UMTS Terrestrial Radio Access Network Research Articles

LTE channel throughput assessment and comparison under different terrain

SummaryIn evolved UMTS terrestrial radio access network, long‐term evolution is known as the fourth‐generation mobile network with a leading radio performance metric as a throughput and signal‐to‐noise ratio (SNR) that affect the radio links. In this paper, we analytically describe the different long‐term evolution propagation model and measure and compare the throughput and SNR on different Doppler frequencies. To validate the performance of channel, we implement network on 3 standard models, viz, as pedestrian (EPA), vehicular (EVA), and typical urban (ETU) at different Doppler frequency (5, 70, 300, and 750 Hz), and different value of SNR (10, 13, 16, and 19 dB) on downlink channel and measured the channel throughput rate. We conclude that a performance of the channel for high SNR values severely affected by the high value of the Doppler frequency while for the channels at low SNR values is a negligible effect with high Doppler frequency.

Comparative performance analysis of different resource scheduler and characterising the impact of proportional fair under different TTI feedback delay in EUTRA network

Evolved UMTS terrestrial radio access network (EUTRAN) offers high uplink and downlink throughput. In this paper, we investigate the performance of five different schedulers of media access control for resource allocation, such as round robin (RB), proportional fair (PF), best channel quality indicator (CQI), max transmission point (TP) and resource fair (RF). On comparing the performance of resource allocation schedulers in the indistinguishable arrangement, we found the proportional fair (PF) offers balance in terms of individual metrics. Furthermore, we analyse the effect of feedback transmission time interval (TTI) delay on two typical EUTRAN networks referred to as long term evolution (LTE) and LTE-Advance (LTE-A). We evaluate the performance of the PF scheduler for both networks under varying feedback delay in TTI. Simulated results show that the delay in TTI affects the performance of resource allocation. Feedback delay improves network performance by compensating effect of imperfect channel.

Comparative performance analysis of different resource scheduler and characterising the impact of proportional fair under different TTI feedback delay in EUTRA network

Evolved UMTS terrestrial radio access network (EUTRAN) offers high uplink and downlink throughput. In this paper, we investigate the performance of five different schedulers of media access control for resource allocation, such as round robin (RB), proportional fair (PF), best channel quality indicator (CQI), max transmission point (TP) and resource fair (RF). On comparing the performance of resource allocation schedulers in the indistinguishable arrangement, we found the proportional fair (PF) offers balance in terms of individual metrics. Furthermore, we analyse the effect of feedback transmission time interval (TTI) delay on two typical EUTRAN networks referred to as long term evolution (LTE) and LTE-Advance (LTE-A). We evaluate the performance of the PF scheduler for both networks under varying feedback delay in TTI. Simulated results show that the delay in TTI affects the performance of resource allocation. Feedback delay improves network performance by compensating effect of imperfect channel.

Radio Resource Management in Heterogeneous Networks, Functional Models and Implementation Requirements

The scope of this paper is to provide a detailed description of the selected architecture and the functionalities considered for the AROMA project. This project focuses on a heterogeneous radio access network which includes several Radio Access Technologies (RAT) , namely; UMTS Terrestrial Radio Access Network (UTRAN), GSM/EDGE Radio Access Network (GERAN), and Wireless Local Area Network (WLAN). The corresponding Common Core Network (CN) is considered to provide and satisfy different kind of services, thus, different identified services have different QoS, then, so the goal is to study and analyze some algorithms, that best fit in the network in order to enable quality of service (QoS) based on the service demand in the network. Radio Resource Management (RRM) refers to a group of algorithms that are collectively responsible for efficiently utilizing the radio resources within a RAT to provide services with an acceptable level of QoS. Mainly, at present, Radio Resource Management (RRM) algorithms are implemented independently in each RAT. In the meanwhile, The Common RRM (CRRM) strategy, has been proposed in the literature to coordinate radio resources utilization among a number of RATs in an optimized way. This paper analyze CRRM solutions with particular attention on implementations. Starting from an analysis of the state of the art, the most interesting solutions have been critically analyzed and then some in depth investigations on some of the identified solutions have been performed.

Fast Recovery Approach to Improve TCP Congestion Problem in 4G LTE Network Using NS-3

The Long Term Evolution (LTE) of the UMTS Terrestrial Radio Access and Radio Access Network is another correspondence standard went for business arrangement in 2010. Objectives for LTE incorporate backing for enhanced framework limit and scope, high top information rates, low idleness, lessened working expenses, multi- recieving wire support, adaptable transfer speed operations and consistent mix with existing systems. The point of this proposal is to study the effects on the end-client and framework execution when clients with high bit rates TCP administrations are traveling through the system. These effects influence the decreased endclient or framework throughput, e.g., because of clogging in the vehicle system, prompting poor usage of the vehicle and radio assets accessible. To reach such a point, it has been important (1) to make another test system with the ns-3 and perform reenactment in diverse system settings and (2) define a quick recuperation approach ready to catch the essential flow of the genuine framework and to keep away from blockage circumstance. Conceivable answers for relieve the effects are researched by contrasting the recreations consequences of TCP execution in the radio and transport system and we perform Fast recovery in TCP Stream.

Intelligent Hybrid Cheapest Cost and Mobility Optimization RAT Selection Approaches for Heterogeneous Wireless Networks

The evolution of wireless networks has led to the deployment of different Radio Access Technologies (RATs) such as UMTS Terrestrial Radio Access Network (UTRAN), Long Term Evolution (LTE), Wireless Local Area Network (WLAN) and Mobile Worldwide Interoperability for Microwave Access (WiMAX) which are integrated through a common platform. Common Radio Resource Management (CRRM) was proposed to manage radio resource utilization in heterogeneous wireless networks and to provide the required Quality of Service (QoS) for allocated calls. RAT selection algorithms are an integral part of the CRRM algorithms. Their role is to decide, when a new or Vertical Handover (VHO) call is requested, which of the available RATs is most suitable to fit the need of the incoming call and when to admit them. This paper extends our earlier work on the proposed intelligent mobility optimization and proposes an intelligent hybrid cheapest cost RAT selection approach which aims to increase users’ satisfaction by allocation users that are looking for cheapest cost connections to a RAT that offers the cheapest cost of service. A comparison for the performance of centralized load-balancing, proposed and distributed cheapest cost and mobility optimization algorithms is presented. Simulation results show that the proposed intelligent algorithms perform better than the centralized load-balancing and the distributed algorithms.

Multiple-Access Technology of Choice In 3GPP LTE

Third-Generation Partnership Project (3GPP) standardizes an Evolved UMTS Terrestrial Radio Access Network (E-UTRAN) as air interface in its release 8 LTE. Orthogonal Frequency Division Multiple Access ( OFDMA) and Single Carrier-Frequency Division Multiple Access(SC-FDMA)are key technologies for the air interface of mobile broadband systems.It is evident that mobile broadband access technologies are reaching a commonality in the air interface and networking architecture; they are being converged to an IP-based network architecture with OFDMA based air interface technology. The air interface of E-UTRAN is based on OFDMA in downlink and SC-FDMA in the uplink, making it possible to efficiently utilize bandwidth due to the orthogonally between sub-carriers and by assigning subsets of sub-carriers to individual users which allows for simultaneous data rate transmission from several users and differentiated quality of service for each user. In this paper, wehighlight the technologies behindOFDMA and SC-FDMA and also carry out performance comparison of the two air interface technologies. We brieflydescribe the 3GPP LTE standard, and its implementation using OFDMA and SC-FDMA technology.

MULTIPLE-ACCESS TECHNOLOGY OF CHOICE IN 3GPP LTE

Third-Generation Partnership Project (3GPP) standardizes an Evolved UMTS Terrestrial Radio Access Network (EUTRAN)as air interface in its release 8 LTE. Orthogonal Frequency Division Multiple Access(OFDMA) and Single Carrier-Frequency Division Multiple Access(SC-FDMA)are key technologies for the air interface of mobile broadband systems.It is evident that mobile broadband access technologies are reaching a commonality in the air interface and networking architecture; they are being converged to an IP-based network architecture with OFDMA based air interface technology. The air interface of E-UTRAN is based on OFDMA in downlink and SC-FDMA in the uplink, making it possible to efficientl utilize bandwidth due to the orthogonally between sub-carriers and by assigning subsets of sub-carriers to individual users which allows for simultaneous data rate transmission from several users and differentiated quality of service for each user. In this paper, wehighlight the technologies behindOFDMA and SC-FDMA and also carry out performance comparison of the two air interface technologies. We brieflydescribe the 3GPP LTE standard, and its implementation using OFDMA and SC-FDMA technology.

Research of the Effect of Services on the Aggregate Bandwidth of a Cell Radio Access Network UTRAN of UMTS Standard

UMTS Terrestrial Radio Access Network (UTRAN) dimensioning has been of great interest among network researchers and planners due to the limit of cell bandwidth. This paper investigates the impact of service changes on the nature of radio interface UMTS bandwidth. Finally, OPNET simulation models are developed. The main purpose of modeling was to obtain the dependency of common capacities of the base station for the upward and downward directions on time. Different types of customers were used as the criterion for comparison the values obtained.

LTE-advanced and the evolution of LTE deployments

The fourth generation (4G) wireless technology known as Long Term Evolution (LTE) allows cellular operators to use new and wider spectrum and complements third generation (3G) networks with higher user data rates, lower latency, and a flat Internet Protocol (IP)-based network architecture. The LTE standard was first published in March 2009 as part of the Third Generation Partnership Project (3GPP) Release 8 specifications. The specifications have been in development since 2005 when 3GPP defined LTE requirements and performance goals to significantly improve on the 3GPP Release 6 standard, which was at that point the state of the art. Achieving those goals required an evolution of both the air interface and the network architecture, now known as Evolved UMTS Terrestrial Radio Access Network (E-UTRAN) and Evolved Packet Core (EPC), respectively. The very first commercial LTE networks were deployed on a limited scale in Scandinavia at the end of 2009, and currently, large-scale deployments are taking place in several regions, including North America, Europe, and Asia.

Support of mobile TV over an HSPA network

This paper describes a quality of service (QoS) implementation in the UMTS Terrestrial Radio Access Network (UTRAN) to commercialize mobile television (TV) services with current High Speed Packet Access (HSPA) commercial devices, which do not support a streaming traffic class as defined by the 3rd Generation Partnership Project (3GPP). This implementation allows the mobile operators to offer a high quality of service for the end user in terms of reducing the need for re-buffering during the mobile TV session, while minimizing the impact of the service on the overall radio cell capacity. System level simulations relying on a Tier 1 operator use case have been generated to quantify the benefits streaming users experience due to this QoS implementation in the presence of background traffic in the same radio cell. The impact in terms of radio cell capacity is also evaluated.

Self-optimization of LTE networks utilizing Celnet Xplorer

In order to meet demanding performance objectives in Long Term Evolution (LTE) networks, it is mandatory to implement highly efficient, autonomic self-optimization and configuration processes. Self-optimization processes have already been studied in second generation (2G) and third generation (3G) networks, typically with the objective of improving radio coverage and channel capacity. The 3rd Generation Partnership Project (3GPP) standard for LTE self-organization of networks (SON) provides guidelines on self-configuration of physical cell ID and neighbor relation function and self-optimization for mobility robustness, load balancing, and inter-cell interference reduction. While these are very important from an optimization perspective of local phenomenon (i.e., the eNodeB's interaction with its neighbors), it is also essential to architect control algorithms to optimize the network as a whole. In this paper, we propose a Celnet Xplorer-based SON architecture that allows detailed analysis of network performance combined with a SON control engine to optimize the LTE network. The network performance data is obtained in two stages. In the first stage, data is acquired through intelligent non-intrusive monitoring of the standard interfaces of the Evolved UMTS Terrestrial Radio Access Network (E-UTRAN) and Evolved Packet Core (EPC), coupled with reports from a software client running in the eNodeBs. In the second stage, powerful data analysis is performed on this data, which is then utilized as input for the SON engine. Use cases involving tracking area optimization, dynamic bearer profile reconfiguration, and tuning of network-wide coverage and capacity parameters are presented.

3GPP LTE: The Future of Mobile Broadband

The mobile broadband technologies are reaching a commonality in the air interface and networking architecture; they are being converged to an IP-based network architecture with Orthogonal Frequency Division Multiple Access (OFDMA) based air interface technology. From technical perspective, fundamental goal of mobile broadband is to offer higher data rates with reduced latency. The third Generation Partnership Project (3GPP) presents the Long-Term Evolution (LTE) project in order to accommodate increasing mobile data usage and new multimedia applications. In the near future, with the recent progress made by technical specifications and vendor technology demonstrations LTE will emerge as successor to cellular systems as a broadband wireless solution. This paper provides an overview of 3GPP LTE including its history, features, technology, architecture and future. The technology components include OFDMA air-interface, Multiple-Input and Multiple-Output (MIMO) antenna technology and higher order modulation. The architecture includes Evolved Packet Core (EPC) and Evolved UMTS Terrestrial Radio Access Network (E-UTRAN) components. This paper will concentrate to describe the main functions of the most important network elements. Also, the aim of this paper is to present the future potential of LTE which will make it an inevitable choice for wireless network operators around the globe.

Impacts of air interface admission control and user mobility on UTRAN transport simulations

UMTS Terrestrial Radio Access Network (UTRAN) Transport Network Layer dimensioning has been of great interest among network researchers and planners due to the limit of Iub bandwidth. This paper investigates the potential impacts caused by Connection Admission Control (CAC) mechanism of the air interface and User Mobility (UM) on simulations carried out for the UTRAN transport network domain. Independent from the TNL CAC mechanism of the transport network which is in charge of Iub link bandwidth, the Radio CAC function deals with the highly non-linear resources needed for an attempted connection depending on its specific propagation and interference situation. The consideration of the air interface acting as bottleneck results into a less challenging amount of traffic for the transport domain. In addition, mobile user behaviors, e.g. UM, may dynamically change traffic load at the air interface, and in consequence affect Iub load, which has a very close correlation with cell load. In this work, a simulation model with Radio CAC mechanism and Handover strategies is implemented to study this correlation, and evaluate the UTRAN transport network performance given a limited radio capacity. The analysis on the impacts of the Radio CAC and UM are derived from qualitative simulations.

Performance assessment of next-generation wireless mobile systems

The deployment of third generation (3G) systems such as Universal Mobile Telecommunications System (UMTS) and code division multiple access (CDMA) 1X is now ubiquitous. Furthermore, several operators have already deployed evolved 3G systems such as high speed packet access (HSPA) and 1x evolution data optimized (1× EV-DO). These 3G and evolved 3G systems are based on spread spectrum technologies. Now the industry has begun to focus on next-generation wireless systems based on orthogonal frequency division multiplexing (OFDM) technology, flat-Internet Protocol (IP) architectures, and advanced multiple input-multiple output (MIMO) capabilities. These next-generation technologies, primarily are: 3rd Generation Partnership Project (3GPP)-based evolved UMTS terrestrial radio access network (EUTRAN), also called Long Term Evolution (LTE); 3rd Generation Partnership Project 2 (3GPP2)-based Ultra Mobile Broadband (UMB); and Institute of Electrical and Electronics Engineers (IEEE) 802. 16e-based Worldwide Interoperability for Microwave Access (WiMAX). These technologies are in the final specifications to initial deployment phases in selected markets. This paper provides an overview and performance analysis of these next-generation technologies based on their initial releases. Additionally, a comparative performance analysis of these technologies is also presented.

Internet connection with UMTS

Mobile telecommunication new services are based on data networks specially Internet. These services include http, telnet, ftp, Simple Mail Transfer Protocol, etc. Besides, we recognize a mobile network as a multiuser network. Transmission Control Protocol (TCP)/Internet Protocol which is sensitive to link congestion in wireline data links is also used in wireless networks. In order to improve the system performance, the TCP layer uses flow control and congestion control. Besides, radio link control (RLC) and medium access control sublayers have been introduced to compensate the deficiency of TCP layer in wireless environment. RLC has an important role in quality of service enhancement of the Universal Mobile Telecommunications System (UMTS). In this paper, we review the protocol stack of UMTS Terrestrial Radio Access Network which is based on Third-Generation Partnership Project. Then, we evaluate its layer 2 error control mechanisms and verify TCP over automatic repeat request error control mechanism and finally quality of service improvement results from it in fading channels.

Layered OFDMA and Its Radio Access Techniques for LTE-Advanced

This paper proposes applying the Layered Orthogonal Frequency Division Multiple Access (OFDMA) radio access scheme and its radio access techniques to LTE (Long-Term Evolution)-Advanced to satisfy its system requirements, which are much stricter than those of the Evolved Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access (UTRA) and UMTS Terrestrial Radio Access Network (UTRAN). Layered OFDMA comprises layered transmission bandwidth assignment (bandwidth is assigned to match the required data rate), a layered control signaling structure, and support for layered environments for both the downlink and uplink. Especially in the uplink, an adaptive multi-access scheme with hybrid single-carrier and multicarrier based radio access is applied. Layered OFDMA radio access will support all the functionalities specified in Release 8 LTE and later enhancements. Key radio access techniques such as fast inter-cell radio resource management that takes advantage of remote radio equipment (RRE) so as to realize inter-cell orthogonality, multi-antenna transmission with more antennas, and coverage enhancing techniques are used to achieve a high level of capacity and cell-edge spectrum efficiency.

Cost analysis and efficient radio bearer selection for multicasting over UMTS

AbstractAlong with the widespread deployment of the Third Generation (3G) cellular networks, the fast‐improving capabilities of the mobile devices, content, and service providers are increasingly interested in supporting multicast communications over wireless networks and in particular over Universal Mobile Telecommunications System (UMTS). To this direction, the Third Generation Partnership Project (3GPP) is currently standardizing the Multimedia Broadcast/Multicast Service (MBMS) framework of UMTS. In this paper, we present an overview of the MBMS multicast mode of UMTS. We analytically present the multicast mode of the MBMS and analyze its performance in terms of packet delivery cost under various network topologies, cell types, and multicast users' distributions. Furthermore, for the evaluation of the scheme, we consider different transport channels for the transmission of the multicast data over the UMTS Terrestrial Radio‐Access Network (UTRAN) interfaces. Finally, we propose a scheme for the efficient radio bearer selection that minimizes total packet delivery cost. Copyright © 2008 John Wiley & Sons, Ltd.

Automating network configuration tasks using multi-level modeling

In today's rapidly changing market, an operator needs to introduce new offerings faster and at a lower cost than its competitors. This requires network configuration tasks to be highly automated. However, current network configuration methods have limitations: they use direct-input commands, which is a primitive method that is inflexible and hard to automate; have inadequate modeling and thus cannot represent complex relations and dependencies; and are hard-coded with the underlying model so that model change causes error-prone code change. This paper proposes a general approach for automating network configuration tasks using multi-level modeling: the first level represents the underlying domain; the next level, the inter-relations between models; and the third level, the configuration task business logic. Using multi-level models, a generic engine can be built to auto-generate executable configuration commands. A prototype has been implemented for a UMTS terrestrial radio access network (UTRAN). When tested on a set of representative configuration tasks, the implementation effort and duration are significantly reduced.

QoS control for streaming service in UMTS networks

This paper addresses the end-to-end quality of service (QoS) architecture and mechanisms for Universal Mobile Telecommunications System (UMTS) networks. It presents specific QoS control mechanisms and algorithms for network performance engineering for real time services, in particular streaming applications. The paper concentrates on QoS control in the UMTS terrestrial radio access network (UTRAN) since it is often a bottleneck in end-to-end UMTS bearer performance, especially in the initial stages of network deployment. It discusses several QoS implementation mechanisms, including air interface resource and congestion control, call admission control, mobility control, backhaul bandwidth management, and network element queuing control. Simulation results are presented to show the effectiveness of these controls, and ways they can be used to guarantee streaming bearer performance. In addition, real measurement results are given for a commercial end-to-end UMTS network. © 2007 Alcatel-Lucent.