Dual Antenna LMMSE Equalization using Bad Urban Measured Channel Data in HSDPA Multicode Transmission
Conference: PIMRC 2005 - 16th Annual IEEE International Symposium on Personal Indoor and Mobile Radio Communications
09/11/2005 - 09/14/2005 at Berlin, Germany
Proceedings: PIMRC 2005
Pages: 5Language: englishTyp: PDFPersonal VDE Members are entitled to a 10% discount on this title
Mattila, Jari (Nokia Research Center, PO Box 407, 00045 Nokia Group, Helsinki, Finland)
This paper discusses WCDMA mobile terminal receivers that employ dual-antenna LMMSE equalization in High Speed Downlink Packet Access (HSDPA) multicode transmission. The effects of fast fading and non-idealities, like branch power difference and correlation between the antennas, are taken into account by using measured impulse responses in the link simulations. Tbe channel data correspond to difficult "bad urban" cellular environments. The simulation model includes the link adaptation features of future HSDPA terminals. The simulation results show that space-time equalization in a terminal handset provides significant performance gains over conventional RAKE. Dual antennas clearly outperform a single antenna both in chip-level equalization and conventional RAKE reception. It was noted that the equalizer length easily becomes a problem in the large delay spread channel. We also sbow how the measured channel data can be utilized in the link performance analysis.