Biography

University roles and responsibilities

  • Research fellow: 5G-NR link level simulator

Research

Research interests

My publications

Publications

Trinh P, Pham T, Dang N, Nguyen H, Ng S, Pham A (2018) Design and Security Analysis of Quantum Key Distribution Protocol Over Free-Space Optics Using Dual-Threshold Direct-Detection Receiver,IEEE Access 6 pp. 4159-4175 Institute of Electrical and Electronics Engineers (IEEE)
This paper proposes a novel design and analyzes security performance of quantum key
distribution (QKD) protocol over free-space optics (FSO). Unlike conventional QKD protocols based on
physical characteristics of quantum mechanics, the proposed QKD protocol can be implemented on standard
FSO systems using subcarrier intensity modulation binary phase shift keying and direct detection with a
dual-threshold receiver. Under security constraints, the design criteria for FSO transmitter and receiver,
in particular, the modulation depth and the selection of dual-threshold detection, respectively, is analytically
investigated. For the security analysis, quantum bit error rate, ergodic secret-key rate, and final key-creation
rate are concisely derived in novel closed-form expressions in terms of finite power series, taking into account
the channel loss, atmospheric turbulence-induced fading, and receiver noises. Furthermore, Monte-Carlo
simulations are performed to verify analytical results and the feasibility of the proposed QKD protocol.
Nguyen H, Ng S, Liang W, Xiao P, Hanzo L (2018) A Network-Coding Aided Road-Map of Large-scale
Near-capacity Cooperative Communications
,
IEEE Access 6 (1) pp. 21592-21620 IEEE
In the paper, we present a road-map towards a Nearcapacity
Large-scale Multi-user Cooperative-communications
(NLMC) system, where all the evolution paths converge to the
construction of the NLMC system. More specifically, we will
summarise all relevant schemes appearing on the road-map
in the unified frame-work of forward error correction (FEC).
Various Network Coding (NC) design paradigms are highlighted
for illustrating how the NLMC systems might be designed for
meeting diverse design criteria in the context of cooperative
and cognitive communications, where the channel capacity of
the NLMC systems is used for comparing the different design
paradigms.
Izhar M, Babar Z, Nguyen H, Botsinis P, Alanis D, Chandra D, Ng S, Hanzo L (2018) Quantum Turbo Decoding for Quantum
Channels Exhibiting Memory
,
IEEE Access 6 (1) pp. 12369-12381 IEEE
Inspired by the success of classical turbo codes, quantum turbo codes (QTCs) have also
been conceived for near-hashing-bound transmission of quantum information over memoryless quantum
channels. However, in real physical situations, the memoryless channel assumption may not be well justified
since the channel often exhibits memory of previous error events. Here, we investigate the performance of
QTCs over depolarizing channels exhibiting memory and we show that they suffer from a performance
degradation at low depolarizing probability values. In order to circumvent the performance degradation issue,
we conceive a new coding scheme termed as quantum turbo coding scheme exploiting error-correlation
(QTC-EEC) that is capable of utilizing the error-correlation while performing the iterative decoding at the
receiver. The proposed QTC-EEC can achieve convergence threshold at a higher depolarizing probability
for channels with a higher value of correlation parameter and achieve performance near to the capacity.
Finally, we propose a joint decoding and estimation scheme for our QTC-EEC relying on correlation
estimation (QTC-EEC-E) designed for more realistic quantum systems with unknown correlation parameter.
Simulation results reveal that the proposed QTC-EEC-E can achieve the same performance as that of the
ideal system of known correlation parameter and hence, demonstrate the accurate estimation of the proposed
QTC-EEC-E.
Alanis Dimitrios, Botsinis Panagiotis, Babar Zunaira, Nguyen Hung Viet, Chandra Daryus, Ng Soon Xin, Hanzo Lajos (2018) A Quantum-Search-Aided Dynamic Programming Framework for Pareto Optimal Routing in Wireless Multihop Networks,IEEE Transactions on Communications 66 (8) pp. 3485-3500 Institute of Electrical and Electronics Engineers (IEEE)
Wireless Multihop Networks (WMHNs) have to strike a trade-off among diverse and often conflicting Qualityof-Service (QoS) requirements. The resultant solutions may be included by the Pareto Front under the concept of Pareto Optimality. However, the problem of finding all the Pareto-optimal routes in WMHNs is classified as NP-hard, since the number of legitimate routes increases exponentially, as the nodes proliferate. Quantum Computing offers an attractive framework of rendering the Pareto-optimal routing problem tractable. In this context, a pair of quantum-assisted algorithms have been proposed, namely the Non-Dominated Quantum Optimization (NDQO) and the Non-Dominated Quantum Iterative Optimization (NDQIO). However, their complexity is proportional to ?N, where N corresponds to the total number of legitimate routes, thus still failing to find the solutions in ?polynomial time?. As a remedy, we devise a dynamic programming framework and propose the so-called Evolutionary Quantum Pareto Optimization (EQPO) algorithm. We analytically characterize the complexity imposed by the EQPO algorithm and demonstrate that it succeeds in solving the Pareto-optimal routing problem in polynomial time. Finally, we demonstrate by simulations that the EQPO algorithm achieves a complexity reduction, which is at least an order of magnitude, when compared to its predecessors, albeit at the cost of a modest heuristic accuracy reduction.
Gyongyosi Laszlo, Imre Sandor, Nguyen Hung Viet (2018) A Survey on Quantum Channel Capacities,IEEE Communications Surveys & Tutorials 20 (2) pp. 1149-1205 Institute of Electrical and Electronics Engineers (IEEE)
Quantum information processing exploits the quantum nature of information. It offers fundamentally new solutions in the field of computer science and extends the possibilities to a level that cannot be imagined in classical communication systems. For quantum communication channels, many new capacity definitions were developed in comparison to classical counterparts. A quantum channel can be used to realize classical information transmission or to deliver quantum information, such as quantum entanglement. Here we review the properties of the quantum communication channel, the various capacity measures and the fundamental differences between the classical and quantum channels.
Chandra D, Babar Z, Nguyen Hung, Alanis D, Botsinis P, Ng S, Hanzo L (2017) Quantum Topological Error Correction Codes: The Classical-to-Quantum Isomorphism Perspective,IEEE Access 6 (1) pp. 13729-13757 IEEE
We conceive and investigate the family of classical topological error correction codes (TECCs),
which have the bits of a codeword arranged in a lattice structure. We then present the classical-toquantum
isomorphism to pave the way for constructing their quantum dual pairs, namely, the quantum
TECCs (QTECCs). Finally, we characterize the performance of QTECCs in the face of the quantum
depolarizing channel in terms of both the quantum-bit error rate (QBER) and fidelity. Specifically, from
our simulation results, the threshold probability of the QBER curves for the color codes, rotated-surface
codes, surface codes, and toric codes are given by 1.8 × 10?2
, 1.3 × 10?2
, 6.3 × 10?2
, and 6.8 × 10?2
,
respectively. Furthermore, we also demonstrate that we can achieve the benefit of fidelity improvement at the
minimum fidelity of 0.94, 0.97, and 0.99 by employing the 1/7-rate color code, the 1/9-rate rotated-surface
code, and 1/13-rate surface code, respectively.
Alanis Dimitrios, Botsinis Panagiotis, Babar Zunaira, Nguyen Hung, Chandra Daryus, Ng Soon Xin, Hanzo Lajos (2018) Quantum-aided Multi-Objective Routing Optimization Using Back-Tracing-Aided Dynamic Programming,IEEE Transactions on Vehicular Technology 67 (8) pp. 7856-7860 Institute of Electrical and Electronics Engineers (IEEE)
Pareto optimality is capable of striking the optimal trade-off amongst the diverse conflicting QoS requirements of routing in wireless multihop networks. However, this comes at the cost of increased complexity owing to searching through the extended multi-objective search-space. We will demonstrate that the powerful quantum-assisted dynamic programming optimization framework is capable of circumventing this problem. In this context, the so-called Evolutionary Quantum Pareto Optimization~(EQPO) algorithm has been proposed, which is capable of identifying most of the optimal routes at a near-polynomial complexity versus the number of nodes. As a benefit, we improve both the the EQPO algorithm by introducing a back-tracing process. We also demonstrate that the improved algorithm, namely the Back-Tracing-Aided EQPO (BTA-EQPO) algorithm, imposes a negligible complexity overhead, while substantially improving our performance metrics, namely the relative frequency of finding all Pareto-optimal solutions and the probability that the Pareto-optimal solutions are indeed part of the optimal Pareto front.
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 Access 6 pp. 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.
Babar Zunaira, Chandra Daryus, Nguyen Hung, Botsinis Panagiotis, Alanis Dimitrios, Ng Soon Xin, Hanzo Lajos (2018) Duality of Quantum and Classical Error Correction Codes: Design Principles and Examples,IEEE Communications Surveys and Tutorials IEEE
Quantum Error Correction Codes (QECCs) can
be constructed from the known classical coding paradigm by
exploiting the inherent isomorphism between the classical and
quantum regimes, while also addressing the challenges imposed
by the strange laws of quantum physics. In this spirit, this
paper provides deep insights into the duality of quantum and
classical coding theory, hence aiming for bridging the gap between
them. Explicitly, we survey the rich history of both classical
as well as quantum codes. We then provide a comprehensive
slow-paced tutorial for constructing stabilizer-based QECCs from
arbitrary binary as well as quaternary codes, as exemplified by
the dual-containing and non-dual-containing Calderbank-Shor-
Steane (CSS) codes, non-CSS codes and entanglement-assisted
codes. Finally, we apply our discussions to two popular code
families, namely to the family of Bose-Chaudhuri-Hocquenghem
(BCH) as well as of convolutional codes and provide detailed
design examples for both their classical as well as their quantum
versions.
Nguyen H. Le, Lanskii Grigory V., Aeppli G. Aeppli, Murdin B.N. Murdin (2019) Giant non-linear susceptibility of hydrogenic donors in silicon and germanium,Light: Science & Applications 8 64 pp. 1-7 Springer Nature
Implicit summation is a technique for conversion of sums over intermediate states in multiphoton
absorption and the high-order susceptibility in hydrogen into simple integrals. Here we derive the
equivalent technique for hydrogenic impurities in multi-valley semiconductors. While the absorption
has useful applications it is primarily a loss process, conversely the non-linear susceptibility is a
crucial parameter for active photonic devices. For Si:P we predict the hyperpolarizability ranges
from X(3)Dn3D = 2:9 to 580x10-38m5V2 depending on the frequency even while avoiding resonance.
Using samples of reasonable density n3D and thickness L to produce third harmonic generation at
9 THz, a frequency that is difficult to produce with existing solid state sources, we predict that X(3)
should exceed that of bulk InSb and X(3)L should exceed that of graphene and resonantly enhanced
quantum wells.