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This paper discusses the characteristics and key techniques of 3G mobile learning based on cloud services. Our research mainly focuses on mobile learning mode including active mode, passive mode and hybrid mode. And personalized learning method and resource integration approach are applied and analyzed. At last, we propose to employ cloud computing to mobile learning and build basic framework and...
Telecommunications restructuring and 3G license mark the coming of 3G age. As telecommunication departments aim to reorganize business and provide the balanced 3G license, the competition of three telecom operators is becoming increasingly white-hot. China Mo-bile, China Unicom and China Telecom are competing in a tripartite confrontation market structure. They are evenly matched in the new round...
Voice over Internet Protocol (VoIP) over a wireless local area network (WLAN) is poised to become an important Internet application. However, unacceptable VoIP performance in the presence of coexisting traffic from other applications is still one of the major problems standing in its development way. For this point, in this paper, a novel adapted adjustment packet segmentation method is proposed to...
A printed monopole antenna with microstrip-fed Sierpinski fractal geometry for dual wideband application is presented. The operating bands are adjusted with the design of modified Sierpinski triangle (radiating patch), ground plane and scale factor used to create a fractal shape. The simulated 10 dB (VSWR 2:1) reflection bandwidth for first resonant frequency is 60% (1.47 GHz2.7 GHz). It covers GPS,...
In view of the new feature after introducing the relay nodes (RNs) into the conventional cellular networks, a novel soft frequency reuse (SFR)-based inter-cell interference coordination (ICIC) scheme is proposed in the relay enhanced cellular networks. On the basis of original ICIC scheme for conventional cellular network, RNs in the proposed SFR scheme reuses part of neighboring cell-edge bands to...
This paper discusses about RTL design of time domain auto-correlation architecture for two recent standards, i.e.Worldwide Interoperability for Microwave Access Orthogonal Frequency Division Multiple Access (WiMAX OFDMA) and 3rd Generation Partnership Project Long Term Evolution (3GPP LTE). We introduce time domain auto-correlation function to recognize WiMAX preamble and LTE primary synchronization...
Multihop and multipoint transmissions are two of the main features towards an increased spectral efficiency for the LTE-Advanced mobile radio system. Fixed wireless relays with in-band backhauling are considered as a multihop technique in LTE-Advanced. Relays improve cell capacity and cell edge user performance depending on the deployment. In this paper, at first, results for the peak spectral efficiency...
This paper defines a synthetic non-regular Springwald network layout which is easy to take into use in cellular network system simulations. The performance of the non-regular layout was compared with two regular 3GPP simulation scenarios. The benefit of the non-regular layout is that it reflects better the live network deployments and therefore results in more realistic benchmarking metrics. The results...
One of main feature of next generation of mobile networks is an integration of existing cellular systems with other wireless access technologies. In order to realize a seamless vertical handover (inter-RAT handover) among these different access technologies, a multi-interfaced mobile station is expected to communicate simultaneously on various network interfaces (i.e. to be multihomed) to achieve...
In this paper, we investigate carrier frequency synchronization in the downlink of 3GPP Long Term Evolution (LTE). A complete carrier frequency offset estimation and compensation scheme based on standardized synchronization signals and reference symbols is presented. The estimation performance in terms of mean square error is derived analytically and compared to simulation results. The impact of estimation...
The roll-out of UMTS/HSPA networks in 900MHz band offers the possibility to bring third generation and mobile broadband services to new areas with less base station sites and to improve the indoor coverage in the existing UMTS coverage areas. However, a necessary first step in order to take advantage of the mentioned benefits of UMTS/HSPA900 networks is a partial clearance of spectrum in the 900 MHz...
The capacity and coverage area of a cell may vary due to changed environment, insertion or deletion of base stations, or malfunctioning base stations, and wrong parameter selection in the network planning phase. Suboptimal capacity and coverage area leads to the waste of network resources and the lower quality. Reacting on the changed situation manually is very expensive and time consuming. Therefore,...
This paper proposes the configuration of a novel wideband patch antenna system suitable especially for indoor mobile communication applications. This configuration consists of an elevated patch antenna, which has different feed structure from classical patch antenna feed configurations that the antenna is fed by an inverted L-shape structure. The antenna structure is designed, simulated and manufactured...
This paper presents a novel mechanism which increases mobile terminal battery performance. It supports a cell reselection algorithm which decides on which cell, user equipment (UE) is camped on when in idle mode (there is no active radio connection with a mobile network). Study is based on real 3G UTRA network measurements. Authors propose a technique to reduce UE current consumption in idle mode...
In uplink 3GPP Long-Term Evolution (LTE), single-carrier frequency division multiple access (SC-FDMA) is considered partly because of the fact that Peak-to-Average Power Ratio (PAPR) for Multi-Carrier Orthogonal Frequency Division Multiplexing (MC-OFDM) is still a hindrance. But, an unique characteristic of SC-FDMA is that subcarriers have to be assigned by contiguous manner for a specific user, which...
In current cellular networks base stations (BSs) usually perform independent scheduling without coordinating the resource allocation among different cells. This, however, often leads to high interference levels in cellular networks operating with universal frequency reuse, such as the 3GPP UTRAN Long Term Evolution (LTE). Coordinated scheduling between different BSs may mitigate this problem by taking...
We develop a general model based on random coding bounds to explain and predict the coding performance of various type-I and type-II hybrid automatic repeat request (HARQ) schemes based on the bit-interleaved coded modulation (BICM) in 3GPP HSPA. We explore how the intrinsic properties of BICM interact with various transmitter-side (e.g., whether to use the same bit mapping for retransmission) and...
Interference problems in cochannel femtocell networks may cause significant performance degradation for certain femtocell/macrocell users. These problems and potential solutions are recently being investigated within the 3GPP. The goal of the present paper is to review the simulation framework for femtocell networks in 3GPP and briefly summarize some of the important inter-cell interference coordination...
Space-frequency block codes (SFBC) combined with frequency switched transmit diversity (FSTD) is used in the downlink of 3GPP LTE system, where all transmit antennas are collocated at eNodeBs. However, all transmit antennas serving a cell are distributed at the cell edge in edge-excited distributed antenna systems. The performance of SFBC is greatly affected by the different large scale fading from...
With the ever-increasing proliferation of air interfaces that coexist in the same operating area, advanced Radio Resource Management is crucial to take advantage of the available system resources. In this paper, we consider a downlink multi-class heterogeneous network where cells include two co-localized Radio Access Technologies (RAT): WiMAX [1] and UMTS [2]. We propose a Centralised Access Control...
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