TELK
OMNIKA
T
elecommunication,
Computing,
Electr
onics
and
Contr
ol
V
ol.
24,
No.
1,
February
2026,
pp.
14
∼
21
ISSN:
1693-6930,
DOI:
10.12928/TELK
OMNIKA.v24i1.26892
❒
14
Secur
e
h
ybrid
po
wer
-fr
equency
multiple
access
in
satellite
terr
estrial
communication
systems:
a
perf
ormance
study
Huu
Q
.
T
ran
and
V
iet-Thanh
Pham
Department
of
Electronics
and
T
elecommunication,
F
aculty
of
Electronics
T
echnology
,
Industrial
Uni
v
ersity
of
Ho
Chi
Minh
City
,
Ho
Chi
Minh
City
,
V
ietnam
Article
Inf
o
Article
history:
Recei
v
ed
Jan
3,
2025
Re
vised
Oct
29,
2025
Accepted
Dec
8,
2025
K
eyw
ords:
Hybrid
po
wer
-frequenc
y
multiple
access
Intercept
probability
Outage
probability
Satellite-terrestrial
systems
Shado
wed-Rician
f
ading
ABSTRA
CT
This
paper
in
v
estig
ates
a
secure
h
ybrid
po
wer
–frequenc
y
multiple
access
(PFMA)
frame
w
ork
for
satellite–terrestrial
communications.
By
inte
grating
po
wer
-
and
frequenc
y-domain
multiple
xing,
PFMA
achie
v
es
approximately
4
dB
lo
wer
transmit
signal-to-noise
ratio
(SNR)
than
non-orthogonal
multiple
access
(NOMA)
for
the
same
connection
outage
probabi
lity
(COP)
at
SNR
>
0
dB,
and
it
reduces
the
COP
by
up
to
30%
at
lo
w-to-medium
SNRs.
It
further
decreases
the
intercept
probability
(IP)
by
20–25%
at
P
S
=
10
dBm.
Closed-form
COP
and
IP
e
xpressions
are
deri
v
ed
under
shado
wed-Rician
f
ad-
ing
with
both
internal
and
e
xterna
l
ea
v
esdroppers
and
v
alidated
via
Monte
Carlo
simulations.
P
arameter
analysis
indicates
that
PFMA
’
s
SNR
g
ain
can
either
e
x-
tend
co
v
erage
by
60%
or
sa
v
e
37%
ener
gy
,
pro
viding
design
guidel
ines
for
6G,
satellite
IoT
,
and
emer
genc
y
communication
syst
ems.
The
single-cell
assump-
tion
points
to
future
w
ork
on
multi-cell
and
mobility
scenarios.
This
is
an
open
access
article
under
the
CC
BY
-SA
license
.
Corresponding
A
uthor:
Huu
Q.
T
ran
Department
of
Electronics
and
T
elecommunication,
F
aculty
of
Electronics
T
echnology
Industrial
Uni
v
ersity
of
Ho
Chi
Minh
City
Go
V
ap
District,
Ho
Chi
Minh
City
,
V
ietnam
Email:
tranquyhuu@iuh.edu.vn
1.
INTR
ODUCTION
Satellite–terrestrial
communication
systems
are
a
foundation
for
ne
xt-generation
netw
orks,
enabling
reliable
and
ubiquitous
connecti
vity
.
Among
multiple
access
techniques,
h
ybrid
po
wer–frequenc
y
multiple
ac-
cess
(HPFMA)
combines
po
wer
-
and
frequenc
y-domain
multiple
xing
to
enhance
spectral
ef
cienc
y
.
Ho
we
v
er
,
its
security
and
performance
can
be
hindered
by
shared
channels
and
the
comple
xities
of
h
ybrid
architectures
[1],
[2].
Existing
studies
ha
v
e
e
xplored
impro
v
ements
via
relay
protocols,
ener
gy
harv
esting,
intelligent
re-
ecting
surf
aces
(IRS),
and
spectrum
sharing
[3]-[10].
Secure
HPFMA
performance
under
realistic
f
ading
and
dual
ea
v
esdropping
scenarios
is
still
undere
xplored.
This
w
ork
lls
that
g
ap
via
a
comprehensi
v
e
performance
analysis
of
secure
HPFMA
i
n
satellite–terrestrial
systems,
focusing
on
reliability–security
trade-of
fs
and
design
insights
for
6G
and
satellite
IoT
.
T
able
1
contrasts
our
w
ork
with
prior
studies.
Unlik
e
[11]-[13],
which
focus
on
non-orthogonal
mul-
tiple
access
(NOMA)
or
simplied
f
ading,
we
deri
v
e
closed-form
connection
outage
probability
(COP)
and
intercept
probability
(IP)
for
po
wer
-f
actor
multiple
access
(PFMA)
under
shado
wed-Rician
f
ading
with
both
internal
and
e
xternal
ea
v
esdroppers.
Contrib
utions:
(i)
closed-form
COP
,
IP
,
their
asymptotics,
and
di
v
ersity
order
for
PFMA
under
shado
wed–Rician
f
ading
with
both
internal
and
e
xternal
ea
v
esdroppers;
PFMA
requires
J
ournal
homepage:
https://telk
omnika.uad.ac.id/inde
x.php/TELK
OMNIKA
Evaluation Warning : The document was created with Spire.PDF for Python.
TELK
OMNIKA
T
elecommun
Comput
El
Control
❒
15
≈
4
dB
lo
wer
SNR
than
NOMA
for
the
same
COP
at
SNR
>
0
dB;
(ii)
Monte
Carlo
v
alidation
across
di
v
erse
parameters,
sho
wing
superior
COP
o
v
er
NOMA
at
lo
w-to-medium
signal-to-noise
ratio
(SNR);
and
(iii)
pa-
rameter
study
(po
wer
,
antennas,
shado
wed–Rician
parameters,
bandwidth)
re
v
ealing
up
to
60%
co
v
erage
g
ain
or
37%
ener
gy
sa
ving.
T
able
1.
Comparison
with
related
w
orks
Ref.
Model
Metrics
Channel
Ea
v
esdropping
Limi
tations
Our
contrib
ution
[3]
NOMA
Secrec
y
rate
Rayleigh
External
No
closed-form
COP/IP
Closed-form
COP
and
IP
for
PFMA
[4]
NOMA
Outage,
er
godic
capacity
(EC)
Nakag
ami-
m
None
Simplied
f
ading
Shado
wed–Rician,
dual
ea
v
esdroppers
[13]
NOMA
COP
Rician
Internal
No
e
xternal
cas
e
Dual
ea
v
esdroppers
with
PFMA
[14]
P
artial-
NOMA
Secrec
y
rate
Rayleigh
Internal
No
frequenc
y-domain
analysis
Hybrid
po
wer–frequenc
y
,
closed-form
metrics
[15]
NOMA
IP
Rayleigh
Internal
Simpli
ed
channel
Shado
wed–Rician
with
asymptotics
Ours
PFMA
COP
,
IP
,
di
v
er
-
sity
order
(DO)
Shado
wed–Rician
Internal
and
e
x-
ternal
–
First
closed-form
COP/IP
for
PFMA;
∼
4
dB
SNR
g
ain
o
v
er
NOMA
2.
SYSTEM
MODEL
Consider
Figure
1,
where
a
satellite
(S)
emplo
ys
three
subcarriers
(
s
B
,
s
R
,
s
RB
)
to
transmit
the
con-
dential
signal
x
R
to
Ro
y
(R)
and
the
secure
signal
x
B
to
Bob
(B).
Subcarriers
s
B
and
s
R
occup
y
bandwidth
portions
(BPs)
α
B
and
α
R
,
respecti
v
ely
,
and
carry
x
B
and
x
R
using
orthogonal
multiple
access
(OMA).
Mean-
while,
a
superposition
signal
x
RB
=
√
β
R
x
R
+
√
β
B
x
B
with
po
wer
-allocation
(P
A)
f
actors
β
R
,
β
B
corresponds
to
NOMA
on
s
RB
with
BP
α
RB
.
Bob
and
Ro
y
combine
their
recei
v
ed
signals
after
baseband
reco
v
ery
without
successi
v
e
interference
cancellation
(SIC).
The
BP/P
A
rules
are
α
R
+
α
B
+
α
RB
=
1
,
β
B
+
β
R
=
1
,
and
α
RB
≤
α
B
,
α
R
.
Here,
α
Q
(
Q
∈
{
B
,
R
}
)
denotes
the
OMA
BPs,
while
α
RB
is
the
PFMA
superposition
BP;
β
B
and
β
R
are
NOMA
P
A
f
actors
.
Unless
stated
otherwise,
recei
v
ers
are
assumed
to
ha
v
e
perfect
SIC
when
required
by
a
scheme
denition.
S
a
t
e
l
l
i
t
e
(
S
)
K
a
n
t
e
n
n
a
s
R
o
y
(
R
)
B
o
b
(
B
)
R
h
B
h
B
x
R
x
B
x
R
x
B
a
n
d
w
i
d
t
h
P
o
w
e
r
RB
s
B
s
R
s
R
B
RB
B
R
F
r
e
q
u
e
n
c
y
M
a
i
n
c
h
a
n
n
e
l
S
e
c
u
r
e
c
h
a
n
n
e
l
Figure
1.
System
model
of
h
ybrid
PFMA
in
satellite–terrestrial
communication
2.1.
Pr
opagation
and
beamf
orming
Ro
y
acts
as
an
internal
ea
v
esdropper
and
may
use
SIC
to
reco
v
er
Bob’
s
message.
All
channels
h
Q
are
quasi-static
shado
wed–Rician
with
Q
∈
{
R
,
B
}
.
channel
estimation
errors
(CEEs)
render
perfect
channel
state
information
(CSI)
dif
cult;
CSI
is
estimated
via
minimum
mean
square
error
(MMSE).
The
ef
fecti
v
e
channel
is:
h
Q
=
g
†
Q
w
Q
q
L
SQ
ϑ
S
ϑ
(
θ
Q
)
(1)
Secur
e
hybrid
power
-fr
equency
multiple
access
in
satellite
terr
estrial
communication
...
(Huu
Q.
T
r
an)
Evaluation Warning : The document was created with Spire.PDF for Python.
16
❒
ISSN:
1693-6930
Here,
g
Q
∈
C
K
×
1
is
the
shado
wed–Rician
v
ector
(S
→
Q),
w
Q
∈
C
K
×
1
is
maximum
ratio
transmis-
sion
(MR
T):
w
Q
=
g
Q
∥
g
Q
∥
F
(2)
The
free-space
loss
is:
L
SQ
=
1
K
B
T
W
c
4
π
f
c
d
SQ
2
(3)
with
K
B
=
1
.
38
×
10
−
23
J/K,
T
the
noise
temperature,
W
the
bandwidth,
c
the
speed
of
light,
f
c
the
carrier
,
and
d
SQ
the
S–Q
distance
[16].
The
satellite
beam
g
ain
is:
ϑ
(
θ
Q
)
=
ϑ
Q
I
1
(
¯
ρ
Q
)
2
¯
ρ
Q
+
36
I
3
(
¯
ρ
Q
)
¯
ρ
3
Q
!
(4)
where
I
i
(
·
)
is
the
i
th-order
Bessel
function
(rst
kind),
¯
ρ
Q
=
2
.
07123
sin
θ
Q
sin
θ
Q
,
3dB
,
and
θ
Q
,
3dB
is
the
3
dB
beamwidth.
2.2.
Signal
pr
ocessing
at
Q
The
recei
v
ed
baseband
signal
at
Q
∈
{
R
,
B
}
is:
¯
y
Q
=
(
p
α
Q
P
S
L
SQ
ϑ
S
ϑ
(
θ
Q
)
x
Q
g
†
Q
w
Q
+
n
Q
,
s
Q
p
α
RB
P
S
L
SQ
ϑ
S
ϑ
(
θ
Q
)
x
RB
g
†
Q
w
Q
+
n
Q
,
s
RB
(5)
where
P
S
is
the
satellite
transmit
po
wer
and
n
Q
∼
C
N
(0
,
σ
2
Q
)
.
Dene
ν
Q
=
α
Q
+
α
RB
β
Q
and
µ
Q
=
α
Q
+
α
RB
.
The
aggre
g
ate
SINR
for
decoding
x
Q
at
Q
is
[17].
¯
γ
Q
=
ν
Q
δ
Q
∥
g
Q
∥
2
F
ν
Q
δ
Q
∥
g
Q
∥
2
F
+
µ
Q
=
ν
Q
A
Q
ν
Q
A
Q
+
µ
Q
(6)
where
ϱ
S
=
P
S
/σ
2
Q
is
the
SNR,
A
Q
=
δ
Q
∥
g
Q
∥
2
F
,
and
δ
Q
=
ϱ
S
L
SQ
ϑ
S
ϑ
(
θ
Q
)
.
After
canceling
its
o
wn
data
via
SIC,
Ro
y
tries
to
intercept
x
B
with:
ˆ
γ
R
=
α
RB
β
B
δ
R
∥
g
R
∥
2
F
µ
R
=
ν
R
A
R
µ
R
(7)
2.3.
T
err
estrial
channel
model
Assuming
i.i.d.
coef
cients,
the
probability
density
function
(PDF)
of
|
g
(
k
)
Q
|
2
(S
→
Q,
k
th
antenna)
under
shado
wed–Rician
f
ading
is:
f
|
g
(
k
)
Q
|
2
(
x
)
=
α
Q
e
−
β
Q
x
1
F
1
(
m
Q
;
1;
ϖ
Q
x
)
,
x
≥
0
(8)
with,
α
Q
=
2
b
Q
m
Q
2
b
Q
m
Q
+
Ω
Q
m
Q
.
(2
b
Q
)
,
β
Q
=
1
2
b
Q
,
ϖ
Q
=
Ω
Q
(2
b
Q
m
Q
+
Ω
Q
)
2
b
Q
Here,
Ω
Q
(LOS
po
wer),
2
b
Q
(dif
fuse
po
wer),
and
m
Q
(f
ading
se
v
erity)
follo
w
[18].
F
or
inte
ger
m
Q
,
f
|
g
(
k
)
Q
|
2
(
x
)
=
α
Q
e
−
(
β
Q
−
ϖ
Q
)
x
m
Q
−
1
X
t
=0
ζ
Q
(
t
)
x
t
,
ζ
Q
(
t
)
=
(
−
1)
t
(1
−
m
Q
)
t
ϖ
t
Q
(
t
!)
2
(9)
Using
Bank
e
y
et
al
.
[19],
the
PDF
of
A
Q
is:
TELK
OMNIKA
T
elecommun
Comput
El
Control,
V
ol.
24,
No.
1,
February
2026:
14–21
Evaluation Warning : The document was created with Spire.PDF for Python.
TELK
OMNIKA
T
elecommun
Comput
El
Control
❒
17
f
A
Q
(
x
)
=
m
Q
−
1
X
j
1
=0
·
·
·
m
Q
−
1
X
j
K
=0
Λ
Q
(
K
)
δ
∆
Q
Q
x
∆
Q
−
1
exp
−
ψ
Q
δ
Q
x
(10)
where,
Λ
Q
(
K
)
=
α
K
Q
K
Y
l
=1
ζ
Q
(
j
l
)
K
−
1
Y
u
=1
B
u
X
p
=1
j
p
+
u,
j
u
+1
+
1
!
,
∆
Q
=
K
X
l
=1
j
l
+
K
,
ψ
Q
=
β
Q
−
δ
Q
(11)
The
cumulati
v
e
distrib
ution
function
(CDF)
follo
ws
from
([18]
(8.352.6)):
F
A
Q
(
x
)
=
1
−
m
Q
−
1
X
j
1
=0
·
·
·
m
Q
−
1
X
j
K
=0
∆
Q
−
1
X
p
=0
Λ
Q
(
K
)Γ(∆
Q
)
p
!
ψ
∆
Q
−
p
Q
δ
p
Q
exp
−
ψ
Q
x
δ
Q
x
p
(12)
3.
CONNECTION
OUT
A
GE
PERFORMANCE
Let
R
B
and
R
R
be
the
tar
get
rates.
The
capacity
is
C
(
¯
γ
Q
)
=
log
2
(1
+
¯
γ
Q
)
.
The
COP
is:
COP
=
1
−
Pr(
C
(
¯
γ
R
)
>
R
R
,
C
(
¯
γ
B
)
>
R
B
)
=
1
−
[1
−
F
¯
γ
R
(
u
R
)]
[1
−
F
¯
γ
B
(
u
B
)]
(13)
where
u
Q
=
2
R
Q
−
1
.
W
e
need
F
¯
γ
Q
(
x
)
:
Theor
em
1
Under
uncorr
elated
shadowed–Rician
fading
,
the
CDF
of
¯
γ
Q
is:
F
¯
γ
Q
(
x
)
=
1
−
m
Q
−
1
X
j
1
=0
·
·
·
m
Q
−
1
X
j
K
=0
∆
Q
−
1
X
p
=0
Λ
Q
(
K
)Γ(∆
Q
)
p
!
ψ
∆
Q
−
p
Q
δ
p
Q
exp
−
ψ
Q
ς
Q
x
δ
Q
(
ε
Q
−
x
)
ς
Q
x
ε
Q
−
x
p
(14)
v
alid
for
0
≤
x
<
ε
Q
,
where
ε
Q
=
ν
Q
/
(
α
RB
β
T
)
for
T
∈
{
R
,
B
}
,
T
̸
=
Q
,
and
ς
Q
=
µ
Q
/
(
α
RB
β
T
)
Pr
oof
1
Use
F
¯
γ
Q
(
x
)
=
Pr
(
¯
γ
Q
<
x
)
and
(12)
Substituting
(14)
into
(13)
gi
v
es
the
e
xact
COP:
COP
=
1
−
Y
Q
∈{
R
,
B
}
1
−
F
¯
γ
Q
(
u
Q
)
(15)
Di
v
ersity
order
(high
SNR).
F
ollo
wing
the
high-SNR
asymptotic
e
xpansion
approach
in
[20],
from
(12),
for
ϱ
S
→
∞
,
a
Maclaurin
e
xpansion
yields
([21],
(51)).
F
∞
A
Q
(
x
)
≃
α
K
Q
x
K
K
!
δ
K
Q
(16)
Combining
with
(15),
the
asymptotic
COP
is:
COP
∞
=
α
K
Q
K
!
δ
K
Q
"
ς
R
u
R
ε
R
−
u
R
K
+
ς
B
u
B
ε
B
−
u
B
K
#
(17)
IP
=
m
B
−
1
X
j
1
=0
·
·
·
m
B
−
1
X
j
K
=0
∆
B
−
1
X
p
=0
Λ
B
(
K
)Γ(∆
B
)
p
!
ψ
∆
B
−
p
B
δ
p
B
exp
−
ψ
B
ς
B
u
B
δ
B
(
ε
B
−
u
B
)
ς
B
u
B
ε
B
−
u
B
p
(18)
Remark
1
The
closed-form
COP
and
IP
depend
on
long-term
c
hannel
statistics
(not
instantaneous
coef
-
cients),
enabling
low-cost
e
valuation
and
design
for
inte
gr
ated
satellite–terr
estrial
networks
with
perfect-CSI
baselines.
Remark
2
The
fr
ame
work
aligns
with
pr
actical
deployments
wher
e
sat
ellites
of
fer
bac
khaul
and
gap-ller
aided
access
for
indoor
handhelds,
supporting
str
eaming
and
br
oadband
connectivity
.
Secur
e
hybrid
power
-fr
equency
multiple
access
in
satellite
terr
estrial
communication
...
(Huu
Q.
T
r
an)
Evaluation Warning : The document was created with Spire.PDF for Python.
18
❒
ISSN:
1693-6930
4.
RESUL
TS
AND
DISCUSSIONS
This
section
pro
vides
numerical
simulations
to
v
erify
the
analytical
e
xpressions.
Shado
wed–Rician
parameters
for
the
S–Q
link
follo
w
[22]:
hea
vy
shado
wing
(HS)
(
m
Q
,
b
Q
,
Ω
Q
)
=
(1
,
0
.
063
,
0
.
0007)
and
a
v
erage
shado
wing
(AS)
(5
,
0
.
251
,
0
.
279)
.
Unless
otherwise
st
ated
[16],
parameters
are
K
∈
{
1
,
2
,
3
}
,
R
R
=
1
bits
per
channel
use
(BPCU),
R
B
=
0
.
5
BPCU,
β
B
=
0
.
7
,
β
R
=
0
.
3
,
α
B
=
α
R
=
(1
−
α
RB
)
/
2
,
f
c
=
2
GHz,
W
=
15
MHz,
T
=
300
K,
c
=
3
×
10
8
m/s,
d
S
Q
=
35786
km,
ϑ
S
=
5
3
.
45
dB,
ϑ
Q
=
4
.
8
dB,
θ
Q
=
0
.
8
◦
,
θ
Q
,
3dB
=
0
.
3
◦
,
bandwidth
(BW)
=
10
M
H
z
,
noisef
ig
ur
e
(
N
F
)
=
10
dB,
N
0
=
−
174
dBm/Hz.
The
noise
po
wer
is
σ
2
Q
[dBm]
=
N
0
+
10
log
10
(BW
)
+
NF
[23].
T
able
2
summarizes
k
e
y
settings.
T
able
2.
Simulation
parameters
P
arameter
V
alue
Description
K
1,
2,
3
Number
of
satellite
antennas
P
S
[
−
10
,
30]
dBm
Satellite
transmit
po
wer
α
R
B
0.1,
0.2,
0.3
BP
for
superposition
signal
m
Q
1
(HS),
5
(AS)
F
ading
se
v
erity
β
B
0.7
Po
wer
a
llocation
for
Bob
Figure
2
sho
ws
COP
vs.
P
S
(dBm).
Increasing
K
reduces
COP
via
spatial
di
v
ersity
.
PFMA
with
α
RB
∈
{
0
.
1
,
0
.
2
,
0
.
3
}
consistently
outperforms
NOMA.
At
higher
P
S
(
>
10
dBm),
COP
saturates.
Agreement
between
e
xact
and
asymptotic
curv
es
v
alidates
the
analysis.
Smaller
α
RB
further
impro
v
es
COP
by
reducing
inter
-user
interference
in
the
combined
SINRs.
The
observ
ed
≈
4
dB
SNR
g
ain
(see
Figure
3)
translates
to
∼
60%
co
v
erage
e
xtension
or
up
to
37%
po
wer
sa
ving
via
the
free-space
loss
with
traceability
in
[15].
L
S
Q
=
4
π
f
d
S
Q
c
2
(19)
Figure
3
presents
COP
vs.
P
S
for
HS
and
AS,
comparing
PFMA
and
NOMA.
Exact
(solid)
and
asymptotic
(dashed)
curv
es
match
closely
.
PFMA
consistently
outperform
s
NOMA,
with
lar
ger
g
ains
under
HS.
Under
HS
(
m
Q
=1
,
b
Q
=0
.
063
,
Ω
Q
=0
.
0007
),
COP
increases
by
up
to
20%
at
lo
w
P
S
relati
v
e
to
AS
(
m
Q
=5
,
b
Q
=0
.
251
,
Ω
Q
=0
.
279
).
Imperfect
CSI
(MMSE
with
estimation
errors)
further
de
grades
COP:
a
10%
error
-v
ariance
rise
adds
≈
5–10%
COP
,
highlighting
PFMA
’
s
reliance
on
accurate
CSI
and
its
vulnerability
to
se
v
ere
shado
wing.
Figure
4
sho
ws
COP
vs.
β
B
for
K
∈
{
1
,
2
,
3
}
and
α
RB
=
0
.
4
.
Lar
ger
K
reduces
COP
for
both
schemes,
with
PFMA
dominating
across
all
β
B
.
The
curv
es
demonstrate
the
reliability
trade-of
f
as
β
B
v
aries.
In
Figure
5
,
IP
is
plotted
vs.
P
S
for
PFMA
and
NOMA.
V
arying
α
RB
∈
{
0
.
1
,
0
.
2
,
0
.
3
}
sho
ws
PFMA
achie
v
es
lo
wer
IP
for
the
same
P
S
.
As
P
S
increases,
IP
approaches
1
for
all
schemes,
while
smaller
α
RB
benets
lo
w-
P
S
security
.
Exact
curv
es
v
alidate
the
analysis.
Future
re
search
may
consider
additional
practical
aspects,
e.g.,
hardw
are
RF
impairments
such
as
I/Q
imbalance
[24],
security–reliability
trade-of
f
with
no
n-
ideal
untrusted
relaying
[25],
and
simultaneous
secure-and-co
v
ert
transmission
under
practical
assumptions
[26].
-25
-20
-15
-10
-5
0
5
10
10
-5
10
-4
10
-3
10
-2
10
-1
10
0
Figure
2.
COP
comparison:
PFMA
vs.
NOMA
-25
-20
-15
-10
-5
0
5
10
15
10
-5
10
-4
10
-3
10
-2
10
-1
10
0
K = 1
K = 3
K = 5
Figure
3.
COP
vs.
P
S
under
dif
ferent
shado
wing;
K
=
3
,
α
RB
=
0
.
2
TELK
OMNIKA
T
elecommun
Comput
El
Control,
V
ol.
24,
No.
1,
February
2026:
14–21
Evaluation Warning : The document was created with Spire.PDF for Python.
TELK
OMNIKA
T
elecommun
Comput
El
Control
❒
19
0
0.2
0.4
0.6
0.8
1
10
-4
10
-3
10
-2
10
-1
10
0
Figure
4.
COP
vs.
β
B
,
α
RB
=
0
.
4
5
10
15
20
25
30
35
40
45
50
10
-4
10
-3
10
-2
10
-1
10
0
Figure
5.
IP
vs.
P
S
(dBm);
K
=2
,
R
R
=
R
B
=1
5.
CONCLUSION
W
e
proposed
and
analyzed
a
PFMA-based
h
ybrid
multiple
access
frame
w
ork
for
secure
sat
el-
lite–terrestrial
netw
orks.
Closed-form
COP
and
IP
e
xpressions
(with
asymptotics
and
di
v
ersity)
under
shad-
o
wed–Rician
f
ading
and
dual
ea
v
esdroppers
re
v
eal
∼
4
dB
SNR
g
ain
o
v
er
NOMA,
up
to
30%
COP
reduction,
and
20–25%
IP
reduction
at
P
S
=10
dBm.
Simulations
conrm
potential
∼
60%
co
v
erage
increase
or
up
to
37%
ener
gy
sa
ving.
Future
w
ork
will
consider
m
ulti-cell
and
mobility
scenarios,
imperfect
self-interference
mitig
ation,
optimized
BP/P
A,
multi-antenna
transcei
v
ers,
colluding
ea
v
esdroppers,
and
broader
f
ading
models.
A
CKNO
WLEDGMENT
Authors
w
ould
lik
e
to
thank
Industrial
Uni
v
ersity
of
Ho
Chi
Minh
City
(IUH)
for
the
support
of
time
and
f
acilities
for
this
study
.
FUNDING
INFORMA
TION
This
study
w
as
self-funded
by
the
authors.
A
UTHOR
CONTRIB
UTIONS
ST
A
TEMENT
This
journal
uses
the
Contri
b
ut
or
Roles
T
axonomy
(CRediT)
to
recognize
indi
vidual
author
contrib
u-
tions,
reduce
authorship
disputes,
and
f
acilitate
collaboration.
Name
of
A
uthor
C
M
So
V
a
F
o
I
R
D
O
E
V
i
Su
P
Fu
Huu
Q.
T
ran
✓
✓
✓
✓
✓
✓
✓
✓
V
iet-Thanh
Pham
✓
✓
✓
✓
C
:
C
onceptualization
I
:
I
n
v
estig
ation
V
i
:
V
i
sualization
M
:
M
ethodology
R
:
R
esources
Su
:
Su
pervision
So
:
So
ftw
are
D
:
D
ata
Curation
P
:
P
roject
Administration
V
a
:
V
a
lidation
O
:
Writing
-
O
riginal
Draft
Fu
:
Fu
nding
Acquisition
F
o
:
F
o
rmal
Analysis
E
:
Writing
-
Re
vie
w
&
E
diting
CONFLICTS
OF
INTEREST
Authors
state
no
conict
of
interest.
Secur
e
hybrid
power
-fr
equency
multiple
access
in
satellite
terr
estrial
communication
...
(Huu
Q.
T
r
an)
Evaluation Warning : The document was created with Spire.PDF for Python.
20
❒
ISSN:
1693-6930
D
A
T
A
A
V
AILABILITY
No
ne
w
data
were
generated
or
analyzed.
REFERENCES
[1]
Y
.
Gu
et
al
.,
“ISA
C
to
w
ards
6G
Satellite–T
errestrial
Communications:
Principles,
Status,
and
Prospects,
”
Electr
onics
,
v
ol.
13,
no.
7,
p.
1369,
2024,
doi:
10.3390/electronics13071369.
[2]
S.
B.
R.
T
irmizi,
Y
.
Chen,
S.
Lakshminarayana,
W
.
Feng,
and
A.
A.
Khuw
aja,
“Hybrid
Satellite–T
errestrial
Netw
orks
to
w
ard
6G:
K
e
y
T
echnologies
and
Open
Issues,
”
Sensor
s
,
v
ol.
22,
no.
21,
p.
8544,
2022,
doi:
10.3390/s22218544.
[3]
R
.
Xu,
X.
Da,
H.
Hu,
L.
Ni,
and
Y
.
P
an,
“
A
Secure
Hybrid
S
atellite-T
errestrial
Communication
Netw
ork
W
ith
AF/DF
and
Relay
Selection,
”
IEEE
Access
,
v
ol.
7,
pp.
171980–171994,
2019,
doi:
10.1109/A
CCESS.2019.2955541.
[4]
D.
T
.
Do,
A.
T
.
Le,
R.
Kharel,
A.
Silv
a,
and
M.
A.
Shattal,
“Hybrid
Satellite-T
errestrial
Relay
Netw
ork:
Proposed
Model
and
Application
of
Po
wer
Splitting
Multiple
Access,
”
Sensor
s
,
v
ol.
20,
no.
15,
p.
4296,
2020,
doi:
10.3390/s20154296.
[5]
Q.
Ngo,
T
.
K.
Phan,
A.
Mahmood,
W
.
Xiang,
“Hybrid
IRS-Assisted
Secure
Satellite-T
errestr
ial
Communications:
A
F
ast
Deep
Reinforcement
Learning
Approach,
”
Institute
of
Electrical
and
Electr
onics
Engineer
s
(IEEE)
,
Aug.
2022,
doi:
10.36227/techrxi
v
.20478438.v1.
[6]
H
.
Li,
et
al.
,
“Capacity
Upper
Bound
Analysis
of
the
Hybrid
Satellite
T
errestrial
Communication
Systems,
”
IEEE
Commun.
Lett.
,
v
ol.
20,
no.
12,
pp.
2402–2405,
2016,
doi:
10.1109/LCOMM.2016.2604387.
[7]
H
.
Li
et
al.
,
“Performance
analysis
of
the
return
link
for
the
h
ybrid
satelli
te
terrestrial
communication
systems,
”
2016
IEEE
13th
International
Confer
ence
on
Signal
Pr
ocessing
(ICSP)
,
2016,
pp.
1283-1287,
doi:
10.1109/ICSP
.2016.7878033.
[8]
K.
An
et
al.
,
“Performance
Analysis
of
Multi-Antenna
Hybrid
Satellite-T
errestrial
Relay
Netw
orks
in
the
Pres
ence
of
Interference,
”
in
IEEE
T
r
ansactions
on
Communications
,
v
ol.
63,
no.
11,
pp.
4390-4404,
No
v
.
2015,
doi:
10.1109/TCOMM.2015.2474865.
[9]
X.
Zhang,
D.
Guo,
K.
An,
G.
Zhe
ng,
S.
Chatzinotas
and
B.
Zhang,
“
Auction-Based
Multichannel
Cooperati
v
e
Spectrum
Shar
-
ing
in
Hybrid
Satell
ite-T
errestrial
IoT
Netw
orks,
”
in
IEEE
Internet
of
Things
J
ournal
,
v
ol.
8,
no.
8,
pp.
7009-7023,
2021,
doi:
10.1109/JIO
T
.2020.3037408.
[10]
P
.
Iv
ani
ˇ
s,
J.
Milojk
o
vi
´
c,
V
.
Blagoje
vi
´
c,
and
S.
Brki
´
c,
“Capacity
Analysis
of
Hybrid
Satellite–T
errestrial
Systems
with
Selection
Relaying,
”
Entr
opy
,
v
ol.
26,
no.
5,
p.
419,
2024,
doi:
10.3390/e26050419.
[11]
K.
Cao
et
al.
,
“Secure
T
ransmission
Designs
for
NOMA
Systems
Ag
ainst
Internal
and
External
Ea
v
esdropping,
”
IEEE
T
r
ansactions
on
Information
F
or
ensics
and
Security
,
v
ol.
15,
pp.
2930–2943,
2020,
doi:
10.1109/TIFS.2020.2980202.
[12]
K
.
S.
Ali,
A.
Al-Dweik,
E.
Hossain
and
M.
Chai,
“Ph
ysical
Layer
Security
of
P
artial-NOMA
and
NOMA
in
Poisson
Netw
orks,
”
in
IEEE
T
r
ansactions
on
W
ir
eless
Communications
,
v
ol.
23,
no.
6,
pp.
6562-6579,
June
2024,
doi:
10.1109/TWC.2023.3334020.
[13]
C
.-B.
Le,
D.-T
.
Do,
and
M.
V
oznak,
“Secure
transmission
in
backhaul
NOMA
systems:
A
ph
ysical
layer
security
design
with
untrusted
user
and
ea
v
esdropper
,
”
Digital
Communications
and
Networks
,
v
ol.
10,
no.
4,
pp.
1001–1013,
2024,
doi:
10.1016/j.dcan.2022.12.005.
[14]
B.
Zhuo
et
al.
,
“P
artial-NOMA
Based
Ph
ysical
Layer
Security:
F
orw
arding
Design
and
Secrec
y
Analysis,
”
in
IEEE
T
r
ansactions
on
Intellig
ent
T
r
ansportation
Systems
,
v
ol.
24,
no.
7,
pp.
7471-7484,
2023,
doi:
10.1109/TITS.2022.3166837.
[15]
Q.
Li,
D.
Xu,
K.
Na
v
aie
and
Z.
Ding,
“Co
v
ert
and
Secure
Communications
in
NOMA
Netw
orks
W
ith
Internal
Ea
v
esdropping,
”
in
IEEE
W
ir
eless
Communications
Letter
s
,
v
ol.
12,
no.
12,
pp.
2178-2182,
2023,
doi:
10.1109/L
WC.2023.3312689.
[16]
P
.
K.
Sharma,
D.
Deepthi,
and
D.
I.
Kim,
“Outage
probability
of
3-D
mobile
U
A
V
relaying
for
h
ybrid
satellite-terrestrial
netw
orks,
”
IEEE
Communications
Letter
s
,
v
ol.
24,
no.
2,
pp.
418–422,
2020,
doi:
10.1109/LCOMM.2019.2956526.
[17]
M.
W
.
Akhtar
,
A.
Mahmood,
and
M.
Gidlund,
“P
artial
NOMA
for
semi-inte
grated
sensing
and
communication,
”
in
2023
IEEE
Globecom
W
orkshops
(GC
Wkshps)
,
2023,
pp.
1129-1134,
doi:
10.1109/GCWkshps58843.2023.10464754.
[18]
I.
S.
Gradshte
yn,
I.
M.
Ryzhik,
A.
Jef
fre
y
,
Y
.
V
.
Geronimus,
M.
Y
.
Tse
ytlin,
and
Y
.
C.
Fung,
“T
able
of
Inte
grals,
Series,
and
Products,
”
J
ournal
of
Biomec
hanical
Engineering
,
v
ol.
103,
no.
1,
pp.
58–58,
1981,
doi:
10.1115/1.3138251.
[19]
V
.
Bank
e
y
,
P
.
K.
Upadh
yay
,
D.
B.
Da
Costa,
P
.
S.
Bithas,
A.
G.
Kanatas,
and
U.
S.
Dias,
“Performance
Analysis
of
Multi-Antenna
Multiuser
Hybrid
Satellite-T
errest
rial
Relay
Systems
for
Mobile
Services
Deli
v
ery
,
”
IEEE
Access
,
v
ol.
6,
pp.
24729–24745,
2018,
doi:
10.1109/A
CCESS.2018.2830801.
[20]
C.-B.
Le,
et
al.
,
“Joint
design
of
impro
v
ed
spectrum
and
ener
gy
ef
cienc
y
with
backscatter
NOMA
for
IoT
,
”
IEEE
Access
,
v
ol.
10,
pp.
7504–7519,
2022,
doi:
10.1109/A
CCESS.2021.3139118.
[21]
K.
Guo
et
al.
,
“Po
wer
Allocation
and
Performance
Ev
aluation
for
NOMA-Aided
Inte
grated
Satellite-HAP-T
errestrial
Net-
w
orks
Under
Practical
Limitations,
”
in
IEEE
Internet
of
Things
J
ournal
,
v
ol.
11,
no.
7,
pp.
13002-13017,
2024,
doi:
10.1109/JIO
T
.2023.3337124.
[22]
N.
I.
Miridakis,
D.
D.
V
er
g
ados,
and
A.
Michalas
,
“Dual-hop
communication
o
v
er
a
satellite
relay
and
shado
wed
Rician
channels,
”
in
IEEE
T
r
ansactions
on
V
ehicular
T
ec
hnolo
gy
,
v
ol.
64,
no.
9,
pp.
4031-4040,
Sept.
2015,
doi:
10.1109/TVT
.2014.2361832.
[23]
H.
Q.
T
ran
and
B.
M.
Lee,
“RIS-NOMA-assisted
short-pack
et
communication
with
direct
links,
”
J
ournal
of
King
Saud
Univer
sity
-
Computer
and
Information
Sciences
,
v
ol.
36,
no.
3,
p.
101979,
2024,
doi:
10.1016/j.jksuci.2024.101979.
[24]
X.
Li,
M.
Zhao,
Y
.
Liu,
L.
Li,
Z.
Ding,
and
A.
Nallanathan,
“Secrec
y
analysis
of
ambient
backscatter
NOMA
systems
under
I/Q
imbalance,
”
IEEE
T
r
ansactions
on
V
ehicular
T
ec
hnolo
gy
,
v
ol.
69,
no.
10,
pp.
12286–12290,
2020,
doi:
10.1109/TVT
.2020.3006478.
[25]
A.
K
uhestani,
A.
Mohammadi,
and
P
.
L.
Y
eoh,
“Security-reliability
trade-of
f
in
c
yber
-ph
ysical
cooperati
v
e
systems
with
non-
ideal
untrusted
relaying,
”
in
2018
IEEE
4th
W
orld
F
orum
on
Internet
of
Things
(WF-IoT)
,
2018,
pp.
552–557,
doi:
10.1109/WF-
IoT
.2018.8355190.
[26]
M.
F
orouzesh,
F
.
S.
Khodadad,
P
.
Azmi,
A.
K
uhestani,
and
H.
Ahmadi,
“Simultaneous
Secure
and
Co
v
ert
T
ransmissions
Ag
ainst
T
w
o
Attacks
Under
Practical
Assumptions,
”
IEEE
Internet
Things
J
ournal
,
v
ol.
10,
no.
12,
pp.
10160–10171,
2023,
doi:
10.1109/JIO
T
.2023.3237640.
TELK
OMNIKA
T
elecommun
Comput
El
Control,
V
ol.
24,
No.
1,
February
2026:
14–21
Evaluation Warning : The document was created with Spire.PDF for Python.
TELK
OMNIKA
T
elecommun
Comput
El
Control
❒
21
BIOGRAPHIES
OF
A
UTHORS
Huu
Q
.
T
ran
(Member
,
IEEE)
recei
v
ed
the
M.S.
de
gree
in
El
ectronics
Engineering
from
Ho
Chi
Minh
City
Uni
v
ersity
of
T
echnology
and
Education
(HCMUTE),
V
ietnam
in
2010.
Currently
,
he
has
been
w
orking
as
a
lecturer
at
F
aculty
of
Electronics
T
echnology
,
Industrial
Uni
v
ersity
of
Ho
Chi
Minh
City
(IUH),
V
ietnam.
He
obtained
his
Doctorate
from
the
F
aculty
of
Electrical
and
Elec-
tronics
Engineering
at
HCMUTE,
V
ietnam.
His
research
interests
include
wireless
communications,
non-orthogonal
multiple
access
(NOMA),
ener
gy
harv
esting
(EH),
wireless
cooperati
v
e
relaying
net-
w
orks,
heterogeneous
netw
orks
(HetNet),
cloud
radio
access
netw
orks
(C-RAN),
unmanned
aerial
v
ehicles
(U
A
V),
recongurable
intelligent
surf
aces
(RIS),
short-pack
et
communication
(SPC)
and
internet
of
things
(IoT).
He
can
be
contacted
at
email:
tranquyhuu@iuh.edu.vn.
V
iet-Thanh
Pham
recei
v
ed
the
Ph.D.
de
gree
in
Electronics,
Automation,
and
Control
of
Comple
x
Systems
from
the
Uni
v
ersity
of
Catania.
He
is
with
the
Industrial
Uni
v
ersity
of
Ho
Chi
Minh
City
.
His
research
interests
include
chaos,
nonlinear
control,
fractional-order
systems,
mathe-
matical
modelling,
and
applications
of
nonlinear
systems.
He
can
be
contacted
at
email:
phamviet-
thanh@iuh.edu.vn.
Secur
e
hybrid
power
-fr
equency
multiple
access
in
satellite
terr
estrial
communication
...
(Huu
Q.
T
r
an)
Evaluation Warning : The document was created with Spire.PDF for Python.