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New direction of broadband wireless technology

Fumiyuki Adachi, Eisuke Kudoh
2007 Wireless Communications and Mobile Computing  
CDMA is very flexible; special cases of DS-CDMA and MC-CDMA with the spreading factor SF = 1 are non-spread SC transmission and OFDM, respectively.  ...  Either SC or MC can be used for the downlink (base-to-mobile) to achieve almost the same bit error rate (BER) performance.  ...  Coherent rake combining, used in 3G DS-CDMA systems, is a timedomain equalizer and its performance tends to be severely limited by the large inter-path interference (IPI) as the channel selectivity gets  ... 
doi:10.1002/wcm.507 fatcat:6frt3jwrmbbpbj4cfoyptd4e5y

Reverse Link Performance of DS-CDMA Cellular Systems through Closed-Loop Power Control and Beamforming in 2D Urban Environment

Mohamad Dosaranian-Moghadam, Hamidreza Bakhshi, Gholamreza Dadashzadeh
2010 International Journal of Computer Networks & Communications  
Also, we study an analytical approach for the evaluation of the impact of power control error (PCE) on DS-CDMA systems in a 2D urban environment.  ...  In this paper, we propose smart step closed-loop power control (SSPC) algorithm in direct sequence-code division multiple access (DS-CDMA) receivers in a 2D urban environment.  ...  RAKE RECEIVER PERFORMANCE ANALYSIS The RAKE receiver structure in the DS-CDMA system is shown in Figure 1 .  ... 
doi:10.5121/ijcnc.2010.2610 fatcat:zkxsjkhplzcqfnq4cqbcsdviim

Performance of CDMA system using Antenna Arrays with Power Control Error in a Rayleigh Fading

A. Fouda, H. Elesawy, W. Swlam
2014 The International Conference on Electrical Engineering  
The multiple access interference (MAI) problems can be overcome by power control by the process so that the average received power at base station is same for each user.  ...  Antenna arrays have been recognized by most fourth generation CDMA systems proposals as a way to enhance the capacity and system coverage by effectively combating multipath fading and mitigating co-channel  ...  error probability of 1-D and 2D-RAKE receiver as the probability of error of the CDMA system for Rayleigh fading channel and antennas.  ... 
doi:10.21608/iceeng.2014.30384 fatcat:au43qnic55bjlblsgkkvef6fja

Joint Frequency-Domain Differential Detection and Equalization for 2-Dimensional Spread/Chip-Interleaved DS-CDMA Uplink Transmissions

Le Liu, Fumiyuki Adachi
2006 IEEE Vehicular Technology Conference  
The multiple-access interference (MAI) limits the performance of the DS-CDMA uplink transmission. 2 dimensional (2D) spread/chip-interleaved DS-CDMA is an MAI-free system, where single-user coherent frequencydomain  ...  Computer simulation results show that 2D spread/chipinterleaved DS-CDMA using FDDDE is robust against fast fading.  ...  INTRODUCTION Direct sequence-code division multiple access (DS-CDMA) has been adopted as one of multiple access schemes in the 3 rd generation (3G) wireless communication systems [1] .  ... 
doi:10.1109/vtcf.2006.369 dblp:conf/vtc/LiuA06 fatcat:hs3qodeepzc45ib773ehnkqb3q

2D Markovian SS codes flatten time-frequency distribution of signals in asynchronous Gabor division CDMA systems

Tohru Kohda, Yutaka Jitsumatsu, Kazuyuki Aihara
2011 2011 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP)  
We propose a Gabor division (GD)-CDMA system which permits time and frequency offsets.  ...  In this paper, we show that such negatively correlated spreading codes have another important property that they flatten the time-frequency energy distributions of signals in GD-CDMA system.  ...  In this paper, DS-CDMA is referred to as a time division CDMA (TD-CDMA). The FD-CDMA system, on the other hand, was defined as a frequency dual of chip-asynchronous DS/CDMA [4] .  ... 
doi:10.1109/icassp.2011.5946687 dblp:conf/icassp/KohdaJA11 fatcat:juulx4r2vjc5vcz7vjve5zqoy4

System aspects of smart-antenna technology in cellular wireless communications-an overview

A.O. Boukalov, S.-G. Haggman
2000 IEEE transactions on microwave theory and techniques  
We surveyed the three main system aspects of smart antenna (SA) technology in wireless communications i.e. SA receiver, wireless network control and planning with SA.  ...  We discuss system integration of SA receivers taking into consideration expected propagation conditions, user mobility and offered traffic.  ...  The author wishes to thank the Helsinki University Language Centre for language revision of the manuscript and anonymous reviewers for their fruitful comments.  ... 
doi:10.1109/22.846718 fatcat:cyxlgac275h3pfv6b6lx22evlq

Improved Performance Analysis for Maximal Ratio Combining in Asynchronous CDMA Channels

Wan Choi, Jeffrey Andrews
2007 IEEE Transactions on Wireless Communications  
The contribution of this paper is to provide a general framework for accurately analyzing the performance of the diversity receiver in CDMA systems without these compromising approximations.  ...  Direct Sequence Code Division Multiple Access (DS-CDMA) receivers typically use Maximal Ratio Combining (MRC) to favorably combine the energies of distinct multipath components from diversity branches.  ...  On the bit error probability analysis for MRC reception in DS-CDMA, there has been a large number of studies including a vast literatures on 2D-RAKE receivers.  ... 
doi:10.1109/twc.2007.06049 fatcat:laiwx44rtjarhmnevipd5qdh5y

A CDMA-based Medium Access Control for UnderWater Acoustic Sensor Networks

Dario Pompili, Tommaso Melodia, Ian F. Akyildiz
2009 IEEE Transactions on Wireless Communications  
CDMA is the most promising physical layer and multiple access technique for UW-ASNs because it is robust to frequencyselective fading, it compensates for the effect of multipath at the receiver, and it  ...  UW-MAC is the first protocol that leverages CDMA properties to achieve multiple access to the scarce underwater bandwidth, while other protocols tailored for this environment have considered CDMA merely  ...  In DS-CDMA communication systems, the information-bearing signal is directly multiplied by a spreading code with a larger bandwidth than the data.  ... 
doi:10.1109/twc.2009.080195 fatcat:6orwlrpq5zfcjgb25vz2pnw3xm

Full Physical Layer Simulation Tool to Design Future 77 GHz JCRS-Applications

Maximilian Lubke, Yanpeng Su, Athira J. Cherian, Jonas Fuchs, Anand Dubey, Robert Weigel, Norman Franchi
2022 IEEE Access  
So called joints communications and radar sensing systems are seen as one key technology of 6G.  ...  Vehicular communication systems get more and more attention with the upcoming fifth and sixth generation.  ...  SIMULINK MODEL According to the previous sections, a DS-CDMA based system is designed.  ... 
doi:10.1109/access.2022.3170919 fatcat:frozomshk5f53fuq4roj5p74se

An Iterative Expectation-Maximization Algorithm Based Joint Estimation Approach for CDMA/OFDM Composite Radios

Tianqi Wang, Cheng Li, Hsiao-Hwa Chen
2008 IEEE Transactions on Wireless Communications  
soft decoding and an all-RAKE receiver.  ...  of a BPSK symbol is 10 −5 for an energy per received bit E b,RX = 50 nJ.  ...  S * H(X(G)|X(G c )), for all G ⊂ {1, 2, ..., N}, G = ∅.  ... 
doi:10.1109/twc.2008.070232 fatcat:37c6637lungdndzo3k5nzfiw5i

Performance Evaluation of CDMA Reverse Links With Imperfect Beamforming in a Multicell Environment Using a SimplifiedBeamforming Model

J. Yu, Y.-D. Yao, A.F. Molisch, J. Zhang
2006 IEEE Transactions on Vehicular Technology  
Reverse link capacity of a direct-sequence codedivision multiple-access (DS-CDMA) system in a multicell environment has been studied recently, and significant capacity improvements due to the use of beamforming  ...  Abstract-Reverse link capacity of a direct-sequence codedivision multiple-access (DS-CDMA) system in a multicell environment has been studied recently, and significant capacity improvements due to the  ...  ACKNOWLEDGMENT The authors would like to thank the anonymous reviewers for their valuable comments.  ... 
doi:10.1109/tvt.2006.874556 fatcat:76wjrwl4e5fhhlqg63ts7vrbcq

Introduction of Frequency-Domain Signal Processing to Broadband Single-Carrier Transmissions in a Wireless Channel

Fumiyuki ADACHI, Hiromichi TOMEBA, Kazuki TAKEDA
2009 IEICE transactions on communications  
Multi-input/multioutput (MIMO) is an important technique to improve the transmission performance. Some of the studies on MIMO/SC with FDE are introduced.  ...  Single-carrier (SC) signal transmission technique, such as DS-CDMA with coherent rake combining used in the present 3G systems [1] , provides very poor performance because of strong inter-chip interference  ...  FDE can also be applied to orthogonal multicode DS-CDMA [12] , [13] . FDE is a key technique for both MC-and DS-CDMA.  ... 
doi:10.1587/transcom.e92.b.2789 fatcat:f2t4rucw7fbcbp2phg4lrp7bsq

Advances in Underwater Acoustic Networking [chapter]

Tommaso Melodia, Hovannes Kulhandjian, Li-Chung Kuo, Emrecan Demirors
2013 Mobile Ad Hoc Networking  
The objective of this chapter is to provide an overview of the recent advances in underwater acoustic communication and networking.  ...  We briefly describe the typical communication architecture of an underwater network followed by a discussion on the basics on underwater acoustic propagation and the state of the art in acoustic communication  ...  Moreover, DS-CDMA combined with a RAKE receiver may be used to combat the multipath fading acoustic channel.  ... 
doi:10.1002/9781118511305.ch23 fatcat:zq22thfjs5aovk3pfllf53mqce

Fundamentals of Wireless Communications [chapter]

2006 Next Generation Wireless Systems and Networks  
More generally, the processes { hn [i]} n have the same statistics for different n's.  ...  It is an important mechanism to increase the capacity of CDMA systems.  ...  Orthogonal Frequency Division Multiplexing Both the single-carrier system with ISI equalization and the DS spread spectrum system with Rake reception are based on a time-domain view of the channel.  ... 
doi:10.1002/0470024569.ch2 fatcat:pwvdrx7kqvbwzoaftosigsfz2e

A Joint Denoising Learning Model for Weight Update Space–Time Diversity Method

Yu Zhang, Dan Zhang, Zhen Han, Peng Jiang
2022 Remote Sensing  
This study proposes an improved STD method with a joint noise-reduction learning model for the above issues.  ...  Finally, combining the signals on each path can improve the communication quality of the system based on the principle of the maximum signal-to-interference plus noise ratio (SINR).  ...  Thus, the model reduces the correlation between signals and suppresses MAI in the system. Table 1 . 1 The parameter settings of DS-CDMA in the simulations and lake trial.  ... 
doi:10.3390/rs14102430 fatcat:64q5z7fgkve3bai6dpd7w4exdu
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