3 research outputs found
Joint array combining and MLSE for single-user receivers in multipath Gaussian multiuser channels
The well-known structure of an array combiner along with a maximum likelihood sequence estimator (MLSE) receiver
is the basis for the derivation of a space-time processor presenting
good properties in terms of co-channel and intersymbol interference
rejection. The use of spatial diversity at the receiver front-end
together with a scalar MLSE implies a joint design of the spatial
combiner and the impulse response for the sequence detector. This
is faced using the MMSE criterion under the constraint that the
desired user signal power is not cancelled, yielding an impulse response
for the sequence detector that is matched to the channel and
combiner response. The procedure maximizes the signal-to-noise
ratio at the input of the detector and exhibits excellent performance
in realistic multipath channels.Peer Reviewe
Block channel equalization in the presence of a cochannel interferent signal
Novel algorithms for block equalization of M-ary phase shift keying (PSK) signals transmitted over multipath fading channels in the presence of an interferent cochannel signal are introduced and analyzed. The algorithms exploit the intrinsic statistical properties of cochannel interference (CCI) in order to mitigate its effects. Both linear and decision feedback equalizers (DFE's) are derived under the assumption that the overall channel impulse responses of both the useful and the inteferent signal are known, Simulation results show that: a) whereas zero-forcing block equalizers yield a large noise enhancement effect, a minimum mean-square block DFE (MMSE-BDFE) can efficiently compensate for the distortion in the useful channel and reduce the effect of CCI at the same time and b) MMSE-BDFE's outperform conventional DFE's, at least in the idealized conditions of our analysis