Abo Bibliothek: Guest
Digitales Portal Digitale Bibliothek eBooks Zeitschriften Referenzen und Berichte Forschungssammlungen
Telecommunications and Radio Engineering
CiteScore™: 0.23 SNIP: 0.2 SJR: 0.202

ISSN Druckformat: 0040-2508
ISSN Online: 1943-6009

Volumen 77, 2018 Volumen 76, 2017 Volumen 75, 2016 Volumen 74, 2015 Volumen 73, 2014 Volumen 72, 2013 Volumen 71, 2012 Volumen 70, 2011 Volumen 69, 2010 Volumen 68, 2009 Volumen 67, 2008 Volumen 66, 2007 Volumen 65, 2006 Volumen 64, 2005 Volumen 63, 2005 Volumen 62, 2004 Volumen 61, 2004 Volumen 60, 2003 Volumen 59, 2003 Volumen 58, 2002 Volumen 57, 2002 Volumen 56, 2001 Volumen 55, 2001 Volumen 54, 2000 Volumen 53, 1999 Volumen 52, 1998 Volumen 51, 1997

Telecommunications and Radio Engineering

DOI: 10.1615/TelecomRadEng.v69.i7.60
pages 639-652


Saniay Kumar Sharma
Dept. of Electronics and Communication Engg, Krishna Institute of Engg. and Technology, 13 KM stone, Ghaziabad-Meerut Road, Ghaziabad-201206
S. Naseem Ahmad
Department of Mathematics, Jamia Millia Islamia, New Delhi - 110025


In recent times, there has been a lot of interest in integration of voice, data and video traffic in wireless mobile communication networks. With these growing interests, wideband code division multiple access (WCDMA) has immerged as an attractive and efficient access technique. The performance of WCDMA system is deteriorated in presence of multipath fading environment. In WCDMA, the frequency selective fading destroys the orthogonility and produces multiple access interference (MAI). A Rake receiver is a usual solution in the WCDMA downlink channel. In essence, because of path diversity, a rake receiver yields reasonable system performance. However, it does not restore the orthogonality. For this, we can adopt an equalizer to restore orthogonality without significantly increasing the system complexity. The linear adaptive equalizers have proven to be the most promising method to enhance the performance of WCDMA downlink receivers. They provide an acceptable balance between system performance and system complexity and yield simple adaptive implementations and exhibit reasonable robustness with respect to the underlying assumptions. However, the adaptive equalizers do not perform well on channels having spectral nulls in the pass band. As a more attractive and efficient receiver structure, we prefer a decision feedback equalizer (DFE). A DFE exhibits better immunity against the spectral channel characteristics. The paper presents an interference cancellation based minimum mean square error (MMSE) Decision Feedback Equalizer (DFE) for wideband code division multiple access (WCDMA) in a frequency selective channel. The filter coefficients in MMSE DFE are optimized to suppress noise, intersymbol interference (ISI), and multiple access interference (MAI) with reasonable system complexity. The work includes the design of the DFE when the transmit diversity in the form of Alamouti approach is employed at the transmitter. For the above structure, we have presented the estimation of Bit Error Rate (BER) for a MMSE DFE using computer simulation experiments. The simulation process takes into consideration the effects of interference which includes additive white Gaussian noise, multipath fading, intersymbol interference (ISI) and multiple access interference (MAI). Furthermore, the performance is compared with standard adaptive linear equalizer (LE) and RAKE receiver. Numerical and simulation results show that the MMSE DFE exhibits significant performance improvement over the standard adaptive linear equalizer (LE) and RAKE receiver

SCHLÜSSELWÖRTER: code division, equalized, error, receiver