Modelling Load Balancing and Carrier Aggregation in Mobile Networks

In this paper, we study the performance of multicarrier mobile networks. Specifically, we analyze the flow-level performance of two inter-carrier load balancing schemes and the gain engendered by Carrier Aggregation (CA). CA is one of the most important features of HSPA+ and LTE-A networks; it allows devices to be served simultaneously by several carriers. We propose two load balancing schemes, namely Join the Fastest Queue (JFQ) and Volume Balancing (VB), that allow the traffic of CA and non-CA users to be distributed over the aggregated carriers. We then evaluate the performance of these schemes by means of analytical modeling. We show that the proposed schemes achieve quasi-ideal load balancing. We also investigate the impact of mixing traffic of CA and non-CA users in the same cell and show that performance is practically insensitive to the traffic mix.Comment: 8 pages, 6 figures, submitted to WiOpt201

LTE Advanced: Technology and Performance Analysis

Wireless data usage is increasing at a phenomenal rate and driving the need for continued innovations in wireless data technologies to provide more capacity and higher quality of service. In October 2009, 3rd Generation Partnership Project (3GPP) submitted LTE-Advanced to the ITU as a proposed candidate IMT-Advanced technology for which specifications could become available in 2011 through Release-10 . The aim of “LTE-Advanced” is to further enhance LTE radio access in terms of system performance and capabilities compared to current cellular systems, including the first release of LTE, with a specific goal to ensure that LTE fulfills and even surpass the requirements of “IMT-Advanced” as defined by the International Telecommunication Union (ITU-R) . This thesis offers an introduction to the mobile communication standard known as LTE Advanced, depicting the evolution of the standard from its roots and discussing several important technologies that help it evolve to accomplishing the IMT-Advanced requirements. A short history of the LTE standard is offered, along with a discussion of its standards and performance. LTE-Advanced details include analysis on the physical layer by investigating the performance of SC-FDMA and OFDMA of LTE physical layer. The investigation is done by considering different modulation schemes (QPSK, 16QAM and 64QAM) on the basis of PAPR, BER, power spectral density (PSD) and error probability by simulating the model of SC-FDMA & OFDMA. To evaluate the performance in presence of noise, an Additive White Gaussian Noise (AWGN) channel was introduced. A set of conclusions is derived from our results describing the effect of higher order modulation schemes on BER and error probability for both OFDMA and SC-FDMA. The power spectral densities of both the multiple access techniques (OFDMA and SC-FDMA) are calculated and result shows that the OFDMA has higher power spectral density.fi=Opinnäytetyö kokotekstinä PDF-muodossa.|en=Thesis fulltext in PDF format.|sv=Lärdomsprov tillgängligt som fulltext i PDF-format

Energy saving scheme for multicarrier HSPA + under realistic traffic fluctuation

The final publication is available at Springer via http://dx.doi.org/10.1007/s11036-015-0656-6In the near future, an increase in cellular network density is expected to be one of the main enablers to boost the system capacity. This development will lead to an increase in the network energy consumption. In this context, we propose an energy efficient dynamic scheme for HSDPA + (High Speed Downlink Packet Access-Advanced) systems aggregating several carriers and which adapts dynamically to the network traffic. The scheme evaluates whether node-B deactivation is feasible without compromising the user flow throughput. Furthermore, instead of progressive de-activation of carriers and/or node-B switch-off, we evaluate the approach where feasible combination of inter-site distance and number of carriers is searched to obtain best savings. This is done by also considering the effect of transition delays between network configuration changes. The solution exploits the fact that re-activation of carriers might permit turning off other BSs earlier at relatively higher load than existing policies. Remote electrical downtilt is also considered as a means to maximize the utilization of higher modulation and coding schemes in the extended cells. This approach promises significant energy savings when compared with existing policies - not only for low traffic hours but also for medium load scenarios.Peer ReviewedPostprint (author's final draft

4G Technology Features and Evolution towards IMT-Advanced

Kiinteiden- ja mobiilipalveluiden kysyntä kasvaa nopeasti ympäri maailmaa. Älykkäiden päätelaitteiden, kuten iPhone:n ja Nokia N900:n markkinoilletulo yhdistettynä näiden korkeaan markkinapenetraatioon ja korkealuokkaiseen käyttäjäkokemukseen lisäävät entisestään palveluiden kysyntää ja luovat tarpeen jatkuvalle innovoinnille langattomien teknologioiden alalla tavoitteena lisäkapasiteetin ja paremman palvelunlaadun tarjoaminen. Termi 4G (4th Generation) viittaa tuleviin neljännen sukupolven mobiileihin langattomiin palveluihin, jotka International Telecommunications Union:in Radiocommunication Sector (ITU-R) on määritellyt ja nimennyt International Mobile Telecommunications-Advanced (IMT-Advanced). Nämä ovat järjestelmiä, jotka pitävät sisällään IMT:n ne uudet ominaisuudet, jotka ylittävät IMT-2000:n vaatimukset. Long Term Evolution-Advanced (LTE-Advanced) ja IEEE 802.16m ovat IMT-A sertifiointiin lähetetyt kaksi pääasiallista kandidaattiteknologiaa. Tässä diplomityössä esitellään kolmannen sukupolven järjestelmien kehityspolku LTE:hen ja IEEE 802.16e-2005 asti. Lisäksi työssä esitetään LTE-Advanced:n ja IEEE 802.16m:n uudet vaatimukset ja ominaisuudet sekä vertaillaan näiden lähestymistapoja IMT-A vaatimusten täyttämiseksi. Lopuksi työssä luodaan katsaus LTE ja IEEE 802.16e-2005 (markkinointinimeltään Mobile WiMAX) -järjestelmien markkinatilanteeseen.The demand for affordable bandwidth in fixed and mobile services is growing rapidly around the world. The emergence of smart devices like the iPhone and Nokia N900, coupled with their high market penetration and superior user experience is behind this increased demand, inevitably driving the need for continued innovations in the wireless data technologies industry to provide more capacity and higher quality of service. The term "4G" meaning the 4th Generation of wireless technology describes mobile wireless services which have been defined by the ITU's Radiocommunication Sector (ITU-R) and titled International Mobile Telecommunications-Advanced (IMT-Advanced). These are mobile systems that include the new capabilities of IMT that go beyond those of IMT-2000. Long Term Evolution-Advanced (LTE-Advanced) and IEEE 802.16m are the two main candidate technologies submitted for IMT-Advanced certification. This thesis reviews the technology roadmap up to and including current 3G systems LTE from the 3rd Generation Partnership Project (3GPP) and IEEE 802.16e-2005 from the Institute of Electrical and Electronics Engineers (IEEE). Furthermore, new requirements and features for LTE-Advanced and IEEE 802.16m as well as a comparative approach towards IMT-Advanced certification are presented. Finally, the thesis concludes with a discussion on the market status and deployment strategies of LTE and IEEE 802.16e-2005, or Mobile WiMAX as it is being marketed

PROCESS FOR BREAKING DOWN THE LTE SIGNAL TO EXTRACT KEY INFORMATION

The increasingly important role of Long Term Evolution (LTE) has increased security concerns among the service providers and end users and made security of the network even more indispensable. The main thrust of this thesis is to investigate if the LTE signal can be broken down in a methodical way to obtain information that would otherwise be private; e.g., the Global Positioning System (GPS) location of the user equipment/base station or identity (ID) of the user. The study made use of signal simulators and software to analyze the LTE signal to develop a method to remove noise, breakdown the LTE signal and extract desired information. From the simulation results, it was possible to extract key information in the downlink like the Downlink Control Information (DCI), Cell-Radio Network Temporary Identifier (C-RNTI) and physical Cell Identity (Cell-ID). This information can be modified to cause service disruptions in the network within a reasonable amount of time and with modest computing resources.Defence Science and Technology Agency, SingaporeApproved for public release; distribution is unlimited

Vývoj standardů mobilních sítí

Import 21/10/2013This bachelor thesis deals primarily with a development of LTE technologies and its possibilities of deployment in the Czech Republic and abroad. The thesis is initially focused on the development of mobile network standards since the advent of 3rd generation networks in Release 99 up to the newest Release 12 where the main telecommunication technologies are continuously described along with their advantages. As the LTE represents next evolution step in a field of mobile data transmission, the comparison of LTE and HSPA+ physical layers is also included. Among other it describes information blocks from transport channel over the transmission path and regaining of user data. The development of LTE networks in the world deals with an actual progress of the deployment of this technology. In detail, there are described countries where the LTE is in a commercial service among with a comparison of used frequency bands. Addressing with issue of development and deployment of LTE in the Czech Republic is a content of the last part. With regard to the current network state of each provider, it is also focused on legislation, backbone networks and frequency planning which is closely related to the forthcoming auction of the Digital Dividend.Tato bakalářská práce pojednává především o vývoji LTE technologíí a jejich možnostech nasazení v České Republice a ve světě. Práce se nejprve zaměřuje na vývoj mobilních standardů od nástupu sítí třetí generace, Release 99, až po doposud nejnovější Release 12, kde jsou postupně probrány vrcholové telekomunikační technologie a jejich přednosti. V práci jsou dále popsány rozdíly fyzických vrstev mezi technologiemi HSPA+ a LTE, jelikož se jedná o další evoluční krok v oblasti datových přenosů. Popis obsahuje blokové srovnání od samotné inicializace transportního kanálu, po přenosovou cestu a opětovného získání užitečné informace. Vývoj LTE sítí ve světě pojednává o aktuálním stavu vývoje a rozšíření této technologie. Podrobně jsou zde popsány země, kde se LTE používá spolu se srovnáním použitých frekvenčních pásem. Poslední část řeší otázku vývoje a nasazení LTE v České Republice. S ohledem na aktuální stav sítí jednotlivých operátoru je sekce zaměřena také na legislativu, páteřní sítě a frekvenční plánování, s čímž souvisí také očekáváná aukce z digitální dividendy.440 - Katedra telekomunikační technikyvelmi dobř

MBMS—IP Multicast/Broadcast in 3G Networks

In this article, the Multimedia Broadcast and Multicast Service (MBMS) as standardized in 3GPP is presented. With MBMS, multicast and broadcast capabilities are introduced into cellular networks. After an introduction into MBMS technology, MBMS radio bearer realizations are presented. Different MBMS bearer services like broadcast mode, enhanced broadcast mode and multicast mode are discussed. Streaming and download services over MBMS are presented and supported media codecs are listed. Service layer components as defined in Open Mobile Alliance (OMA) are introduced. For a Mobile TV use case capacity improvements achieved by MBMS are shown. Finally, evolution of MBMS as part of 3GPP standardization is presented

A review of traditional cost system versus activity based costing approaches

In the last two decades, business environment has been changing rapidly with fierce global competition. Firms using the traditional costing system were forced to change from their old system traditional-cost method and to accept the newer cost system, better known as the activity based on costing (ABC system). The new system is able to support and enhance decision making of the decision makers, besides being adaptable to the new business environment. Therefore, this paper aimed to review the applications and importance of both traditional cost system and ABC system for business decision making, and compare the results of ABC and the traditional costing systems via literature reviews of works by previous authors. The results reflected that activity based on the costing system is a better system comparing to the traditional costing systems. ABC system enhances decision making of the interested user with its better adaptable costing features to support the new business environment and global business competition. It thus creates a more sustainable source of competitive advantage. In addition, it identifies the under-costed and over-costed of the products of a firm