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 TitleDate AddedCompany
whitepaper Location-Based Services for Cellular Phones Using Wi-Fi: The University of Cincinnati's System for Emergency Call Location2009-09-01 Aruba Networks
  Virtually every new smartphone coming to market now has Wi-Fi functionality, and Wi-Fi is preferred for data services due to its high performance and low cost. Many universities already offer Wi-Fi in lecture theaters, cafes and residence halls, and are now expanding their WLANs to cover their entire campus. This paper describes a novel system developed by the University of Cincinnati which enables on-campus location-based services for conventional voice calls from cell phones by recognizing and locating the Wi-Fi signal associated with the handset via the campus WLAN.

Tags: Mobile and Wireless, Mobile and Wireless		   
whitepaper 802.11 Arbitration2009-09-01 CWNP
  This whitepaper is intended to provide a thorough exploration of the channel access methods used in IEEE 802.11 WLANs. While the 802.11 standard specifies multiple subsets of functionality, not all of them are currently used in today's WLANs; therefore, this paper will address, in detail, only those mechanisms currently used in DCF and HCF implementations. Because the topic of 802.11 arbitration is multifaceted and often very confusing, this paper will attempt to explain these mechanisms in detail, dissecting the many components included in 802.11 channel accesses. Some details have been intentionally excluded due to the overwhelming depth of this material. After examining the details, this paper also provide a brief discussion of the applications and significance of understanding these functions as a WLAN professional.

Tags: Mobile and Wireless		   
whitepaper A SDR Platform for Mobile Wi-Fi/3G UMTS System on a Dynamic Reconfigurable Architecture2009-08-28 EURASIP
  As wireless communication standards evolve, Wi-Fi and WCDMA based 3G UMTS are still the major technologies widely deployed to provide high speed wireless internet access and mobile communication services. Therefore, the integration of these two protocols onto a single SDR platform is a major research task. This paper proposes a flexible SDR platform targeting the above standards. The SDR platform is based on a recently developed novel Reconfigurable Instruction Cell Array (RICA) along with an ARM controller. The paper describes the proposed platform architecture, the associated software design flow, and the mapping methodology.

Tags: Mobile and Wireless		   
whitepaper Performance Analysis of IEEE 802.11n Under Different STBC Rates Using 64-QAM2009-08-27 Institute of Electrical and Electronics Engineers
  The main focus of current research and development for the next-generation Wireless Local Area Network (WLAN) communication systems is to enhance the link throughput and channel capacity. In this paper, the performance analysis of the ongoing next-generation WLAN standard, IEEE 802.11n high throughput WLAN PHY layer is presented. The design criteria is based on a 4x4 MIMO-OFDM scheme using 64-QAM (Quadrature Amplitude Modulation) technique under Rayleigh frequency-selective fading and flat fading channels. Simulation results show that a significant performance gain, 4~7 dB, depending on the channel selection, can be achieved when 1/2 Space-Time Block Code (STBC) rate is applied with respect to Bit-Error-Rate (BER).

Tags: Software Development Tools, Mobile and Wireless		   
whitepaper Link-Level Measurements of Outdoor 802.11g Links2009-08-25 Institute of Electrical and Electronics Engineers
  802.11 based outdoor community mesh networks have seen several deployments in the last few years. Prior link level studies focus mostly on 802.11b links, and a systematic and detailed link-level study of 802.11g is lacking. This paper presents a study of the link error rate as a function of the RSSI; it closely examines the RSSI threshold beyond which the link error rate is negligible. Its study is based on a wireless network testbed established in IIT Bombay. The testbed has nine nodes with links varying from 90 m to 1.2 km. It finds that the link abstraction holds in the case of 802.11g and RSSI threshold range can be used for the predictable performance for such links.

Tags: Mobile and Wireless		   
whitepaper White Space Networking With Wi-Fi Like Connectivity2009-08-21 Association for Computing Machinery
  Networking over UHF white spaces is fundamentally different from conventional Wi-Fi along three axes: spatial variation, temporal variation, and fragmentation of the UHF spectrum. Each of these differences gives rise to new challenges for implementing a wireless network in this band. The paper presents the design and implementation of WhiteFi, the first Wi-Fi like system constructed on top of UHF white spaces. WhiteFi incorporates a new adaptive spectrum assignment algorithm to handle spectrum variation and fragmentation, and proposes a low overhead protocol to handle temporal variation. WhiteFi builds on a simple technique, called SIFT, that reduces the time to detect transmissions in variable channel width systems by analyzing raw signals in the time domain.

Tags: Mobile and Wireless		   
whitepaper Energy-Efficient Network Selection With Mobility Pattern Awareness in an Integrated WiMAX and WiFi Network2009-08-12 John Wiley & Sons
  To provide wireless Internet access, WiFi networks have been deployed in many regions such as buildings and campuses. However, WiFi networks are still insufficient to support ubiquitous wireless service due to their narrow coverage. One possibility to resolve this deficiency is to integrate WiFi networks with the wide-range WiMAX networks. Under such an integrated WiMAX and WiFi network, how to conduct energy-efficient handovers is a critical issue. This paper proposes a Handover scheme with Geographic Mobility Awareness (HGMA), which considers the historical handover patterns of mobile devices. HGMA can conserve the energy of handovering devices from three aspects.

Tags: Mobile and Wireless, Mobile and Wireless		   
whitepaper MAC-Aware Routing Metric for 802.11 Wireless Mesh Networks2009-08-11 Seoul National University
  It developed a new wireless link quality metric, ECOT (Estimated Channel Occupancy Time) that enables a high throughput route setup in wireless mesh networks. The key feature of ECOT is being applicable to diverse mesh network environments where IEEE 802.11 MAC (Medium Access Control) variants are used. It takes into account the detailed operational features of various 802.11 MAC protocols, such as 802.11 DCF (Distributed Coordination Function), 802.11e EDCA (Enhanced Distributed Channel Access) with BACK (Block Acknowledgment), and 802.11n A-MPDU (Aggregate MAC Protocol Data Unit), and derive an integrated link metric that enables finding maximum throughput end-to-end routes.

Tags: Software Development Tools, Mobile and Wireless		   
whitepaper Enhancement Throughput of Unplanned Wireless Mesh Networks Deployment Using Partitioning Hierarchical Cluster (PHC)2009-08-09 University of Malaya
  Wireless mesh networks based on IEEE 802.11 technology are a scalable and efficient solution for next generation wireless networking to provide wide-area wideband internet access to a significant number of users. The deployment of these wireless mesh networks may be within different authorities and without any planning, they are potentially overlapped partially or completely in the same service area. The aim of the proposed model is design a new model to Enhancement Throughput of Unplanned Wireless Mesh Networks Deployment Using Partitioning Hierarchical Cluster (PHC), the unplanned deployment of WMNs are determinates there performance.

Tags: Mobile and Wireless		   
whitepaper Playout Buffer and Rate Optimization for Streaming Over IEEE 802.11 Wireless Networks2009-08-01 Association for Computing Machinery
  Most streaming rate selection and buffer optimization algorithms are developed for wired networks and can perform poorly over wireless networks. WirelessMAClayer behavior, such as rate adaptation, retransmissions, and medium sharing, can significantly degrade the effectiveness of current streaming algorithms. This paper presents the Buffer and Rate Optimization for Streaming (BROS) algorithm to improve streaming performance. BROS uses a bandwidth estimation tool designed specifically for wireless networks and models the relationship between buffer size, streaming data rate, and available bandwidth distribution. BROS optimizes the streaming data rate and initial buffer size, resulting in a high data rate but with few frame losses and buffer underflow events, while still keeping a small initial buffer delay.

Tags: Mobile and Wireless