INVESTIGADORES
CORRAL BRIONES graciela
congresos y reuniones científicas
Título:
A simple technique to improve performance of RAKE receivers in CDMAPCS indoor systems
Autor/es:
CARLO A. MARQUES; MARIO R. HUEDA; GRACIELA CORRAL BRIONES; CARMEN E. RODRIGUEZ
Lugar:
New Orleans, LA, USA
Reunión:
Conferencia; 1999 IEEE Wireless Communications and Networking Conference, 1999. WCNC.; 1999
Resumen:
In channels where the delay spread is smaller than the chip
interval, spread spectrum signals do not give rise to path diversity,
thus a classical maximal ratio combiner (MRC)-RAKE receiver sets to
unity the number of branches. In this situation, MRC-RAKE receivers with
resolution reduction (RR) of the diversity branches may be used to
significantly improve performance in the forward link of DS-CDMA systems
(Yang 1995). As a result of the use of RR techniques, the noise
components at the finger outputs are correlated. It has been shown that
the MRC is suboptimal in the presence of correlated noise components. In
this paper, a minimum mean squared error combiner (MMSEC) RAKE receiver
with RR is proposed. The performance of the RAKE receiver with two
branches is studied by means of theoretical analysis and computer
simulations. To allow a simple practical implementation, a suboptimal
structure of the MMSEC is also proposed. Frame error rate (FER) is
obtained by using a simulation system based on the forward link of the
digital cellular standard IS-95 in a typical indoor radio channel. Our
results show that this new receiver scheme can achieve a gain of 3.6 dB
over a conventional MRC-RAKE receiver at an FER of 0.01, with small
increase in complexity