Lixia Xiao
Publications
Xiao Lixia, Xiao Pei, Xiao Yue, Hemadeh Ibrahim, Mohamed Abdelrahim, Hanzo Lajos (2018) Bayesian Compressive Sensing Assisted Space Time Block Coded Quadrature Spatial Modulation,IEEE Transactions on Vehicular Technology67(10)pp. 10044-10048 Institute of Electrical and Electronics Engineers (IEEE)
A novel Multiple-Input and Multiple-
Output (MIMO) transmission scheme termed as Space-
Time Block Coded Quadrature Spatial Modulation
(STBC-QSM) is proposed. It amalgamates the concept
of Quadrature Spatial Modulation (QSM) and Space-
Time Block Coding (STBC) to exploit the diversity
benefits of STBC relying on sparse Radio Frequency
(RF) chains. In the proposed STBC-QSM scheme, the
conventional constellation points of the STBC structure
are replaced by the QSM symbols, hence the
information bits are conveyed both by the antenna
indices as well as by conventional STBC blocks. Furthermore,
an efficient Bayesian Compressive Sensing
(BCS) algorithm is developed for our proposed STBCQSM
system. Both our analytical and simulation results
demonstrated that the proposed scheme is capable
of providing considerable performance gains over the
existing schemes. Moreover, the proposed BCS detector
is capable of approaching the Maximum Likelihood
(ML) detector?s performance despite only imposing a
complexity near similar to that of the Minimum Mean
Square Error (MMSE) detector in the high Signal to
Noise Ratio (SNR) regions.
Xiao Lixia, Xiao Pei, Xiao Y, Wu C, Nguyen Hung, Hemadeh Ibrahim, Hanzo L (2018) Transmit Antenna Combination Optimization for Generalized Spatial Modulation Systems,IEEE Access6pp. 41866-41882 IEEE
Generalized Spatial Modulation (GSM),
where both the Transmit Antenna Combination (TAC)
index and the Amplitude Phase Modulation (APM)
symbols convey information, is a novel low-complexity
and high efficiency Multiple Input Multiple Output
(MIMO) technique. In Conventional GSM (C-GSM),
the legitimate TACs are selected randomly to transmit
the APM symbols. However, the number of the TACs
must be a power of two, hence the excess TACs are discarded,
resulting in wasting some resource. To address
these issues, in this paper, an optimal TAC set-aided
Enhanced GSM (E-GSM) scheme is proposed, where
the optimal TAC set is selected with the aid of the
Channel State Information (CSI) by maximizing the
Minimum Euclidean Distance (MED). Furthermore,
a Hybrid Mapping GSM (HM-GSM) scheme operating
without CSI knowledge is investigated, where
the TAC selection and bit-to-TAC mapping are both
taken into consideration for optimizing the Average
Hamming Distance (AHD). Finally, an Enhanced High
Throughput GSM (E-HT-GSM) scheme is developed,
which makes full use of all the TACs. This scheme is
capable of achieving an extra one bit transmission rate
per time slot. Moreover, rotated phase is employed
and optimized for the reused TACs. Our simulation
results show that the proposed E-GSM system and
HM-GSM system are capable of outperforming the CGSM
system. Furthermore, the E-HT-GSM system is
capable of obtaining one extra bit transmission rate per
time slot compared to the C-GSM system.
He Chang, Cao Aijun, Xiao Lixia, Zhang Lei, Xiao Pei, Nikitopoulos Konstantinos (2019) Enhanced DCT-OFDM System With Index Modulation,IEEE Transactions on Vehicular Technology Institute of Electrical and Electronics Engineers (IEEE)
Discrete cosine transform (DCT) based orthogonal
frequency division multiplexing (OFDM), which has double number
of subcarrier compared to the classic discrete fourier transform
(DFT) based OFDM (DFT-OFDM) at the same bandwidth,
is a promising high spectral efficiency multicarrier techniques
for future wireless communication. In this paper, an enhanced
DCT-OFDM with index modulation (IM) (EDCT-OFDM-IM) is
proposed to further exploit the benefits of the DCT-OFDM and
IM techniques. To be more specific, a pre-filtering method based
DCT-OFDM-IM transmitter is first designed and the non-linear
maximum likelihood (ML) is developed for our EDCT-OFDM-IM
system. Moreover, the average bit error probability (ABEP) of the
proposed EDCT-OFDM-IM system is derived, which is confirmed
by our simulation results. Both simulation and theoretical results
are shown that the proposed EDCT-OFDM-IM system exhibits
better bit error rate (BER) performance over the conventional
DFT-OFDM-IM and DCT-OFDM-IM counterparts.
Xiao Lixia, Xiao Pei, Xiao Yue, Wu Chaowu, Mi De, Hemadeh Ibrahim A. (2019) Rectangular Differential OFDM with index modulation,Proceedings of the 2019 IEEE 89th Vehicular Technology Conference: VTC2019-Spring Institute of Electrical and Electronics Engineers (IEEE)
Orthogonal Frequency Division Multiplexing
(OFDM) with Index Modulation (OFDM-IM),
which conveyed information bits via the activated indices
and constellation symbols is a promising technique
in the next wireless communications. In the OFDM-IM
scheme, only part of subcarriers are activated to transmit
information, the inactive subcarriers transmit zero
symbols, so that the conventional differential coding is
not suitable for the adjacent subcarriers. In order to
address this issue, in this paper, a novel Rectangular
Differential OFDM-IM (RD-OFDM-IM) scheme is proposed
to exploit the benefits of OFDM-IM dispensing
with Channel State Information (CSI). In the proposed
RD-OFDM-IM scheme, N subcarriers are partitioned
into G subblocks and index modulation is employed in
each subblock first. Then rectangular differential coding
is invoked during two adjacent subblocks, so that nocoherent
detection can be employed for the proposed
RD-OFDM-IM scheme. Simulation results are shown
that the proposed RD-OFDM-IM scheme is capable
of providing considerable performance gain over conventional
Differential OFDM (D-OFDM) scheme with
lower Peak Average Power Ratio (PAPR).
He Chang, Cao Aijun, Xiao Lixia, Zhang Lei, Xiao Pei, Nikitopoulos Konstantinos (2019) Index modulation assisted DCT-OFDM with Enhanced Transceiver Design,Proceedings of the 53rd IEEE International Conference on Communications (IEEE ICC 2019) Institute of Electrical and Electronics Engineers (IEEE)
An index modulation (IM) assisted Discrete Cosine
Transform based Orthogonal Frequency Division Multiplexing
(DCT-OFDM) with Enhanced Transmitter Design (termed as
EDCT-OFDM-IM) is proposed. It amalgamates the concept
of Discrete Cosine Transform assisted Orthogonal Frequency
Division Multiplexing (DCT-OFDM) and Index Modulation (IM)
to exploit the design freedom provided by the double number
of available subcarrier under the same bandwidth. In the
proposed EDCT-OFDM-IM scheme, the maximum likelihood
(ML) detector used for symbol bits and index bits recovering
is derived and the sophisticated designing guidelines for EDCTOFDM-IM are provided. Based on the derived pairwise error
event probability, a theoretical upper bound on the average biterror probability (ABEP) of EDCT-OFDM-IM is provided over
multipath fading channels. Furthermore, the maximum peak-toaverage power ratio (PAPR) of our proposed EDCT-OFDM-IM
scheme is derived and compared to than the general Discrete
Fourier Transform (DFT) based OFDM-IM counterpart.
Xiao Lixia, Xiao Pei, Xiao Yue, Haas Harald, Mohamed Abdelrahim, Hanzo Lajos (2019) Compressive Sensing Assisted Generalized Quadrature Spatial Modulation for Massive MIMO systems,IEEE Transactions on Communicationspp. 1-1 Institute of Electrical and Electronics Engineers (IEEE)
A novel Multiple-Input and Multiple- Output (MIMO) transmission scheme termed as Generalized Quadrature Spatial Modulation (G-QSM) is proposed. It amalgamates the concept of Quadrature Spatial Modulation (QSM) and spatial multiplexing for the sake of achieving a high throughput, despite relying on low number of Radio Frequency (RF) chains. In the proposed G-QSM scheme, the conventional constellation points of the spatial multiplexing structure are replaced by the QSM symbols, hence the information bits are conveyed both by the antenna indices as well as by the classic Amplitude/Phase Modulated (APM) constellation points. The upper bounds of the Average Bit Error Probability (ABEP) of the proposed G-QSM system in high throughput massive MIMO configurations are derived. Furthermore, an Efficient Multipath Orthogonal Matching Pursuit (EMOMP) based Compressive Sensing (CS) detector is developed for our proposed G-QSM system. Both our analytical and simulation results demonstrated that the proposed scheme is capable of providing considerable performance gains over the existing schemes in massive MIMO configurations.
Xiao Lixia, Xiao Pei, Xu Chao, Hemadeh Ibrahim A., Mi De, Hao Wanming (2019) Generalized Space Time Block Coded Spatial Modulation Systems,Proceedings of the 2019 Annual IEEE International Symposium on Personal, Indoor and Mobile Radio Communications (IEEE PIMRC 2019) Institute of Electrical and Electronics Engineers (IEEE)
In this paper, Generalized Space-Time
Block Coded Spatial Modulation (GSTBC-SM) is proposed
for Multiple-Input and Multiple-Output (MIMO)
system, which can be extended into an arbitrary
even number of Transmit Antennas (TAs). The proposed
GSTBC-SM scheme employs the hybrid concepts
of Generalized Space-Time Block Coding (GSTBC)
and Spatial Modulation (SM) to further exploit
the diversity benefits of GSTBC using sparse Radio
Frequency (RF) chains. To be more specific, the information
bits are divided into Nu groups and each
group is modulated by SM scheme. Finally, the Nu
symbols are invoked for GSTBC structure. In order to
demonstrated the advantages of our proposed GSTBCSM
schemes, the theoretical Average Bit Error Probability
(ABEP) of our proposed GSTBC-SM is derived.
Both our analytical and simulation results demonstrated
that the proposed GSTBC-SM scheme is capable
of providing considerable performance gains over the
corresponding GSTBC schemes at the same transmit
rate associated with the same number of RF chains.
Xiao Lixia, Xiao Pei, Liu Zilong, Yu Wenjua, Haas Harald, Hanzo Lajos (2020) A Compressive Sensing Assisted Massive SM-VBLAST System: Error Probability and Capacity Analysis,IEEE Transactions on Wireless Communicationspp. 1-1 IEEE
The concept of massive spatial modulation (SM) assisted vertical bell labs space-time (V-BLAST) (SM-VBLAST) system [1] is proposed, where SM symbols (instead of conventional constellation symbols) are mapped onto the VBLAST structure. We show that the proposed SM-VBLAST is a promising massive multiple input multiple output (MIMO) candidate owing to its high throughput and low number of radio frequency (RF) chains used at the transmitter. For the generalized massive SM-VBLAST systems, we first derive both the upper bounds of the average bit error probability (ABEP) and the lower bounds of the ergodic capacity. Then, we develop an efficient error correction mechanism (ECM) assisted compressive sensing (CS) detector whose performance tends to achieve that of the maximum likelihood (ML) detector. Our simulations indicate that the proposed ECM-CS detector is suitable both for massive SM-MIMO based point-to-point and for uplink communications at the cost of a slightly higher complexity than that of the compressive sampling matching pursuit (CoSaMP) based detector in the high SNR region.
Hemadeh Ibrahim, Xiao Pei, Kabiri Yasin, Xiao Lixia, Fusco Vincent (2020) Polarization Modulation Design for Reduced RF
Chain Wireless,IEEE Transactions on Communications Institute of Electrical and Electronics Engineers
In this treatise, we introduce a novel
polarization modulation (PM) scheme, where we
capitalize on the reconfigurable polarization antenna
design for exploring the polarization domain
degrees of freedom, thus boosting the system
throughput. More specifically, we invoke the
inherent properties of a dual polarized (DP) antenna
for transmitting additional information carried
by the axial ratio (AR) and tilt angle of
elliptic polarization, in addition to the information
streams transmitted over its vertical (V) and
horizontal (H) components. Furthermore, we propose
a special algorithm for generating an improved
PM constellation tailored especially for
wireless PM modulation. We also provide an analytical
framework to compute the average bit error
rate (ABER) of the PM system. Furthermore, we
characterize both the discrete-input continuousoutput
memoryless channel (DCMC) capacity and
the continuous-input continuous-output memoryless
channel (CCMC) capacity as well as the upper
and lower bounds of the CCMC capacity. The
results show the superiority of our proposed PM
system over conventional modulation schemes in
terms of both higher throughput and lower BER.
In particular, our simulation results indicate that
the gain achieved by the proposed Q-dimensional
PM scheme spans between 10dB and 20dB compared
to the conventional modulation. It is also
demonstrated that the PM system attains between
54% and 87.5% improvements in terms of ergodic
capacity. Furthermore, we show that this technique
can be applied to MIMO systems in a synergistic
manner in order to achieve the target data rate
target for 5G wireless systems with much less
system resources (in terms of bandwidth and thenumber of antennas) compared to existing MIMO
techniques.
Xiao Lixia, Chen Da, Hemadeh Ibrahim, Xiao Pei, Jiang Tao (2020) Generalized Space Time Block Coded Spatial Modulation for Open-Loop Massive MIMO Downlink Communication Systems,IEEE Transactions on Communications Institute of Electrical and Electronics Engineers
In this paper, we propose a generalized space-time
block coded spatial modulation (GSTBC-SM) scheme for openloop massive multiple-input and multiple-output (MIMO) downlink communication systems. Specifically, we firstly partition the information bits into multiple groups with each group modulated by the spatial modulation (SM), where the SM symbols are invoked for orthogonal STBC (OSTBC) and quasi-orthogonal STBC (Q-OSTBC) structures. Then, message passing (MP) and block minimum mean square equalization (B-MMSE) detectors are designed for our GSTBC-SM systems, to achieve near-optimal performance with significantly reduced complexity in massive MIMO configurations. Finally, we derive the theoretical average bit error probability (ABEP) of the proposed scheme. The main contribution is that the propose scheme achieves high transmission
rate and diversity gain even with small number of radio
frequency (RF) chains at the transmitter. Simulation results verify the theoretical derivations and show that the proposed GSTBCSM scheme provides near 20 dB gain over the conventional GSTBC scheme under massive MIMO configurations.
Index Terms?Spatial Modulation (SM), Space Time Block
Coding (STBC), High throughput, Diversity gain.
Xiao Lixia, Chen Da, Hemadeh Ibrahim, Xiao Pei, Jiang Tao (2020) Graph Theory assisted Bit-to-Index-Combination Gray Coding for Generalized Index Modulation,IEEE Transactions on Wireless Communications Institute of Electrical and Electronics Engineers (IEEE)
Generalized index modulation (GIM) which implicitly
conveys information by the activated indices is a promising
technique for next-generation wireless networks. Due to the
prohibitive challenge of bit-to-index combination (IC) mapping
optimization, conventional GIM system obtains the bit-to-IC
mapping table randomly, which may suffer from some performance
loss. To circumvent this issue, we propose a low-complexity
graph theory assisted bit-to-IC gray coding for GIM systems by
minimizing the average hamming distance (HD) between any two
ICs having one different value. Specifically, we decompose and
transform the optimization problem into two subproblems using
the graph theory, i.e., 1) Select an IC set whose corresponding
graph has the minimum degree; 2) Design a bit-to-IC mapping
principle to minimize the weight of the selected graph. Low complexity
algorithms are developed to solve the subproblems
with a significant reduced complexity. Both simulation and
theoretical results are shown that the GIM systems with our
proposed mapping table are capable of providing significant
performance gains over the conventional counterparts without
the need for any additional feedback-link and without extra
computational complexity. It is also shown that the proposed
bit-to-IC mapping table is straightforward for any GIM systems
over generalized fading channels.
Xiao Lixia, Xiao Pei, Ruan Hang, Ishikawa Naoki, Lu Lei, Xiao Yue, Hanzo Lajos (2020) Differentially-encoded rectangular spatial modulation approaches the performance of its coherent counterpart,IEEE Transactions on Communications IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC
A simpli?ed rectangular differential spatial modulation (S-RDSM) scheme is conceived for massive multiple-input multiple-output (MIMO) systems dispensing with the channel state information (CSI). In the proposed S-RDSM scheme, the information bits are ?rst mapped to a conventional SM symbol and then rectangular differential encoding is invoked between a pair of SM symbols. Then a non-coherent detector relying on a forgetting factor is developed, which requires no CSI at the receiver. Explicitly, a low-complexity hard limited maximum likelihood (HL-ML) detector is conceived for our generalized SRDSMscheme,whichischaracterizedbyourtheoreticalanalysis. Furthermore, we derive the optimal forgetting factor in closed form, which is capable of signi?cantly reducing the complexity of the associated optimization. Finally, the upper bounds of the average bit error probability (ABEP) are derived using the moment generating function (MGF), and are validated by our simulation results. Both the theoretical and simulation results have shown that the proposed S-RDSM system outperforms the existing non-coherent schemes, despite operating at 10% of the benchmarker?s complexity, whilst approaching the performance of its coherent SM counterpart at a comparable complexity.