NTT DoCoMo

About: NTT DoCoMo is a based out in . It is known for research contribution in the topics: Base station & Mobile station. The organization has 4032 authors who have published 8655 publications receiving 160533 citations.

Method and apparatus for network virtualization

Abstract: A method for implementing an entity of a network by virtualizing said network entity and implementing it on one or more servers each acting as an execution unit for executing thereon one or more applications running and/or one or more virtual machines running on said execution unit, each of said application programs or virtual machines running on a server and implementing at least a part of the functionality of said network entity being called a virtual network function VNF module, wherein a plurality of said VNF modules together implement said network entity to thereby form a virtual network function VNF, said method comprising the steps of: obtaining m key performance indicators (KPI) specifying the required overall performance of the VNF, obtaining n performance characteristics for available types of execution units, determining one or more possible deployment plans based on the obtained m KPI and n performance characteristics, each deployment plan specifying the number and types of execution units, such that the joint performance of VNF modules running on these execution units achieves the required overall performance of the VNF.

Handling CCI and ICI in OFDMA femtocell networks through frequency scheduling

Abstract: Femtocells have a strong potential for increasing the efficiency and coverage of next-generation broadband wireless networks. In this paper, a co-channel framework for the coexistence of orthogonal frequency division multiple access (OFDMA) based macrocell and femtocell wireless networks is proposed. It is based on utilizing the resource blocks of macrocell-associated mobile stations (mMSs) that are far away to a femtocell base station (fBS), therefore avoiding strong interference that may occur between a femtocell and close-by mMSs. An avoidance method that jointly utilizes the spectrum sensing results as well as scheduling information obtained from the macrocell base station (mBS) is introduced. Moreover, the impact of inter-carrier interference (ICI) from the mMSs in the uplink is discussed and evaluated through simulations.

Stochastic Geometry Analysis of Cellular Networks

Abstract: Achieve faster and more efficient network design and optimization with this comprehensive guide. Some of the most prominent researchers in the field explain the very latest analytic techniques and results from stochastic geometry for modelling the signal-to-interference-plus-noise ratio (SINR) distribution in heterogeneous cellular networks. This book will help readers to understand the effects of combining different system deployment parameters on key performance indicators such as coverage and capacity, enabling the efficient allocation of simulation resources. In addition to covering results for network models based on the Poisson point process, this book presents recent results for when non-Poisson base station configurations appear Poisson, due to random propagation effects such as fading and shadowing, as well as non-Poisson models for base station configurations, with a focus on determinantal point processes and tractable approximation methods. Theoretical results are illustrated with practical Long-Term Evolution (LTE) applications and compared with real-world deployment results.

Location reporting method and related mobile communication terminal

Abstract: Menu data supplied from an IP server 500 to a mobile station 101 is embedded with a location information substitution data string “NULLAREA” together with a URL of a particular IP server 500. The mobile station 101, upon detection of the location information substitution data string from a menu data selected by the user, determines whether location information can be transmitted to the IP server 500. In the case where the determination is that the transmission is permitted, the mobile station 101 detects its location information and, after substituting the location information for the location information substitution data string, transmits the data to the IP server 500.

Position location technologies using signal strength in cellular systems

Abstract: This paper proposes a novel algorithm to locate a mobile terminal (MS) in a cellular system. The proposed algorithm is based on signal strength measurements. It considers the fluctuation in received signal strength due to shadowing, and obtains probability density functions (PDFs) of the propagation distances. An overall PDF, obtained by combining the PDFs, is used to determine the MS location. Results obtained from computer simulations and field experiments show that the proposed algorithm is more accurate than the conventional cell-based algorithm.