(5.138)
For sake of completeness the corresponding MMSE and MSINR array weights are given below.
(5.139)
(5.140)
The first results we present are for the M 5 antennas with P 1 CCI. We plot the BER versus
the estimator window size (N) for the MMSE, Ideal MSINR, MSINR-WSS, and genie aided knowledge
about the MSINR dimension of the noise plus interference subspaces.
Here we have two points to make: For the smaller values of the window size the plot shows how
MSINR can dramatically improve performance when compared to MMSE. Here some a priori value
of P is assumed. The second point is that the MSINR-WSS technique produced BER results very
close to the case when the rank of the RIN matrix (MSINR-SS) was known (see Fig. 5.66).
wMSINR caP
i1
s2I
i
# hIi
h*I
i
s2n
I d1
# s2d
# h
wMMSE cs2d
# h h* aP
i1
s2I
i
# hIi
h*I
i
s2n
I d1
# s2d
# h
Rxx s2d
# hh* aP
i1
s2I
i
# hIi
# h*I
i
s2n
I
PERFORMANCE IMPROVEMENT TECHNIQUES 279
Optimal Combining Performance, P = 1 CCI
M = 5 Antennas, SINR = 2.5 dB, INR = 10 dB, fd = 190 Hz
1.E??“04
1.E??“03
1.E??“02
4 5 6 7 8 9 10 11 12 13 14 15 16
Window Size (N Symbols) BER
MMSE
MSINR-SS
MSINR-WSS
Ideal MSINR
FIGURE 5.
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