Confusion between db and dbm is one of the most common mistakes when working with optical networks. In this paper we investigate the application of cdma in optical communication networks. Code division multiple access all users share the same radio frequency at the same time. This tutorial is helpful for a beginner who wants to acquire knowledge on the communication systems. Principles of communication i about the tutorial in this tutorial, the basic concepts of communications along with the important concepts of analog and digital communications have been covered. Wireless communication multiple access tutorialspoint. The proposed system is compared with most of the receiver structures in the. When the ray trace is complete, click the green checkmark. A full ray trace calculates the ray trace using both the optical and mechanical components in the computational domain. Advances in spectral optical codedivision multipleaccess. Technique, parameters and applications rajesh yadav1, dr. Elbadawy, performance limitations in the r3t optical random access cdma protocol, submitted for possible publication to osa j. Basic manipulation of electrical signals tutorial 4.
In this tutorial paper after giving a brief listing of relevant concepts in optical communications concepts of optical spectrum spreading, techniques of temporal and spectral coding are. In this tutorial paperafter giving a brief listing of relevant concepts in optical. Tutorial on basic link budget analysis abstract advances in the stateoftheart have made wireless technology a more compelling solution for many consumer applications. Pdf probability density function pin photodiode with a lightly doped, intrinsic, semiconductor region between the ptype and ntype regions pon passive optical network ppm pulse position modulation rs reedsolomon codes sdh synchronous digital hierarchy snr signal to noise ratio soa semiconductor optical amplifiers. Code division multiple access technique is an example of multiple access where several transmitters use a single channel to send information simultaneously. This allows several users to share a band of frequencies see bandwidth.
Seminar on optical code division multiple access submitted by murtadha ali nsaif shukur m. The technicality of cdma generation has given huge benefits over other parallel technology in terms of spectrum performance and overall performance. This paper won the 1st position in paper evaluation and 3rd position after presentation, ieee egyptian student. Audience this tutorial has been designed for readers who want to understand the basics of gsm in very. Gurjitkaur2 1 school of information and communication technology, g. Most of researches in optical cdma networks were concentrated in the physical layer. Although associated mostly with wireless cellular communication, cdma is also being considered for optical channels. Working with optical parameterized signals and noise bins. Formats and pricing details are shown on the book product pages. Code division multiple access for wireless communications. All optical subscriber access networks will be quite limited most of the access network is expected to be dominated by wireless. Basics of code division multiple access cdma spie digital library. Pdf analysis of mac protocols with correlation receiver. Optical code division multiple access o cdma is evolving into a promising candidate for access networks, due to its potential for enhanced information security.
Research in this field started two decades ago or so and is still flourishing. Prevention properties of optical cdma and y00 quantum stream cipher against signal alternation attacks conference paper pdf available. Single integrated device for optical cdma code processing. Codedivision multiple access cdma is a channel access method used by various radio communication technologies. Interference mitigation using successive interference. Cdma application in optical communication seamed to be reasonable as well. A transmitting user in the system encodes the optical signal using a first coding mask, and a receiving user decodes the received signal using two decoding masks, all of the masks having lengths n. Since the mid 1990s, the role of optical cdma has expanded from local area networks to longer span, telecommunicationtype networks. Optical fibers contd data communication in an optical network use an optical carrier signal at some wavelength in the bandof 1450 to 1650 nm, at the source of the data, modulate the carrier with the data to be communicated, sendthe modulatedcarrier towards the destination using a path involving one or more fibers. If the user is transmitting the data bit one, its transmitter sends codeword otherwise no signal is sent. Everything you always wanted to know about optical. Wavelength is used in optical fiber communication systems to partition channels.
Multiple optical private networks over epon using optical cdma technique. To permit this without undue interference between the users, cdma. Analysis of indoor wireless infrared optical cdma lan. About the tutorial gsm tutorial gsm is a globally accepted standard for digital cellular communications. Cellular underwater wireless optical cdma network arxiv. That is, a decibel relative to 1 milliwatt mw of power. Kahn, designing highperformance multimode fibers using refractive index shape optimization, subm. Introduction to wireless communications and networks. Digital messages are constructed with a finite number of symbols.
Optical code division multiple access o cdma is evolving into a promising candidate for access networks, due to its potential for enhanced. Pdf multiple optical private networks over epon using. Department of electronics engineering, igit, sarang, india. Pdf optical cdma detection by orthogonal matching pursuit. Hamarshehc aphotonics technology laboratory ptl, institute of micro engineering and nanoelectronics, universiti kebangsaan malaysia, 43600 ukm bangi, selangor, malaysia. Electrical pulse shaper with mary input tutorial 5. The optimal singleuser detector article pdf available in ieee communications letters 54. Single integrated device for optical cdma code processing in dualcode environment yuekai huang1, ivan glesk 1, christoph m. Nr dimensional integral in 21 can effectively be calculated through an nt. Fibers, bragg gratings, optical amplifiers and optical switches k. There are, however, a few authors that have examined the network or link layer of optical. Your contribution will go a long way in helping us. Introduction to cdma code division multiple access cdma is a radically new concept in wireless communications. It has gained widespread international acceptance by cellular radio system operators as an upgrade that will dramatically increase both their system capacity and the.
Prucnal 1 1department of electrical engineering, princeton university, princeton, nj 08544 usa 2lightsmyth technologies inc. This poses a problem to many practicing engineers and technology managers who are unfamiliar with the relevant concepts and terminology. To continue with cdma we next discuss spread spectrum techniques. 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. Optical codedivision multiple access using broadband. Interference mitigation using successive interference cancellation in optical cdma systems tawfig eltaifa, hossam m. Pdf effect of shiftzcc codes for optical cdma system. Especially, optical code division multiple access cdma systems have been shown to be competitive candidates to support a large number of simultaneous users 112. Analog communications 1 analog and digital signals messages are digital or analog. Osa strategies for realizing optical cdma for dense. They also have a single autocorrelation peak at zero, just like ordinary pn sequences. Cdma is much recommended for voice and data communications. This paper investigates optical power control to enhance capacity of optical cdma star coupled networks. Code division multiple access cdma oe and eo interfaces cannot operate above few tens of gbit s.
Pdf code for spectral amplitude coding optical cdma. Code division multiple access cdma is a digital air interface standard, claiming eight to fifteen times the capacity of analog. Gsm uses narrowband time division multiple access tdma for providing voice and text based services over mobile phone networks. Optical fiber based communication systems has advantage of having access to large bandwidth and ultrahigh speed signal processing are possible. Each users optical cdma decoder is matched to its intended signal. Optical cdma system using prime sequence codes are analyzed. In order to play a significant role in these longer span, denser, higher data rate networks, optical cdma code set must 1 have at least as many codes as dense wavelength division multiplexing wdm i. Cdma tutorial for beginners learn cdma online training. To achieve multimedia transmission in ocdma, we have. Multiclass optical orthogonal codes, optical power control, and polarization encoding manuscript submitted 18. Optical code division multiple access linkedin slideshare. Cdma appears to be an underdog for 4g, but still may win ongoing research on cdma. Optical codedivision multiple access o cdma combines the large bandwidth of the fiber medium with the flexibility of the cdma technique to achieve highspeed connectivity. Cdma i about the tutorial code division multiple access cdma is a channel access method normally used by 3g radio communication technology as well as in some other technologies.
Tutorial on basic link budget analysis spread spectrum. Cdma is an example of multiple access, where several transmitters can send information simultaneously over a single communication channel. We consider a network in which the nodes encode their optical. Pdf as spectrum spreading and cdma proved themselves as very efficient in. An optical fiber communications system using spread spectrum code division multiple access techniques to achieve better bandwidth utilization. Us6236483b1 optical cdma system using subband coding. Cellular underwater wireless optical cdma network ieee xplore. In cdma every user uses the full available spectrum instead of getting allotted by separate frequency. Analysis of mac protocols with correlation receiver for optical cdma networks part i. Gold sequences are in useful in nonorthogonal cdma. The technicality of cdma technology has given significant advantages over other parallel technologies in terms of spectrum efficiency and overall performance. Tutorial texts are standalone tutorials covering fundamental topics in optical science and technology at introductory and intermediate levels.
Cdma was originally investigated in the context of radio frequency communications systems, and was first applied to the optical domain in the mid1980s 1, 2. A baseline ray trace considers only optical components in the computational domain. The block diagram of proposed optical cdma decoder. Cdma 2000 is mostly an orthogonal cdma system gold sequences have only three crosscorrelation peaks, which tend to get less important as the length of the code increases. In this paper, we present a novel optical cdma multiuser detector employing the orthogonal matching pursuit algorithm.
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