In order to guarantee the overall return on investment (ROI), improve user experience and quality of service (QoS), save energy, reduce electra magnetic interference (EMI) and radiation pollution, and enable the susta...In order to guarantee the overall return on investment (ROI), improve user experience and quality of service (QoS), save energy, reduce electra magnetic interference (EMI) and radiation pollution, and enable the sustainable deployment of new profitable applications and services in heterogeneous wireless networks coexistence reality, this paper proposes a cross-network cooperation mechanism to effectively share network resources and infrastructures, and then adaptively control and match multi-network energy distribution characteristics according to actual user/service requirements in different geographic areas. Some idle or lightly-loaded base stations (BS or BSs) will be temporally turned off for saving energy and reducing EMI. Initial simulation results show that the proposed approach can significantly improve the overall energy efficiency and QoS performance across multiple cooperative wireless networks.展开更多
Traditional mobile communication systems mainly work on the licensed frequency band near or below 3 GHz;however,this band is becoming increasingly crowded.On the other hand,there are abundant unlicensed spectrum resou...Traditional mobile communication systems mainly work on the licensed frequency band near or below 3 GHz;however,this band is becoming increasingly crowded.On the other hand,there are abundant unlicensed spectrum resources in higher frequency bands,e.g.,6 GHz,15 GHz,and 28 GHz,and if those bands are applied,the current spectrum shortage problem could be effectively alleviated.However,the wireless channel characteristics and models are important but still unknown,and thus in this study,extensive measurements and modeling have been conducted to study the characteristics of the high-frequency 15-GHz band.Specifically,a PN(Pseudo Noise)sequence based time-domain measurement system was built and applied to measure the propagation characteristics of the LOS(Line-of-Sight)and NLOS(Non-Line-of-Sight)scenarios in an indoor corridor at 15 GHz.Then,in-depth analysis and modeling on the large-scale characteristics of wireless channels,the relationship between distance and path loss,the path loss exponent,and the shadow fading standard variance are provided.Moreover,the relationship between received power and different elevation angles was studied.In the measurement,two 25-dBi horn antennas with a 10 half-power beam width are used to change elevation angles in the transmitting terminal and azimuth angles in the receiving terminal for all measurement points.The findings and results in this work will serve as a reference and basis for future theoretical studies of the 15-GHz band.展开更多
基金supported by the National Natural Science Foundation of China ( NSFC)( No. 60902041)Chinese Academy of Sciences ( No. 2010045)the Ministry of Science and Technology( MOST) of China ( No. 2010DFB10410,No. 2009DFB13080 and No. 2009ZX03003-009)
文摘In order to guarantee the overall return on investment (ROI), improve user experience and quality of service (QoS), save energy, reduce electra magnetic interference (EMI) and radiation pollution, and enable the sustainable deployment of new profitable applications and services in heterogeneous wireless networks coexistence reality, this paper proposes a cross-network cooperation mechanism to effectively share network resources and infrastructures, and then adaptively control and match multi-network energy distribution characteristics according to actual user/service requirements in different geographic areas. Some idle or lightly-loaded base stations (BS or BSs) will be temporally turned off for saving energy and reducing EMI. Initial simulation results show that the proposed approach can significantly improve the overall energy efficiency and QoS performance across multiple cooperative wireless networks.
基金supported by The National High Technology Research Development Program of China(863 Program)(No.2014AA01A706)The National Natural Science Foundation of China(No.61471346)+1 种基金The National Science and Technology Major Project(No.2014ZX03003012)The Science and Technology Commission of Shanghai Municipality(No.14DZ2281000).
文摘Traditional mobile communication systems mainly work on the licensed frequency band near or below 3 GHz;however,this band is becoming increasingly crowded.On the other hand,there are abundant unlicensed spectrum resources in higher frequency bands,e.g.,6 GHz,15 GHz,and 28 GHz,and if those bands are applied,the current spectrum shortage problem could be effectively alleviated.However,the wireless channel characteristics and models are important but still unknown,and thus in this study,extensive measurements and modeling have been conducted to study the characteristics of the high-frequency 15-GHz band.Specifically,a PN(Pseudo Noise)sequence based time-domain measurement system was built and applied to measure the propagation characteristics of the LOS(Line-of-Sight)and NLOS(Non-Line-of-Sight)scenarios in an indoor corridor at 15 GHz.Then,in-depth analysis and modeling on the large-scale characteristics of wireless channels,the relationship between distance and path loss,the path loss exponent,and the shadow fading standard variance are provided.Moreover,the relationship between received power and different elevation angles was studied.In the measurement,two 25-dBi horn antennas with a 10 half-power beam width are used to change elevation angles in the transmitting terminal and azimuth angles in the receiving terminal for all measurement points.The findings and results in this work will serve as a reference and basis for future theoretical studies of the 15-GHz band.
