Transmit processing techniques based on switched interleaving and limited feedback for interference mitigation in multi-antenna MC-CDMA systems
Résumé
In this work, we propose transmit processing
techniques based on novel switched interleaving, chip-wise
linear precoding, and limited feedback for both downlink and
uplink multi-carrier code division multiple access (MC-CDMA)
multiple antenna systems. We propose transceiver structures
with switched interleaving, linear precoding and detectors
for both uplink and downlink. In the novel schemes, a set
of possible chip-interleavers are constructed and prestored at
both the base station (BS) and mobile stations (MSs). For the
downlink, a new hybrid transmit processing technique based
on switched interleaving and chip-wise precoding is proposed
to suppress the multiuser interference (MUI). The BS and
MSs are also equipped with another codebook of quantized
downlink channel state information (CSI). Each MS quantizes
its own downlink CSI and feeds back the index to the BS by a
low-rate feedback channel or link, then the selection function
at the BS determines the optimum interleaver based on all
users? quantized CSIs to transmit signals. Moreover, a transmit
processing technique for the uplink of multiple antenna MCCDMA
systems requiring very low rate of feedback information
is also proposed. Codebook design methods for both interleavers
and quantized CSI are also proposed. Simulation results show
that the performance of the proposed techniques is significantly
better than prior art.