Term Evolution Networks Research Articles

Converging Towards Open Radio Access Networks – A Comprehensive Review

Radio Access Networks (RAN) have been an integral part of the cellular mobile communication systems since the deployment of Global System for Mobile Communication (GSM) networks and later for the legacy Universal Mobile Telecommunication Systems (UMTS) and Long Term Evolution (LTE) networks. However, due to increasing demands of the users, throughput, ultra-lower latency, virtualization of the network and to cater the seamless connectivity of millions of wireless devices with the cellular networks, the advent of RAN needs to be brought under consideration. In this paper the traditional RANs are discussed with the necessity for their transition into the Open RAN (ORAN), considering all its essential parameters. The constraints of the legacy RAN architectures are explored with an overview of the RAN intelligent controllers, ORAN and its types. This paper additionally examines the function of artificial intelligence in Common Public Radio Interface (CPRI), enhanched CPRI, and xApps in terms of use cases along with the challenges associated with their deployment. The paper also present challenges and future of ORAN.

DRX Mechanism for Machine Type Communication (MTC) in Long Term Evolution Network (LTE): Potentials and challenges

Discontinuous Reception (DRX) Mechanism is the power saving technique employed by the Long Time Evolutional (LTE) Network to reduce the power saving. The scheme has seen numerous improvements and tuning to enhance its performance. The Machine Type Communication (MTC) devices have characters that widely differ from the normal devices (Human Type Devices). Therefore, DRX schemes needs to be adjusted to fully accommodate MTC. In this work, a survey of MTC DRX scheme literatures is adapted depicting challenges and potential.

A quality of experience model for live video in first-person-view drone control in cellular networks

Several upcoming 5G and 6G services will rely on unmanned aerial vehicles (UAV) sending live information to remote terminals. Thus, understanding the traffic flows that might influence end-user experience in these services is key for cellular network operators. One of these UAV-based services is first person view (FPV) drone control, consisting on the remote control of the UAV in Beyond Visual Line of Sight scenarios using only the live video visualized in a ground control station. This work focuses on the networking aspects of this service by presenting the assembly, integration and evaluation methodology of an UAV quadrotor teleoperated via FPV through a Long Term Evolution (LTE) network or WiFi radio access link. To assess system performance, three different connectivity schemes between UAV and ground control station are tested, namely server-based connection via LTE, direct LTE, and peer-to-peer WiFi connection. Then, several experiments are carried out in the testbed to characterize telemetry, control and video traffic for FPV service in the above schemes. Later, a methodology is defined to estimate Quality of Experience (QoE) for FPV service based on image quality and video latency measurements collected at network and application level. Results show that the QoE model for live video introduced in this work can be the basis of more sophisticated models for cellular FPV services.

Performability analysis of multi-service call admission control schemes in LTE networks

Two important Quality-of-Service (QoS) measures for cellular networks are the fractions of New Calls (NCs) and Handoff Calls (HCs). These types of calls are usually blocked or dropped for two reasons: radio channels are occupied (performance reason) or failure of radio channels (availability reason). Call Admission Control (CAC) is a technique that accepts or rejects user requests in a network. This paper proposes two new CAC schemes for Long Term Evolution (LTE) networks supporting two classes of services (Real-Time (RT) and Non-Real-Time (NRT)). The proposed CAC schemes are composites, meaning that they consider performance changes associated with the failure and recovery of radio channels. We use the Probabilistic Model Checking (PMC) to perform a comparative analysis between the performability measures (combination of performance and availability measures) of the proposed composite CAC schemes and an existing pure performance model. First, we model the composite CAC schemes with multidimensional Continuous Time Markov Chain (CTMC). Then, we specify QoS requirements through the CTMC using the Continuous-time Stochastic Logic (CSL). Finally, we quantify the performability measures of the composite CAC schemes by checking CSL steady-state, transient, and path formulas using the PRISM model checker.

A comprehensive analysis of the coverage and performance of 4G and 5G deployments

5G New Radio (5G NR), has now been deployed in all available bands: low (<1 GHz), mid (1–6 GHz), and high (>24 GHz), each with a trade-off between coverage and throughput/latency performance. The preceding 4G Long Term Evolution (4G LTE) networks also catching up to 5G mid-band by deploying in the unlicensed 5 GHz (using License Assisted Access/LAA) and the 3.5 GHz Citizens Broadband Radio Service (CBRS). We present a comprehensive analysis of 4G and 5G deployments in Chicago and Miami, focusing on coverage, throughput, and latency performance in low-, mid-, and high-bands, under several scenarios: outdoor, outdoor-to-indoor, and under high temperature. To measure deployed networks, we utilized a scalable methodology with commercial and custom apps to collect detailed signal data (e.g., signal strength, cell ID, throughput) on user device (i.e., smartphones). The analysis based on our measurements yields the following findings: (i) when comparing the throughput and latency performance of optimized mid-band 4G networks to 5G (both standalone (SA) and non-standalone (NSA)), they exhibit comparable performance, and (ii) it is important to note that mmWave 5G has the capability to deliver multi-Gbps throughput, even in NSA mode. However, this high-speed performance is susceptible to limitations imposed by factors such as distance, body interference, obstructions (such as Low-e glass), and overheating, which can render its performance less reliable. Therefore, even though 5G exhibits considerable potential in its early stages, additional efforts are required to guarantee that the stated goals of 5G are met.

Evaluating the level of inteference in UMTS/LTE heterogeneous network system

&lt;p&gt;The study evaluated interference in a dense heterogeneous network using third-generation universal mobile telecommunication systems (UMTS) and fourth-generation long term evolution (LTE) networks LTE. The UMTs/LTE heterogeneous network determines the level of interference when the two communication systems coexist and how to improve the network by migrating from UMTs to LTE, which has a faster download speed and larger capacity. Techno lite 8 on third generation (3G) and Infinix Pro 6 on fourth generation (4G) were used to measure network the received signal strength (RSS) during site investigation. UE interference was detected and traced using a spectrum analyzer. UMTS and LTE path loss exponents are 2.6 and 3.2. Shannon's capacity theorem calculated LTE and UMTS capacity. When signal to interference and noise ratio (SINR) was used as a quality of service (QoS) indicator, MATLAB channel capacity plots did not match Shannon's due to neighboring interference. UMTS had an R2 of 0.54 and LTE 0.57 for the Shannon channel capacity equation. Adjacent channel interference (ACI) user devices reduce network capacity, lowering QoS for other customers.&lt;/p&gt;

Predictive Modeling of Delay in an LTE Network by Optimizing the Number of Predictors Using Dimensionality Reduction Techniques

Delay in data transmission is one of the key performance indicators (KPIs) of a network. The planning and design value of delay in network management is of crucial importance for the optimal allocation of network resources and their performance focuses. To create optimal solutions, predictive models, which are currently most often based on machine learning (ML), are used. This paper aims to investigate the training, testing and selection of the best predictive delay model for a VoIP service in a Long Term Evolution (LTE) network using three ML techniques: Multilayer Perceptron (MLP), Support Vector Machines (SVM) and k-Nearest Neighbors (k-NN). The space of model input variables is optimized by dimensionality reduction techniques: RReliefF algorithm, Backward selection via the recursive feature elimination algorithm and the Pareto 80/20 rule. A three-segment road in the geo-space between the cities of Banja Luka (BL) and Doboj (Db) in the Republic of Srpska (RS), Bosnia and Herzegovina (BiH), covered by the cellular network (LTE) of the M:tel BL operator was chosen for the case study. The results show that the k-NN model has been selected as the best solution in all three optimization approaches. For the RReliefF optimization algorithm, the best model has six inputs and the minimum relative error (RE) RE = 0.109. For the Backward selection via the recursive feature elimination algorithm, the best model has four inputs and RE = 0.041. Finally, for the Pareto 80/20 rule, the best model has 11 inputs and RE = 0.049. The comparative analysis of the results concludes that, according to observed criteria for the selection of the final model, the best solution is an approach to optimizing the number of predictors based on the Backward selection via the recursive feature elimination algorithm.

COST ANALYSIS OF DEPLOYING FEMTOCELLS IN SPEED TRAINS IN NIGERIA TO IMPROVE INDOOR COVERAGE AND CAPACITY OF LTE NETWORK

The cost analysis of deployment of femtocells in speed trains along Abuja-Kaduna standard gauge railway line to improve the coverage and capacity of Long Term Evolution (LTE) network for 5000 commuters using that route daily is presented in this paper. Additional cost will include the cost of femtocells procurement, license, installation, backhaul, operation &amp; maintenance. The cost analysis is carried out using techno-economic model to determine the business viability of embarking on such a project by LTE network providers in Nigeria. The estimated capital expenditure (CAPEX) and operating expenditure (OPEX) as well as the projected revenues accrues from this project form the cash outflows and cash inflows used to simulate the net present value (NPV) and internal rate of return (IRR) in MS Excel environment on a discount rate and tax rate of 22% and 30% respectively to determine the feasibility of the investment. The results of their NPV values which are positive show that the macro-femtocell arrangement in speed train plying AbujaKaduna railway route is cost effective for a life time of 10 years and is feasible up to an IRR 40% which exceeds the estimated discount rate of 22%. The value of the payback period indicates that it will not take long for any LTE network provider in Nigeria to recover their investment. The result of the NPV sensitivity analysis shows how various cost and non-cost parameters affect the costeffectiveness of such investment.

An overview of LTE/LTE‐A heterogeneous networks for 5G and beyond

AbstractThe potential of fifth‐generation (5G) and beyond wireless connectivity is to deliver higher data rates, much lower latency, more frequent increase in channel capacity, and significant improvements in Quality of Service (QoS), compared to the current Long Term Evolution (LTE) networks. The continued growth of smart devices, the introduction of trending multimedia applications, and the dramatic increase in demand and use of wireless data communication are already causing a significant load on current mobile networks. 5G wireless networks, with enhanced user data rates, delays, capacity and QoS, are anticipated to solve many of the existing problems of mobile networks. In this study, we review the emergent wireless LTE‐A and 5G networks to provide an overview of the challenges and the solutions suggested in recent literature towards forthcoming 6G networks. We first discuss the new structural changes associated with the Radio Access Network (RAN) design, heterogeneous network and LTE or LTE‐Advanced (LTE‐A) network. To understand the challenges and research gaps in 5G and beyond networks, the paper reviews the outstanding features of the new QoS and Self‐Organization Networks (SON) related to the emerging 5G networks. Data rates, bandwidth and coverage have been given significance throughout this review because these are some major challenges towards 6G networks. Since understanding the present state of 5G usage is critical to its adoption, the paper also discusses related field tests, trials, and simulation tests. Finally, we identify existing major research problems and outline potential research areas.

Empirical Path Loss Modelling for Selected LTE Networks in FUTA Campus, Ondo State, Nigeria

Deployed Long Term Evolution (LTE) networks in Nigeria can barely meet the desired 100 Mbps downlink throughput leading to unsatisfactory quality of experience by mobile users. Typically, mobile network operators (MNOs) rely on network planning tools designed for generalized environments. These tools employ legacy propagation models that may not be suited to the operational environments under consideration. As such, the efficiency of such legacy path loss models suffers when they are used in environments different from those for which they have been designed, and this poses a major challenge to the MNOs. This is because the Nigerian geographical areas and topographical features vary widely from the areas where the legacy models were developed. Several studies in Nigeria and other African countries have shown that the legacy path loss models perform unsatisfactorily when compared with field measurement data. To address this challenge and enable accurate path loss prediction for an urban campus environment, extensive measurements at 2600 MHz were carried out in the main campus of the Federal University of Technology Akure (FUTA), Ondo State, Nigeria. The measurement results were compared with the path loss predictions from the commonly-used legacy propagation models (Free space and 3GPP TR 36.873). The results show that the legacy path loss models under-predict the path loss averagely by 20-40 dB, and up to 88 dB in some cases, for the considered environment. Root mean square error (RMSE) values in the range of 1.895 and 9.159 were also observed along the routes. The measurement results will enable the MNOs to adjust the path losses in order to deliver improved quality of service.

A Hybrid Approach for Optimized Resource Allocation in a Deployed 4G Long Term Evolution (LTE) Network

A Hybrid Approach for Optimized Resource Allocation in a Deployed 4G Long Term Evolution (LTE) Network

Modified Multipath Transmission Control Protocol Using Logarithmic Increase Under Long-Term Evolution and Wi-Fi Networks

Multipath transmission control protocol (MPTCP) has been proposed for devices with multiple network interfaces. This idea seems to be impossible for user implementation at the beginning of its proposal. However, the emergence of smartphones with multiple network access allows this idea to be implemented. This paper provides both theoretical and empirical throughput analysis of MPTCP under long term evolution (LTE) and Wi-Fi networks. First, a new modified congestion control is presented as an enhancement of standard TCP Reno using logarithmic function. Second, the existing MPTCP approaches like linked increase algorithm (LIA) and balanced LIA (BALIA) are discussed briefly. Finally, the experimental results under long term evolution (LTE) and Wi-Fi under software defined wireless networking (SDWN) are given along with the analysis. The experimental result shows that the proposed congestion control achieves higher average congestion window size. The BALIA MPTCP is shown to have higher throughput than that of the LIA MPTCP.

Scalable priority-based resource allocation scheme for M2M communication in LTE/LTE-A network

Machine-to-Machine (M2M) communication in the Long Term Evolution (LTE) network has recently grown exponentially as the volume of connected devices has increased rapidly in the last decade. M2M traffic can be understood via certain parameters in terms of packet length, packet generation frequency, delay, and data rate requirements, and it typically flows in the uplink direction. Primarily, the LTE network design is optimized for Human-to-Human (H2H) communication. As a result, designing uplink scheduling in LTE networks is fraught with difficulties which restrict the use of potential capacity. In response to the preceding methodologies, focusing on the QCI priority degrades resource utilization and cell throughput. Therefore, a scheduling mechanism needs to optimize the system performance with priority support to use LTE in M2M communication. This paper highlights existing flaws in the optimization process and proposes a scalable priority-based resource allocation scheme for M2M communication in the LTE/LTE-Advance network. The proposed scheme for resource allocation strikes a balance between resource utilization and application priority support. According to the results, the proposed scheduling algorithm outperforms the standard algorithms concerning resource sharing fairness, average resource utilization, QCI priority support, and delay budget violation.

An intelligent energy efficient handover mechanism with adaptive discontinuous reception in next generation telecommunication networks

Long Term Evolution (LTE) and LTE-Advanced (A) networks have been introduced to accommodate the User Equipment (UEs) that supports high complex technologies such as OFDM, SC-FDMA, MIMO. Recently, 3GPP presented 5G technology to meet the performance requirement of the International Mobile Telecommunication (IMT)-2020. It supports three specific services like Enhanced Mobile Broadband (eMBB), Ultra-Reliable Low Latency Communication (URLLC), massive Machine Type Communication (mMTC). To increase the capacity of the network, 5G will deploy an ultra-dense network in the metro area. It fulfils the spectral efficiency requirement but at the same time increases handover rate. Due to handover, the power consumption of UEs may increase dramatically. To overcome this issue, LTE-A network adopts Discontinuous Reception (DRX) to conserve battery life of UE. 5G networks will also apply evolved variations of this scheme. In general, DRX is composed of some parameters and these need to be optimized during mobility. This paper presents a method for preservation of the battery life of UEs during mobility. The proposed mechanism comprises of three parts. In the first part, Part 1, the operation of normal DRX during mobility is explored. The next parts, Part 2 and Part 3, utilize the machine learning-based methods for the pre-prediction of Target eNB (TeNB) and provide ranks to the UEs during handover. Further, DRX parameters are adjusted according to the dynamic behaviour of the network. Handover latency, end-to-end delay is improved by 20% and 55%, respectively as compared to the conventional scheme. Further, machine learning based (Part 2) and dynamic adjustment of DRX parameters (Part 3) contribute to enhance the power saving factor by maximum up to 85%, and 33% as compared to state of art mechanism.

FedRec: Trusted rank-based recommender scheme for service provisioning in federated cloud environment

The emergence of on-demand service provisioning by Federated Cloud Providers (FCPs) to Cloud Users (CU) has fuelled significant innovations in cloud provisioning models. Owing to the massive traffic, massive CU resource requests are sent to FCPs, and appropriate service recommendations are sent by FCPs. Currently, the Fourth-Generation (4G)-Long Term Evolution (LTE) network faces bottlenecks that affect end-user throughput and latency. Moreover, the data is exchanged among heterogeneous stakeholders, and thus trust is a prime concern. To address these limitations, the paper proposes a Blockchain (BC)-leveraged rank-based recommender scheme, FedRec, to expedite secure and trusted Cloud Service Provisioning (CSP) to the CU through the FCP at the backdrop of base 5G communication service. The scheme operates in three phases. In the first phase, a BC-integrated request-response broker model is formulated between the CU, Cloud Brokers (BR), and the FCP, where a CU service request is forwarded through the BR to different FCPs. For service requests, Anything-as-a-Service (XaaS) is supported by 5G-enhanced Mobile Broadband (eMBB) service. In the next phase, a weighted matching recommender model is proposed at the FCP sites based on a novel Ranking-Based Recommender (RBR) model based on the CU requests. In the final phase, based on the matching recommendations between the CU and the FCP, Smart Contracts (SC) are executed, and resource provisioning data is stored in the Interplanetary File Systems (IPFS) that expedite the block validations. The proposed scheme FedRec is compared in terms of SC evaluation and formal verification. In simulation, FedRec achieves a reduction of 27.55% in chain storage and a transaction throughput of 43.5074 Mbps at 150 blocks. For the IPFS, we have achieved a bandwidth improvement of 17.91%. In the RBR models, the maximum obtained hit ratio is 0.9314 ​at 200 million CU requests, showing an improvement of 1.2% in average servicing latency over non-RBR models and a maximization trade-off of QoE index of 2.7688 at the flow request 1.088 and at granted service price of USD 1.559 million to FCP for provided services. The obtained results indicate the viability of the proposed scheme against traditional approaches.

Implementation of a Malicious Traffic Filter Using Snort and Wireshark as a Proof of Concept to Enhance Mobile Network Security

In the 1970s, roaming interconnections for cellular networks were designed for a few trusted parties. Hence, security was not a major concern. Today, the SS7 (Signaling System no. 7) solution that is several decades old is still used for many roaming interconnections. SS7 has been proven vulnerable to serious threats due to deregulation, expansion, and convergence with IP-based Long Term Evolution (LTE) networks. The limitations of the SS7 network that it is unable to check the subscriber’s authentic location, verify their identity and filter illegitimate messages, makes the system vulnerable to attacks. Adversaries taking advantage of these shortcomings can inflict threats such as interception of calls and text messages, subscriber tracking and denial of service attacks. Although LTE and Diameter signaling protocols promise enhanced security keeping up with the latest attack vectors, their inherent flaws related to roaming interconnections are still there and continue to make the networks vulnerable. Hence, a highly secure signaling network is required to protect the operators and the subscribers from a diverse range of security attacks. SS7 network protocol layers, such as signaling connection control part (SCCP), transaction capabilities application part (TCAP), and global system for mobile Communications – mobile application part (GSM MAP), manage connectivity between networks and subscribers. An analysis of the parameters of these layers may provide a clear insight into any anomalies present. Unfortunately, these parameters are not validated and verified at the network’s edge. The major contribution of this research is a methodology for detecting anomalies by checking malformed parameters and intra-layer parameter discrepancies at the abovementioned protocol layers. This paper provides an insight into the severity of SS7 network security vulnerabilities. Furthermore, it provides a proof of concept for the analysis of SS7 network traffic using the Wireshark packet capture tool and the Snort intrusion detection system (IDS) capable of detecting malicious traffic patterns.

Experimental Assessment of New Generation Radio Networks Based on Layered Division Multiplexing

Despite the recent advances in broadband penetration and accessibility, broadcasting networks continue to be the most efficient way for delivering media content to large areas independently of the user density. Nevertheless, a convergence of broadcasting services into the broadband networks is foreseen. In this context, Layered Division Multiplexing (LDM) allows the joint provision of unicast, multicast, and broadcast services in mobile cells infrastructure. Despite the success of LDM in broadcasting infrastructure, its practical application in Long Term Evolution networks providing Evolved Multimedia Broadcast Multicast Services (LTE eMBMS) and 5G-MBMS is more difficult. In this paper, we experimentally quantify the cell-interference and its impact on the network performance and Quality of Service. Our experiments reveal that the inter-cell interference margin for LTE eMBMS is about 3 dB higher compared to traditional LTE networks. If a layered architecture is incorporated this higher inter-cell interference would cause a reduction of approximately 19% of the Enhanced Layer (Lower Layer) coverage.

Performance Comparison between Handover Decision Algorithms for Horizontal Handover in Long Term Evolution Networks

Comparative Analyses of Handover Decision Algorithms (HODA) for horizontal handovers in Long Term Evolution Network (LTE-A) in terms of Key Performance Indicators (KPIs) were conducted using system level simulation in MATLAB. The KPIs analyzed were the users’ throughput, spectral efficiency, cell –edge Spectral efficiency, handover success rate , call drop Rate, Cumulative Distribution Function (CDF) of Received Signal Reference Power (RSRP), Average RSRP over Primary Component Carrier (PCC) and Secondary Carrier (SCC) and interruption time. . From the results obtained, the algorithm based on spectrum aggregation of carriers from wireless communication spectrum and television white space band referred to as the proposed-TVWS algorithm showed remarkable performance improvements in all the chosen KPIs when compared with MIF and CONV except in handover success rate at UEs speeds less than 70 km/hr of which MIF-HODA algorithm seemed to perform better. Therefore, the proposed-TVWS has yielded baseline certainty in the increase of wireless network quality of service in addition to the seamless network connectivity for the mobile users.

Multi-User MIMO & Beam Forming with Carrier Aggregation for LTE- Advanced System

Recently, Long Term Evolution Networks is a very popular cellular communication network that provides a very high speed of download and upload data in various environments. Resource allocation using different techniques is the emerging research area in the field of LTE and LTE-Advanced networks. In this paper, we analyze the performance of the LTE advanced carrier aggregation scheduling with multi-users MIMO and Beamforming techniques. Further, carrier aggregation scheduling with multi-users MIMO and Beamforming schedule compared with the round-robin (RR), FFR, and BCQI scheduling techniques. The performance of carrier aggregation with the multi-user MIMO and Beamforming techniques significantly increased overall system throughputs and show gain in terms of spectral efficiency, user throughput, user cell edge throughput, and fairness index.

Toward a Live BBU Container Migration in Wireless Networks

Cloud Radio Access Networks (Cloud-RANs) have recently emerged as a promising architecture to meet the increasing demands and expectations of future wireless networks. Such an architecture can enable dynamic and flexible network operations to address significant challenges, such as higher mobile traffic volumes and increasing network operation costs. However, the implementation of compute-intensive signal processing Network Functions (NFs) on the General Purpose Processors (General Purpose Processor) that are typically found in data centers could lead to performance complications, such as in the case of overloaded servers. There is therefore a need for methods that ensure the availability and continuity of critical wireless network functionality in such circumstances. Motivated by the goal of providing highly available and fault-tolerant functionality in Cloud-RAN-based networks, this paper proposes the design, specification, and implementation of live migration of containerized Baseband Units (BBUs) in two wireless network settings, namely Long Range Wide Area Network (LoRaWAN) and Long Term Evolution (LTE) networks. Driven by the requirements and critical challenges of live migration, the approach shows that in the case of LoRaWAN networks, the migration of BBUs is currently possible with relatively low downtimes to support network continuity. The analysis and comparison of the performance of functional splits and cell configurations in both networks were performed in terms of fronthaul throughput requirements. The results obtained from such an analysis can be used by both service providers and network operators in the deployment and optimization of Cloud-RANs services, in order to ensure network reliability and continuity in cloud environments.