Building to Building Communication using Zigbee(IEEE802.15.4) Standard

The present technologies Bluetooth and Wi-Fi are basically used for local short range voice communication. Bluetooth technology can be used to communicate between the two android end devices without any hops but it limits the communication range in orders of meters. Wi-Fi can overcome the above problem but it is power hungry as the android devices discharge power very fast. To address the above problems, we proposed an optimum solution using the zigbee (IEEE 802.15.4) technology. In our approach we design and build a self-powered wireless chipset which is interfaced to the android mobile using serial port and the network is established with the chipsets as relays

Proceedings of the Mobile Satellite Conference

A satellite-based mobile communications system provides voice and data communications to mobile users over a vast geographic area. The technical and service characteristics of mobile satellite systems (MSSs) are presented and form an in-depth view of the current MSS status at the system and subsystem levels. Major emphasis is placed on developments, current and future, in the following critical MSS technology areas: vehicle antennas, networking, modulation and coding, speech compression, channel characterization, space segment technology and MSS experiments. Also, the mobile satellite communications needs of government agencies are addressed, as is the MSS potential to fulfill them

The design and application of power line carrier communication and remote meter reading for use in integrated services and broadband - integrated services digital networks

SIGLEAvailable from British Library Document Supply Centre-DSC:DXN009939 / BLDSC - British Library Document Supply CentreGBUnited Kingdo

Multi-carrier CDMA using convolutional coding and interference cancellation

SIGLEAvailable from British Library Document Supply Centre-DSC:DXN016251 / BLDSC - British Library Document Supply CentreGBUnited Kingdo

Building China's high-tech telecom equipment industry : a study of strategies in technology acquisition for competitive advantage

Thesis (M.C.P.)--Massachusetts Institute of Technology, Dept. of Urban Studies and Planning; and, (S.M.)--Massachusetts Institute of Technology, Technology and Policy Program, 2001.Includes bibliographical references (p. 171-175).Over the past decade, China has witnessed a rapid growth in its information and communications technology (ICT) sector. The subject of this thesis specifically focuses on the telecommunications infrastructure equipment industry in China. This sector is an interesting one to study given that some of the leading domestic companies have mostly emphasized developing their own capabilities in product development, rather than calling upon formal technology transfers through foreign direct investment (FDI) initiatives. A significant challenge faced by local firms, however, is that foreign equipment manufacturers possessing deeper technological resources dominate their domestic market. Nevertheless, Chinese enterprises have recently begun producing high-end equipment such as core/backbone routers and DWDM optical transmission systems. The basic question this thesis seeks to answer, therefore, is how can Chinese companies become technologically competitive within the high-end segments of the telecom equipment market? A case study methodology was used to address this question, focusing on two leading domestic firms: Huawei Technologies, a privately owned company, and ZTE Corporation (Zhongxing), a state-owned enterprise. The findings show that four factors have contributed to the competitiveness of domestic firms. Firstly, they are able to successfully leverage the configurational nature of communications technology. Secondly, the substantial investment made by the case study firms to develop their own R&D capabilities has enabled them to become 'close followers' of the world technological frontier. Thirdly, the global trend towards a less vertically integrated equipment industry has produced a base of suppliers from which Chinese firms can procure world-class component and subsystem technologies. Lastly, the role of the Chinese government has been instrumental in building technological capabilities at the national level and expanding market demand. Reciprocal arrangements and performance requirements established between government and domestic firms have encouraged the latter to upgrade their technological capabilities. These combined observations provide a perspective on firm competitiveness in high tech industries that is somewhat different to the models proposed under 'second mover advantage' theory. Furthermore, the analyses made of technology acquisition at the level of the firm highlight the importance of independent development (where possible), compared to FDI, as a vehicle for technological development within late industrializing economies.by Aleyn Smith-Gillespie.S.M.M.C.P

Load balancing in heterogeneous wireless communications networks. Optimized load aware vertical handovers in satellite-terrestrial hybrid networks incorporating IEEE 802.21 media independent handover and cognitive algorithms.

Heterogeneous wireless networking technologies such as satellite, UMTS, WiMax and WLAN are being used to provide network access for both voice and data services. In big cities, the densely populated areas like town centres, shopping centres and train stations may have coverage of multiple wireless networks. Traditional Radio Access Technology (RAT) selection algorithms are mainly based on the ¿Always Best Connected¿ paradigm whereby the mobile nodes are always directed towards the available network which has the strongest and fastest link. Hence a large number of mobile users may be connected to the more common UMTS while the other networks like WiMax and WLAN would be underutilised, thereby creating an unbalanced load across these different wireless networks. This high variation among the load across different co-located networks may cause congestion on overloaded network leading to high call blocking and call dropping probabilities. This can be alleviated by moving mobile users from heavily loaded networks to least loaded networks. This thesis presents a novel framework for load balancing in heterogeneous wireless networks incorporating the IEEE 802.21 Media Independent Handover (MIH). The framework comprises of novel load-aware RAT selection techniques and novel network load balancing mechanism. Three new different load balancing algorithms i.e. baseline, fuzzy and neural-fuzzy algorithms have also been presented in this thesis that are used by the framework for efficient load balancing across the different co-located wireless networks. A simulation model developed in NS2 validates the performance of the proposed load balancing framework. Different attributes like load distribution in all wireless networks, handover latencies, packet drops, throughput at mobile nodes and network utilization have been observed to evaluate the effects of load balancing using different scenarios. The simulation results indicate that with load balancing the performance efficiency improves as the overloaded situation is avoided by load balancing

Abstracts on Radio Direction Finding (1899 - 1995)

The files on this record represent the various databases that originally composed the CD-ROM issue of "Abstracts on Radio Direction Finding" database, which is now part of the Dudley Knox Library's Abstracts and Selected Full Text Documents on Radio Direction Finding (1899 - 1995) Collection. (See Calhoun record https://calhoun.nps.edu/handle/10945/57364 for further information on this collection and the bibliography). Due to issues of technological obsolescence preventing current and future audiences from accessing the bibliography, DKL exported and converted into the three files on this record the various databases contained in the CD-ROM. The contents of these files are: 1) RDFA_CompleteBibliography_xls.zip [RDFA_CompleteBibliography.xls: Metadata for the complete bibliography, in Excel 97-2003 Workbook format; RDFA_Glossary.xls: Glossary of terms, in Excel 97-2003 Workbookformat; RDFA_Biographies.xls: Biographies of leading figures, in Excel 97-2003 Workbook format]; 2) RDFA_CompleteBibliography_csv.zip [RDFA_CompleteBibliography.TXT: Metadata for the complete bibliography, in CSV format; RDFA_Glossary.TXT: Glossary of terms, in CSV format; RDFA_Biographies.TXT: Biographies of leading figures, in CSV format]; 3) RDFA_CompleteBibliography.pdf: A human readable display of the bibliographic data, as a means of double-checking any possible deviations due to conversion

Optimisation of automatic train protection systems.

EThOS - Electronic Theses Online ServiceGBUnited Kingdo