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Chu, Thi My Chinh
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Publications (10 of 44) Show all publications
Chu, T. M. & Zepernick, H.-J. (2018). Downlink outage analysis for cognitive cooperative radio networks employing non-orthogonal multiple access. In: 2018 IEEE 7th International Conference on Communications and Electronics, ICCE 2018: . Paper presented at 7th IEEE International Conference on Communications and Electronics, ICCE 2018,Saigon Morin HotelHue; Viet Nam, 18 July 2018 through 20 July 2018 (pp. 27-32). Institute of Electrical and Electronics Engineers Inc.
Open this publication in new window or tab >>Downlink outage analysis for cognitive cooperative radio networks employing non-orthogonal multiple access
2018 (English)In: 2018 IEEE 7th International Conference on Communications and Electronics, ICCE 2018, Institute of Electrical and Electronics Engineers Inc. , 2018, p. 27-32Conference paper, Published paper (Refereed)
Abstract [en]

In this paper, we employ power-domain non-orthogonal multiple access (NOMA) to simultaneously transmit signals to both a primary user (PU) and a secondary user (SU) of a cognitive cooperative radio network (CCRN). Higher priority is given to the PU over the SU by keeping the power allocation coefficients at the base station (BS) and relay (R) above a certain threshold. In this way, similar as the interference power limit imposed by the PU in a conventional underlay CCRN, the power allocation coefficients at the BS and R of the CCRN can be controlled to maintain a given outage performance. Analytical expressions of the cumulative distribution function of the end-to-end signal-to-interference-plus-noise ratios at the PU and SU are derived and then used to assess the outage probabilities of both users. Numerical results are presented to study the impact of system parameters on outage performance of the CCRN with power-domain NOMA. In addition, it is illustrated that increased downlink performance can be obtained by combining power-domain NOMA with CCRNs. © 2018 IEEE.

Place, publisher, year, edition, pages
Institute of Electrical and Electronics Engineers Inc., 2018
Keywords
Cognitive radio, Distribution functions, Mobile telecommunication systems, Probability distributions, Signal to noise ratio, Analytical expressions, Cognitive cooperative radio networks, Cumulative distribution function, Downlink performance, Interference power, Non orthogonal multiple accesses (NOMA), Non-orthogonal multiple access, Signal to interference plus noise ratio, Outages
National Category
Telecommunications
Identifiers
urn:nbn:se:bth-17426 (URN)10.1109/CCE.2018.8465755 (DOI)2-s2.0-85057577602 (Scopus ID)9781538636787 (ISBN)
Conference
7th IEEE International Conference on Communications and Electronics, ICCE 2018,Saigon Morin HotelHue; Viet Nam, 18 July 2018 through 20 July 2018
Available from: 2018-12-13 Created: 2018-12-13 Last updated: 2018-12-13Bibliographically approved
Chu, T. M. & Zepernick, H.-J. (2018). Non-orthogonal multiple access for DF cognitive cooperative radio networks. In: IEEE International Conference on Communications Workshops: . Paper presented at IEEE International Conference on Communications Workshops, ICC Workshops 2018; Kansas City (pp. 1-6). Institute of Electrical and Electronics Engineers Inc.
Open this publication in new window or tab >>Non-orthogonal multiple access for DF cognitive cooperative radio networks
2018 (English)In: IEEE International Conference on Communications Workshops, Institute of Electrical and Electronics Engineers Inc. , 2018, p. 1-6Conference paper, Published paper (Refereed)
Abstract [en]

In this paper, we study a power domain non-orthogonal multiple access (NOMA) scheme for cognitive cooperative radio networks (CCRNs). In the proposed scheme, a secondary transmitter communicates with two secondary users (SUs) by allocating transmit powers inversely proportional to the channel power gains on the links to the respective SUs. A decode-and-forward (DF) secondary relay is deployed which decodes the superimposed signals associated with the two SUs. Then, power domain NOMA is used to forward the signals from the relay to the two SUs based on the channel power gains on the corresponding two links. Mathematical expressions for the outage probability and ergodic capacity of each SU and the overall power domain NOMA CCRN are derived. Numerical results are provided to reveal the impact of the power allocation coefficients at the secondary transmitter and secondary relay, the interference power threshold at the primary receiver, and the normalized distances of the SUs on the outage probability and ergodic capacity of each SU and the whole NOMA system. © 2018 IEEE.

Place, publisher, year, edition, pages
Institute of Electrical and Electronics Engineers Inc., 2018
Series
IEEE International Conference on Communications Workshops, ISSN 2164-7038
National Category
Telecommunications
Identifiers
urn:nbn:se:bth-16905 (URN)10.1109/ICCW.2018.8403614 (DOI)000445022200128 ()2-s2.0-85050303770 (Scopus ID)9781538643280 (ISBN)
Conference
IEEE International Conference on Communications Workshops, ICC Workshops 2018; Kansas City
Available from: 2018-08-20 Created: 2018-08-20 Last updated: 2018-10-18Bibliographically approved
Chu, T. M. & Zepernick, H.-J. (2018). Optimal Power Allocation for Hybrid Cognitive Cooperative Radio Networks with Imperfect Spectrum Sensing. IEEE Access, 6, 10365-10380
Open this publication in new window or tab >>Optimal Power Allocation for Hybrid Cognitive Cooperative Radio Networks with Imperfect Spectrum Sensing
2018 (English)In: IEEE Access, E-ISSN 2169-3536, Vol. 6, p. 10365-10380Article in journal (Refereed) Published
Abstract [en]

In this paper, two optimal power allocation strategies for hybrid interweave-underlay cognitive cooperative radio networks (CCRNs) are proposed to maximize channel capacity and minimize outage probability. The proposed power allocation strategies are derived for the case of Rayleigh fading taking into account the impact of imperfect spectrum sensing on the performance of the hybrid CCRN. Based on the optimal power allocation strategies, the transmit powers of the secondary transmitter and secondary relay are adapted according to the fading conditions, the interference power constraint imposed by the primary network (PN), the interference from the PN to the hybrid CCRN, and the total transmit power limit of the hybrid CCRN. Numerical results are provided to illustrate the effect of the interference power constraint of the PN, arrival rate of the PN, imperfect spectrum sensing, and the transmit power constraint of the hybrid CCRN on channel capacity and outage probability. Finally, comparisons of the channel capacity and outage probability of underlay, overlay, and hybrid interweaveunderlay CCRNs are presented to show the advantages of the hybrid spectrum access. OAPA

Place, publisher, year, edition, pages
Institute of Electrical and Electronics Engineers Inc., 2018
Keywords
amplify-and-forward relaying, Channel capacity, Cognitive radio, hybrid interweave-underlay scheme, Hybrid power systems, imperfect spectrum sensing, Interference, outage probability, power allocation, Power system reliability, Probability, Resource management, Sensors, Cognitive systems, Fading (radio), Rayleigh fading, Wave interference, Power allocations, Outages
National Category
Telecommunications
Identifiers
urn:nbn:se:bth-15892 (URN)10.1109/ACCESS.2018.2792063 (DOI)000428148400001 ()2-s2.0-85041174409 (Scopus ID)
Available from: 2018-02-15 Created: 2018-02-15 Last updated: 2018-04-12Bibliographically approved
Chu, T. M. & Zepernick, H.-J. (2018). Performance of a Non-orthogonal Multiple Access System with Full-Duplex Relaying. IEEE Communications Letters, 22(10), 2084-2087
Open this publication in new window or tab >>Performance of a Non-orthogonal Multiple Access System with Full-Duplex Relaying
2018 (English)In: IEEE Communications Letters, ISSN 1089-7798, E-ISSN 1558-2558, Vol. 22, no 10, p. 2084-2087Article in journal (Refereed) Published
Abstract [en]

In this paper, we study a power-domain nonorthogonal multiple access (NOMA) system in which a base station (BS) superimposes the transmit signals to the users. To enhance spectral efficiency and link reliability for the far-distance user, a full-duplex (FD) relay assists the BS while the neardistance user is reached over the direct link. For this setting, we analyze outage probability and sum rate of the NOMA system over Nakagami-m fading with integer fading severity parameter m. Numerical results are provided for outage probability and sum rate to show the effect of system parameters on the performance of the FD NOMA system over Nakagami-m fading. IEEE

Place, publisher, year, edition, pages
Institute of Electrical and Electronics Engineers Inc., 2018
Keywords
full-duplex, NOMA, outage, sum rate, Finite difference method, Full-duplex relaying, Non orthogonal multiple accesses (NOMA), Non-orthogonal multiple access, Outage probability, Spectral efficiencies, Sum-rate, Outages
National Category
Telecommunications
Identifiers
urn:nbn:se:bth-16887 (URN)10.1109/LCOMM.2018.2852308 (DOI)000447079300030 ()2-s2.0-85049336586 (Scopus ID)
Available from: 2018-08-20 Created: 2018-08-20 Last updated: 2018-10-30Bibliographically approved
Chu, T. M. & Zepernick, H.-J. (2018). Performance Optimization for Hybrid Two-Way Cognitive Cooperative Radio Networks with Imperfect Spectrum Sensing. IEEE Access, 6, 70582-70596
Open this publication in new window or tab >>Performance Optimization for Hybrid Two-Way Cognitive Cooperative Radio Networks with Imperfect Spectrum Sensing
2018 (English)In: IEEE Access, E-ISSN 2169-3536, Vol. 6, p. 70582-70596Article in journal (Refereed) Published
Abstract [en]

In this paper, we consider a two-way cognitive cooperative radio network (TW-CCRN) with hybrid interweaveunderlay spectrum access in the presence of imperfect spectrum sensing. Power allocation strategies are proposed that maximize the sum-rate and minimize the outage probability of the hybrid TW-CCRN. Specifically, based on the state of the primary network (PN), fading conditions, and system parameters, suitable power allocation strategies subject to the interference power constraint of the PN are derived for each transmission scenario of the hybrid TW-CCRN. Given the proposed power allocation strategies, we analyze the sum-rate and outage probability of the hybrid TW-CCRN over Rayleigh fading taking imperfect spectrum sensing into account. Numerical results are presented to illustrate the effect of the arrival rate, interference power threshold, transmit power of the PN, imperfect spectrum sensing, and maximum total transmit power on the sum-rate and outage probability of the hybrid TW-CCRN. OAPA

Place, publisher, year, edition, pages
Institute of Electrical and Electronics Engineers Inc., 2018
Keywords
Cognitive cooperative radio network, hybrid interweave-underlay spectrum access, Hybrid power systems, Interference, outage probability, power allocation, Power system reliability, Probability, Relays, Resource management, Sensors, sum-rate, two-way communications, Cognitive radio, Cognitive systems, Cooperative communication, Rayleigh fading, Spectroscopy, Wave interference, Cognitive cooperative radio networks, Power allocations, Spectrum access, Two way communications, Outages
National Category
Telecommunications
Identifiers
urn:nbn:se:bth-17349 (URN)10.1109/ACCESS.2018.2879901 (DOI)000453265500001 ()2-s2.0-85056331705 (Scopus ID)
Available from: 2018-11-29 Created: 2018-11-29 Last updated: 2019-01-09Bibliographically approved
Chu, T. M. & Zepernick, H.-J. (2018). Symbol error rate and achievable rate of cognitive cooperative radio networks utilizing non-orthogonal multiple access. In: 2018 IEEE 7th International Conference on Communications and Electronics, ICCE 2018: . Paper presented at 7th IEEE International Conference on Communications and Electronics, ICCE 2018, Saigon Morin HotelHue; Viet Nam, 18 July 2018 through 20 July 2018 (pp. 33-38). Institute of Electrical and Electronics Engineers Inc., Code 141951
Open this publication in new window or tab >>Symbol error rate and achievable rate of cognitive cooperative radio networks utilizing non-orthogonal multiple access
2018 (English)In: 2018 IEEE 7th International Conference on Communications and Electronics, ICCE 2018, Institute of Electrical and Electronics Engineers Inc. , 2018, Vol. Code 141951, p. 33-38Conference paper, Published paper (Refereed)
Abstract [en]

In this paper, we study the employment of power-domain non-orthogonal multiple access (NOMA) concepts for a cooperative cognitive relay network (CCRN) downlink system in order to allow a base station (BS) to simultaneously transmit signals to a primary user (PU) and a secondary user (SU). As such, the considered system falls into the field of cognitive radio inspired power-domain NOMA. In this scheme, the interference power constraint of the PU imposed to SUs in conventional underlay CCRNs is replaced by controlling the power allocation coefficients at the BS and relay. Specifically, expressions for the symbol error rates at the PU and SU for different modulation schemes as well as expressions for the achievable rates are derived. On this basis, the effect of system parameters such as total transmit power and power allocation coefficients on the performance of the CCRN with power-domain NOMA is numerically studied. These numerical results provide insights into selecting favorable operation modes of the CCRN employing power-domain NOMA. © 2018 IEEE.

Place, publisher, year, edition, pages
Institute of Electrical and Electronics Engineers Inc., 2018
Keywords
Electronics engineering, Electronics industry, Cognitive cooperative radio networks, Cognitive relay networks, Interference power constraints, Modulation schemes, Non orthogonal multiple accesses (NOMA), Non-orthogonal multiple access, Symbol error rate (SER), Total transmit power, Cognitive radio
National Category
Telecommunications
Identifiers
urn:nbn:se:bth-17427 (URN)10.1109/CCE.2018.8465739 (DOI)2-s2.0-85057619071 (Scopus ID)9781538636787 (ISBN)
Conference
7th IEEE International Conference on Communications and Electronics, ICCE 2018, Saigon Morin HotelHue; Viet Nam, 18 July 2018 through 20 July 2018
Available from: 2018-12-13 Created: 2018-12-13 Last updated: 2018-12-13Bibliographically approved
Chu, T. M. & Zepernick, H.-J. (2017). Capacity Analysis of Two-Tier Networks with MIMO Cognitive Small Cells in Nagakami-m Fading. In: 2017 IEEE 13TH INTERNATIONAL CONFERENCE ON WIRELESS AND MOBILE COMPUTING, NETWORKING AND COMMUNICATIONS (WIMOB): . Paper presented at 13th IEEE International Conference on Wireless and Mobile Computing, Networking and Communications (WiMob), Rome (pp. 457-463). IEEE
Open this publication in new window or tab >>Capacity Analysis of Two-Tier Networks with MIMO Cognitive Small Cells in Nagakami-m Fading
2017 (English)In: 2017 IEEE 13TH INTERNATIONAL CONFERENCE ON WIRELESS AND MOBILE COMPUTING, NETWORKING AND COMMUNICATIONS (WIMOB), IEEE , 2017, p. 457-463Conference paper, Published paper (Refereed)
Abstract [en]

In this paper, we consider a two-tier cellular network consisting of a primary macro cell base station (PMBS) which is overlaid by cognitive small cell base stations (CSBSs) to achieve efficient spectrum utilization. The deployment of two-tier cellular networks can provide higher capacity for the system but also causes cross-tier, intra-tier, and inter-tier interference within the cellular networks. Thus, we employ transmit and receive beamforming in the considered two-tier cellular network to mitigate interference. We first design the receive beamforming vector for a primary user (PU) such that it cancels all inter-tier interference from other PUs. Then, the transmit beamforming vectors at the secondary users (SUs) are designed to null out the cross-tier interference to the PUs. Further, the receive beamforming vectors at the SUs are designed to mitigate the crosstier interference from the PUs to the SUs. Finally, the transmit beamforming vector at the PMBS is designed to maximize the signal-to-interference-plus-noise ratio at the PUs. To quantify the performance of the system, we derive an expression for the channel capacity in the downlink from the CSBSs to the SUs. Numerical results are provided to reveal the effect of network parameters such as intra-tier interference distances, fading conditions, and number of antennas on the channel capacity of the SUs.

Place, publisher, year, edition, pages
IEEE, 2017
Series
IEEE International Conference on Wireless and Mobile Computing Networking and Communications-WiMOB, ISSN 2160-4886
National Category
Telecommunications
Identifiers
urn:nbn:se:bth-15882 (URN)000419818000063 ()978-1-5386-3839-2 (ISBN)
Conference
13th IEEE International Conference on Wireless and Mobile Computing, Networking and Communications (WiMob), Rome
Available from: 2018-02-09 Created: 2018-02-09 Last updated: 2018-02-22Bibliographically approved
Zepernick, H.-J. & Chu, T. M. (2017). Descriptive Statistical Analysis of Subjective Experiments in Mobile Imaging. In: Wysocki, TA Wysocki, BJ (Ed.), 11th International Conference on Signal Processing and Communication Systems, ICSPCS 2017: . Paper presented at 11th International Conference on Signal Processing and Communication Systems (ICSPCS), Surfers Paradise, Australia. IEEE
Open this publication in new window or tab >>Descriptive Statistical Analysis of Subjective Experiments in Mobile Imaging
2017 (English)In: 11th International Conference on Signal Processing and Communication Systems, ICSPCS 2017 / [ed] Wysocki, TA Wysocki, BJ, IEEE , 2017Conference paper, Published paper (Refereed)
Abstract [en]

In this paper, we provide a descriptive statistical analysis of subjective experiments in mobile imaging. Most of the statistical analyses of such experiments use condensed statistics such as mean opinion scores along with standard deviations. These statistics give only limited insights on the underlaying distribution of a data set. On the other hand, higher order statistics such as skewness and kurtosis provide additional information about a distribution but their qualitative interpretation is complicated. In order to alleviate these shortcomings, we advocate the use of box plots to efficiently visualize and compare distributions between different sets of image quality scores. Specifically, box plots serve the purposes of accounting for the diversity in image quality scores as well as supporting an intuitive qualitative interpretation of the results. It is shown by analysing two subjective experiments of the wireless imaging quality database that notched box plots are beneficial in quickly assessing the statistical significance among differences in such experiments. Further, box plots are used to identify those test material that received a wide diversity in image quality scores including outliers.

Place, publisher, year, edition, pages
IEEE, 2017
National Category
Telecommunications
Identifiers
urn:nbn:se:bth-15991 (URN)000425961900044 ()978-1-5386-2887-4 (ISBN)
Conference
11th International Conference on Signal Processing and Communication Systems (ICSPCS), Surfers Paradise, Australia
Available from: 2018-03-23 Created: 2018-03-23 Last updated: 2018-07-10Bibliographically approved
Chu, T. M., Zepernick, H.-J. & Phan, H. (2017). MAC Protocol for Opportunistic Spectrum Access in Multi-Channel Cognitive Relay Networks. In: IEEE Vehicular Technology Conference: . Paper presented at 85th IEEE Vehicular Technology Conference, Sydney. Institute of Electrical and Electronics Engineers Inc.
Open this publication in new window or tab >>MAC Protocol for Opportunistic Spectrum Access in Multi-Channel Cognitive Relay Networks
2017 (English)In: IEEE Vehicular Technology Conference, Institute of Electrical and Electronics Engineers Inc. , 2017Conference paper, Published paper (Refereed)
Abstract [en]

In this paper, we propose a medium access control (MAC) protocol for multi-channel cognitive cooperative radio networks (CCRNs). In this protocol, each secondary user (SU) senses for spectrum opportunities within M licensed bands of the primary users (PUs). To enhance the accuracy of spectrum sensing, we employ cooperative sequential spectrum sensing where SUs mutually exchange their sensing results. Moreover, the information obtained from cooperative spectrum sensing at the physical layer is integrated into the channel negotiation process at the MAC layer to alleviate the hidden terminal problem. Finally, the performance of the proposed MAC protocol in terms of aggregate throughput of the CCRNs is analyzed. Numerical results are provided to assess the impact of channel utilization by PUs, number of contenting CCRNs, number of licensed bands, and false alarm probability of SUs on the aggregate throughput. © 2017 IEEE.

Place, publisher, year, edition, pages
Institute of Electrical and Electronics Engineers Inc., 2017
Series
IEEE Vehicular Technology Conference Proceedings
Keywords
Access control, Aggregates, Cognitive radio, Internet protocols, Network layers, Aggregate throughput, Co-operative spectrum sensing, Cognitive relay networks, False alarm probability, Hidden terminal problems, Medium access control protocols, Negotiation process, Opportunistic spectrum access, Medium access control
National Category
Telecommunications
Identifiers
urn:nbn:se:bth-15852 (URN)10.1109/VTCSpring.2017.8108220 (DOI)000426875800040 ()2-s2.0-85040548983 (Scopus ID)9781509059324 (ISBN)
Conference
85th IEEE Vehicular Technology Conference, Sydney
Available from: 2018-02-02 Created: 2018-02-02 Last updated: 2018-04-19Bibliographically approved
Chu, T. M. & Zepernick, H.-J. (2017). On Capacity of Full-Duplex Cognitive Cooperative Radio Networks with Optimal Power Allocation. In: 2017 IEEE WIRELESS COMMUNICATIONS AND NETWORKING CONFERENCE (WCNC): . Paper presented at IEEE Wireless Communications and Networking Conference (WCNC), MAR 19-22, 2017, San Francisco, CA. IEEE
Open this publication in new window or tab >>On Capacity of Full-Duplex Cognitive Cooperative Radio Networks with Optimal Power Allocation
2017 (English)In: 2017 IEEE WIRELESS COMMUNICATIONS AND NETWORKING CONFERENCE (WCNC), IEEE , 2017Conference paper, Published paper (Refereed)
Abstract [en]

In this paper, we examine a full-duplex transmission scheme for cognitive cooperative radio networks (CCRNs) to improve capacity. In this network, the secondary transmitter and secondary relay are allowed to utilize the licensed spectrum of the primary user by using underlay spectrum access. We assume that the CCRN is subject to the interference power constraint of the primary receiver and maximum transmit power limit of the secondary transmitter and secondary relay. Under these constraints, we propose an optimal power allocation policy for the secondary transmitter and the secondary relay based on average channel state information (CSI) to optimize capacity. Then, we derive an expression for the corresponding achievable capacity of the secondary network over Nakagami-m fading. Numerical results are provided for several scenarios to study the achievable capacity that can be offered by this full-duplex underlay CCRN using the proposed optimal power allocation scheme.

Place, publisher, year, edition, pages
IEEE, 2017
Series
IEEE Wireless Communications and Networking Conference, ISSN 1525-3511
National Category
Telecommunications Communication Systems
Identifiers
urn:nbn:se:bth-14844 (URN)000403137600215 ()978-1-5090-4183-1 (ISBN)
Conference
IEEE Wireless Communications and Networking Conference (WCNC), MAR 19-22, 2017, San Francisco, CA
Available from: 2017-07-03 Created: 2017-07-03 Last updated: 2017-07-04Bibliographically approved
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