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 TitleDate AddedCompany
whitepaper Enhance Customer Loyalty through Higher Responsiveness2009-04-01 Oracle
  The economic downturn is forcing businesses to tighten their belts and look for more efficient channels. Using the Internet as a business channel, and sometimes even the only channel, is becoming more prevalent. However, there are significant challenges to being successful at e-commerce. The user experience associated with web applications relies in large part on the availability and management of their session data, its persistence, and its management. This white paper focuses on the topic of data availability and management for mission-critical web applications.

Tags: Business Functions, IT Budgeting		   
whitepaper RS-232: A Key To Understanding Data Communications2008-07-22 Global Knowledge
  Experts have been predicting the death of the RS-232 interface for decades, and yet it continues to serve us well. It is a highly proven technology that is inexpensive and easy to implement. And it is well-understood and widely accepted in IT and related endeavors. This white paper provides some of the history of RS-232, and its usefulness today.

Tags: IT Infrastructure, Components, Components, Staff Training		   
whitepaper Extended Loops for Distant Phones and Fax Machines, Higher Ringing Voltage and Loop Current2008-04-01 Cisco Systems
  Enterprises are turning to Voice-over-IP (VoIP) and IP telephony solutions for voice communications in corporate and branches so that they can reap the benefits of converged networks and feature-rich IP-based telephone systems. While enterprises are making the migration to IP telephony, on many occasions legacy analog phones, modems, and fax machines continue to be important and vital components in the network. Applications exist that require extended loops between the analog phones and the gateway. Examples include phones in multi-story buildings, on large campuses, in large railroad yards, in large industrial plants, and in remote locations such as utilities applications. Other applications require accommodations for specialty phones, including elevator phones, emergency kiosk phones, and neon-lamp phones.

Tags: Components, Office Equipment		   
whitepaper Advanced PHY Layer Technologies for High Speed Data Over Cable2007-01-04 Cisco Systems
  This paper highlights the major differences between DOCSIS 2.0 and earlier versions, and discusses advantages of deploying the advanced PHY technology available nowadays. This paper summarizes numerous field and lab tests that demonstrate how Cable Modem Termination Systems (CMTSs) and cable modems using advanced PHY silicon perform in the presence of impairments. Also discussed is the fact that a number of advanced PHY features benefit existing DOCSIS 1.0 and 1.1 cable modems. Many advanced PHY functions - for instance, ingress cancellation - occur in the CMTS and are modem agnostic. That means it is not necessary to replace older modems with new DOCSIS 2.0 modems to reap some of the benefits of advanced PHY.

Tags: Network Technologies		   
whitepaper Upstream FEC Errors and SNR as Ways to Ensure Data Quality and Throughput2005-09-30 Cisco Systems
  To operate a High Speed Data (HSD) network over a Hybrid Fiber/Coaxial (HFC) cable plant requires a significant level of quality control to ensure data integrity and the highest level of data throughput. The two generally accepted means by which cable operators can measure data quality is by monitoring either the Bit Error Rate (BER) or the Packet Error Rate (PER). The Data Over Cable Service Interface Specification (DOCSIS) outlines requirements that each cable operator must maintain in order to reliably transport IP data traffic. An important feature of DOCSIS addresses the need to protect IP data against Radio Frequency (RF) noise impairments. The feature DOCSIS uses to help maintain IP data integrity over HFC cable plants is Reed-Solomon Forward Error Correction (FEC) encoding.

Tags: Components, Network Technologies		   
whitepaper Adaptive OFDM Synchronization Algorithms Based on Discrete Stochastic Approximation2004-03-02 University of New Brunswick
  This paper presents discrete stochastic approximation algorithms (DSA) for time synchronization in OFDM systems. The paper shows that the discrete stochastic approximation algorithms can be effectively used to achieve a significant reduction in computational complexity compared to brute force maximum-likelihood (ML) methods for OFDM synchronization. The most important property of the proposed algorithms is their recursive self-learning capability - most of the computational effort is spent at the global or a local optimizer of the objective function.

Tags: Mobile and Wireless, Components, 		  
whitepaper Cross-Layer Optimization for Scheduling in OFDM-TDMA Transmission2004-10-15 ETH Zurich
  In the integrated project My personal Adaptive Global NET (MAGNET) of the European Union, advanced adaptive and scalable air interface concepts for personal area networks (PANs) are being studied. The activities are grouped in clusters dealing with different data rates in the physical layer. This paper gives an overview of some initial activities in the air interface design considered in the orthogonal frequency-division multiplexing (OFDM) time-division multiple access (TDMA) cluster.

Tags: Components, Mobile and Wireless		   
whitepaper Pilot-to-Data Power Ratio for Maximizing the Capacity of MIMO-OFDM2004-11-22 Institute of Electrical and Electronics Engineers
  Orthogonal frequency division multiplexing (OFDM) can be used with a multiple-input multiple-output (MIMO) system to improve communication quality and capacity. Pilot-symbol-aided or decision-directed channel estimation must be used to track the variations of the channel. However, while pilot symbols facilitate channel estimation, they reduce the transmit energy for data symbols per OFDM symbol under a fixed total transmit power constraint. This paper analyzes the effects of pilot-symbol-aided channel estimation on the lower bound of the system capacity in MIMO-OFDM systems with three different types of pilot patterns: independent, scattered, and orthogonal.

Tags: Mobile and Wireless, Components, 		  
whitepaper Multiuser Interference Cancellation for OFDM Systems With Frequency Offset2003-07-15 University of Florence
  This paper proposes a method to counteract the effect of different frequency offsets of the users in a OFDMA uplink system with frequency selective Rayleigh fading channel. The multiple access interference is reduced by reconstructing and removing the interfering signals. This is done by accomplish Successive or Selective Cancellation. The paper analyzes the performance of these cancellation schemes assuming either ideal or estimated frequency offsets.

Tags: Components, Mobile and Wireless		   
whitepaper UWB Coexistence and Cognitive Radio: How Multiband-OFDM Leads the Way2004-09-15 Alereon
  The recent history of Ultrawideband communications technology has seen great debate over whether these UWB cause unacceptable interference to existing users of the same and nearby bands. Building on the IEEE 802.15.2 Recommended Practice and the framework developed by IEEE 802.19, researchers are developing techniques to separate UWB signals for others using time, frequency, power, space, and coding, the five techniques available to minimize interference and maximize capacity. This paper explores general methods for using these parameters either to eliminate interference, or to achieve graceful, deterministic degradation.

Tags: Mobile and Wireless, Mobile and Wireless