Results 151 to 160 of about 70,898 (211)
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Spectral overlay of multicarrier CDMA on existing CDMA mobile systems
IEEE Communications Letters, 1999A spectral overlay of a narrow-band code division multiple access (CDMA) system and a wide-band multicarrier CDMA system is considered as a means for existing CDMA mobile networks to evolve into a future CDMA network. The achievable joint capacity of the overlaid system is provided and compared with that of another network evolution strategy of ...
Dongwoo Kim
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Spreading codes for direct sequence CDMA and wideband CDMA cellular networks
IEEE Communications Magazine, 1998This article presents an overview of the spreading techniques for use in direct sequence CDMA cellular networks. We review the theoretical background for sequences used in CDMA and wideband CDMA, and discuss the main characteristics of the maximal length, Gold (1967, 1968), and Kasami sequences, as well as variable- and fixed-length orthogonal codes ...
Esmael Dinan, Bijan Jabbari
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A Capacity Comparison Between MC-CDMA and CP-CDMA
IEEE Vehicular Technology Conference, 2006In this paper, we consider the capacity behaviors of MC-CDMA and CP-CDMA systems by the uses of MMSE receivers. The averaged capacities are derived for the two systems, having a finite spreading factor, in Rayleigh fading environment. The closed-form solutions have been obtained, which show that the capacity of the MC-CDMA is slightly larger than that ...
Meng Ma +3 more
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DS-CDMA, MC-CDMA and MT-CDMA for mobile multi-media communications
Proceedings of Vehicular Technology Conference - VTC, 2002We present a comparison between direct sequence code division multiple access (DS-CDMA), multi-carrier (MC-) CDMA and multitone (MT-) CDMA schemes in terms of the transmitter and receiver structure. We discuss their down-link bit error rate performance in a frequency selective Rayleigh fading channel by computer simulation.
S. Hara, R. Prasad
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International Journal of Wireless Information Networks, 1995
A Broadband Code Division Multiple Access (B-CDMA) technique is presented that will overlay the existing cellular telephone spectrum (825 to 894MHz). The overlay will provide additional capacity to the network while allowing high quality voice and high speed data services to be coexistent with the existing cellular services (AMPS and TDMA).
Donald L. Schilling +3 more
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A Broadband Code Division Multiple Access (B-CDMA) technique is presented that will overlay the existing cellular telephone spectrum (825 to 894MHz). The overlay will provide additional capacity to the network while allowing high quality voice and high speed data services to be coexistent with the existing cellular services (AMPS and TDMA).
Donald L. Schilling +3 more
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A survey on CDMA: evolution towards wideband CDMA
1988 IEEE 5th International Symposium on Spread Spectrum Techniques and Applications - Proceedings. Spread Technology to Africa (Cat. No.98TH8333), 2002This paper presents an overview of CDMA and discusses the main features of the future air interface access schemes namely WCDMA and CDMA2000, for IMT-2000/UMTS. Multiple access schemes and CDMA classification are introduced. CDMA past, present and future activities are presented, and the concepts and elements of CDMA are explained.
R. Prasad, T. Ojanpera
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Proceedings of IEEE Vehicular Technology Conference (VTC), 2002
CDMA mobile stations using the North American cellular system rely upon the IS-41 network protocol for intersystem handoff and roaming. This paper describes the IS-95 air interface and corresponding IS-41 protocols for intersystem handoff, mobile station location determination, and call delivery.
Alejandro R. Holcman +1 more
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CDMA mobile stations using the North American cellular system rely upon the IS-41 network protocol for intersystem handoff and roaming. This paper describes the IS-95 air interface and corresponding IS-41 protocols for intersystem handoff, mobile station location determination, and call delivery.
Alejandro R. Holcman +1 more
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An overview of CDMA evolution toward wideband CDMA
IEEE Communications Surveys & Tutorials, 1998Third-generation mobile radio networks, often dubbed as 3G, have been under intense research and discussion recently and will emerge around the year 2000. In the International Telecommunications Union (ITU), third generation networks are called International Mobile Telecommunications-2000 (IMT-2000), and in Europe, Universal Mobile Telecommunications ...
Ramjee Prasad, Tero Ojanpera
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Proceedings of the Sixth IEEE Computer Society Workshop on Future Trends of Distributed Computing Systems, 2002
This paper shows how reliable data services can be provided in an error prone wireless environment using CDMA and a link layer retransmission protocol. A CDMA encoder using Walsh codes for 1.85 to 1.99 GHz PCS applications is simulated under various error conditions with varying packet size to determine minimum acceptable QOS relative to error ...
David Cypher, Shukri Wakid
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This paper shows how reliable data services can be provided in an error prone wireless environment using CDMA and a link layer retransmission protocol. A CDMA encoder using Walsh codes for 1.85 to 1.99 GHz PCS applications is simulated under various error conditions with varying packet size to determine minimum acceptable QOS relative to error ...
David Cypher, Shukri Wakid
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IEEE Journal on Selected Areas in Communications, 1995
A method for optical signaling is investigated that allows multiple transmitters to simultaneously use the same noncoherent receiving aperture. The signaling is based on the properties of laser speckle interference patterns. Capacity for an interference limited system is explored for a correlation receiver based on random coding.
Hassan, Amer A. +2 more
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A method for optical signaling is investigated that allows multiple transmitters to simultaneously use the same noncoherent receiving aperture. The signaling is based on the properties of laser speckle interference patterns. Capacity for an interference limited system is explored for a correlation receiver based on random coding.
Hassan, Amer A. +2 more
openaire +2 more sources