Mobile telephony

About: Mobile telephony is a research topic. Over the lifetime, 38008 publications have been published within this topic receiving 553646 citations.

5G Mobile and Wireless Communications Technology

Abstract: Written by leading experts in 5G research, this book is a comprehensive overview of the current state of 5G. Covering everything from the most likely use cases, spectrum aspects, and a wide range of technology options to potential 5G system architectures, it is an indispensable reference for academics and professionals involved in wireless and mobile communications. Global research efforts are summarised, and key component technologies including D2D, mm-wave communications, massive MIMO, coordinated multi-point, wireless network coding, interference management and spectrum issues are described and explained. The significance of 5G for the automotive, building, energy, and manufacturing economic sectors is addressed, as is the relationship between IoT, machine type communications, and cyber-physical systems. This essential resource equips you with a solid insight into the nature, impact and opportunities of 5G.

Increased capacity using CDMA for mobile satellite communication

Abstract: The performance of a spread-spectrum CDMA (code-division multiple access) system in a mobile satellite environment is analyzed. Comparisons to single-channel-per-carrier FDMA systems are presented which show that the CDMA approach provides greater capacity. Results from computer simulations, laboratory tests, and field tests of a prototype modem are also presented. The tests results show excellent performance of the modem in the mobile environment and also the feasibility of the spread-spectrum approach to satellite mobile communications. >

VLC: Beyond point-to-point communication

Abstract: Due to the large growth of mobile communications over the past two decades, cellular systems have resorted to fuller and denser reuse of bandwidth to cope with the growing demand. On one hand, this approach raises the achievable system capacity. On the other hand, however, the increased interference caused by the dense spatial reuse inherently limits the achievable network throughput. Therefore, the spectral efficiency gap between users' demand and network capabilities is ever growing. Most recently, visible light communication has been identified as well equipped to provide additional bandwidth and system capacity without aggregating the interference in the mobile network. Furthermore, energy-efficient indoor lighting and the large amount of indoor traffic can be combined inherently. In this article, VLC is examined as a viable and ready complement to RF indoor communications, and advancement toward future communications. Various application scenarios are discussed, presented with supporting simulation results, and the current technologies and challenges pertaining to VLC implementation are investigated. Finally, an overview of recent VLC commercialization is presented.

Mobile communication system

Abstract: PROBLEM TO BE SOLVED: To provide a mobile communication system in which provision of summary information to a mobile communication terminal can be suppressed, the summary information being improper to be provided thereto, and summary information with a large data size having a possibility of causing entanglement to a mobile communication terminal communication network can be prevented from being transmitted to the mobile communication terminal. SOLUTION: A WEB server 41 attaches identification information (CPID) to identify content providers to an acquisition response (HTTP response) with respect to an acquisition request from the mobile communication terminal 10. A relay server 40 prestores identification information of the content providers for providing summary information (RSS feed) which passes through the relay server and controls passing of the acquisition response on the basis of the identification information in the acquisition response received from the WEB server 41 and the prestored identification information. COPYRIGHT: (C)2008,JPO&INPIT

Vertical Handoff Decision Algorithms for Providing Optimized Performance in Heterogeneous Wireless Networks

Abstract: There are currently a large variety of wireless access networks, including the emerging vehicular ad hoc networks (VANETs). A large variety of applications utilizing these networks will demand features such as real-time, high-availability, and even instantaneous high-bandwidth in some cases. Therefore, it is imperative for network service providers to make the best possible use of the combined resources of available heterogeneous networks (wireless area networks (WLANs), Universal Mobile Telecommunications Systems, VANETs, Worldwide Interoperability for Microwave Access (WiMAX), etc.) for connection support. When connections need to migrate between heterogeneous networks for performance and high-availability reasons, seamless vertical handoff (VHO) is a necessary first step. In the near future, vehicular and other mobile applications will be expected to have seamless VHO between heterogeneous access networks. With regard to VHO performance, there is a critical need to develop algorithms for connection management and optimal resource allocation for seamless mobility. In this paper, we develop a VHO decision algorithm that enables a wireless access network to not only balance the overall load among all attachment points (e.g., base stations and access points) but also maximize the collective battery lifetime of mobile nodes (MNs). In addition, when ad hoc mode is applied to 3/4G wireless data networks, VANETs, and IEEE 802.11 WLANs for a more seamless integration of heterogeneous wireless networks, we devise a route-selection algorithm for forwarding data packets to the most appropriate attachment point to maximize collective battery lifetime and maintain load balancing. Results based on a detailed performance evaluation study are also presented here to demonstrate the efficacy of the proposed algorithms.