Measurements From an 802.11b Mobile Ad Hoc Network [ Source: ETH Zurich ]

January 2008- This paper analyzes the characteristics of a multi-hop 802.11b mobile ad hoc network. The paper presents data gathered from a mobile network of 20 devices carried by test users over 5 days in an indoor environment. The data is investigated with regard to the number of reachable devices, the node degree, the average path length, the link lifetime, and the route lifetime. Despite the relatively high node density and low node mobility in the setup, frequent network ...

Wi-Fi Mobile Convergence: The Role of Wi-Fi CERTIFIED [ Source: Wi-Fi Alliance ]

January 2008- The Wi-Fi Alliance is a strong proponent of Wi-Fi Mobile Convergence (WMC) and has prioritized efforts to make the integration of Wi-Fi and mobile devices easier and to improve the performance of the voice and multimedia applications that are at the core of converged services. The Wi-Fi Alliance manages robust testing and certification programs. This white paper published by Wi-Fi discusses the main drivers behind WMC and role of the Wi-Fi Alliance in promoting WMC ...

Traffic-Aware Routing for Real Time Communications in Wireless Multi-Hop Networks [ Source: Microsoft ]

January 2008- Real time communication (RTC), as one of the most popular applications, has drawn great attention in recent years, especially in wireless multi-hop network which is emerging due to its decentralized nature and the popularity of wireless devices such as Wi-Fi (IEEE 802.11) cards. This paper proposes a novel traffic-aware routing metric for RTC in wireless multi-hop networks. The routing metric, Path Predicted Transmission Time (PPTT), is designed to choose a high-quality path for RTC flow between ...

A High Linearity, High Efficiency WiMAX Power Amplifier Using SiC MESFETs [ Source: Institute of Electrical and Electronics Engineers ]

January 2008- This research paper published by WiMAX describes the results of a broadband, high linearity and high efficiency power amplifier for WiMAX basestation applications in the 3.3 - 3.9 GHz band. Using SiC MESFETs, a single-stage power amplifier has been designed that provides a significant increase in performance, providing 17% drain efficiency, 1.5% EVM, and 3dB margin to spectral mask at 1.5W average output power under a WiMAX compliant signal, compared with realizations using other transistor technologies.

Contention Window Based Parameter Selection to Improve Powerline MAC Efficiency for Large Number of Users [ Source: University of Florida ]

January 2008- Effective use of the power line bandwidth requires robust physical and Medium Access Control (MAC) protocols to mitigate the harsh conditions of the power line channel, as well as the capability to support prioritized multimedia traffic. Just as in 802.11, the throughput performance of this scheme becomes critical when the number of users increases, as in BPL. In this paper, a modification in the medium access control protocol of Home Plug 1.0 is proposed, to make it ...

Service Deployment Architectures for Metro Wi-Fi Networks [ Source: Pronto Networks ]

January 2008- This paper published by Wi-Fi describes about the ways in which mesh networks can incorporate service control and service management platforms to provide these features. The technical aspects of the network that need to be considered in such a best-practices deployment are also described here. Communities are now deploying metro -scale broadband wireless networks for requirements beyond public safety or other internal productivity enhancement applications.

The Complexity of Connectivity in Wireless Networks [ Source: ETH Zurich ]

January 2008- A most important lesson in wireless multi-hop networking is that concurrent transmissions may cause interference. This paper defines and studies the scheduling complexity in wireless networks, which expresses the theoretically achievable efficiency of MAC layer protocols. Given a set of communication requests in arbitrary networks, the scheduling complexity describes the amount of time required to successfully schedule all requests. The most basic and important network structure in wireless networks being connectivity, it studies the scheduling ...

Queueing Delay Analysis of IEEE 802.11e EDCA [ Source: Telenor ]

January 2008- The majority of methodical work on the performance of IEEE 802.11 focuses on predicting the throughput and the mean delay of only the medium access, although higher layer applications and protocols are interested in the total performance. The main contribution of this paper is that it presents the full delay distribution through the z-transform. The z-transform is derived from an analytical model that works in the whole range from a lightly loaded, non-saturated channel to a ...

Wideband Envelope Elimination and Restoration Power Amplifier With High Efficiency Wideband Envelope Amplifier for WLAN 802.11g Applications [ Source: Institute of Electrical and Electronics Engineers ]

January 2008- This paper published by University of California presents the design of a silicon bipolar Class-E WideBand Envelope Elimination and Restoration (WBEER) power amplifier with a wideband high efficiency envelope amplifier. The envelope amplifier is composed of a linear op-amp stage and a switch buck converter, which achieves high fidelity and high efficiency amplification of wideband high Peak to AveRage (PAR) envelope signals.

Wireless Networking Over Extended Range: Technology Options for Optimizing Long Range Wireless Connectivity [ Source: USRobotics ]

January 2008- WiFi, WLAN, 802.11a/b/g are all terms used in the fast growing market of Wireless Networking. WiFi (short for ’Wireless Fidelity’) is the popular term for a high-frequency Wireless Local Area Network (WLAN). High frequency in these terms refers to 2.4GHz (802.11b and g) and 5GHz (802.11a) microwave transmission of WLAN data. This white paper has been compiled using ’Real life’ data collected over the last few years and research from conventional sources of ...

Capacity Evaluation of VoIP in IEEE 802.11e WLAN Environment [ Source: French National Institute for Research in Computer Science and Control ]

January 2008- In this paper, the authors present an analytical model for VoIP capacity in IEEE 802.11e WLAN. Wireless VoIP, typically over 802.11 WLAN, is becoming increasingly popular, but even further elevates the challenges of delay and loss reduction. Degradation of speech quality caused by packet delay and loss of voice traffic is still one of critical technical barriers of the VoIP system. Furthermore, apart from these limitations WLANs will need to support a large number of concurrent ...

Step-by-Step Secure Wireless for Home / Small Office and Small Organizations [ Source: Microsoft ]

January 2008- This white paper from Microsoft presents two deployment methods for secure wireless access: one for Small Office/Home Office (SOHO) networks and one for small organizations. For SOHO networks, this paper describes how to configure secure wireless access for computers running Microsoft Windows XP with Service Pack 2 (SP2) and other wireless devices. If one is planning a new network with wireless access or if one is considering a change to a different type of network ...

Overview of the WPA Wireless Security Update in Windows XP [ Source: Microsoft ]

January 2008- This paper from Microsoft discusses the new Wi-Fi Protected Access (WPA) update in Microsoft Windows XP. The Institute of Electrical & Electronics Engineers (IEEE) 802.11i wireless networking standard specifies improvements to wireless Local Area Networking (LAN) security. The 802.11i standard is currently in draft form, with ratification due at the end of 2003. The new IEEE 802.11i standard is being ratified, wireless vendors have agreed on an interoperable interim standard known as Wi-Fi Protected Access (WPA).