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This paper presents a methodology for evaluating the quality of service provided by a cellular network for background services, such as e-mail and text messaging. Data collected from drive testing were used as the means to evaluate different drive routes on a Universal Mobile Telecommunications System (UMTS) network. Although one type of cellular network was tested, this methodology may be readily...
The 3GPP (Third Generation Partnership Project) LTE (Long Term Evolution) activity towards the evolved UMTS (Universal Mobile Telecommunications System) Terrestrial Radio Access, which is known as E-UTRA, was started in November 2004 and recently culminated in the Release 8 of the 3GPP technical specifications, cf. e.g. the technical specifications 3GPP TS 36.101 and 3GPP TS 36.201. In the case of...
Coordinated Multipoint (CoMP) transmission techniques have been considered as tools to improve cell-edge and average data throughput for LTE-Advanced. First investigations of CoMP techniques in homogeneous hexagonal macro layouts have shown that interference coordination needs to involve dominant interferers to allow significant gain. Therefore, in the present paper the application of CoMP in a heterogeneous...
Next Generation Wireless Networks (NGWNs) will be the convergence of fixed and mobile networking technologies, e.g., Ethernet, Wireless LAN, 2G/3G/4G, etc. This united ubiquitous network will consist of billions of mobile devices, each with multiple networking interfaces. These interfaces may belong to a set of diverse link layer technologies. Internet Protocol (IP) shall potentially be used as the...
Existing transmission control protocol (TCP) and TCP-Friendly flows suffer from unpredictable losses and delay over wireless links because such factors may cause sending rate throttling and lower the reactivity of transmission control. This paper presents a cross-layer approach to adapt TCP-Friendly rate control (TFRC) to these two factors of 3-rd generation (3G) wireless links. For effective adaptation,...
In W-CDMA (Wideband Code Division Multiple Access)/UMTS (Universal Mobile Telecommunications System), multiuser contention brought by packet scheduling in MAC-layer causes the issue that effectiveness requirements and fairness requirements for TCP in transport-layer are difficult to be guaranteed simultaneously. In order to solve this problem, we propose a novel scheme CL-AACS (active ACK control...
Two main draft standards were submitted in October 2009 as candidate technologies for IMT-Advanced, namely IEEE 802.16m and 3GPP LTE-Advanced. However, several details on their functionalities are still open and the research community is racing towards the complete definition of the revolutionary next fourth generation mobile, 4G. In this framework the European Celtic project WINNER+ is bridging together...
As heterogeneous wireless networks are deployed and users need more flexible mobility services, there has been a lot of research work about interworking mechanism between widely deployed 3G network and rapidly boarded WLAN (wireless local area network). On the other side, TD-SCDMA (time division-synchronous code division multiple access), which combines all the advantage of the TDD (time-division...
Femtocells technology has emerged as a promising solution to provide the indoor coverage in the 3rd generation (3G) long-term evolution (LTE) and its advanced (LTE-Advanced) networks. In this paper, we propose a two-step interference coordination scheme to deal with the interference between femtocells in LTE-Advanced networks with carrier aggregation. Each femtocell is assigned a carrier that is non-overlapping...
ARTIST4G is an integrated project addressing objective 1.1 of the seventh framework program of the European commission: the network of the future. A credible framework is proposed in order to tackle the problem of true ubiquity in the network through proper management of the interference. The three pillars of the project being interference avoidance (at the transmitter), interference exploitation...
Relaying is expected to be one key element of the future cellular networks. This paper focuses on 3GPP LTE-Advanced network incorporated with Type I relay nodes. We first present the required radio resource management (RRM) framework which includes routing, resource partition and scheduling functions. Then two RRM strategies are suggested: one with the conventional cellular settings, the other with...
In this paper, the deployment of a LTE (Long Term Evolution) femtocell network is analyzed in downlink. The study focuses on the assessment of the induced interference on a femtocell by both femtocells and macrocells networks. This case corresponds to a shared channels scenario. The radio conditions that can be expected for femtocell and macrocell users, and thus the overall throughput that can be...
Cellular technology is widely used for Internet access, also because most operators are now offering Mbit/s data rates at affordable prices. Many studies analyzed the performance of these networks using analytical or simulation approaches. However, due to lack of data from operational environments, very little is known about the performance of real cellular networks. In this paper, we assess the performance...
As one of the most promising physical layer technology for next generation cellular system, cooperative multiple points transmission (COMP) brings significant changes to wireless system, on RRM part especially. How to select Cooperative Set (CS) is critical issue for COMP. Based on geometry criteria, this paper proposes two methods of cooperative area selections, `UE centric' and `Networks pre-defined'...
The target of the paper is to provide guidelines for indoor planning and optimization using an outdoor-to-indoor repeater or a dedicated indoor system. The paper provides practical information for enhancing the performance of high-speed downlink packet access (HSDPA) in an indoor environment.
Non-static transmission time interval (TTI) strategy is investigated in this paper, in order to improve the available potential performance of the enhanced uplink dedicated channel in universal telecommunication radio access low chip rate time division duplex system (UTRA LCR TDD). This strategy introduces a joint support of two kinds of TTI, 20ms and 5ms TTI. For 5ms TTI is competitive at end-to-end...
Recently, Long Term Evolution (LTE) has developed a femtocell for indoor coverage extension. However, interference problem between the femtocell and the macrocell should be solved in advance. In this paper, we propose an interference management scheme in the LTE femtocell systems using Fractional Frequency Reuse (FFR). Under the macrocell allocating frequency band by the FFR, the femtocell chooses...
In this paper, adjustable subcarrier allocation algorithm is proposed for both system spectral efficiency and user-throughput fairness (or throughput requirement). There exists trade-off between two performance metrics. The proposed subcarrier allocation method can easily coordinate system performance between spectral efficiency and user-throughput fairness. To achieve adjustable goal, we define cost...
3 GPP long term evolution (LTE) enhances the wireless communication standards UMTS and HSDPA towards higher throughput. A throughput of 150 Mbit/s is specified for LTE using 2??2 MIMO. For this, highly punctured Turbo codes with rates up to 0.95 are used for channel coding, which is a big challenge for decoder design. This paper investigates efficient decoder architectures for highly punctured LTE...
The advanced wireless technologies make vehicle-to-vehicle communication possible. However, vehicular network has a limitation in terms of network topology rapidly change, which causes discontinuous connection. To support seamless connection, horizontal and vertical handovers are required. The good handover mechanism should take network parameters, user requirements, and application QoS into account...
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