oalib
Search Results: 1 - 10 of 100 matches for " "
All listed articles are free for downloading (OA Articles)
Page 1 /100
Display every page Item
LTE and WiMAX: Comparison and Future Perspective  [PDF]
Ismat Aldmour
Communications and Network (CN) , 2013, DOI: 10.4236/cn.2013.54045
Abstract:

Two wireless technologies, WiMAX based on IEEE standards and LTE standardized by 3GPP, are two competing technologies, nevertheless, are very technically similar. This competition started with the advent of their pre-4G versions (802.16e for Mobile WiMAX and 3GPP release 8 for LTE) and continued with the advent of their 4G versions (WiMAX 2.0 based on IEEE 802.16 m and LTE-Advanced standardized by Release 10). It looks that the competition ended with the advantage of LTE. Plans are set for WiMAX to migrate/integrate with LTE in a multiple heterogeneous access technology mode. This article addresses the technical similarities and differences that advantage one technology over the other technology in order to determine which of these factors might have contributed to LTE winning. Nontechnical factors of commercial and historical nature which might also advantage one technology over the other one are also explored. Finally, current activities in the standardization of both WiMAX and LTE are presented with a perspective on the prospects of both technologies.

Robust methods for LTE and WiMAX dimensioning  [PDF]
Laurent Decreusefond,Eduardo Ferraz,Philippe Martins,Thanh-Tung Vu
Computer Science , 2012,
Abstract: This paper proposes an analytic model for dimensioning OFDMA based networks like WiMAX and LTE systems. In such a system, users require a number of subchannels which depends on their \SNR, hence of their position and the shadowing they experience. The system is overloaded when the number of required subchannels is greater than the number of available subchannels. We give an exact though not closed expression of the loss probability and then give an algorithmic method to derive the number of subchannels which guarantees a loss probability less than a given threshold. We show that Gaussian approximation lead to optimistic values and are thus unusable. We then introduce Edgeworth expansions with error bounds and show that by choosing the right order of the expansion, one can have an approximate dimensioning value easy to compute but with guaranteed performance. As the values obtained are highly dependent from the parameters of the system, which turned to be rather undetermined, we provide a procedure based on concentration inequality for Poisson functionals, which yields to conservative dimensioning. This paper relies on recent results on concentration inequalities and establish new results on Edgeworth expansions.
The Analysis of Mobile WiMAX and LTE using MIMO technique  [cached]
Roopali Garg,Shafi Singla
International Journal of Computers & Technology , 2013,
Abstract: A quality of service is a fundamental component of the 4G broadband network for satisfactory service delivery by evolving internet application to end user, and managing the network resources. The 4G technology has emerged one of the most fruitful technologies as it supports large number of applications including VOIP, video conferencing, file transfer, video streaming and web browsing. IEEE 802.16E, IEEE 802.16M and LTE along with various application and QoS requirement also support Multiple-Input-multiple-output (MIMO) techniques including Spatial Multiplexing (SM), Space Time Block Coding(STBC) and Eigen Beam-forming (BM).In the paper we will study Physical, MAC layer of WiMAX and LTE. We will also study MIMO techniques. In this paper the detailed study of the throughput for a MIMO mobile WiMAX system and LTE under two different PHY PER QoS threshold. Various modulation and channel coding techniques have been applied.
In Quest of the Better Mobile Broadband Solution for South Asia Taking WiMAX and LTE into Consideration  [PDF]
Nafiz Imtiaz Bin Hamid,Md. R. H. Khandokar,Taskin Jamal,Md. A. Shoeb,Md. Zakir Hossain
Computer Science , 2010,
Abstract: Internet generation is growing accustomed to having broadband access wherever they go and not just at home or in the office, which turns mobile broadband into a reality. This paper aims to look for a suitable mobile broadband solution in the South Asian region through comparative analysis in various perspectives. Both WiMAX and LTE are 4G technologies designed to move data rather than voice having IP networks based on OFDM technology. Proving competency in various significant aspects WiMAX and LTE already have made a strong position in telecommunication industry. Again, because of certain similarities in technology; they aren't like technological rivals as of GSM and CDMA. But still they are treated as opponents and viewed as a major threat in case of the flourishing of each other. Such view point is surely not conducive for getting the best out of them. In this paper various aspects and applications of WiMAX and LTE for deployment have been analyzed. South Asia being the residence of an enormous number of people presents an exciting opportunity for mobile operators, developers and internet service providers. So, every consideration that has been made here also correlates successfully with south Asia i.e. how mass people of this region may be benefited from it. As a result, it might be regarded as a good source in case of making major BWA deployment decisions in this region. Besides these, it also opens the path for further research and thinking in this issue.
Novel Dual-Band Design of Planar Dipole Array for 4G LTE/WiMAX Access Points  [PDF]
Jui-Han Lu,Shi-Wei You
International Journal of Antennas and Propagation , 2011, DOI: 10.1155/2011/638034
Abstract: A novel planar dipole array with dual-band operation for LTE/WiMAX access points is proposed. The impedance bandwidths, determined from , can reach about 525/747?MHz (20.2/21.3%) for the 2.6/3.5?GHz operating bands, respectively, which are covering the required bandwidth for LTE (2.5 ~ 2.7?GHz) and WiMAX (3.3 ~ 3.7?GHz) system. This proposed dual-band dipole array also provides maximum peak antenna gains and efficiencies of 7.3/7.5?dBi and 89/75% across 2.6/3.5?GHz bands, respectively, with good omnidirectional radiation pattern in XY-plane. 1. Introduction Recently, LTE (Long-Term Evolution) and WiMAX (Worldwide Interoperability for Microwave Access) systems for the Fourth-Generation (4G) mobile communication has attracted high attention for broadband access in wireless metropolitan area network (WMAN) environment. For the LTE/WiMAX base stations or access points, the high-gain array antenna with omnidirectional radiation in the azimuthal plane is usually required for long-distance communication. The related array designs had been presented by using two dipole arrays [1], collinear array antenna with three in-phase half-wavelength radiating elements [2], and four-element collinear array antenna [3]. However, these above array antennas were focused on the single-band operation. For dual-band operation, only the array design [4] had been proposed by using one dipole antenna for 2.4?GHz and array antenna for 5.2?GHz WLAN communication. And, there was a disadvantage of lower antenna gain (less than 4?dBi), which was unsuitably in the practical applications for LTE/WiMAX access points. Meanwhile, dual-band dipole array for LTE/WiMAX applications is very scant in the open literature. Therefore, in this paper, we propose a novel planar dual-band dipole array mainly comprises two dipole arrays arranged back to back, and can be easily constructed by printing on both sides of a dielectric substrate (see the geometry shown in Figure 1). By properly adjusting the arms’ lengths of each unsymmetrical dipole element, the operating bandwidths (VSWR ≦ 2.0) can reach about 525/747?MHz (20.2/21.3%), which are enough for LTE and WiMAX system. Also, the proposed dipole array provides maximum peak antenna gains and efficiencies of 7.3/7.5?dBi and 89/75% across 2.6/3.5?GHz bands, respectively, with good omnidirectional radiation pattern in the azimuthal plane and narrow-beamwidth pattern in the elevation plane. Details of the proposed dual-band dipole array designs are described, and experimental results for the obtained high-gain performance are presented and discussed.
Mobile Broadband Possibilities considering the Arrival of IEEE 802.16m & LTE with an Emphasis on South Asia  [PDF]
Nafiz Imtiaz Bin Hamid,Md. Zakir Hossain,Md. R. H. Khandokar,Taskin Jamal,Md. A. Shoeb
Computer Science , 2010,
Abstract: This paper intends to look deeper into finding an ideal mobile broadband solution. Special stress has been put in the South Asian region through some comparative analysis. Proving their competency in numerous aspects, WiMAX and LTE already have already made a strong position in telecommunication industry. Both WiMAX and LTE are 4G technologies designed to move data rather than voice having IP networks based on OFDM technology. So, they aren't like typical technological rivals as of GSM and CDMA. But still a gesture of hostility seems to outburst long before the stable commercial launch of LTE. In this paper various aspects of WiMAX and LTE for deployment have been analyzed. Again, we tried to make every possible consideration with respect to south Asia i.e. how mass people of this region may be benefited. As a result, it might be regarded as a good source in case of making major BWA deployment decisions in this region. Besides these, it also opens the path for further research and in depth thinking in this issue.
Vertical Handoff In Wlan-Wimax-Lte Heterogeneous Networks Through Gateway Relocation  [PDF]
L. Nithyanandan,I. Parthiban
International Journal of Wireless & Mobile Networks , 2012,
Abstract: In wireless communication new technologies emerges regularly with faster data rates and larger coverage area. Therefore the forthcoming challenge is to make the best possible use of the available heterogeneous network. For connecting mobile between heterogeneous networks vertical handoff is mandatory. IP Multimedia Subsystem is an emerging architecture for interworking of heterogeneous networks. In this paper we used WLAN/WiMAX/LTE heterogeneous networks. Coupling architectures such as tight coupling and loose coupling are considered. In order to reduce the latency two mechanisms such as neighbour bandwidth reservation and gateway relocation are employed. The parameters such as vertical handoff delay, Mobile scanning interval activity, neighbouring advertisement received are obtained. From the simulation it is inferred that tight coupling with gateway relocation is performingbetter from handover point of view.
Mobile Broadband: Comparison of Mobile WiMAX and Cellular 3G/3G+ Technologies  [PDF]
Muhammad Khalil Shahid,Tang Shoulian,Ao Shan
Information Technology Journal , 2008,
Abstract: This study not only provides the overview of all kind of broadband technologies, both wire-line and wireless, but also compares the two prominent broadband mobile technologies- 3G Mobile Cellular and Mobile WiMAX. It compares technical as well as spectrum aspects. In order to make this research comprehensive, WIMAX is compared with existing 3G/3G+ Cellular technologies like High Speed Packet Access (HSPA) as well as with future technologies like Long Term Evolution/Ultra Mobile Broadband (LTE/UMB) by making some assumptions to get some practical results. This study concludes that, in the wake of bandwidth hunger new applications and services, Mobile WiMAX has a great potential to become main stream technology and it has become both threat and opportunity for Mobile Cellular operators.
Hardware-Optimized Lattice Reduction Algorithm for WiMax/LTE MIMO Detection using VLSI  [PDF]
R.Ragumadhavan?
International Journal of Computer Science and Mobile Computing , 2013,
Abstract: This paper presents the first ASIC implementation of an LR algorithm which achieves MLdiversity. The VLSI implementation is based on a novel hardware-optimized LLL algorithm that has 70%lower complexity than the traditional complex LLL algorithm. This reduction is achieved by replacing all thecomputationally intensive CLLL operations (multiplication, division and square root) with low-complexityadditions and comparisons. The VLSI implementation uses a pipelined architecture that produces an LRreducedmatrix every 40 cycles, which is a 60% reduction compared to current implementations. Theproposed design was synthesized in both 130μm and 65nm CMOS resulting in clock speeds of 332MHz and833MHz, respectively. The 65nm result is a 4X improvement over the fastest LR implementation to date. Theproposed LR implementation is able to sustain a throughput of 2Gbps, thus achieving the high data ratesrequired by future standards such as IEEE 802.16m (WiMAX) and LTE-Advanced.
WiMAX, LTE, and WiFi Interworking  [PDF]
Rashid A. Saeed,Ahmed A. M. Hassan Mabrouk,Amitava Mukherjee,Francisco Falcone
Journal of Computer Networks and Communications , 2010, DOI: 10.1155/2010/754187
Abstract:
Page 1 /100
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.