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| | Wavelength Division Multiplexing |
 | | The multiplexing and demultiplexing of the SCM channels is accomplished electronically, not optically. | | | The cross-connect is composed of wavelength demultiplexers for the input stage, wavelength multiplexers for the output stage, and fibers interconnecting the two stages. | | | Yet another optical multiplexing scheme is called space-division multiplexing (SDM), in which the channel-routing path is determined by different spatial position (i.e., a different output fiber). |
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http://www2.rad.com/networks/1999/wdm/wdm.htm
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| | Code division multiple access - Wikipedia, the free encyclopedia |
| | CDMA also refers to digital cellular telephony systems that makes use of this multiple access scheme, such as those pioneered by Qualcomm, or W-CDMA. | | | Then this will also disrupt the orthogonality property, and thus adding an extra level of forward error correction (FEC) coding is also vital. | | | Suppose that noise present in a channel takes a zero bit to some other value. |
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http://en.wikipedia.org/wiki/CDMA
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| | Theory of Code Division Multiplexing - Tutorial - Development Library - National Instruments |
| | The spreading code is being clocked at a rate three times as fast as the source is outputting information. | | | Spreading can be used as a multiplexing technique by developing a series of orthogonal spreading codes. | | | The receiver has advance knowledge of the spreading code and uses this knowledge to recover the information from the received, spread-out signal. |
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http://zone.ni.com/devzone/conceptd.nsf/webmain/58B2834DE12D473C86256E00007AAFB5
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| | High reflectivity superstructured FBG for coherent optical code generation and recognition |
| | The auto-correlation peak (PA) and the ratios of PA to the maximum wing level (P/W) and cross-correlation level (P/C) were used to quantitatively evaluate the OC recognition performance. | | | High reflectivity superstructured FBG for coherent optical code generation and recognition | | | X. Wang, K. Matsushima, A. Nishiki, N. Wada, and K. Kitayama, "High reflectivity superstructured FBG for coherent optical code generation and recognition," Opt. |
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http://www.opticsexpress.org/abstract.cfm?URI=OPEX-12-22-5457
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| | Code-Division Multiplexing of a Sensor Channel: A Software Implementation |
| | It describes code-division multiplexing (CDMA) and time-division multiplexing (TDMA) of a receiver channel in an electric field sensing system. | | | This paper demonstrates the use of software radio techniques in the context of sensing, rather than communications. | | | Code-Division Multiplexing of a Sensor Channel: A Software Implementation |
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http://www.comsoc.org/sac/private/1999/apr/725_17sac04-smith.html
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| | Optimal Resource Management in Packet-Switching TDD CDMA Systems |
| | The mapping is a function of the modulation and channel coding scheme used, diversity, Rake receiver structure, and so on [7]. | | | Slots are defined in both time and code domains. | | | An optimal packet scheduling algorithm is proposed to allocate system resources to each user for QoS provisioning and high resource utilization. |
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http://www.comsoc.org/pci/private/2000/dec/zhuang.html
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| | DOR Home Page |
| | Although CDM and CDMA in general have been used extensively in prior art for communication, they are employed to transmit information from transmitters to receivers, but not for optical sensing of the transport medium or object. | | | Common optical sensing apparatus that this invention can be applied to, but not exclusively for rare laser radars (also known as ladars or lidars), and optical diffuse tomography systems. | | | 2003-041 Orthogonal Code-Division Multiplexing of Multi-Transmitter Optical Sensing System |
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http://www.research.uh.edu/otm/photoopticaldesc.htm
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| | MULTICARRIER MODULATION CODE DIVISION MULTIPLE ACCESS |
| | Therefore, any multipath or delayed version of the spread signal will be mitigated at receiver. | | | CDMA has numerous inherent advantages that are derived from the spectral spreading. | | | A brief overview of the two component technologies underlying MC-CDMA and OFDM is will be presented in this section. |
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http://www.stanford.edu/~lawoniyi/mcm7.htm
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| | 65 |
| | The propagation of the codes over a 476 km optical link of the National Transparent Optical Network was measured in conjunction with the Lawrence Livermore National Laboratory, and means of modulating the laser sources for coding were measured in conjunction with the Caltech/Jet Propulsion Laboratory. | | | The concept could be readily extended to metropolitan topologies as well as to distributed computing networks in a building or a floor, or to the distribution of HDTV on demand. | | | This project will combine code division multiplexing with wavelength division multiplexing to produce a large number of communication channels that support bursty, asynchronous, concurrent communications. |
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http://www.er.doe.gov/sbir/awards_abstracts/sbirsttr/cycle19/phase2/065.htm
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| | Terabit Optical Code Division Multiplexed Local Area Networks |
| | Among multiplexing schemes which have been considered are: Time Division Multiplexing, (TDMA), Wavelength (WDM), and Code Division Multiplexing, (CDMA). | | | Terabit Optical Code Division Multiplexed Local Area Networks | | | Instead to access the full 10Tbps processing capability, the signals must be multiplexed onto a single common medium with the capability for rapid switching among channels. |
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http://www.ucop.edu/research/micro/abstracts/98_178.html
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| | Fiber optics and optical communications : Fiber optics links and subsystems |
| | Bandwidth Optimization of Optical Data Links by Use of Error-Control Codes | | | Design of Efficient All-Optical Code-Division Multiplexing Systems Supporting Multiple-Bit-Rate and Equal-Bit-Rate Transmissions | | | Wavelength Control of Tunable Dense Wavelength-Division Multiplexing Sources by Use of a Fabry-Perot Etalon and a Semiconductor Optoelectronic Diode |
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http://ao.osa.org/ocisdirectory/060_2360.cfm
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| | Wavelength division multiplexing - FreeEncyclopedia |
| | In telecommunications wavelength division multiplexing (WDM) is multiplexing several optical carrier[?] n signals on a single optical fibre by using different wavelengths (colours) of laser light to carry different signals. | | | See also time division multiplexing, code division multiplexing. | | | Note that this term applies to an optical carrier (which is typically described by its wavelength), whereas frequency division multiplexing typically applies to a radio carrier (which is more often described by frequency). |
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http://openproxy.ath.cx/wa/Wavelength_Division_Multiplexing.html
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| | Title page for ETD etd-05022000-15590055 |
| | using code division multiplexing was feasible and that the mixed signal demultiplexing software unique to | | | multiplexing by taking a novel approach to network different-type sensors using software and signal | | | performed with the results showing that the ultimate number of sensors that could be multiplexed with |
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http://scholar.lib.vt.edu/theses/available/etd-05022000-15590055
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| | NASA Tech Briefs: Adaptive multiplexing for free-space optical communication |
| | NASA Tech Briefs: Adaptive multiplexing for free-space optical communication | | | In the transmitter, a code sequence comprising five parallel bits during each bit period would control the simultaneous generation (for "1") or nongeneration (for "0") of pulses by five laser diodes, each operating at a different one of five wavelengths ((lambda)^sub 1^ through (lambda)^sub 5^). | | | The figure illustrates an example of a simple system that would utilize a combination of wavelength-division multiplexing and time-spread code-division multiplexing to increase security. |
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http://www.findarticles.com/p/articles/mi_qa3957/is_200204/ai_n9070976
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| | Japan group claims optical transport breakthrough |
| | Japan's National Institute of Information and Communications Technology and Oki Electric Industry claimed a first on Wednesday with the carriage of data using a next-generation optical transmission technology on a metropolitan-area fiber-optic network. | | | Technologies such as dense wavelength division multiplexing already exist to squeeze more bandwidth out of an optical fiber, but researchers involved in the demonstration said OCDM can accomplish the task more economically and flexibly. | | | OCDM is a method for sending more than one signal down an optical fiber. |
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http://www.networkworld.com/edge/news/2004/0730japangroup.html
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| | CDMA (Code Division Multiple Access) |
| | CDMA is a form of wireless multiplexing, in which data can be sent over multiple frequencies simultaneously, optimizing the use of available bandwidth. | | | In a CDMA system, data is broken into packets, each of which are given a unique identifier, so that they can be sent out over multiple frequencies and then re-built in the correct order by the receiver. |
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http://www.networkworld.com/details/464.html
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| | Phone Network Info |
| | This process is very similar to time division multiplexing performed on T1 and E1 digital telephone circuits. | | | The reverse process is performed on the opposite end of the call. |
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http://www.bashour.com/wired/phone_network_info.htm
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