Cdma benefits increased voice capacity by several times provided more efficient use of spectrum resources increased battery life in mobile devices better security with cdma encoding cdma is the foundation for mobile 3g technologies potential voice capacity improvements1 reference 1x 3x 14x analog 1980s gsm 1990s cdmaone 1990s. The system will communicate serially to an rf frontend called the usrp. Mobile, one decade for a leap gsm, cdma amps tacs wcdma cdma2000 tdscdma wimax lte ltea 4. Using microsoft powerpoint or office 365, you can easily create engaging presentations. These arent the permissions youre looking for anthony lineberry david luke richardson tim wyatt defcon 18. Theyre in powerpoint form so you can add, modify, and delete slides including this one and slide content to suit your needs.
Is95 cdma receiver, international symposium on low power electro nics and design, 1999. Many conversations are multiplexed into a single channel. Studies have shown that 50% of the time there is no speech signal. Share them with others and work together at the same time.
A free powerpoint ppt presentation displayed as a flash slide show on id. Is95 cdma radio aspects is95 is an air interface standard only system use fddfdma cdma fdd uplink and downlink channels separated according to cellular band or pcs band regulatory requirements fdma breaks up licensed spectrum into 1. In cdma, every channel uses the full available spectrum. Slides is a place for creating, presenting and sharing presentations. To save the current slide only as a pdf, under range, select current slide. Prepared by ibrahim alobida 816 code division multiple access cdma cdma features. Fundamentals of communications access technologies.
References in this presentation to qualcomm may mean qualcomm incorporated, qualcomm technologies, inc. Introduction to cdma code division multiple access cdma is a radically new concept in wireless communications. Aug 14, 2015 at present, cdma commercial networks areat present, cdma commercial networks are established in about 40 countries or area, almostestablished in about 40 countries or area, almost 20% of all users in the world20% of all users in the world 4. When someone is editing your presentation, you can see their cursor as. Dsss and fhss physical layer options have been designed specifically to overcome the interfering with other devices in this band.
Gsm technology was developed by europe in1982 but its massive deployment started in 1992. In normal view, on the slide with the pdf file, click the pdf file s icon or image, and then on the insert tab, in the links group, click action. This deck will briefly guide you through the new pro feature. Code division multiple access technologies based on cdma. Using a large number of parallel narrowband subcarriers instead of a single wideband carrier to transport information ladvantages.
Download the ppt file and save it to your computer. The ds code is a signal generated by linear modulation with. Were making these slides freely available to all faculty, students, readers. In the next time interval, it transmits using the second frequency. Executive summary cdma stands for code division multiple access. Leading the world to 5g mobile technology qualcomm. Systems fplmts 1997 changed to imt2000 international mobile telecom. In the first time slot, a given user transmit to the base station using the first frequency in its frequency hopping sequence. Our pdf to powerpoint converter will turn your pdf into ppt in seconds. In this project we will use c language to design a multicarrier cdma com. A gsm jammer or cell phone jammer is a device that transmit signal on the same frequency at which the gsm system operates, the jamsming success when the mobile phones in the area where the jammer is located are disabled. Code division multiple access for wireless communications prof. Whether in shipping and receiving, or in cdma, packaging is extremely important. Ee4512 analog and digital communications chapter 7 time division multiplexing tdm combines several low, fixed and predefined bit rate sources into a single high speed bit stream for transmission over a single digital.
Blind multiuser data estimation in asynchronous and unequal power dsss systems without any prior knowledge of spreading sequences, sarnof09, march 30 april 1 2009, princeton, nj. This helps you give your presentation on 3g vs wifi in a conference, a school lecture, a business proposal, in a webinar and business and professional representations. Cdma consistently provides better capacity for voice and data communications than other commercial mobile technologies, allowing more subscribers to connect at any given time, and it is the common platform on which 3g technologies are built. Introduction to ofdm lbasic idea using a large number of parallel narrowband subcarriers instead of a single wideband carrier to transport information ladvantages very easy and efficient in dealing with multipath robust again narrowband interference ldisadvantages sensitive to frequency offset and phase noise. This presentation by rishi mohindra adaptive rf, inc analyzes a cdma. Imagine if only one person could talk on their cell phone at a time. Code division multiple access cdma the coding and modulation process in cdma. Code division multiple access cdma i the cdma standard was originally designed by qualcomm in the u. In the insert object box, select create from file, and then enter the pdf file location. In 2000, gsm become very popular technology worldwide. Insert pdf file content into a powerpoint presentation. Increased body temperature in gsm and cdmaexposed rats 6 and 9 wkg gsm dams during gestation and lactation 9 wkg cdma dams during late gestation and throughout lactation at several time points during gestation and lactation, body temperatures observed at 9 wkg exceeded controls by 1.
Chapter 7 multiple division techniques outline frequency division multiple access fdma time division multiple access tdma code division multiple access cdma comparison of fdma, tdma, and cdma walsh codes nearfar problem types of interferences analog and digital signals basic modulation techniques amplitude modulation am frequency modulation fm. Results for cdma without secure scrambling under disguised jamming, the kernel of the avc corresponding to a cdma system without secure scrambling, w 0, is symmetric. Generate a local pseudorandom code with a higher rate than the data to. Andrews wireless networking and communications group wncg. Code division multiple access for wireless communications. Apr 08, 2020 chapter cdma code division multiple access, ppt, semester, engineering computer science engineering cse notes. To pick out the signal of specific user, this signal is modulated with a unique code sequence. Blind chip rate estimation in multirate cdma transmissions using multirate sampling at slow flat fading channels, iccs08, 19 to 21 nov 2008 in guangzhou, china. Consultancy for gis based slum mapping, preparation of slum redevelopment models and slumfree city plan, and dprs for slums in tirupati municipal corporation under ray. This is done in gsm via gaussian minimum shift keying gmsk. Cdma appears to be an underdog for 4g, but still may win. If so, share your ppt presentation slides online with.
Gsm standard still evolving and improved with new features and services. To continue with cdma we next discuss spread spectrum techniques. The core principle of spread spectrum is the use of noiselike carrier waves, and, as the name implies, bandwidths much wider than that required for simple pointtopoint communication at the same data rate. The receiver, knowing the code sequence of the user, decodes the received signal and recovers the original data. When someone is editing your presentation, you can see their cursor as they make changes or highlight text.
Discussion of receivers for ofdm and mccdma intercarrier interference, fft. Chapter 7 multiplexing techniques temple university. Cdma cellular systems are deemed superior to fdma and tdma, which is why cdma plays a critical role in building efficient, robust, and secure radio communication systems. References to these chapters and their contents are given on this page. Robust cdma receiver design under disguised jamming. Cdma issues so far, cdma looks like a step backwards.
Used in gsm cdma code division multiple access all users share the same frequency all the time. Heaton or tfi regarding reproducing presentation material. Code division multiple access each user is assigned a binary, direct sequence code during a call. All pro users are now able to generate a pdf version of their decks at the click of a button. Individual conversations are encoded with a pseudorandom digital sequence. Multiple users want to communicate in a common geographic area cellular example. Lets take a simple analogy to understand the concept of cdma.
Ppt technical introduction to cdma powerpoint presentation. In the action settings box, select the mouse click tab if you want to open the pdf with a click, or the mouse over tab if you want it to open when you move the pointer over the pdf file icon. Cdma development in cameroon 1 itubdt regional seminar on broadband wireless access bwa for rural and remote areas for africa cdma development in cameroon mr. Impact of interference model on capacity in cdma cellular networks showing 14 of 22 slides in this presentation. Cdma is the base on which access methods such as cdmaone, cdma2000, and wcdma are built. Collaborate for free with an online version of microsoft powerpoint. If you dont want to save slides, but instead only save comments, handouts, or outline view, under publish what, select an appropriate option. Download 3g ppt presentation slides and seminar report in pdf for free for cse students. The slides editor is available right in your browser. Multicarrier cdma communications system design dongming chuang andyucong gu ee382c spring 1998. Multicarrier cdma in which symbols are spread over large vectors most of whose elements are zero sparse.
The usrp will relay the appropriate cdma control channel, and then the fpga will process the data to discover current calls on the network. Under disguised jamming, the deterministic capacity of a cdma system without secure scrambling is zero c bawc paper presentation for ieee icassp 2016 march, 2016 22. Save powerpoint presentations as pdf files office support. Chapter 6 wireless and mobile networks a note on the use of these ppt slides. Prasad, an overvies of cdma evolution toward wideband cdma, ieee, 1998. It has gained widespread international acceptance by cellular radio system operators as an upgrade that will dramatically increase both their system capacity and the service quality.
Code division multiple access cdma also known as is95 is a spread spectrum technology platform that enables multiple users to occupy the same radio channel or frequency spectrum at the same time. Ssma s pread s pectrum m ultiple a ccess carrier is 1 st modulated by info wave its again modulated by unique code waveform the 2 nd modulation is done to spread the spectrum over available bw therefore cdma is also called ssma let the info. In powerpoint, select the slide that you want to add the file to, and then select insert object. Select the pdf file you want to convert to powerpoint. This makes the pdf file part of the presentation file.
Tight synchronization is required to use orthogonal codes, which then break in a multipath channel anyway quasiorthogonal codes cause selfinterference, which dominates the performance in most cdma systems nearfar problem is a serious hindrance, requiring fast and. Code division multiple access seminar report, ppt, pdf. Doherty, performance characteristics of the is95 standard for cdma spread spectrum mobile communication systems, ieee, 1997. The multicarrier cdma system is a novel 3rd generation mobile communication system. To save specific slides as pdf, in slides s, enter the slide number range in from and to boxes. All users use same frequency and may transmit simultaneously narrowband message signal multiplied by wideband spreading signal, or codeword each user has its own pseudocodeword orthogonal to others. Click share and let anyonefriends, classmates, coworkers, familyview, comment on or edit your presentation. Impact of interference model on capacity in cdma cellular. Get more information about ppt presentation cell phone jammer by visiting this link. We propose to build a system that will use software radio to inspect reverse control channel traffic of a cellular cdma system. Sprints network vision initiative move to a single multistandard converged mobile network reduce the number of cell site s in the system by 22,000 enhance 3g cdma as well as 4g lte coverage to reduce roaming charges. Scribd is the worlds largest social reading and publishing site.
Nov 30, 2012 cdma technology ppt paper presentation video gives over view on how it woks advantages an disadvantages of cdma technology. Explore code division multiple access with free download of seminar report and ppt in pdf and doc format. Our free powerpoint backgrounds and presentation templates are very easy to customize and edit for your presentation needs. Qualcomm incorporated includes qualcomm s licensing business, qtl, and the vast majority of its patent portfolio. Gsm and cdma spectrum frequencies the cdma network operates in the frequency spectrum of cdma 850 mhz and 1900 mhz while the gsm network operates in the frequency spectrum of gsm 850 mhz and 1900 mhz.
Generate a local pseudorandom code with a higher rate than the data to be transmitted. Slides from mobilemonday indonesia events 20082009. By utilizing our pdf to powerpoint converter, you can convert a pdf to ppt free in just seconds. May 05, 2010 code division multiple access introduction cont.
The bandwidth of the coded data signal is chosen to be much larger. Technical introduction to cdma course outline basic cdma principles coding forward and reverse channels cdma operational details multiplexing, forward and reverse. Cdma is a form of spreadspectrum, a family of digital communication techniques that have been used in military applications for many years. Robust again narrowband interference ldisadvantages. Chapter cdma code division multiple access, ppt, semester. Multicarrier transmission over mobile radio channels jeanpaul m. Multicarrier transmission over mobile radio channels.
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