Olivier Marce

Performances evaluation of different algorithms for PCIs self configuration in LTE

Nowadays, network operators are basically facing two problems: the fast number of subscribers growth and the network congestion. To solve these problems, network operators increase the number of cells, make cells smaller and reserve a subpart of frequencies to Femto cells to offload data traffic. As a consequence, networks manual planning demands a lot of efforts and its cost increases. Self-configuring and self-optimizing mechanisms would be vital to operators to reduce manual planning. This article focuses on the application of these mechanisms in LTE and more specifically on the procedure of Automated configuration of Physical Cell Ids (PCIs). This procedure aims at avoiding conflicts in PCIs allocation. In this article, we first evaluate the performances of 3 relabeling algorithms applied on graphs representing real LTE Macro networks: Random Relabeling algorithm (RR), Smallest available Value algorithm (SV), Distance 3 neighbour label algorithm (D3). Then, we evaluate the performances of the best algorithm applied on graphs representing real LTE networks where Femto cells are connected to Macro cells. Here, we answer the following question: is the selected relabeling algorithm still efficient when we extend its application to Femto cells?.

Femtocells: The HOMESNET vision

This paper presents the vision shared by partners from the CELTIC project HOMESNET about Femto Base Station deployed at Home, i.e. Home Base Station (HBS). Three of the main aspects under study are presented. The challenges in HBS self-organizing, including femto-macro coexistence, are explained and methodology for successful self-organization is proposed. To achieve very low radio emission at home or constrained environment like hospitals, an architectural option for HBS relying on Radio over Fiber approach is proposed. Last, an innovative use case for HBS, allowing indoor emergency telemedicine scenarios, whereby, paramedics are able to seamlessly exploit HBS at the patient or neighboring apartment, is described. The expected impacts of the HOMESNET project and the planned next steps toward this vision are presented.

Minimizing Routing Delay Variation in Case of Mobility

One of the main challenges in all-IP networks is the development of suitable mobility solution. Mobile IP (MIP) presents the standard protocol used to support IP mobility. However, MIP is inadequate for real-time applications and inter-domain mobility (when a mobile node performs handover between two Autonomous Systems (AS)). In this paper, we propose an efficient approach to manage inter-domain handover in attempt to reduce the delay variation which cause service disruption. We propose an algorithm to select routes connecting two ASs such as the delay variation is minimal. First, we prove that the corresponding graph problem is NP-complete. Then, we propose a global strategy to find routes for each source-destination pair of ASs giving a small delay variation. Finally, we measured by simulation the efficiency of this strategy in comparison with its algorithmic time complexity.

Mobile users assignment control strategies for LTE networks

Actual mobile operators are facing capacity issues of their networks and the growth of their energy consumption. This paper presents two strategies to control the assignment of mobile users in heterogeneous LTE networks. The objective of controlling is to improve the offered QoS while reducing the energy consumption of serving base stations. The control proposed in these strategies is local; both strategies aim at selecting the femtocell or macrocell that will serve a mobile user making a handover request. Moreover, as the femtocells can be switched off and the macrocells have to remain always on, both strategies offload mobile users to/from the selected femtocell/macrocell, that is, the mobile user may be moved from a femtocell to a macrocell or the other way around. The move is legitimate if the power consumption is lower and the QoS offered to the mobile user is not sacrified. Using real network data, simulations are done to evaluate these strategies in terms of power consumption and energy intensity of the network, the percentage of served mobile users, allocated capacity, and deactivated femtocells.

Market Analysis and Exploitation

This paper goes through different business exploitation opportunities that may arise around User-centric Wireless Local Loop—ULOOP-project [1] concepts. This market analysis takes as a starting point the initial approach covered by “D2.2: ULOOP socio-economic sustainability report” [2], a public document released during the first year of the project. On top of this deliverable, a deeper analysis on operators’ (incl. service providers) market opportunities is performed. Additionally, other telco market stakeholders’ perspective, like infrastructure and device vendors’, is considered.