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Fading Mitigation with Diversity Schemes in WCDMA: Technical Review

Rajkumar Gupta, Amit chaurasia, Ashwani yadav, Vaishali V
Diversity is a technique which is used to mitigate the fading problem in wireless channel at a relatively low cost .This paper gives the review of different diversity techniques to mitigate the fading  ...  In different diversity techniques, space diversity technique is an important technique and maximum ratio combining (MRC) is the most effective technique which is a part of space diversity technique.MRC  ...  Al [32] proposed a new transmit diversity scheme using two transmit antennas and one receive antenna, the new scheme provides the same diversity order as maximal-ratio receiver combining (MRRC) with  ... 
doi:10.17148/ijireeice.2015.3542 fatcat:n6myeksddfd3tfndngugxi2rva

Performance of turbo-coded WCDMA with downlink space-time block coding in correlated fading channels

Jie Lai, N.B. Mandayam
2005 IEEE Transactions on Wireless Communications  
In this paper, we evaluate the performance of turbo coded WCDMA systems with downlink transmit diversity employing a space time block code on correlated fading channels.  ...  WCDMA systems with transmit diversity still attain performance gains compared to a single transmit antenna system.  ...  Downlink Transmit Diversity Technique Downlink transmit diversity using two transmit antennas at the base station has been adopted for the WCDMA/UMTS standards [28] .  ... 
doi:10.1109/twc.2005.844150 fatcat:kl337ovx3vcpdoet2fpxnscunq

Simulation, implementation and performance evaluation of a diversity enabled WCDMA mobile terminal

Jean-François Frigon, Ahmed M. Eltawil, Babak Daneshrad, Eugene Grayver, Yuan Li, Gennady Poberezhskiy
2007 Wireless personal communications  
Smart antenna array technology has been shown to greatly improve the performance of wireless communication systems. In this article, we describe the impact of smart antenna array processing at  ...  In the case of the two antenna diversity receivers, we assumed independent Rayleigh fading at each antenna with maximum ratio combining (MRC).  ...  Fig. 1 1 Coverage area with smart antenna receiver Fig. 3 3 Simulated BLER performance for a 12.2 Kbps connection in multipath fading Fig. 4 4 Performance comparison of MRC and LMS combining algorithms  ... 
doi:10.1007/s11277-007-9286-z fatcat:ilnprilm3rgvrpn5ur7lpshwpu

Design and Implementation of a Baseband WCDMA Dual-Antenna Mobile Terminal

Jean-Franois Frigon, Ahmed M. Eltawil, Eugene Grayver, Alireza Tarighat, Hanli Zou
2007 IEEE Transactions on Circuits and Systems I Fundamental Theory and Applications  
Spatial diversity processing mitigates wireless channel impairments and is a key enabling technology for WCDMA to support high quality of service at high data rates and capacity.  ...  The receiver design, which takes advantage of diversity benefits in several blocks, is described in detail.  ...  RAKE Receiver and Combiner The dual-antenna WCDMA receiver combines time processing of multipaths with spatial processing of the signal received on both antennas to improve the system performance.  ... 
doi:10.1109/tcsi.2006.887620 fatcat:lsuzwta6fnerfih2ypkoiggvbq

A New Combination of RAKE Receiver and Adaptive Antenna Array Beamformer for Multiuser Detection in WCDMA Systems

Shahriar Shirvani-Moghaddam, Hajar Sadeghi
2011 International Journal of Antennas and Propagation  
The aim of this paper is to combine smart antenna beamforming and RAKE receiver in wideband code division multiple access (WCDMA).  ...  The proposed method combines spatial diversity as well as temporal diversity to improve the performance and overcome both interferences and multipath fading.  ...  Acknowledgment The authors would like to thank anonymous reviewers of International Journal of Antennas and Propagation (IJAP) for their careful reviews of the paper.  ... 
doi:10.1155/2011/208301 fatcat:5rmpuhjvwvbmbhnu7egx4qt3va

BER Performance of Space-Time Coded MMSE DFE for Wideband Code Division Multiple Access (WCDMA)

Sanjay Kumar SHARMA, S. Naseem AHMAD
2009 International Journal of Communications, Network and System Sciences  
With these growing interests, WCDMA has immerged as an attractive access technique. The performance of WCDMA system is deteriorated in presence of multipath fading environment.  ...  The paper presents space-time coded minimum mean square error (MMSE) Decision Feedback Equalizer (DFE) for wideband code division multiple access (WCDMA) in a frequency selective channel.  ...  The combination of MUD and receive diversity techniques has been proposed in [2, 3] . In third generation WCDMA systems, the processing transmit gain may be very small.  ... 
doi:10.4236/ijcns.2009.24030 fatcat:vsvhmt5oonf6je4mn2am43eode

A New Approach to Joint Full-Rate STBC and Long-Code WCDMA for Four Transmit Antenna MIMO Systems

Cheng Shen, Jonathon Chambers
2006 2006 8th international Conference on Signal Processing  
Citation: CHENG, S. and CHAMBERS, J., 2006. A new approach to joint fullrate STBC and long-code WCDMA for four transmit antenna MIMO systems.  ...  Recently, many works have appeared on signal processing and modulation techniques for transmit diversity over fading channels in order to exploit the large capacity available in a multi-antenna system  ...  We will consider a quasi-static time-varying channel for each transmit and receiver antenna pair, i.e., that the channel doesn't change in a slot period.  ... 
doi:10.1109/icosp.2006.345790 fatcat:j2ob7egupncplcgxznhmxksr3y

2005 Index

2005 IEEE Transactions on Vehicular Technology  
., receiver design. Vehkapera, M., + , T-VT May 05 1042-1055 transmit antenna selection/maximal-ratio combining, Rayleigh fading channels.  ...  ., + , T-VT Jul 05 1352-1360 transmit antenna selection/maximal-ratio combining, Rayleigh fading channels.  ...  Ding-Bing Lin, + , T-VT Jul 05 1447-1454 efficient support of QoS, fading channel, utilizing multiuser diversity.  ... 
doi:10.1109/tvt.2005.863647 fatcat:7ftwl4fyt5adfatoufxaoldhai

Coherent Code Tracking for Spatial Transmit Diversity DS-CDMA Systems

Garrey W. Rice, Iain G. Stirling, R.W. Stewart
2005 EURASIP Journal on Advances in Signal Processing  
When DS-CDMA-based technology is deployed in typical macro-and microcell environments, multipath diversity and spatial diversity may be exploited simultaneously by a 2D RAKE receiver.  ...  We investigate the use of coherent and noncoherent techniques for tracking the timing parameters of each multipath component.  ...  Exploiting spatial transmit diversity A suggestion for noncoherent timing error detection which combines the signals from multiple receive antennas is given in [10] .  ... 
doi:10.1155/asp.2005.2739 fatcat:q4u5uu3lfzad7d2g7quvgiwihu

Wideband code division multiple access

L.B. Milstein
2000 IEEE Journal on Selected Areas in Communications  
In this paper, we discuss those basic characteristics of WCDMA waveforms that make them attractive for high data rate transmission over wireless and mobile channels.  ...  We then discuss how some of the waveforms being considered for cellular WCDMA systems differ from those in use in the narrowband CDMA cellular system, and emphasize, as an example, multicarrier CDMA.  ...  Thus, the need for multiple transmit antennas to provide spatial diversity in WCDMA is less than that in NCDMA.  ... 
doi:10.1109/49.864000 fatcat:tmhmvxsghnh35fglq636nfdyii

Smart antennas for wireless systems

J.H. Winters
1998 IEEE personal communications  
receive signal-to-noise ratio for a given BER averaged over fading -Depends on BER -Gain for M=2 vs. diversity gain may be smaller with RAKE receiver in CDMA DIVERSITY zero-mean Gaussian random variables  ...  , they also provide: • M-fold multipath diversity gain • With M Tx antennas (MIMO), M-fold data rate increase in same channel with same total transmit power Switched Multibeam Antenna Adaptive Antenna  ...  ADAPTIVE ARRAYS IN EDGE Spatial-Temporal processing using DDFSE for interference suppression Issues: tracking, dual antenna terminals  ... 
doi:10.1109/98.656155 fatcat:7ojfmdouqfevdh6tsbhtpwzf2e

Combined Beamforming And Channel Estimation In Wcdma Communication Systems

Nermin A. Mohamed, Mohamed F. Madkour
2007 Zenodo  
In this paper, we present new methods to combine interference suppression together with channel estimation when using multiple receiving antennas by using adaptive signal processing techniques.  ...  We address the problem of joint beamforming and multipath channel parameters estimation in Wideband Code Division Multiple Access (WCDMA) communication systems that employ Multiple-Access Interference  ...  The kth user signal is transmitted through a Rayleigh multipath fading (with L paths) channel to a receiver that consists of M antenna elements.  ... 
doi:10.5281/zenodo.1075318 fatcat:b2yc4habyfd5zex6rxtjcj42au

Performance analysis of space-time transmitter diversity techniques for WCDMA using long range prediction

S. Guncavdi, A. Duel-Hallen
2005 IEEE Transactions on Wireless Communications  
We employ the long range fading prediction algorithm to enable transmitter diversity techniques for rapidly time varying multipath fading channels.  ...  In particular, Selective Transmit Diversity, Transmit Adaptive Array and Space-Time Pre-RAKE techniques are compared.  ...  We investigate the Space-Time Pre-RAKE (STPR) diversity combining method for multipath fading channels and compare it with the previously studied techniques such as STD and Tx AA.  ... 
doi:10.1109/twc.2004.840222 fatcat:iepuratk5rf5lilbkv4a2dt3ia

Dynamic QoS Guarantee with Repeater in Power Controlled WCDMA Urban Environment [chapter]

Mohammad N. Patwary, Predrag Rapajic, Ian Oppermann
2003 Mobile and Wireless Communications  
We propose to use repeater as a reliable alternate in this critical channel condition. On the other hand ARQ scheme is efficient only for non-real time communication.  ...  In dense urban environment, the possibility of signal reception failed (receiving NAK) repeatedly at the receiving end of the conventional ARQ scheme is nonzero even if with strong FEC as 113 turbo code  ...  A set of antenna diversity for rural macro cell and urban microcell have been shown with array antenna in defuse channel model in [3] .  ... 
doi:10.1007/978-0-387-35618-1_17 dblp:conf/ifip6-8/PatwaryRO02 fatcat:5qedvavhwrdrvawwrnx7z2jcuu

Blind adaptive space-time multiuser detection with multiple transmitter and receiver antennas

D. Reynolds, Xiaodong Wang, H.V. Poor
2002 IEEE Transactions on Signal Processing  
We also develop blind adaptive implementations for the two transmit/two receive antenna case for synchronous CDMA in flatfading channels and for asynchronous CDMA in fading multipath channels.  ...  In particular, much recent work has been done on space-time processing in which multiple transmit/receive antennas are used in conjunction with coding to exploit spatial diversity.  ...  Then, we develop blind adaptive implementations of the two transmit/two receive antenna configuration for synchronous CDMA in flat-fading channels and for asynchronous CDMA in fading multipath channels  ... 
doi:10.1109/tsp.2002.1003052 fatcat:cb7syu4vczdztp7w27mf7pkuti
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