TY - JOUR
T1 - Optimization for Signal Transmission and Reception in a Macrocell of Heterogeneous Uplinks and Downlinks
AU - Yu, Hongwen
AU - Tuan, Hoang Duong
AU - Duong, Trung Q.
AU - Poor, H. Vincent
AU - Fang, Yong
N1 - Funding Information:
This work was supported in part by the National Natural Science Foundation of China (NSFC) under Grant 61901254 and Grant 61673253, in part by the Institute for Computational Science and Technology, Hochiminh City, Vietnam, in part by the Australian Research Councils Discovery Projects under Grant DP190102501, in part by the U.K. Royal Academy of Engineering under Grants RF1415\14\22 and RCSRF2021\11\41, and in part by the U.S. National Science Foundation under Grant CCF-0939370 and Grant CCF-1908308.
Funding Information:
Manuscript received February 2, 2020; revised June 8, 2020; accepted July 30, 2020. Date of publication August 7, 2020; date of current version November 18, 2020. This work was supported in part by the National Natural Science Foundation of China (NSFC) under Grant 61901254 and Grant 61673253, in part by the Institute for Computational Science and Technology, Hochiminh City, Vietnam, in part by the Australian Research Councils Discovery Projects under Grant DP190102501, in part by the U.K. Royal Academy of Engineering under Grants RF1415\14\22 and RCSRF2021\11\41, and in part by the U.S. National Science Foundation under Grant CCF-0939370 and Grant CCF-1908308. The associate editor coordinating the review of this article and approving it for publication was F. Verde. (Corresponding author: Trung Q. Duong.) Hongwen Yu is with the School of Communication and Information Engineering, Shanghai University, Shanghai 200444, China, and also with the School of Electrical and Data Engineering, University of Technology Sydney at Broadway, Ultimo, NSW 2007, Australia (e-mail: hongwen.yu@student.uts.edu.au).
Publisher Copyright:
© 1972-2012 IEEE.
PY - 2020/11
Y1 - 2020/11
N2 - Internet-of-things (IoT) applications continue to drive advancements in serving as many heterogeneous low-latency downlinks and uplinks as possible within a constrained communication bandwidth. Full-duplexing (FD) transceivers have been introduced to implement simultaneous signal transmission and reception (STR) over the entire available frequency band. However, both inter-link interference and FD loop-interference are hardly suppressed to a necessary level for the effectiveness of FD-based STR even for microcells. This paper proposes an alternative STR technique per one time-slot for macrocells, where a fraction of a time-slot is used for downlinks and the remaining complementary fraction of the time-slot is used for uplinks. Thus, STR over the entire available bandwidth can be implemented in a way with no loop interference. Furthermore, another approach of using a fraction of the available bandwidth for downlinks and the remaining complementary fraction of the bandwidth for uplinks over the whole time-slot is also proposed. The problem of both downlink and uplink beamforming to maximize the energy efficiency of such heterogeneous networks subject to the quality-of-service in terms of downlink and uplink throughput is examined for all three possible STRs. Numerical results demonstrate the advantages of the time-fraction-wise STR and bandwidth-fraction-wise STR over the FD-based STR, where the time-fraction-wise STR is not only the best in serving the same numbers of downlinks and uplinks but also is capable of serving many more downlinks and uplinks with a higher energy efficiency.
AB - Internet-of-things (IoT) applications continue to drive advancements in serving as many heterogeneous low-latency downlinks and uplinks as possible within a constrained communication bandwidth. Full-duplexing (FD) transceivers have been introduced to implement simultaneous signal transmission and reception (STR) over the entire available frequency band. However, both inter-link interference and FD loop-interference are hardly suppressed to a necessary level for the effectiveness of FD-based STR even for microcells. This paper proposes an alternative STR technique per one time-slot for macrocells, where a fraction of a time-slot is used for downlinks and the remaining complementary fraction of the time-slot is used for uplinks. Thus, STR over the entire available bandwidth can be implemented in a way with no loop interference. Furthermore, another approach of using a fraction of the available bandwidth for downlinks and the remaining complementary fraction of the bandwidth for uplinks over the whole time-slot is also proposed. The problem of both downlink and uplink beamforming to maximize the energy efficiency of such heterogeneous networks subject to the quality-of-service in terms of downlink and uplink throughput is examined for all three possible STRs. Numerical results demonstrate the advantages of the time-fraction-wise STR and bandwidth-fraction-wise STR over the FD-based STR, where the time-fraction-wise STR is not only the best in serving the same numbers of downlinks and uplinks but also is capable of serving many more downlinks and uplinks with a higher energy efficiency.
KW - Heterogeneous networks
KW - downlink and uplink beamforming
KW - energy efficiency
KW - fractional bandwidth allocation
KW - fractional time-slot allocation
KW - nonconvex optimization
KW - signal transmission and reception
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U2 - 10.1109/TCOMM.2020.3014945
DO - 10.1109/TCOMM.2020.3014945
M3 - Article
AN - SCOPUS:85096685729
SN - 1558-0857
VL - 68
SP - 7054
EP - 7067
JO - IEEE Transactions on Communications
JF - IEEE Transactions on Communications
IS - 11
M1 - 9162046
ER -