H. Trigui et Dtm. Slock, Performance bounds for cochannel interference cancellation within the current GSM standard, SIGNAL PROC, 80(7), 2000, pp. 1335-1346
The performance of maximum-likelihood sequence estimation (MLSE) is bounded
(and often approximated well) by the matched filter bound (MFB). In this p
aper, we first show how the linearized GMSK modulation of GSM can be reform
ulated to have a real symbol constellation, leading to a two-channel aspect
due to the in-phase (I) and in-quadrature (Q) components of the received s
ignal. More channels can be added by oversampling and/or the use of multipl
e sensors (antennas, polarizations). Given this model, we present the MFB f
or MLSE single-user detection in the presence of interferers that are model
ed as colored Gaussian noise. The MLSE is assumed to employ noise correlati
on information that in general may differ from the true one (e.g. by simpli
fying spatio-temporal correlations to spatial correlations only). One of th
e conclusions is that properly taking into account the spatio-temporal corr
elation of the interference leads to much improved performance (MFB) compar
ed to purely spatial approaches. Another conclusion is that the excess band
width in GMSK provides some useful channel diversity. (C) 2000 Elsevier Sci
ence B.V. All rights reserved.