Soderi, Mucchi, Hämäläinen, Piva, and Iinatti
130
The SINR at the legitimate receiver is given by [18]
M
iJAM
M
S
tr
b
tr
h
E
d N
=
=
,
2
2
0
(6.19)
where, in order to facilitate the comparisons between the two protocols, it is assumed
to transmit the same energy, that is E S . When iJAM is utilized, the γ E is still given by [17].
Figure 6.7 shows how in the iJAM the sender repeats its transmission and then halves
the data‐rate when compared with the WBPLSec proposed here. In particular, iJAM
has to transmit twice the same symbol to obtain a clean signal, whereas WBPLSec does
not. The authors compared the metrics of iJAM and WBPLSec, assuming the same
energy per symbol.
In the scenario of the iJAM and assuming that iJAM and WBPLSec have the same
bandwidth, the C s is given by
C
C
C
s
iJAM
M
E
max
w here
, ,
0
(6.20)
C M
M
iJAM
1
4
1
2
log
b it/transmission
C E
E
1
4
1
2
log
b it/transmission
As in Equation (6.18), the C s
iJAM
is conditioned to the Rayleigh channel’s coefficients,
that is h M , h E , g J , and without loss in generality in the rest of the chapter, we impose
BOB
JAMMER
JAMMER
JAMMING
N W
1
ALICE
WBPLSec
Receiver
Receiver
TX 2nd SYMBOL
TX 1st SYMBOL
WATTERMARK
BOB
JAMMING
SAME SYMBOL
TX 2 TIMES
ALICE
iJAM
Figure 6.7 Comparison between iJAM and WBPLSec.