Due to the unprecedented rate of transformation in thefield of wireless communication industry,there is a need to prioritise the coverage,network power and throughput as preconditions.In Heterogeneous Networks(HetNets...Due to the unprecedented rate of transformation in thefield of wireless communication industry,there is a need to prioritise the coverage,network power and throughput as preconditions.In Heterogeneous Networks(HetNets)the low power node inclusion like Femto and Pico cells creates a network of Multi-Tier(M-Tier)which is regarded as the most significant strategy for enhancing the coverage,throughput,4G Long Term Evolution(LTE)ability.This work mainly focuses on M-Tier 3D Heterogeneous Networks Energy Efficiency(EE)based Carrier Aggregation(CA)scheme for streaming real-time huge data like images.Atfirst,M-Tier 3D HetNets scheme was made for investigating Signal to Noise Interference Ratio(SNIR)on assessing the collective Pico-tier and Femto-tier interference.Next,the scheme of channel allocation is scrutinised so as to esti-mate throughput from the multiple tiers.Additionally,with the use of CA technique,the problem of energy efficiency for M-Tier 3D Heterogeneous Network(HetNet)in relation to energy metrics and throughput was evaluated with the use of LTE and Wireless Fidelity(Wi-Fi)coexistence.The simulation is carried out in a MATLAB setting,and the outcomes reveal a huge impact on EE.The simulation is carried in terms of EE,transmission time,throughput,packet success rate,convergence probability,and coverage region.The analysis from simu-lation shows that on improving the output of the device,interference among small cell base stations is reduced on increasing EE.The outcomes attained aid in the effective creation of M-Tier 3D HetNets for enhancing EE by employing Multi-Stream Carrier Aggregation(MSCA)in HetNets.展开更多
In this work, we conduct a research on the effects of the details of the terrain on the path establishment in wireless networks. We discuss how the terrain induced variations, that are unavoidably caused by the obstru...In this work, we conduct a research on the effects of the details of the terrain on the path establishment in wireless networks. We discuss how the terrain induced variations, that are unavoidably caused by the obstructions and irregularities in the surroundings of the transmitting and the receiving antennas, have two distinct effects on the network. Firstly, they reduce the amount of links in the network connectivity graph causing it to behave more randomly, while decreasing the coverage and capacity of the network. Secondly, they increase the length of the established paths between the nodes. The presented results show how the terrain oblique influences the layout of the network connectivity graph, in terms of different network metrics, and gives insight to the appropriate level of details needed to describe the terrain in order to obtain results that will be satisfyingly accurate.展开更多
Understanding the molecular packing arrangement and aggregation behaviors of organic semiconductor materials is crucial in comprehending their unique properties,particularly in complex structures required for solution...Understanding the molecular packing arrangement and aggregation behaviors of organic semiconductor materials is crucial in comprehending their unique properties,particularly in complex structures required for solution processing in organic photovoltaics.However,there has been limited focus on studying the diverse self-assembly behaviors induced by varying molecular skeletons.To address this issue,we designed and synthesized i-9R4Cl,i-7R4Cl,and 7R4Cl with nine-and seven-membered ring backbones,respectively.The single crystal structures revealed a standard H-type aggregate in i-9R4Cl,which is rare fully face-to-face packing in nonfullerene acceptors.Conversely,i-7R4Cl exhibited a typical J-type aggregate,while 7R4Cl demonstrated a synergistic H/J-type aggregate as conventional Y-series acceptors.Moreover,it reveals a unique three-dimensional(3D)network packing structure dominated by H-aggregation in i-9R4Cl,a linear packing structure in i-7R4Cl,and an elliptical 3D network packing structure in 7R4Cl.The grazing incidence wide-angle X-ray scattering tests confirmed that the packing arrangement in crystal structures was preserved in the film state.Despite i-9R4Cl’s favorable properties in stacking,it achieved a lower power conversion efficiency(PCE)of 1.97%compared to the other two acceptors,which should be attributed to poor exciton separation and carrier recombination induced by the morphology of aggregation regulation.Surprisingly,the electron paramagnetic resonance indicates that i-9R4Cl possesses radical properties,and when introduced as the third component in the PBDB-TF:BTIC-C9-4Cl based devices,it led to an enhancement in PCE from 18.42%to 19.08%,making it one of the highest efficiencies based on the BTIC-C9-4Cl system.It underscores how even subtle changes in molecular structure can significantly impact material properties.Our work aims to control the aggregation states of molecules,transitioning from standard H-type to J-type and to synergistic H/J-type aggregates,subsequently investigating the corresponding relationship between aggregation states,material properties,and devices performance.This is critical for designing new acceptor materials to overcome the bottlenecks in efficiency.展开更多
文摘Due to the unprecedented rate of transformation in thefield of wireless communication industry,there is a need to prioritise the coverage,network power and throughput as preconditions.In Heterogeneous Networks(HetNets)the low power node inclusion like Femto and Pico cells creates a network of Multi-Tier(M-Tier)which is regarded as the most significant strategy for enhancing the coverage,throughput,4G Long Term Evolution(LTE)ability.This work mainly focuses on M-Tier 3D Heterogeneous Networks Energy Efficiency(EE)based Carrier Aggregation(CA)scheme for streaming real-time huge data like images.Atfirst,M-Tier 3D HetNets scheme was made for investigating Signal to Noise Interference Ratio(SNIR)on assessing the collective Pico-tier and Femto-tier interference.Next,the scheme of channel allocation is scrutinised so as to esti-mate throughput from the multiple tiers.Additionally,with the use of CA technique,the problem of energy efficiency for M-Tier 3D Heterogeneous Network(HetNet)in relation to energy metrics and throughput was evaluated with the use of LTE and Wireless Fidelity(Wi-Fi)coexistence.The simulation is carried out in a MATLAB setting,and the outcomes reveal a huge impact on EE.The simulation is carried in terms of EE,transmission time,throughput,packet success rate,convergence probability,and coverage region.The analysis from simu-lation shows that on improving the output of the device,interference among small cell base stations is reduced on increasing EE.The outcomes attained aid in the effective creation of M-Tier 3D HetNets for enhancing EE by employing Multi-Stream Carrier Aggregation(MSCA)in HetNets.
文摘In this work, we conduct a research on the effects of the details of the terrain on the path establishment in wireless networks. We discuss how the terrain induced variations, that are unavoidably caused by the obstructions and irregularities in the surroundings of the transmitting and the receiving antennas, have two distinct effects on the network. Firstly, they reduce the amount of links in the network connectivity graph causing it to behave more randomly, while decreasing the coverage and capacity of the network. Secondly, they increase the length of the established paths between the nodes. The presented results show how the terrain oblique influences the layout of the network connectivity graph, in terms of different network metrics, and gives insight to the appropriate level of details needed to describe the terrain in order to obtain results that will be satisfyingly accurate.
基金supported by the National Natural Science Foundation of China(grant nos.22225504,22305112,and 22305114)Guangdong Provincial Key Laboratory of Catalysis(grant no.2020B121201002)+2 种基金Shenzhen Fundamental Research Program(grant no.JCYJ20210324120010028)China Postdoctoral Science Foundation(grant no.2022M721466)High level of special funds(grant no.G03050K002).
文摘Understanding the molecular packing arrangement and aggregation behaviors of organic semiconductor materials is crucial in comprehending their unique properties,particularly in complex structures required for solution processing in organic photovoltaics.However,there has been limited focus on studying the diverse self-assembly behaviors induced by varying molecular skeletons.To address this issue,we designed and synthesized i-9R4Cl,i-7R4Cl,and 7R4Cl with nine-and seven-membered ring backbones,respectively.The single crystal structures revealed a standard H-type aggregate in i-9R4Cl,which is rare fully face-to-face packing in nonfullerene acceptors.Conversely,i-7R4Cl exhibited a typical J-type aggregate,while 7R4Cl demonstrated a synergistic H/J-type aggregate as conventional Y-series acceptors.Moreover,it reveals a unique three-dimensional(3D)network packing structure dominated by H-aggregation in i-9R4Cl,a linear packing structure in i-7R4Cl,and an elliptical 3D network packing structure in 7R4Cl.The grazing incidence wide-angle X-ray scattering tests confirmed that the packing arrangement in crystal structures was preserved in the film state.Despite i-9R4Cl’s favorable properties in stacking,it achieved a lower power conversion efficiency(PCE)of 1.97%compared to the other two acceptors,which should be attributed to poor exciton separation and carrier recombination induced by the morphology of aggregation regulation.Surprisingly,the electron paramagnetic resonance indicates that i-9R4Cl possesses radical properties,and when introduced as the third component in the PBDB-TF:BTIC-C9-4Cl based devices,it led to an enhancement in PCE from 18.42%to 19.08%,making it one of the highest efficiencies based on the BTIC-C9-4Cl system.It underscores how even subtle changes in molecular structure can significantly impact material properties.Our work aims to control the aggregation states of molecules,transitioning from standard H-type to J-type and to synergistic H/J-type aggregates,subsequently investigating the corresponding relationship between aggregation states,material properties,and devices performance.This is critical for designing new acceptor materials to overcome the bottlenecks in efficiency.
