipment (UE) in LTEA, Joint Scheduling Algorithm is considered as central research topic. Objective: A modified joint Uplink/ Downlink (UL/DL) Scheduling algorithm to meet on demands service request from the UEs is proposed in this paper. Methods: CA is used for calculate the weight factors for the bandwidth allocation among the mobile users based on the QoS Class Identifier (QCI). However due the huge amount of data flow in the indoor coverage yield introduction of the small cell called femtocells. Femtocells are randomly deployed in macro cell area in order to improve indoor coverage as well capacity enhancement. Result: Mixed types of traffic are considered ranging from real time to non real time flows and quality of service is evaluated in term of throughput, packet loss ratio, fairness index and spectral efficiency. The proposed modified joint user scheduling algorithm results better in delay among the end users due the reduction in the traffic load of the macro cell base station. Conclusion: Simulation results shows that, the proposed methodology suits best for the small scale network architecture with increased spectral efficiency and throughput among the UEs.

Mobility robustness optimization (MRO) is a fundamental issue regarding self-optimization network (SON). In long-term evolution-advanced (LTE-A), handover (HO) optimization in heterogeneous networks (HetNets) is an urgent need to improve system performance. This improvement is in terms of immunity against unnecessary HO (UHO) such as ping-pong HO (PPHO) and against failed HOs in the sense of radio link failure (RLF) such as too-early HO (TEHO) and too-late HO (TLHO), that is, RLF HO. The occurrence of these undesired HOs increases the consumption of network resources and decreases the quality of service (QoS). In this study, we propose a robust algorithm to reduce the number of PPHO, TLHO, and TEHO events to a minimum by an innovative mechanism that adaptively sets the HO control parameters (HCPs). This reduction is obtained without the need for unjustified techniques that assume certain thresholds for the ratio of PPHOs or the ratio of RLF HOs relative to the total number of HOs, as proposed in the most recent literature. We also present the importance of thinking about the existence of a direct relationship between the hysteresis margin (HM) and time-to-trigger (TTT). We invest this relationship in determining adaptive HCPs. Simulation results show that RLF HOs and PPHOs are minimal, almost zero, compared to the literature and the classical method. This study opens a new avenue for research on mobility management. It reorients research axes toward thinking about the possibility of a correlation between HM and TTT. This is what the research community has not yet realized.

Machine-to-Machine (M2M) communication refers to autonomous communication among devices that aims for a massive number of connected devices. M2M communication can support ubiquitous communication and full mechanical automation, and it will change everything from industry to ourselves. Recent developments in communication technology make Long Term Evolution (LTE)/Long Term Evolution-Advance (LTE-A) a promising technology for supporting M2M communication. LTE can support the diverse characteristic of M2M communication due to its IP connectivity, coverage area, and scalability. Therefore, the LTE schedulers should satisfy the need for M2M communication. Motivated by these facts, in this paper, we present a survey on the classification of LTE / LTE-A scheduling methodologies from the perspective of M2M communication. We classify the schedulers based on their objectives, such as energy efficiency, spectrum efficiency, group-based, and Quality-of-Service (QoS) support for Machine Type Communication Devices (MTCDs). We also highlight the scope of future research direction for the scheduling work.

In this paper we consider two accessibility indicators, namely E-RAB (E-UTRAN Radio Access Bearer) and E-RRC (Evolved Radio Resource Control) failure rates, of the LTE-A communication network belonging to one of the regional operators in Russian Federation. The aim of this study is to find the proper algorithms for accessibility indicators prediction, and performance estimation of these algorithms. During the study, we provide temporal dynamics of the indicators and possible failure reasons, behind these indicators. Then the percentage of the time series values is shown, which are corresponding to the abnormal situations (incidents). After that, the stationarity of the inspected time series using augmented Dickey-Fuller (ADFuller), and Kwiatkowski-Phillips-Schmidt-Shin (KPSS) methods is analyzed. Next, the ETS decomposition is performed. In order to predict the future values of the indicators, we utilize SARIMA model, triple Exponential Smoothing (Holt-Winters method), Facebook Prophet, Prony decomposition based model and XGBoost algorithm. Performance estimation is obtained in two ways: by test-sequence- and cross-validation-based Median Absolute Error (MAE). Also, the architecture for the monitoring system, that collects, analyzes and visualizes the required metrics within the infrastructure of the considered operator, is proposed in this paper. Herein, we analyze the possibilities of the open-source solution deployment on each stage of the monitoring process from data mining and preparation up to predictive model learning.

Mobile cellular data networks have allowed users to access the Internet whilst on the move. Many companies use this technology in their products. Examples of this would be Smart Meters in the home and Tesla cars having their “over the air updates”. Both of these two companies use the 4G and 5G technology. So this report will include a technical overview of the technology and\ud protocols (LTE Advanced) used in 4G and 5G networks and how they provide services to the user and how data is transferred within the networks. And there are lots of different parts about the network architecture between the 4G and 5G systems. This report will talk about some different parts between these two systems and some challenges in them.

Nowadays, mobile communication radio frequency transceivers for LTE-A/5G usually operate in frequency-division duplex mode and support carrier aggregation. The resulting complexity requires compromises in the analog front-end. One consequence is a limited stop-band attenuation of the duplex filters that separate the transmit and the receive paths. The resulting transmit leakage signal combined with other non-idealities, like power amplifier (PA) harmonics, can create self-interference problems that desensitize the receivers. In this work, we propose an optimized digital self-interference cancellation scheme to mitigate the unacceptable performance degradation caused by PA induced harmonics. We derive an appropriate interference model and quantify the interference power levels for a specific PA. Based on these results, our low-complex cancellation approach solely targets the dominating components. Our algorithm relies on the auto-covariance matrix for the second and third power of LTE signals, which we derive for the first time in an analytic form. This statistical information can be combined with the transform-domain concept to noticeably improve the performance of a least-mean squares based cancellation algorithm. The capabilities of the approach are demonstrated by means of simulations and are validated on measurement data.

Cellular network deployment with three sectors per site and a frequency reuse factor of one is key to supporting high data rate applications in LTE Advanced Networks. However, such configurations result in increased inter-cell interference. In this paper we model the effects of inter-cell interference on an LTE-Advanced network at two carrier frequencies. We consider two urban environments and four cell ranges. The effects of inter-cell interference are separated into inter-site interference and inter-sector interference. A site-specific 3D ray-tracing tool is used to model the communication channel between the base stations (serving and interfering links) and the user equipment terminals. The inter-site interference is first modelled in terms of its dominant interference proportion and then validated using previously reported field measurements recorded in London (U.K.). Secondly, the inter-site and inter-sector interference components are modelled as a function of user equipment relative position from the serving base stations. Our approach is compatible with the standardized ITU-R model and our proposal can easily be added to these international models. Our model requires no system layout for the interferers and reduces the required channel generation time by a factor of 12 compared with the system layout method.

This paper is about security assaults in LTE/LTE-A Systems. The Long haul Development (LTE)/LTE-Progressed (LTE-An) arrange gives propelled administrations to billions of clients with its higher transfer speeds, better range effectiveness, and lower dormancy than heritage cell systems. Be that as it may, regardless of whether it experiences new security dangers because of its everything IP-based heterogeneous design. Accordingly, there is a basic need to play out a fast and precise system security estimation in LTE/LTE-A system. To accomplish LTE/LTE-A system security estimation, security-applicable information (in short security information) assortment and information examination for assault discovery are required as essentials. Be that as it may, the majority of the current work just spotlights on information assortment and examination for a specific sort of LTE/LTE-An assaults. Little work has been done to exhaustively perform information assortment and examination for identifying different assaults on LTE/LTE-A system. Not quite the same as past work, In this paper we focused on DOS, DDOS Man-in-the-Center (MitM) assaults, rebel base station assaults and the answers for such assaults were broken down to secure LTE and LTE-A systems

Unmanned aerial vehicles (UAVs) enabled networks can enhance wireless connectivity and support emerging services. However, this would require system-level understanding to modify and extend the existing terrestrial network infrastructure. In this study, the authors integrated UAVs as user equipment and base stations into an existing long term evolution (LTE)-Advanced heterogeneous network (HetNet) and provide system-level insights of this three-tier LTE-Advanced air-ground HetNet (AG-HetNet). The performance of AG-HetNet was evaluated through brute-force technique and heuristics algorithms in terms of the fifth percentile spectral efficiency (5pSE) and coverage probability. In particular, system-wide 5pSE and coverage probability were compared, when unmanned aerial base stations (UABSs) are deployed on a fixed hexagonal grid and when their locations are optimised using a genetic algorithm (GA) and elitist harmony search algorithm based on the genetic algorithm (eHSGA); while jointly optimising the inter-cell interference coordination (ICIC) and cell range expansion (CRE) network parameters for different ICIC techniques. The simulation results show that the heuristic algorithms (GA and eHSGA) outperform the brute-force technique and achieve better peak values of coverage probability and 5pSE. Simulation results also show that a trade-off exists between peak values and computation time when using heuristic algorithms. Furthermore, the three-tier hierarchical structuring of reduced power subframes further-enhanced ICIC (FeICIC) defined in 3GPP Rel-11 provides considerably better 5pSE and coverage probability than the 3GPP Rel-10 with almost blank subframes eICIC. They also investigated the network performance for different practical deployment heights of UABS and they found low-altitude UABSs to perform sparsely better than medium-altitude UABSs.

Cellular systems present one of the most suitable wireless technologies to efficiently serve critical machine-type communications (MTC) that require strict quality-of-service (QoS) guarantees. Therefore, ultra-reliable and low-latency communications is a target use case in the design of the upcoming generations of cellular networks. From the radio resource management perspective, guaranteeing such stringent QoS requirements in long term evolution (LTE) networks is a challenging task, especially in the case of the coexistence of MTC with the human-type communications (HTC). In this study, the authors address the resource allocation and scheduling problem of critical MTC that coexist with HTC in LTE. The optimisation problem is formulated such that the overall system utility is maximised while fulfilling the different QoS demands of the two sets of users. Utilising the effective bandwidth and effective capacity theories, a cross-layer design is developed to guarantee the QoS requirements of the critical MTC. For a computationally-efficient solution of the problem, they formulate it as a two-sided matching process that can be used as a practical scheduling scheme. To this end, they analyse the convergence, stability, and computational complexity of the proposed methods. Results reveal the close-to-optimal performance of the matching-based scheduling scheme and its superiority to other existing techniques.

The Heterogeneous Network is widely used in the Fifth Generation wireless network to solve the problem of increasing demand on wireless communication. Femtocell or called Home-evolved NodeB (HeNB) is one of the small cells nominated to be used in this generation. HeNB is a low-power, low-cost, and short coverage area base station randomly assigned by the user. Therefore, HeNB is used in Long Term Evolution (LTE/LTE-Advanced) to support Quality of Service next to conventional cell. Based on the short range and dense use of HeNB, the seamless handover procedure is one of the challenges HeNet system is facing. Though there are numerous present literature work for handover decision issues, this paper attempts to present handover management challenges and the outline of modern handover decision algorithms in between the evolved NodeB (eNB) and HeNB. Furthermore, comprehensive details of the handover procedure in LTE-A Heterogeneous Networks are presented. This survey categorizes the recent studies in decision algorithms for the two-tier network (eNB and HeNB) regarding the main decision technique. Finally, a comprehensive summary of input parameters, techniques, and performance evaluation for each handover decision scheme are discussed by providing the advantage and disadvantage of each category.

LTE D2D communication, which emerges as a SoLoMo network enabler, has become an essential part of our everyday life and brings benefits to subscribers and telecommunication operators alike. Proximate device discovery, or peer discovery, is an essential part in the D2D technology since the node first needs to find its neighbors before initiating D2D communication. With functions of intelligent discovery, context awareness and interactive exchange, D2D communication facilitates content sharing of a device with others. A plethora of works about device discovery have been carried out in ad hoc networks. However, as a new feature in LTE systems, the special characteristics of proximate device discovery raise several unique challenges. In this article, variant aspects of proximate device discovery are surveyed. We first overview the fundamentals of peer discovery, including basic concepts, application scenarios, associated requirements, along with the current standardization progress. The key challenges and open issues in the design of device discovery signals and device discovery protocols for D2D communication in centralized and distributed situations are respectively surveyed. Possible approaches to address these challenges are discussed.

Peak-to-average power ratio (PAPR) is the main parameter affecting the implementation cost of wireless transmitters utilising carrier aggregation in the end-users' channels. In each frequency band, single-carrier frequency division multiple access (SC-FDMA) is exploited as the interface from the transmitter to the receiver, and carrier aggregation is implemented by SC-FDMA on each band. Hence, the power amplifier simultaneously amplifies signals of multiple bands, meaning that its PAPR is affected by the use of multiple SC-FDMA channels. In this study, a novel method has been proposed for the delay and PAPR reduction in carrier aggregation systems. Also, a novel recursive method is proposed to reduce the computational complexity of the proposed partial transmit sequence (PTS) algorithm. Utilising computer simulations, it has been shown that the PAPR can be reduced by 3.5 dB for the time-domain PTS method in mapping for the three-band SC-FDMA comparing to existing methods.

Multi-hop Relay networks are proposed to fulfill the demanding coverage and capacity requirements for current applications in a cost efficient way. It can be used in IMT-Advanced technologies such as 3GPP LTE-Advanced. In this paper, Resource Blocks (RBs) proposed scheduling scheme is considered for zero multi-hop links overflow in Uplink LTE-Advanced. Then based on this scheduling scheme and other network assumptions the Optimum Relay Station (RS) placement in the cell was estimated using nonlinear optimization problem in order to improve LTE-A Uplink performance. The average throughput, Throughput gain, and Mean File Transfer Time (MFTT) are considered as performance measures. The study takes into consideration the impact of Asymmetry between multi-hop links, the effect of different arrival rates from random positions of UEs in the cell. Adaptive MIMO, Modulations, and Coding Switching (AMMCS) scheme is used to maximize network throughput with low bit error rate (BER). Simulation results show effective improvement in uplink network performance using the proposed scheduling scheme and AMMCS with RS at optimum location in the cell.

Long Term Evolution-Advanced (LTE-A) offers several new technologies to improve the performance of the user. However, poor received signal and interference from adjacent cells in the cell-edge area can reduce the efficiency of using individual technology. Therefore, the cell-edge users have lower throughput compared to the other users in the cell and LTE-A standard. An efficient downlink radio resource management scheme is proposed in this paper by combining the coordinated multipoint transmission and reception technique along with carrier aggregation technique to achieve higher throughput for the cell-edge user and better overall performance. The proposed method jointly transmits multiple component carriers to the cell-edge user from different cells to increase the bandwidth, strengthen the received signal, and reduce the interference while it satisfies several constraints. Modified largest weighted delay first packet scheduling algorithm is deployed for resource allocation, which takes into account the delay parameters, the probability of packet loss, and data rates of the user. The obtained system-level simulation results show that the proposed method significantly enhances the throughput performances, spectral efficiency, and fairness index, compared with the existing conventional methods.

SC-FDMA is the most suitable option for the LTE-A uplink. Contiguity plagiarism characteristics are required for optimum channel scheduling in an SC-FDMA system. The right scheduling in the uplink will maximise the user experience and network efficiency. Channel scheduling requires a proper formation of the matrix as an input. The structure of the matrix should be intelligent enough to consider the allocated bandwidth and number of serving users within the range of the active serving cell. In this paper, a weight based resource scheduling (WBRS) algorithm has proposed to improve the network performance in the LTE-A uplink femtocell network. Simulation results show that the WBRS performs better for uplink and eliminates the gap of the current channel scheduling algorithms for the LTE-A femtocell.

Device-to-device (D2D) communication system plays an extremely important role in fulfilling the demands of fourth generation (4G) and fifth generation (5G) technologies. 4G technology cannot meet high data demands. The D2D communication system is believed to provide major improvements in resource usage, energy efficiency, and overall throughput, which are the main demands for the 5G network. Some of the main issues in the D2D communication system involve spectrum efficiency and interference. Although many studies have been conducted on spectrum efficiency improvement and interference reduction, the issues still remain. A study should be conducted to obtain a better understanding of the D2D communication system and to develop a D2D scheme with efficient spectrum utilization and interference reduction. Many survey papers have been published on these issues, but the fundamental concepts behind the D2D communication system require investigation. In this study, we investigated and analyzed the fundamental concepts behind the D2D communication system to develop an efficient D2D resource allocation scheme with reduced interference.

Growing of time-sensitive applications such as streaming multimedia, voice over IP and online gaming required strongly support from mobile communication technology. So, the persistent need for wireless broadband technologies such as LTE-A is essential. LTE-A can achieve QoS in an efficient manner by using a reliable packet scheduling algorithm. It also supports good cell coverage by using heterogeneous capability. In this paper, modifications of proportional fair (PF) algorithm are proposed with different methods to compute the average throughput, which is the main and important parameter in the PF cost function. These methods are geometric mean, root mean square and arithmetic mean. Vienna simulator is used to study the performance of the proposed algorithms. A comparison between PF modifications and the most famous algorithms (the original PF and Best CQI algorithms) with various UE velocities is introduced. Average UE throughput, spectral efficiency, energy per bit, cell throughput and fairness are used as performance indicators. The results expose that QPF has best improved values for spectral efficiency, energy per bit and fairness by 8.4%, 14%, and 9.3%, respectively than original PF. However, Best CQI has a better value of average UE and cell throughput than all algorithms of 2% and 1.8% in low and medium UE velocity, respectively, but the best value of all types of throughput at high speed is gained by QPF. QPF and GMPF has the same performance in fairness with all UEs speeds.

Objectives: This study aims to evaluate the system capacity for mobility management in Long Term Evolution-Advanced (LTE-A) Device to Device (D2D) networks with suitable handover schemes. Methods: This paper introduces power control mechanisms for 5G based on the distance between D2D terminals. Interference is a major issue which reduces the performance of D2D communication. The proposed system introduces an algorithm based on greedy algorithmic approach for interference mitigation with easy handover for system capacity estimation. The implementation is carried out using LabVIEW platform and results are analyzed. Findings: The existing mobile communication approaches transfer calls through base stations irrespective of the distance between the mobile terminals. User mobility is an important factor for D2D communication and proper selection of mobility patterns that helps in increasing the energy efficiency and throughput by reducing interference. Efficient utilization of these mobility patterns are shown in the proposed method for developing an optimal time efficient mobility aware caching mechanism with lower complexity. In the recent works, less importance has been given for users\' contact time duration while they are moving with different speeds. The simulation results show an enhancement in the system capacity of approximately 480 bits/Hz for 50 devices and 290 bits/Hz for 20 D2D users. The simulation results prove that the proposed approach gives better performance than the existing methods. Keywords: D2D; handover; RPGM; LTE-A; SINR

Improved resource allocation scheme for optimizing the performance of cell edge users in Long Term Evolution-Advanced (LTE-A) system is proposed in this paper. The proposed algorithm optimally assigns and allocates Carrier Components (CCs), Radio Blocks (RBs) and Modulation and Coding Scheme (MCS) index for the users based on the Quality of Service (QoS) provision to meet the on demand service requests. The proposed algorithm divides the cell regions into cell centre and cell edge depending on the traffic load on the network. The available RBs are allocated to meet the on demands requests of the users among these two regions. RB usage ratio for optimizing the performance of the scheduling algorithm is used during resource allocation. As the RB usage ratio reaches more than 70%, throughput and data rates of the cell may not be reached in timely and reliable manner. The proposed algorithm takes RB usage ratio into consideration during scheduling to maintain minimum QoS provisions of the users for resource allocation. Simulation result shows that, performance of the cell edge users optimally met with minimum throughput and data rates for reliable communication in the LTE-A system.

According to the identification of the Operating Support System (OSS) by the Smartfren cellular operator in the Central Bandung area, six sites are found to have high traffic capacity with the physical resource block (PRb) percentage of 82.6 %. The use of PRb > 80 % is included in the warning indicator 2 based on the operator’s standards. It is also strengthened by the condition of the existing sites with the average Reference Signal Receive Power (RSRP) of -103.3 dBm, Signal to Interference Noise Ratio (SINR) of 6.28 dB, and throughput of 27.78 Mbps, thus resulting in non-optimal network performance in the area. Therefore, in this study, the inter-band Carrier Aggregation (CA) was applied by combining the 40 Time Division Duplex (TDD) band (2300 MHz) and band 5 Frequency Division Duplex (FDD) (850 MHz). One of the advantages of applying this method is that it can increase the user network capacity by maximizing the resources owned by the operator. The predetermined scenario taking into account the initial network condition indicated a decrease in the PRb percentage by 44.50 % and an increase in the average RSRP value by 12.8 dBm, SINR by 5.14 dB, and throughput by 34.59 Mbps.

Increasing the user downlink throughput is always a task of utmost importance for any cellular network service provider. However, most of the research is only focused on system simulations due to environmental simplicity. In this paper, instead of focusing on theoretical simulations, we aim to find the best practical solution to increase user throughput in an actual HetNet deployment where many small cells are deployed inside a building. An inter-frequency deployment is implemented in the actual LTE-A HetNet environment. A series of data collections were conducted in an actual indoor LTE-Advanced HetNet (heterogeneous network) environment with optimization strategies such as ABS (Almost Blank Subframe) and turning off/on interfering antennas. Detailed findings and analysis are provided to better understand the complicated actual HetNet environment. This work is also important to understand the future 5G network since the small cells and HetNet will continue to play an important role in the 5G network.

This article presents a comprehensive survey of the literature on self-interference (SI) in long-term evolution advanced (LTE-A) and fifth-generation (5G) new radio transceivers and should serve the reader as a guide and starting point for further work on SI management. Current trends in cellular transceiver designs are discussed, and reasons why new technologies, such as carrier aggregation, cause potential sensitivity degradation due to self-interfering signals are highlighted. The survey provides an overview of the most common interference mechanisms and continues with a taxonomy on SI mitigation architectures by comparing the strengths and weaknesses of various techniques.

To support the rising number of user equipments (UEs), LTE-A allows some UEs directly talking with each other to facilitate spectrum reuse, which is known as device-to-device (D2D) communication . Since D2D UEs (DUEs) consume resources and bring out interference, how to allocate resources and power is important. Existing studies seek to make more DUEs reuse resources of cellular UEs (CUEs, which are the UEs talking with the eNB) to increase throughput. However, it is inefficient for some CUEs (e.g., those near cell edge) to share resources with others due to high interference. Thus, a new sharing paradigm, called the pure D2D model , is proposed to allow DUEs sharing resources without involving CUEs for flexibility. This new model is helpful to IoT (Internet of Things) applications, where the overwhelming majority of devices are usually DUEs. The paper defines an optimization problem to maximize links supported in the network, and proposes a D2D resource allocation and power control (DRAPC) framework. By vertex coloring, DRAPC gives a preliminary grouping of UEs for resource allocation. Then, each group is carefully reformed by exchanging members and adding new ones, so as to increase signal quality and degree of resource sharing. Simulation results show that DRAPC not only improves network performance but also guarantees fairness among links.

The purpose of LTE-A technology is to provide high spectral efficiency, lower delay and stronger intercell interference control for a multi- user environment. The architecture of LTE basically contains E-UTRAN and evolved packet core. E-UTRAN is the combination of UE and ENodeB (enhanced node B) used to control the radio network. EPC provide end to end connection and backward capability with previous networks. Major entities included in EPC are P-GW, S-GW, HSS and MME. This new architecture fulfil the requirement of next-generation mobile networks for high connectivity and multiple type of networks. Heterogeneous network is one of them in which different power base stations like femtocell, picocell, and radio remote head deployed in a geographical area with in macrocell cell. It is one of the cost effective solution to provide high throughput and spectral efficiency and fairness for cell edge user. Deployment of femtocell improved the data rate and coverage in small regions like office, home, shopping mall and dense areas. Along with this an efficient fair sharing of resource allocation plays an important role in improving the performance of networks. This paper analysed the performance of round robin, resource fair, Max-throughput, best CQI and proportional fair LTE-A resource scheduling techniques on homogeneous networks. For heterogeneous networks a new cluster based proportional fair resource scheduling technique is proposed, which provides an efficient resource to the most sufferer user and improved fairness and cell edge user throughputs. In heterogeneous networks multiple femto cell were deployed in macro cell area. Access policies are applied on open and closed group. The performance is measured in terms of cell edge throughputs, peak throughputs, average throughputs, wideband SINR, spectral efficiency, and fairness index for homogeneous, heterogeneous networks and for user mobility. The performance result showed that Best CQI and MaxTP scheduler outperforms in throughput level and attains highest average cell throughput of 83 Mbps and UE average throughput of 20 mbps in homogeneous networks and approximately 43 Mbps in heterogeneous networks. Comparative result in heterogeneous network indicates that the proposed scheduler increases 2% gain in fairness and 1–1.89% gains in edge throughputs with respect to proportional fair scheduler and allocates 79% fair share resources among UE. Round robin scheduler delivered very poor throughput and fairness index in both homogeneous and heterogeneousnetworks.