Title :
NDA versus DD multipath delay estimation in wideband CDMA systems
Author :
Lohan, Elena-Simona ; Renfors, Markku
Author_Institution :
Telecommun. Lab., Tampere Univ. of Technol., Finland
Abstract :
We investigate the performance of two delay estimation algorithms, non-data aided (NDA) and decision-directed (DD), in the presence of multipath fading and additive Gaussian noise. The comparison is made assuming perfect knowledge about the amplitudes and phases of channel multipaths, in order to see the maximum achievable performance with these two algorithms. The results indicate that NDA delay estimation offers but little degradation of performance compared to DD algorithm and has the advantage of a reduced complexity and higher spectral efficiency. We also study the impact of data errors on DD delay estimation. The algorithms are applied for a downlink wideband CDMA (WCDMA) system, using Walsh spreading codes and long Gold scrambling codes
Keywords :
AWGN; Rayleigh channels; broadband networks; code division multiple access; codes; delay estimation; error statistics; land mobile radio; multipath channels; multiuser channels; spectral analysis; spread spectrum communication; AWGN; BER; DD multipath delay estimation; NDA delay estimation; QPSK data modulation; Rayleigh fading paths; WCDMA system; Walsh spreading codes; additive white Gaussian noise; channel multipath amplitude; channel multipath phase; data errors; decision-directed delay estimation; delay estimation algorithms; downlink wideband CDMA system; implementation complexity; long Gold scrambling codes; maximum achievable performance; multipath fading; non-data aided delay estimation; reduced complexity; spectral efficiency; wideband CDMA systems; Degradation; Delay estimation; Downlink; Fading; Fingers; Laboratories; Multiaccess communication; Multipath channels; Quadrature phase shift keying; Wideband;
Conference_Titel :
Personal, Indoor and Mobile Radio Communications, 2000. PIMRC 2000. The 11th IEEE International Symposium on
Conference_Location :
London
Print_ISBN :
0-7803-6463-5
DOI :
10.1109/PIMRC.2000.881597
