Introduction to cdma2000 Standards for Spread
Spectrum Systems


OVERVIEW

The cdma2000 Family of Standards
The cdma2000 family of standards includes core air interface, minimum performance, and
service standards (see 1.3). The cdma2000 air interface standards specify a spread
spectrum radio interface that uses Code Division Multiple Access (CDMA) technology to
meet the requirements for Third Generation (3G) wireless communication systems. The
core air interface standards in the family are [ ....etc

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i want ppt of differnce between optical &electrical bandwidth.
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This uses a novel method of speech compression and transmission. This method saves the transmission bandwidth required for the speech signal by a considerable amount. This scheme exploits the property of low pass nature of the speech signal. Also this method applies equally well for any signal, which is low pass in nature, speech being the more widely used in Real Time Communication, is highlighted here.

As per this method, the low pass signal (speech) at the transmitter is divided into set of packets, each containing, say N number of sample ....etc

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Abstract: In this paper, we propose an accurate method to evaluate the available bandwidth in IEEE 802.11-based ad hoc networks. We improve the method described in. We evaluate our solution on di_erent scenarios. We also provide a comparison with different QoS routing protocols, BRuIT, AAC and QoS-AODV, based on di_erent available bandwidth estimation techniques.
Presented By:
Cheikh Sarr ”Claude Chaudet ” Guillaume Chelius ” Isabelle Guérin Lassous
Introduction
The quality of service issues in ad hoc n ....etc

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Differentiated Bandwidth Allocation with TCP Protection in Core Routers


Abstract

Differentiated Services (DiffServ) networks categorize routers into edge routers and core routers.In core routers, one of the technological challenges is how to implement differentiated bandwidth allocation and TCP protection together with low complexity.We present an Active Queue Management (AQM) scheme called CHOKeW. A method is borrowed from a previous scheme, CHOKe, which draws a packet at random from the buffer, compares it with the arriving packet, a ....etc

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BANDWIDTH ESTIMATION FOR IEEE 802.11 BASED ADHOC NETWORK-MOBILE COMPUTING

Abstract: Since 2005, IEEE 802.11-based networks have been able to provide a certain level of quality of service (QoS) by the means of service differentiation, due to the IEEE 802.11e amendment. However, no mechanism or method has been standardized to accurately evaluate the amount of resources remaining on a given channel. Such an evaluation would, however, be a good asset for bandwidth-constrained applications. In multihop ad hoc networks, such evaluation becomes ev ....etc

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Abstract:
IEEE is currently standardizing a new high-speed backbone technology for MANs--Resilient Packet Ring (RPR). A key performance objective of RPR is to achieve high utilization, spatial reuse, and fairness simultaneously. However, the algorithms proposed in current draft standards have some critical limitations. As shown in unbalanced traffic scenario, drafts RPR algorithm will suffer from dramatic bandwidth oscillations within nearly the entire range of the page link capacity. In this paper, we propose a new dynamic ....etc

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BANDWIDTH ESTIMATION FOR IEEE 802.11 BASED ADHOC NETWORK
Abstract: Since 2005, IEEE 802.11-based networks have been able to provide a certain level of quality of service (QoS) by the means of service differentiation, due to the IEEE 802.11e amendment. However, no mechanism or method has been standardized to accurately evaluate the amount of resources remaining on a given channel. Such an evaluation would, however, be a good asset for bandwidth-constrained applications. In multihop ad hoc networks, such evaluation becomes even more difficult. C ....etc

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CDMA2000 is a technology for the development of cdmaOne/IS-95 to 3rd generation services. Also known as IMT-CDMA Multi-Carrier or IS-2000 is the main route for CDMA operators to second-and-a-half ( 2.5G) and third generation (3G) cellular networks. A set of new standards that define the new air interface and the Radio Access and Core Network changes that will enhance network capacity, improve speed and bandwidth to mobile terminals, and allow end-to-end IP services has been created by the standard-setting body behind CDMA2000 known as 3GPP2. C ....etc

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Presented by:
Rodger E. Ziemer


3G CDMA - WCDMA and cdma2000
Rules for Efficient Multiple Access
Three laws
 Know the channel
 Minimize interference to others
 Mitigate interference received from others
 Requirements of wireless multiple access
 Channel measurement
 Channel control and modification
 Multiple user channel isolation
Why CDMA?
 Higher capacity
 Improved performance in multipath by diversity
 Lower mobile transmit power = longer battery life
 ....etc

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