This paper considers the effect of cochannel interference on hybrid satelliteterrestrial relay network. In particular, we investigate the problem of amplifyandforward (AF) relaying in hybrid satelliteterrestrial link, where the relay is interfered by multiple cochannel interferers. The direct link between satellite and terrestrial destination is not available due to masking by surroundings. The destination node can only receive signals from satellite with the assistance of a relay node situated at ground. The satelliterelay link is assumed to follow the shadowed Rice fading, while the channels of interfererrelay and relaydestination links experience Nakagami
m
fading. For the considered AF relaying scheme, we first derive the analytical expression for the moment generating function (MGF) of the output signaltointerferenceplusnoise ratio (SINR). Then, we use the obtained MGF to derive the average symbol error rate (SER) of the considered scenario for Mary phase shift keying (MPSK) constellation under these generalized fading channels.
1. Introduction
S
atellite systems are nowadays widely used in many diverse applications such as navigation, mobile communication, broadcasting, and disaster relief. So their proper functioning in many possible scenarios is very important from both users’ and service providers’ points of view. Due to increase in population density (especially in city centers), tall/wide buildings/structures and narrow streets/roads are very common at the present time. This results in for lineofsight (LOS) communication difficult to be maintained because of shadowing and obstacles between satellite and terrestrial user
[1]

[2]
. This is also referred to as masking when LOS is lost between satellite and terrestrial user and it severely affects the indoor users being served by mobile satellite systems or in case of low satellite elevation angles.
A number of performance evaluations have been done by taking the above mentioned masking effect into consideration, especially for hybrid satelliteterrestrial cooperative networks (HSTCNs)
[1]

[2]
. Being one of the earliest performance analysis works,
[3]
gives the outage probability and the symbol error rate (SER) performance of HSTCN with multiple relays using a variable gain amplifyandforward (AF) protocol. The average SER of the fixed gain AF HSTCN with generalized (Nakagami
m
) fading channels has been derived in
[4]
. The channel between the satellite and terrestrial nodes (relay/destination) in
[3]
and
[4]
is assumed to follow the shadowed Rice land mobile satellite (LMS) model
[5]
. Different aspects of HSTCN have been studied in
[6]

[9]
. The outage performance of a HSTCN is analytically calculated in
[10]
, where satellite links are assumed to suffer from shadowed Rice fading, while the terrestrial channel suffers from Nakagami
m
fading. In
[11]
, authors derive the exact outage probability of a HSTCN, where selective decodeandforward (DF) protocol is implemented between the satellite and a terrestrial node, and a selection of the best relay terminal is performed. A slightly same system model of
[11]
is used in
[12]
to study the symbol error probability performance of a HSTCN, where in
[12]
no direct path from satellite to terrestrial (destination) node exists. In
[13]
, authors investigate the performance of AF relaying in a hybrid satelliteterrestrial free space optical cooperative link with no direct connection between satellite and ground user. The use of multiple antennas (at relay & destination) in hybrid satelliteterrestrial cooperative system is considered in
[14]
. An approximate closedform performance analysis of maximal ratio combining (MRC) in LMS channel of
[5]
is provided in
[15]
. The performance results of MRC over correlated
κ
−
μ
shadowed fading channels are obtained in
[16]
.
All of the above mentioned papers have significantly increased our knowledge of performance analysis of HSTCN, however they have concentrated on ideal case without cochannel interference (CCI). The assumption of no CCI is unrealistic nowadays due to the deployment of many wireless standards, and increased practice of reusing the spectrum resource as much as possible in traditional wireless networks causes interference at relay/destination
[17]

[20]
. Different from the previous research, recently in
[21]
the effect of CCI on SER of HSTCN has been investigated. In
[21]
, DF protocol is assumed at the terrestrial relay and the destination is corrupted by multiple CCI, both the satellitedestination and satelliterelay links undergo the shadowed Rice fading while the relaydestination link follows Rayleigh fading.
As we have mentioned above with the exception of
[21]
, the effects of multiple CCI on the performance of dualhop HSTCN have not been investigated in the open literature. Specifically, we note that the performance analysis of three node AF based hybrid satelliteterrestrial relay network (HSTRN), with either single CCI or multiple CCI at the relay has not been done yet. As a result, in this paper, for hybrid satelliteterrestrial cooperative system, we analyze the average SER of MPSKmodulated dualhop fixed gain AF relay system with multiple interferers at the relay. We study a network with no direct connection between source (satellite) and destination (terrestrial mobile user), where a relay (terrestrial) forwards the source message to the destination. The direct link between satellite and destination is unavailable due to the following propagation impairments: the blocking of signals produced by large obstacles (shadowing), severe attenuation (path loss) and multipath fading. The above mentioned wireless propagation effects are most common in satellite to terrestrial radio links, that is why we study the relay network having no direct link from satellite to terrestrial receiver. We consider generalized fading channels where the sourcerelay (satelliteearth) link follows the shadowed Rice LMS model; and the relaydestination and interferersrelay links follow Nakagami
m
fading. The system model proposed here is particularly applicable to frequencydivision relay systems
[22]

[23]
, where the relay and destination nodes experience different interference patterns. Also, the system model considered here is strongly motivated by the fact that multiaccess relay techniques deal with many sources (satellites), which use the same relay in order to deliver their data to a single destination
[24]
. We derive the exact moment generating function (MGF) of the proposed network, based on the derived MGF the average SER of the considered relay network is obtained. Extensive performance analysis in the presence of multiple interferers for MPSK modulation is done based on the expressions developed in the paper.
The remainder of this paper is organized as follows. Section 2 gives the detailed system model of considered dualhop relay network. Section 3 details the performance analysis of the proposed system model. Specifically, MGF of the cooperative link is derived and, based on this exact MGF analytical expression for SER of the cooperative link is given. Section 4 presents the detailed numerical results. Finally, Section 5 concludes this paper.
2. System Model
We consider a hybrid/integrated satelliteterrestrial communication system, where a satellite communicates with a destination node at ground through a relay node located at ground. It is assumed that satellite does not have a direct link to destination node. The communication in the system is divided into two orthogonal phases. In the first phase, the satellite sends its signal to the relay. At relay, the received signal in the presence of
n
interferers, will be
where
h
_{1}
is the channel gain between the satellite and the relay;
x
is the satellite’s transmitted symbol with
E_{s}
power;
h
_{3j}
is the channel gain between the
jth
interferer and the relay;
y_{j}
is the
jth
interferer’s transmitted symbol with
E_{ij}
power;
n
_{1}
is the zeromean additive white Gaussian noise (AWGN) at relay with
variance.
In the second phase, the relay multiplies the received signal1ywith a fixed gain
G
>0. The amplified signal is forwarded (sent) to the destination. The received signal at destination is given by
where
h
_{2}
is the channel gain between the relay and the destination, and
n
_{2}
is AWGN at destination with
variance.
The satelliterelay link is assumed to follow the shadowed Rice fading channel with the following probability density function (PDF)
[4]

[5]
where
Ω
_{1}
is the average power of LOS component, 2
b
_{1}
is the average power of the multipath component,
_{1}
F
_{1}
(
a
;
b
;
z
) is the confluent hypergeometric function [25, Eq. (9.210.1)], and 0≤
m
_{1}
≤∞ is the Nakagami parameter. For
m
_{1}
=0, (3) simplifies to the Rayleigh PDF in (4), while for
m
_{1}
=∞, it reduces to the Rice PDF. In the shadowed Rice model of
[5]
, the scattered component of the received signal follows Rayleigh distribution and LOS component follows a Nakagami
m
distribution as follows:
where 2
b
_{0}
=
E
[
X
^{2}
] is the average power of the scatter (multipath) component, Γ(·) is the gamma function
is the Nakagami parameter, and Ω=
E
[
Y
^{2}
] is the average power of the LOS component.
The relaydestination link is assumed to follow the Nakagami
m
distribution; hence, 
h
_{2}

^{2}
follows the Gamma distribution
[4]
as
where
and Ω
_{2}
denote the shape and scale parameters, respectively, of the relaydestination channel.
The interfererrelay link is assumed to follow the Nakagami
m
distribution; hence, 
h
_{3j}

^{2}
follows the Gamma distribution
[4]
as
where
and Ω
_{3j}
denote the shape and scale parameters, respectively, of the interfererrelay channel.
3. Performance Analysis
In this section, we will derive the average SER of the system model described in Section 2. We follow the standard MGF based approach
[26]
. The overall signaltointerferenceplusnoise ratio (SINR)
γ
can be written
[27]

[28]
, by using (2), as
In case of equalpower interferers (
E_{ij}
=
E_{i}
, for
j
=1,2,...,
n
), the step (a) in (8) follows from the use of the following property (summation) of Gamma distribution. When 
h
_{3j}

^{2}
has a Gamma (
m
_{3j}
, Ω
_{3}
) distribution for
j
=1,2,...,
n
(i.e., all distributions have the same scale parameter Ω
_{3}
), then,
provided that all 
h
_{3j}

^{2}
are independent. In case of arbitrarily powered (unequalpower) interferers
E_{i}
_{1}
≠
E_{i}
_{2}
≠,...,≠
E_{in}
, the step (a) in (8) follows by first applying the scaling property of the Gamma distribution, and then using the summation property of Gamma distribution. The scaling property says that, when 
h
_{3j}

^{2}
▭
Gamma
(
m
_{3j}
, Ω
_{3j}
) for
j
=1,2,...,
n
, then for any
E_{ij}
˃ 0,
E_{ij}

h
_{3j}

^{2}
▭
Gamma
(
m
_{3j}
,
E_{ij}
Ω
_{3j}
. Here, for the sake of mathematical tractability and analytical simplicity we assume that
E_{i}
_{1}
Ω
_{31}
=
E_{i}
_{2}
Ω
_{32}
= ,...,
E_{in}
Ω
_{3n}
, so that after scaling and summation operations, respectively, the result of the
denoted by
E_{i}

h
_{3}

^{2}
, still follows the Gamma distribution.
Alternatively, (8) can also be written as
On substituting
in (9), we finally get
where in (10),
is the average signaltonoiseratio (SNR), and
is the equivalent interferencetonoiseratio (INR) of interfererrelay links.
 3.1 Calculation of the MGF of the Considered System Model
The MGF of the considered system model can be written as
We pick and define the following integral from the above tripleintegral:
It can be proved in Appendix I that
Let us now define the following integral from (11) by using
I
_{1}
:
We substitute (13) and (6) in (14), and get the following
By using the method outlined in
[4]
, (15) becomes
where
c
_{1}
= ⌊
m
_{1}
⌋−1 and
e
=
m
_{1}
− ⌊
m
_{1}
⌋ for
m
_{1}
>1;
c
_{1}
=0 and
e
=
m
_{1}
−1 for
m
_{1}
≤1; and ⌊
x
⌋ denotes the largest integer not greater than
x
. By the use of Binomial expansion
in (16), we rewrite (16) as
Now we employ the following approximation (1+
x
)
^{η}
≈1+
ηx,x
<1 (17), and after applying some elementary algebraic operations (for details see Appendix II), we obtain
where,
The MGF of the considered system model can now be written, using (11) and
I
_{2}
, as
By putting (18) in (22), and after rearrangement of integrals and sums, we write the expression for MGF of our proposed system as
In (23)
It can be seen from (24)(28) that MGF contains finite and infinite integrals, which can be accurately/easily calculated in MATLAB or Mathematica.
 3.2 Calculation of SER
The SER of the considered HSTCN for MPSK constellation is given by
[4]
,
[26]
as:
where
and
Alternatively, the following accurate approximation of (29) can be used from
[29]
:
where
4. Numerical Results
This section presents the analytical and simulated results of the considered AF based HSTRN scheme using MPSK modulation over generalized fading channels. We demonstrate the expressions derived in Section 3 using numerical examples and study the effect of interference on the system’s performance. The simulated results are obtained by generating 10
^{7}
channel realizations for BPSK, QPSK and 8PSK symbols. It is assumed that relaydestination channel & interference channels follow the Nakagami
m
fading with parameters taken from
[22]
. The satelliterelay LMS channel is varied according to different shadowing conditions. The parameters of the shadowed Rice LMS model are shown in
Table 1
.
LMS channel parameters[5]
LMS channel parameters [5]
Fig. 1
shows the average SER versus SNR of the considered HSTRN, for infrequent light shadowing (satelliterelay LMS channel), with multiple values of CCI (5 dB, 0 dB and 5dB) using different MPSK modulation schemes: BPSK, QPSK and 8PSK. It is assumed that
=
; and on the xaxis of
Fig. 1
(a),
Fig. 1
(b) &
Fig. 1
(c), SNR denotes
; CCI represents
We consider the situation when relay is interfered by three equalpower interferers, i.e.,
n
= 3, and
is the CCI caused by each interferer
i
≤
n
. The values of total CCI
experienced by the source to relay link are selected as: 5 dB, 0 dB and 5dB. Any other appropriate value of CCI could be used by system designer based on specific conditions. Note that our considered system model and analysis deals with the case of arbitrary number of interferers having different transmit powers and channel parameters (already described in Section 3). Here, for simplicity and illustration purposes we consider a most common subset of this case, i.e., multiple equalpower independent interferers. The theoretical SER is plotted by using (30).
Fig. 2
presents the average SER versus SNR of the considered HSTRN, for average shadowing (satelliterelay LMS channel), with multiple values of CCI (5 dB, 0 dB and 5dB) using different MPSK modulation schemes: BPSK, QPSK and 8PSK.
Fig. 3
illustrates the average SER versus SNR of the considered HSTRN, for frequent heavy shadowing (satelliterelay LMS channel), with multiple values of CCI (5 dB, 0 dB and 5dB) using different MPSK modulation schemes: BPSK, QPSK and 8PSK. The above discussion about values of network parameters for
Fig. 1
is also valid for
Fig. 2
&
Fig. 3
. We observe from
Fig. 1
,
Fig. 2
&
Fig. 3
that simulated SER very closely follows the analytical SER, for all shadowing situations and modulations, considered in the figures; indicating the correctness of the approximations taken and derived analytical formula.
Average SER versus SNR for MPSK with CCI in infrequent light shadowing
Average SER versus SNR for MPSK with CCI in average shadowing
Average SER versus SNR for MPSK with CCI in frequent heavy shadowing
As we can see from
Fig. 1
,
Fig. 2
&
Fig. 3
, that when CCI at relay increases from 5 dB to +5 dB, there is a notable increase in average SER of the considered system for a given modulation format. We observe that the increase in SER is more prominent for higherorder modulation such as 8PSK than that of lowerorder modulation scheme of BPSK. This can be seen from
Fig. 1
,
Fig. 2
and
Fig. 3
, e.g., by comparing the curves for 8PSK and BPSK for the same value of given CCI. The same reasoning is also valid for comparing combinations of 8PSK/QPSK and QPSK/BPSK. When LMS channel experiences increase in amount of shadowing, as shown by the sequence of
Fig. 1
,
Fig. 2
and
Fig. 3
, respectively, we notice that the average SER of the HSTRN also increases correspondingly. The reader can view the effect of shadowing on the considered system by comparing the curves for particular modulation with the same given CCI from
Fig. 1
,
Fig. 2
and
Fig. 3
. We also comment here about the computational time of the expression for MFG in (23) since it contains multiple integrals. We tested in MATLAB that for different SNRs (dB), e.g. {10, 20, 30}, modern personal computer takes approximately 0.2 seconds to calculate (23). The impact of the fading severity of the relaydestination link, namely nakagami
m
_{2}
parameter, is shown in
Fig. 4
. The analysis is done for QPSK modulated HSTRN with 0 dB CCI over average shadowed LMS sourcerelay channel. It can be observed from
Fig. 4
that, with the increase in value of
m
_{2}
(decrease in amount or degree of fading), there is a corresponding decrease in SER. The impact of the fading severity of the interferersrelay links, namely nakagami
m
_{3}
parameter, is shown in
Fig. 5
. The study is done for QPSK modulated HSTRN with multiple values of
m
_{3}
amounting to different CCIs over average shadowed LMS sourcerelay channel. It can be observed from
Fig. 5
that, with the increase in value of
m
_{3}
(decrease in amount or degree of fading), there is a corresponding increase in SER. The increase in SER is due to the fact that with decrease in amount or degree of fading, the power of the interferers’ signal increases and so do the resulting CCI caused by it.
Impact of the fading severity of the relaydestination link
Impact of the fading severity of the interferersrelay links
5. Conclusion
In this paper, we have investigated the performance of AF based hybrid satelliteterrestrial cooperative system in an interference environment. We have examined the average SER of a HSTRN with multiple interferers at the relay. We have derived the average SER of the considered system under the assumption of generalized fading channels. Our analysis has shown that CCI causes significant degradation in SER performance of AF based hybrid satelliteterrestrial cooperative system. Our results are valuable in understanding how interference at the relay can degrade the overall performance, depending on different channel, interference and network parameters.
BIO
Umer Javed received the B.S. degree in electrical engineering from University of Engineering & Technology Taxila, Taxila, Pakistan, in 2006, and the M.S. degree in communications engineering from Helsinki University of Technology, Espoo, Finland, in 2009. He is currently studying for the Ph.D. degree at Shanghai Jiao Tong University, Shanghai, China.
Di He, received the Ph.D. degree in circuits and systems from Shanghai Jiao Tong University, Shanghai, China, in 2002. From 2002 to 2004, he was with the Department of Electrical and Computer Engineering, University of Calgary, Calgary, AB, Canada, as a Postdoctoral Fellow. He is currently an Associate Professor with the School of Electronic, Information and Electrical Engineering, Shanghai Jiao Tong University. His research interests are in the areas of wireless communications, nonlinear dynamics and its applications in wireless communications and positioning.
Peilin Liu, received the D.Eng. degree from the University of Tokyo, Tokyo, Japan, in 1998. In 1999, she was a Researcher with the University of Tokyo. From 1999 to 2003, she was a Senior Researcher with the Central Research Institute of Fujitsu, Tokyo. In 2003, she joined Shanghai Jiao Tong University, Shanghai, China, where she is currently a Professor with the Department of Electronic Engineering. She also directs the MediaSoC Lab and codirects the Shanghai Key Laboratory of Navigation and Locationbased Services.
Evans Barry
,
Werner Markus
,
Lutz Erich
,
Bousquet Michel
,
Corazza Giovanni E.
,
Maral Gerard
,
Rumeau Robert
,
Ferro Erina
2005
“Integration of satellite and terrestrial systems in future multimedia communications,”
IEEE Wireless Communications
12
(5)
72 
80
DOI : 10.1109/MWC.2005.1522108
Sakarellos Vasileios K.
,
Kourogiorgas Charilaos
,
Panagopoulos Athanasios D.
2014
"Cooperative Hybrid Land Mobile SatelliteTerrestrial Broadcasting Systems: Outage Probability Evaluation and Accurate Simulation,"
Wireless Personal Communication
79
(2)
1471 
1481
DOI : 10.1007/s1127701419416
Iqbal Arif
,
Ahmed Kazi M
2011
“A Hybrid SatelliteTerrestrial Cooperative Network over Non Identically Distributed Fading Channels,”
Journal of Communications
6
(7)
581 
589
DOI : 10.4304/jcm.6.7.581589
Bhatnagar Manav R.
,
Arti M.K.
2013
“Performance Analysis of AF Based Hybrid SatelliteTerrestrial Cooperative Network over Generalized Fading Channels,”
IEEE Communications Letters
17
(10)
1912 
1915
DOI : 10.1109/LCOMM.2013.090313.131079
Abdi Ali
,
Lau Wing C.
,
Alouini MohamedSlim
,
Kaveh Mostafa
2003
“A New Simple Model for Land Mobile Satellite Channels: First and SecondOrder Statistics,”
IEEE Transactions on Wireless Communications
2
(3)
519 
528
DOI : 10.1109/TWC.2003.811182
Morosi Simone
,
Jayousi Sara
,
Del Re Enrico
“Cooperative Delay Diversity in Hybrid Satellite/Terrestrial DVBSH System,”
in Proc. of IEEE Conf. on Communications
May 2327, 2010
1 
5
Ahn Do Seob
,
Kim Sooyoung
,
Kim Hee Wook
,
Park DongChul
2010
“A cooperative transmit diversity scheme for mobile satellite broadcasting systems,”
International Journal of Satellite Communications and Networking
28
(56)
352 
368
DOI : 10.1002/sat.967
Cocco G.
,
Ibars C.
,
Rio Herrero O. del
“Cooperative satellite to land mobile gapfillerless interactive system architecture,”
in Proc. of 5th Advanced satellite multimedia systems conference (asma) and the 11th signal processing for space communications workshop (spsc)
September 1315, 2010
309 
314
Paillassa Beatrice
,
Escrig Benoit
,
Dhaou Riadh
,
Boucheret MarieLaure
,
Bes Caroline
2011
“A cooperative transmit diversity scheme for mobile satellite broadcasting systems,”
International Journal of Satellite Communications and Networking
29
(6)
479 
500
DOI : 10.1002/sat.989
Sakarellos Vasileios. K.
,
Panagopoulos Athanasios. D.
“Outage performance of cooperative Land Mobile Satellite broadcasting systems,”
in Proc. of 7th European Conference on Antennas and Propagation (EuCAP)
April 812, 2013
473 
476
Sreng Sokchenda
,
Escrig Benoit
,
Boucheret MarieLaure
“Exact Outage Probability of a Hybrid Satellite Terrestrial Cooperative System with Best Relay Selection,”
in Proc. of IEEE Conf. on Communications
June 913, 2013
4520 
4524
Sreng Sokchenda
,
Escrig Benoit
,
Boucheret MarieLaure
2013
“Exact Symbol Error Probability of Hybrid/Integrated SatelliteTerrestrial Cooperative Network,”
IEEE Transactions on Wireless Communications
12
(3)
1310 
1319
DOI : 10.1109/TWC.2013.013013.120899
Bhatnagar Manav R.
,
Arti M.K.
2013
“Performance Analysis of Hybrid SatelliteTerrestrial FSO Cooperative System,”
IEEE Photonics Technology Letters
25
(22)
2197 
2200
DOI : 10.1109/LPT.2013.2282836
Arti M.K.
,
Bhatnagar Manav R.
2014
“Beamforming and Combining in Hybrid SatelliteTerrestrial Cooperative Systems,”
IEEE Communication Letters
18
(3)
483 
486
DOI : 10.1109/LCOMM.2014.012214.132738
Bhatnagar Manav R.
,
Arti M.K.
2014
“On the ClosedForm Performance Analysis of Maximal Ratio Combining in ShadowedRician Fading LMS Channels,”
IEEE Communications Letters
18
(1)
54 
57
DOI : 10.1109/LCOMM.2013.111313.131963
Bhatnagar Manav R.
2015
“On the Sum of Correlated SquaredκμShadowed Random Variables and its Application to Performance Analysis of MRC,”
IEEE Transactions on Vehicular Technology
64
(6)
2678 
2684
DOI : 10.1109/TVT.2014.2343453
Zhong Caijun
,
Jin Shi
,
Wong KaiKit
2010
“Dualhop systems with noisy relay and interferencelimited destination,”
IEEE Transactions on Communications
58
(3)
764 
768
DOI : 10.1109/TCOMM.2010.03.080156
An Kang
,
Lin Min
,
Ouyang Jian
,
Wei Heng
2014
“Beamforming in DualHop AF Relaying with Imperfect CSI and Cochannel Interference,”
Wireless Personal Communication
78
(2)
1187 
1197
DOI : 10.1007/s1127701418112
Huang Yuzhen
,
AlQahtani Fawaz
,
Zhong Caijun
,
Wu Qihui
,
Wang Jinlong
,
Alnuweiri Hussein
2014
“Performance Analysis of Multiuser Multiple Antenna Relaying Networks with CoChannel Interference and Feedback Delay,”
IEEE Transactions on Communications
62
(1)
59 
73
DOI : 10.1109/TCOMM.2013.112213.130390
Wang Jinlong
,
Huang Yuzhen
,
Zhong Caijun
,
AlQahtani Fawaz
,
Wu Qihui
,
Cheng Yunpeng
2013
“Performance analysis of interferencelimited dualhop multiple antenna AF relaying systems with feedback delay,”
EURASIP Journal on Wireless Communications and Networking 2013
284 
DOI : 10.1186/168714992013284
An Kang
,
Lin Min
,
Ouyang Jian
,
Huang Yongming
,
Zheng Gan
2014
“Symbol Error Analysis of Hybrid SatelliteTerrestrial Cooperative Networks With Cochannel Interference,”
IEEE Communications Letters
18
(11)
1947 
1950
DOI : 10.1109/LCOMM.2014.2361517
Costa Daniel Benevides da
,
Ding Haiyang
,
Ge Jianhua
2011
“InterferenceLimited Relaying Transmissions in DualHop Cooperative Networks over Nakagamim Fading,”
IEEE Communications Letters
15
(5)
54 
57
DOI : 10.1109/LCOMM.2011.032111.102112
Dohler Mischa
,
Gkelias Athanasios
,
Aghvami Hamid
2004
“Resource Allocation for FDMABased Regenerative Multihop Links,”
IEEE Transactions on Wireless Communications
3
(6)
1989 
1993
DOI : 10.1109/TWC.2004.838406
Krikidis Ioannis
,
Thompson John S.
,
McLaughlin Steve
,
Goertz Norbert
2009
“MaxMin Relay Selection for Legacy AmplifyandForward Systems with Interference,”
IEEE Transactions on Wireless Communications
8
(6)
3016 
3027
DOI : 10.1109/TWC.2009.080383
Gradshteyn I.S.
,
Ryzhik I.M.
2007
Table of Integrals, Series, and Products
7th Edition
Elsevier/Academic Press
Amsterdam
Simon Marvin K.
,
Alouini MohamedSlim
2005
Digital Communication over Fading Channels
2nd Edition
Wiley
New York
Suraweera Himal A.
,
Michalopoulos Diomidis S.
,
Yuen Chau
2012
“Performance Analysis of Fixed Gain Relay Systems With a Single Interferer in NakagamimFading Channels,”
IEEE Transactions on Vehicular Technology
61
(3)
1457 
1463
DOI : 10.1109/TVT.2012.2184311
Suraweera Himal A.
,
Garg Hari K.
,
Nallanathan A.
2010
“Performance Analysis of Two Hop AmplifyandForward Systems with Interference at the Relay,”
IEEE Communications Letters
14
(8)
692 
694
DOI : 10.1109/LCOMM.2010.08.100109
McKay Matthew R.
,
Zanella Alberto
,
Collings Iain B.
,
Chiani Marco
2009
“Error Probability and SINR Analysis of Optimum Combining in Rician Fading,”
IEEE Transactions on Communications
57
(3)
676 
687
DOI : 10.1109/TCOMM.2009.03.060521
Prudnikov A. P.
,
Brychkov Yu. A.
,
Marichev O. I.
1986
Integrals And Series Volume 1: Elementary Functions
Gordon and Breach Science Publishers
New York