Title :
Performance enhancement of differential UWB autocorrelation receivers under ISI
Author :
Pausini, Marco ; Janssen, Gerard J M ; Witrisal, Klaus
Author_Institution :
Wireless & Mobile Commun. Group, Delft Univ. of Technol., Netherlands
fDate :
4/1/2006 12:00:00 AM
Abstract :
The autocorrelation receiver (AcR) is a suboptimum, low-complexity receiver architecture particularly suited to ultra-wideband (UWB) communication systems. As the bit rate increases, interference among pulses due to multipath propagation causes serious impairments of the AcR´s performance. To mitigate this effect, we propose an appropriate design of the chip code and of the delay hopping (DH) code. We provide conditions to be satisfied by the DH code in order to reduce the nonlinear intersymbol interference (ISI) and the bias term, which are peculiar nuisance parameters of autocorrelation receivers. By extending the length of the chip code, we show that Np transmitted pulses per symbol can be employed to suppress the average linear ISI of Np-1 previous symbols. Simulated results confirm the performance improvement in terms of bit-error rate. However, in previous work it has been shown that the noise power linearly increases with Np. Although a large number of pulses per symbol is favorable for ISI mitigation, we show that the transmission of a single pulse minimizes the probability of error, for bit rates lower than an upper bound depending on the channel root mean-square delay spread and on the noise power.
Keywords :
correlation methods; differential detection; error statistics; intersymbol interference; mean square error methods; multipath channels; radio receivers; radiowave propagation; ultra wideband communication; DH; ISI; delay hopping code; differential UWB autocorrelation receiver; error probability; multipath propagation; nonlinear intersymbol interference; root mean-square delay spread; ultrawideband communication system; Autocorrelation; Bit rate; Channel estimation; DH-HEMTs; Delay; Fading; Intersymbol interference; Multipath channels; RAKE receivers; Ultra wideband technology; Autocorrelation receiver; chip and delay hopping (DH) code; intersymbol interference (ISI); number of pulses per symbol; ultra-wideband (UWB);
Journal_Title :
Selected Areas in Communications, IEEE Journal on
DOI :
10.1109/JSAC.2005.863845