The rapid development and continuous updating of the mega satellite constellation(MSC)have brought new visions for the future 6G coverage extension, where the global seamless signal coverage can realize ubiquitous ser...The rapid development and continuous updating of the mega satellite constellation(MSC)have brought new visions for the future 6G coverage extension, where the global seamless signal coverage can realize ubiquitous services for user terminals. However, global traffic demands present nonuniform characteristics. Therefore, how to ensure the on-demand service coverage for the specific traffic demand, i.e., the ratio of traffic density to service requirement per unit area, is the core issue of 6G wireless coverage extension exploiting the MSC. To this regard, this paper first discusses the open challenges to reveal the future direction of 6G wireless coverage extension from the perspective of key factors affecting service coverage performance, i.e., the network access capacity, space segment capacity and their matchingrelationship. Furthermore, we elaborate on the key factors affecting effective matchings of the aforementioned aspects, thereby improving service coverage capability.展开更多
Millimeter-wave(mm Wave) communications will be used in fifth-generation(5G) mobile communication systems, but they experience severe path loss and have high sensitivity to physical objects, leading to smaller cell ra...Millimeter-wave(mm Wave) communications will be used in fifth-generation(5G) mobile communication systems, but they experience severe path loss and have high sensitivity to physical objects, leading to smaller cell radii and complicated network architectures. A coverage extension scheme using large-scale antenna arrays(LSAAs) has been suggested and theoretically proven to be cost-efficient in combination with ultradense small cell networks. To analyze and optimize the LSAA-based network deployments, a comprehensive survey of recent advances in statistical mmWave channel modeling is first presented in terms of channel parameter estimation, large-scale path loss models, and small-scale cluster models. Next, the measurement and modeling results at two 5G candidate mmWave bands(e.g., 28 GHz and 39 GHz) are reviewed and compared in several outdoor scenarios of interest, where the propagation characteristics make crucial contributions to wireless network designs. Finally, the coverage behaviors of systems employing a large number of antenna arrays are discussed, as well as some implications on future mmWave cellular network designs.展开更多
This paper shows the procedure to obtain a continuous coverage map based on a collection of power meas- urements using a Geographic Information System, through satellite photographs of the Professional Unit Adolfo Lop...This paper shows the procedure to obtain a continuous coverage map based on a collection of power meas- urements using a Geographic Information System, through satellite photographs of the Professional Unit Adolfo Lopez Mateos, and a group of punctual samples of the power of the Common Pilot Channel (CPICH);which is used to estimate the radio communications channel conditions, taken at different positions and dis- tances. These samples were taken using specialized equipment to obtain georeferenced measurements, and by a technique of statistical prediction, as the Krige Method, generate continuous coverage maps, making it possible to know the distribution of power, and therefore understanding the behavior and configuration of a Base Station, which in third generation cellular systems is also called Node B.展开更多
Terahertz(THz)and millimeter Wave(mmWave)have been considered as potential frequency bands for 6G cellular systems to meet the need of ultra-high data rates.However,indoor communications could be blocked in THz/mmW ce...Terahertz(THz)and millimeter Wave(mmWave)have been considered as potential frequency bands for 6G cellular systems to meet the need of ultra-high data rates.However,indoor communications could be blocked in THz/mmW cellular systems due to the high free-space propagation loss.Deploying a large number of small base stations indoors has been considered as a promising solution for solving indoor coverage problems.However,base station dense deployment leads to a significant increase in system energy consumption.In this paper,we develop a novel ultra-e˙icient energy-saving mechanism with the aim of reducing energy consumption in 6G distributed indoor base station scenarios.Unlike the existing relevant protocol framework of 3GPP,which operates the cellular system based on constant system signaling messages(including cell ID,cell reselection information,etc.),the proposed mechanism eliminates the need for system messages.The intuition comes from the observation that the probability of having no users within the coverage area of an indoor base station is high,hence continuously sending system messages to guarantee the quality of service is unnecessary in indoor scenarios.Specifically,we design a dedicated beacon signal to detect whether there are users in the coverage area of the base station and switch offthe main communication module when there are no active users for energy saving.The beacon frame structure is carefully designed based on the existing 3GPP specifications with minimal protocol modifications,and the protocol parameters involved are optimized.Simulation results show that the proposed mechanism can reduce the system energy from the order of tens of watts to the order of hundreds of milliwatts.Compared to traditional energy-saving schemes,the proposed mechanism achieves an average energy-saving gain of 58%,with a peak energy-saving gain of 90%.展开更多
基金supported in part by the National Key R&D Program of China under Grant 2020YFB1806100in part by the Natural Science Foundation of China under Grants U19B2025, 62121001, 62001347, and 61801361。
文摘The rapid development and continuous updating of the mega satellite constellation(MSC)have brought new visions for the future 6G coverage extension, where the global seamless signal coverage can realize ubiquitous services for user terminals. However, global traffic demands present nonuniform characteristics. Therefore, how to ensure the on-demand service coverage for the specific traffic demand, i.e., the ratio of traffic density to service requirement per unit area, is the core issue of 6G wireless coverage extension exploiting the MSC. To this regard, this paper first discusses the open challenges to reveal the future direction of 6G wireless coverage extension from the perspective of key factors affecting service coverage performance, i.e., the network access capacity, space segment capacity and their matchingrelationship. Furthermore, we elaborate on the key factors affecting effective matchings of the aforementioned aspects, thereby improving service coverage capability.
基金supported in part by the National Natural Science Foundation of China under Grant No.61671145the Key R&D Program of Jiangsu Province of China under Grant BE2018121
文摘Millimeter-wave(mm Wave) communications will be used in fifth-generation(5G) mobile communication systems, but they experience severe path loss and have high sensitivity to physical objects, leading to smaller cell radii and complicated network architectures. A coverage extension scheme using large-scale antenna arrays(LSAAs) has been suggested and theoretically proven to be cost-efficient in combination with ultradense small cell networks. To analyze and optimize the LSAA-based network deployments, a comprehensive survey of recent advances in statistical mmWave channel modeling is first presented in terms of channel parameter estimation, large-scale path loss models, and small-scale cluster models. Next, the measurement and modeling results at two 5G candidate mmWave bands(e.g., 28 GHz and 39 GHz) are reviewed and compared in several outdoor scenarios of interest, where the propagation characteristics make crucial contributions to wireless network designs. Finally, the coverage behaviors of systems employing a large number of antenna arrays are discussed, as well as some implications on future mmWave cellular network designs.
文摘This paper shows the procedure to obtain a continuous coverage map based on a collection of power meas- urements using a Geographic Information System, through satellite photographs of the Professional Unit Adolfo Lopez Mateos, and a group of punctual samples of the power of the Common Pilot Channel (CPICH);which is used to estimate the radio communications channel conditions, taken at different positions and dis- tances. These samples were taken using specialized equipment to obtain georeferenced measurements, and by a technique of statistical prediction, as the Krige Method, generate continuous coverage maps, making it possible to know the distribution of power, and therefore understanding the behavior and configuration of a Base Station, which in third generation cellular systems is also called Node B.
基金supported by the National Natural Science Foundation of China under Grant No.62201121the Fundamental Fundamental Research Funds for Central Universities under Grant No.ZYGX2024XJ070。
文摘Terahertz(THz)and millimeter Wave(mmWave)have been considered as potential frequency bands for 6G cellular systems to meet the need of ultra-high data rates.However,indoor communications could be blocked in THz/mmW cellular systems due to the high free-space propagation loss.Deploying a large number of small base stations indoors has been considered as a promising solution for solving indoor coverage problems.However,base station dense deployment leads to a significant increase in system energy consumption.In this paper,we develop a novel ultra-e˙icient energy-saving mechanism with the aim of reducing energy consumption in 6G distributed indoor base station scenarios.Unlike the existing relevant protocol framework of 3GPP,which operates the cellular system based on constant system signaling messages(including cell ID,cell reselection information,etc.),the proposed mechanism eliminates the need for system messages.The intuition comes from the observation that the probability of having no users within the coverage area of an indoor base station is high,hence continuously sending system messages to guarantee the quality of service is unnecessary in indoor scenarios.Specifically,we design a dedicated beacon signal to detect whether there are users in the coverage area of the base station and switch offthe main communication module when there are no active users for energy saving.The beacon frame structure is carefully designed based on the existing 3GPP specifications with minimal protocol modifications,and the protocol parameters involved are optimized.Simulation results show that the proposed mechanism can reduce the system energy from the order of tens of watts to the order of hundreds of milliwatts.Compared to traditional energy-saving schemes,the proposed mechanism achieves an average energy-saving gain of 58%,with a peak energy-saving gain of 90%.
