Results 161 to 170 of about 70,898 (211)
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5th IEEE International Symposium on Personal, Indoor and Mobile Radio Communications, Wireless Networks - Catching the Mobile Future., 2002
The multiple access schemes TDMA and CDMA are compared and evaluated with respect to the demands on third generation mobile radio systems such as high capacity and flexibility. Further, an approach to evolve GSM towards third generation mobile radio systems by introducing an optional CDMA component is presented.
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The multiple access schemes TDMA and CDMA are compared and evaluated with respect to the demands on third generation mobile radio systems such as high capacity and flexibility. Further, an approach to evolve GSM towards third generation mobile radio systems by introducing an optional CDMA component is presented.
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5th IEEE International Symposium on Personal, Indoor and Mobile Radio Communications, Wireless Networks - Catching the Mobile Future., 2002
Using a soft limiter of the error function type, the authors have applied the time domain Fourier expansion method to analyze intermodulation in multiplexing of CDMA signals. The individual three-tone third-order intermodulation component, normalized with respect to the signal in CDMA, has the same magnitude as that in FDMA except for the reduction by ...
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Using a soft limiter of the error function type, the authors have applied the time domain Fourier expansion method to analyze intermodulation in multiplexing of CDMA signals. The individual three-tone third-order intermodulation component, normalized with respect to the signal in CDMA, has the same magnitude as that in FDMA except for the reduction by ...
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IEEE Global Telecommunications Conference, 2004. GLOBECOM '04., 2005
Our topic is channel equalizer quantization for a cellular handset. We answer questions regarding quantization of variables internal to the equalizer using some estimated bounds and simulation. This includes the catastrophic event of breakdown due to a roundoff-induced singularity in Cholesky factorization.
Thomas A. Sexton +5 more
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Our topic is channel equalizer quantization for a cellular handset. We answer questions regarding quantization of variables internal to the equalizer using some estimated bounds and simulation. This includes the catastrophic event of breakdown due to a roundoff-induced singularity in Cholesky factorization.
Thomas A. Sexton +5 more
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Gated-CDMA: Frequency-Domain Equalization for CDMA Systems
IEICE Transactions on Communications, 2005While CDMA systems are proven to be excellent solutions for cellular communications, they suffer from severe multi-path interferences and are hard to support high-data-rate transmissions over frequency-selective fading channels. This letter introduces a novel downlink transmission method for next generation mobile communication systems.
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Performance Analysis of DS-CDMA and MC-CDMA Systems
2018 9th IEEE Annual Ubiquitous Computing, Electronics & Mobile Communication Conference (UEMCON), 2018In this paper, a performance analysis of DS-CDMA and MC-CDMA is conducted. With DS-CDMA, data is spread using a spreading sequence in the time domain. In contrast, with MC-CDMA, data is spread over different sub-carriers using a spreading sequence in the frequency domain. The comparison of DS-CDMA and MC-CDMA is presented under an AWGN channel.
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On Asymptotic Efficiency for Asynchronous CDMA
2007 41st Annual Conference on Information Sciences and Systems, 2007We consider asynchronous CDMA systems and analyze their performances in terms of asymptotic efficiency when linear receivers are employed and the system becomes overloaded. We show that in such systems, differently from synchronous systems, linear detectors can be asymptotically efficient and, specifically, that the MMSE detector is asymptotically ...
ROMANO, Gianmarco +3 more
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Performance of VSG-CDMA and MC-CDMA in multirate systems
IEEE VTS 53rd Vehicular Technology Conference, Spring 2001. Proceedings (Cat. No.01CH37202), 2002The performance of two multirate schemes in DS/CDMA systems, variable spreading gain (VSG-CDMA) and multicode (MC-CDMA) are compared. We first present the signal model for a multirate DS/CDMA system. Then, the performance in terms of asymptotic multiuser efficiency (AME), near-far resistance (NFR), and BER are evaluated.
null Zihua Guo, K.B. Letaief
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Frequency coordination between CDMA and non-CDMA systems
Proceedings of 1995 IEEE MTT-S International Topical Symposium on Technologies for Wireless Applications (Conjunction with INTER COMM'95), 2002Mutual interference between non-CDMA (FM and TDMA) subscriber stations (SS) and CDMA base stations (BS), as well as interference between CDMA SS and non-CDMA BS are investigated. The noise figure is used as a measure of degradation of the receiver performance.
S. Soliman, C. Wheatley
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Comparison of CS-CDMA and MC-CDMA : BER and PAPR
MILCOM 2008 - 2008 IEEE Military Communications Conference, 2008In this paper, a cyclic prefix code division multiple access (CP-CDMA) system with the use of comb spectrum (CS) code, so called CS-CDMA, is described and a comparison between the CS-CDMA and the Multi-carrier code division multiple access (MC-CDMA) is implemented in terms of the bit error rate (BER) performance and peak to average power ratio (PAPR ...
null Hongbing Cheng +2 more
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CDMA with Partitioned Spreading
IEEE Communications Letters, 2007An enhancement to code-division multiple access (CDMA) is proposed whereby the signature sequences are partitioned into sections, which are interleaved before transmission. A multistage receiver successively forms soft-bit estimates based on the received sections, which are used to reduce the interference in subsequent stages via signal cancellation ...
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