In this paper, an energy efficient bandwidth allocation scheme is proposed for wireless communication systems. An optimal bandwidth expansion（OBE） scheme is proposed to assign the available system bandwidth for user...In this paper, an energy efficient bandwidth allocation scheme is proposed for wireless communication systems. An optimal bandwidth expansion（OBE） scheme is proposed to assign the available system bandwidth for users. When the system bandwidth does not reach the full load, the remaining bandwidth can be energy-efficiently assigned to the other users. Simulation results show that the energy efficiency of the proposed OBE scheme outperforms the traditional same bandwidth expansion（SBE） scheme. Thus, the proposed OBE can effectively assign the system bandwidth and improve energy efficiency.展开更多
A quality of service（QoS） guaranteed cross-layer resource allocation algorithm with physical layer, medium access control（MAC） layer and call admission control（CAC） considered simultaneously is proposed for the ...A quality of service（QoS） guaranteed cross-layer resource allocation algorithm with physical layer, medium access control（MAC） layer and call admission control（CAC） considered simultaneously is proposed for the full IP orthogonal frequency division multiple access（OFDMA） communication system, which can ensure the quality of multimedia services in full IP networks.The algorithm converts the physical layer resources such as subcarriers, transmission power, and the QoS metrics into equivalent bandwidth which can be distributed by the base station in all three layers. By this means, the QoS requirements in terms of bit error rate（BER）, transmission delay and dropping probability can be guaranteed by the cross-layer optimal equivalent bandwidth allocation. The numerical results show that the proposed algorithm has higher spectrum efficiency compared to the existing systems.展开更多
Hybrid coordination function controlled channel access(HCCA)applied in wireless ad hoc network systems is the strategy to allocate the bandwidth resources of control channel(CCH)and service channels(SCHs).With the con...Hybrid coordination function controlled channel access(HCCA)applied in wireless ad hoc network systems is the strategy to allocate the bandwidth resources of control channel(CCH)and service channels(SCHs).With the continuous development of Internet of vehicles(IoV)technologies,it is difficult for HCCA to support traffic information services,such as low delay along with high-frequency dissemination of security beacons and large capacity interaction of image data.Fusing the fundamental theories of No.7 signaling system and 5G-IoV technologies,this paper proposes a novel channel bandwidth allocation strategy named CO-HCCA,which matches CCH time slot numbers with on board units(OBUs)numbers to reduce the congestion of channel access demand information(CADI);and also illustrates a dynamic segment adjusting algorithm of the time slots.On one hand,in the channel reservation stage of CCH control cycle,OBUs are sorted according to the priority of data transmission,and then the corresponding transmission slots are adopted orderly according to the OBUs numbers,so as to decrease the collision probability of high-frequency dissemination of CADI.On the other hand,for the quickly arriving and leaving OBUs in coverage of roadside base station(RBS),the prediction of bandwidth segments is dynamically adjusted to adapt to the time-varying characteristic of the connected vehicle scenarios.Modeling calculation and objective comparison on OMNeT++computing platform show that the proposed CO-HCCA strategy can effectively reduce the channel congestion of IoV,and in the scenario of high-density data interaction,it is beneficial to promote the transmission timeliness of security beacons and the package delivery rate(PDR)of high bit-rate multiple information.展开更多
Since the scarcity of bandwidth resources has become increasingly critical in modern communication systems,orbital angular momentum(OAM)with a higher degree of freedom in information modulation has become a promising ...Since the scarcity of bandwidth resources has become increasingly critical in modern communication systems,orbital angular momentum(OAM)with a higher degree of freedom in information modulation has become a promising solution to alleviate the shortage of spectrum resources.Consequently,the integration of OAM with millimeter-wave technology has emerged as a focal point in next-generation communication research.Recently,programmable metasurfaces have gained considerable attention as essential devices for OAM generation due to real-time tunability,but their profiles are relatively high as a result of the external feed source.This paper proposes a conformal radiation-type programmable metasurface operating in the millimeter-wave band.By employing a series–parallel hybrid feed network to replace conventional external feed sources,the overall profile of the metasurface system can be reduced to less than 0.1λ.Furthermore,the proposed innovation design could also achieve a conformal cross-shaped architecture,which is ultraportable and very effective in integrating with the front ends of satellites or aircraft and eliminating issues such as feed source blockage as well as energy spillover losses in conventional metasurfaces.The proposed metasurface could achieve a realized gain of 22.54 dB with an aperture efficiency of 21.75%,thus generating high-purity OAM waves with topological charges of l=0,l=+1,l=+2,and l=+3.Additionally,by incorporating beam scanning techniques,OAM waves could be deflected to accommodate scenarios with moving receivers,demonstrating substantial potential for future high-speed wireless communication applications.展开更多
基金supported by the NSC under Grant No.101-2221-E-324-024
文摘In this paper, an energy efficient bandwidth allocation scheme is proposed for wireless communication systems. An optimal bandwidth expansion（OBE） scheme is proposed to assign the available system bandwidth for users. When the system bandwidth does not reach the full load, the remaining bandwidth can be energy-efficiently assigned to the other users. Simulation results show that the energy efficiency of the proposed OBE scheme outperforms the traditional same bandwidth expansion（SBE） scheme. Thus, the proposed OBE can effectively assign the system bandwidth and improve energy efficiency.
基金supported by the National Natural Science Foundation of China(61271235)the Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions-Information and Communication Engineering
文摘A quality of service（QoS） guaranteed cross-layer resource allocation algorithm with physical layer, medium access control（MAC） layer and call admission control（CAC） considered simultaneously is proposed for the full IP orthogonal frequency division multiple access（OFDMA） communication system, which can ensure the quality of multimedia services in full IP networks.The algorithm converts the physical layer resources such as subcarriers, transmission power, and the QoS metrics into equivalent bandwidth which can be distributed by the base station in all three layers. By this means, the QoS requirements in terms of bit error rate（BER）, transmission delay and dropping probability can be guaranteed by the cross-layer optimal equivalent bandwidth allocation. The numerical results show that the proposed algorithm has higher spectrum efficiency compared to the existing systems.
基金the National Natural Science Foundation of China under Grant 61573171。
文摘Hybrid coordination function controlled channel access(HCCA)applied in wireless ad hoc network systems is the strategy to allocate the bandwidth resources of control channel(CCH)and service channels(SCHs).With the continuous development of Internet of vehicles(IoV)technologies,it is difficult for HCCA to support traffic information services,such as low delay along with high-frequency dissemination of security beacons and large capacity interaction of image data.Fusing the fundamental theories of No.7 signaling system and 5G-IoV technologies,this paper proposes a novel channel bandwidth allocation strategy named CO-HCCA,which matches CCH time slot numbers with on board units(OBUs)numbers to reduce the congestion of channel access demand information(CADI);and also illustrates a dynamic segment adjusting algorithm of the time slots.On one hand,in the channel reservation stage of CCH control cycle,OBUs are sorted according to the priority of data transmission,and then the corresponding transmission slots are adopted orderly according to the OBUs numbers,so as to decrease the collision probability of high-frequency dissemination of CADI.On the other hand,for the quickly arriving and leaving OBUs in coverage of roadside base station(RBS),the prediction of bandwidth segments is dynamically adjusted to adapt to the time-varying characteristic of the connected vehicle scenarios.Modeling calculation and objective comparison on OMNeT++computing platform show that the proposed CO-HCCA strategy can effectively reduce the channel congestion of IoV,and in the scenario of high-density data interaction,it is beneficial to promote the transmission timeliness of security beacons and the package delivery rate(PDR)of high bit-rate multiple information.
基金supported by the Gusu Leading Talents of Innovation and Entrepreneurship(ZXL2024332)the National Natural Science Foundation of China(62471399 and 62401474)+3 种基金the Shanghai Aerospace Science and Technology Innovation Foundation(SAST2023-021)the Basic Research Programs of Taicang(TC2022JC16)the Shanghai Kewei Foundation(22JC1404000 and 24DP1500500)the National Key Research and Development Program of China(2022YFB3806000).
文摘Since the scarcity of bandwidth resources has become increasingly critical in modern communication systems,orbital angular momentum(OAM)with a higher degree of freedom in information modulation has become a promising solution to alleviate the shortage of spectrum resources.Consequently,the integration of OAM with millimeter-wave technology has emerged as a focal point in next-generation communication research.Recently,programmable metasurfaces have gained considerable attention as essential devices for OAM generation due to real-time tunability,but their profiles are relatively high as a result of the external feed source.This paper proposes a conformal radiation-type programmable metasurface operating in the millimeter-wave band.By employing a series–parallel hybrid feed network to replace conventional external feed sources,the overall profile of the metasurface system can be reduced to less than 0.1λ.Furthermore,the proposed innovation design could also achieve a conformal cross-shaped architecture,which is ultraportable and very effective in integrating with the front ends of satellites or aircraft and eliminating issues such as feed source blockage as well as energy spillover losses in conventional metasurfaces.The proposed metasurface could achieve a realized gain of 22.54 dB with an aperture efficiency of 21.75%,thus generating high-purity OAM waves with topological charges of l=0,l=+1,l=+2,and l=+3.Additionally,by incorporating beam scanning techniques,OAM waves could be deflected to accommodate scenarios with moving receivers,demonstrating substantial potential for future high-speed wireless communication applications.
