101)
One can plot the CDF undercorrelated conditions to notice the effects.
P(gR) 1
1
2r c(1 r) # e
gR
(1 r) (1 r) # e
gR
(1 r) d
b ?… 2gs
(1 r2)
a ?… 2gs
(1 r2)
Q(a, b) 3
`
b
e
1
2
(a2x2)
Io(ax) xdx
P(gs) 1 e
gs
(1 Q(a,b) Q(b,a))
We would like to present BER performance curves comparing MRC and SC (selection combining).
It is worth mentioning that various expressions exist for the theoretical BER; below a few commonly
used closed form expressions for MRC diversity combining are given. They are provided below for
sake of convenience, the first is provided by [56].
(5.102)
With the help of the following variable definition for coherent PSK modulation
(5.103)
and . If the Eb/No per antenna is required then this can be modified to be the following
. Similarly, the following definition is used for DPSK modulation performance
investigations.
(5.104)
Another commonly used form of the MRC BER is given by [39] and shown below
(5.105)
Also note that various approximations to the above two expressions exist for large and small SNR;
they are not listed here.
The first set of performance curves correspond to the BPSK family of modulation schemes and is
shown in Fig.
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