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 TitleDate AddedCompany
whitepaper Enterprise-Wide Compliance with System Center Configuration Manager 20072009-02-25 Quest Software
  Microsoft's System Center Configuration Manager 2007 (Configuration Manager) is a powerful ally when you need to achieve, maintain and prove compliance. However, its primary focus is systems running Microsoft Windows. In today's diverse IT environment, how can Configuration Manager help with change, configuration and system updating across all of your Windows and non-Windows systems?

In this new white paper, learn how you can extend Configuration Manager's capabilities to non-windows systems. See how doing so makes Configuration Manager perfect for helping ensure governance, risk management and compliance strategies are obtained in your organization. Read it today.

Tags: IT Infrastructure, Mobile and Wireless, Mobile and Wireless, Handhelds, Server Platforms - OS, Server Platforms - OS, User Satisfaction, Server Platforms - OS		   
whitepaper 3G Coming to Ukraine2009-01-01
  The 3G family of standards such as WCDMA or UMTS has been developed by International Telecommunication Union (ITU), and is otherwise called International Mobile Telecommunications 2000 (IMT-2000). It covers 5 smaller standards, namely: WCDMA, CDMA2000, TD-CDMA/TD-SCDMA, DECT and UWC-136. According to the IMT-2000 standard, the 3rd generation mobile connection should be provided in an integrated network capable of data transfer: not less than 144 Kbps for highly mobile users (up to 75 miles per hour), 384 Kbps for low mobile users (up to 1.8 mile per hour), and 2.048 Mbps for immobile users within short distances.

Tags: Mobile and Wireless		   
whitepaper Optimization of Hybrid Token-CDMA MAC System Using Cross-Layer Information2009-01-01 Institute of Electrical and Electronics Engineers
  This paper presents a joint Medium Access Control and PHYsical (MAC-PHY) layers solution for optimizing the system performance in the hybrid Token-CDMA MAC system. The proposed scheme is designed in order to provide continuous monitoring of the performance achieved by the users and adjusting transmission parameters using different spreading factors. Various performance metrics are used to demonstrate effectiveness of the cross-layer interaction for the hybrid Token-CDMA MAC protocol.

Tags: Mobile and Wireless, Mobile and Wireless		   
whitepaper Bounds on the Sum Capacity of Synchronous Binary CDMA Channels2008-12-30 Sharif University of Technology
  This paper obtains a family of lower bounds for the sum capacity of Code Division Multiple Access (CDMA) channels assuming binary inputs and binary signature codes in the presence of additive i.i.d. noise with an arbitrary distribution. The envelope of this family gives a relatively tight lower bound in terms of the number of users, spreading gain and the noise distribution. The derivation methods for the noiseless and the noisy channels are different but when the noise variance goes to zero, the noisy channel bound approaches the noiseless case. The behavior of the lower bound shows that for small noise power, the number of users can be much more than the spreading gain without any significant loss of information (overloaded CDMA).

Tags: Mobile and Wireless		   
whitepaper Novel Tap-Wise LMMSE Channel Estimation for MIMO W-CDMA2008-12-09 Institute of Electrical and Electronics Engineers
  In this paper, a tap-wise LMMSE channel estimator for MIMO W-CDMA is derived. Descrambling operations applied to delayed versions of the received signal whiten the input signal. The descrambling process thus breaks up the full channel autocorrelation matrix (including spatial and temporal correlation) into several independent, small autocorrelation matrices that include only spatial correlation. The problem of estimating the channel autocorrelation matrices is tackled by an "Instantaneous" autocorrelation estimator that uses only one channel estimate (obtained by a very low complexity channel estimator) as input. Simulation results of a MIMO HSDPA system show that the tap-wise LMMSE estimator with instantaneous channel autocorrelation estimation yields performance gains of up to 0.85 dB over a correlation-based channel estimator.

Tags: Mobile and Wireless		   
whitepaper Performance of Multicarrier DS-CDMA Systems Using Chaotic Spreading Codes With Arbitrary Carrier Spacing2008-10-01
  The MultiCarrier (MC) Direct-Sequence (DS) Code Division Multiple Access (CDMA) system employing chaotic spreading sequences is considered in this paper. Firstly, the Multiple Access Interference (MAI) of the MC DS-CDMA system using chaotic spreading sequences with arbitrary amount of carrier spacing is theoretically analyzed. The investigation of optimum parameters of autocorrelation together with the optimum spacing between subcarriers is carried out in order to minimize the MAI. The average Bit Error Probability (BEP) derived from the resultant minimized MAI is compared with that for conventional independent and identically distributed (i.i.d.) binary sequences. Numerical examples show the superiority of chaotic spreading sequences to i.i.d. codes in terms of the average BEP.

Tags: Mobile and Wireless, Mobile and Wireless		   
whitepaper Cell Site Power Characterization for Multi-Rate Wireless CDMA Data Networks Using Lognormal Approximation2008-10-01 Academy Publisher
  An analytical model is developed to solve the power-rate assignment problem for multi-rate CDMA systems and calculate the Probability Density Function (PDF) for the downlink traffic power as a function of the bit rate assignment scheme, the target link quality figure, and the other network parameters. This paper proposes the use of the lognormal random variable as an approximation for an empirical parameter (denoted herein by fi) that is needed to solve the energy per-bit to noise spectral power density equation for scheduled data bursts.

Tags: Mobile and Wireless, Mobile and Wireless		   
whitepaper Experimental Triple-Play Service Delivery Using Commodity Wireless LAN Hardware2008-09-04 University of Western Ontario
  This paper studies the feasibility of utilizing Wireless Local Area Network (WLAN) technology to deliver the Triple-Play services (video, voice and data) over a specific system model. Existing protocols are shown to not efficiently manage the wireless channel therefore one proposes a new Triple-Play Time Division Multiple Access (TP-TDMA) Media Access Control (MAC) protocol to provide Quality of Service (QoS) for these Triple-Play services in a point-to-multipoint network over an existing 802.11a physical layer. Through extensive simulation analysis, the protocol is shown to offer better performance than the 802.11e Enhanced Distributed Coordination Function (EDCF). Moreover, this protocol is implemented in hardware using the MADWiFi driver to verify the real-world performance. Both results of the simulation study and hardware implementation are provided.

Tags: Mobile and Wireless, Mobile and Wireless		   
whitepaper Optimal Scheduling and Power Control for TDMA Based Point to Multipoint Wireless Networks2008-08-18 Association for Computing Machinery
  In TDMA-based point-to-multipoint rural wireless deployments, co-located base station radios and sector antennas are used to increase base station capacity. To achieve maximum capacity with limited availability of non-overlapping wireless channels, as many radios as possible are need to operate from different sectors on the same channel. However, operating co-located radios on the same channel can result in substantial interference especially with the current practice of operating all radios at maximum power. This paper investigates techniques that increase network throughput by eliminating this interference.

Tags: Mobile and Wireless		   
whitepaper CDMA and OFDM: The Convergence of Wireless Broadband Services2008-07-31 10:00:37 CDMA Development Group (CDG)
  The “one technology fits all” approach will not suffice in the future competitive telecommunications market. Operators will leverage the most appropriate technology for a particular application or service. In most instances, 3G CDMA will remain the leading and most economical platform for the delivery of mobile broadband services.