In order to forecast promising technologies in the field of next generation mobile communication, various patent indicators were analyzed such as citation per patent, patent family information, patent share, increase ...In order to forecast promising technologies in the field of next generation mobile communication, various patent indicators were analyzed such as citation per patent, patent family information, patent share, increase rate, and patent activity. These indicators were quantified into several indexes and then integrated into an evaluation score to provide promising technologies. As a result of the suggested patent analysis, four technologies out of twenty two in details classification were selected, which showed outstanding technology competitiveness, high patent share and increasing rates as well as high recent-patent-ratios and triad-patent-family-ratios. Each of the selected technologies scored more than 10 points in total, and the following four technologies were suggested as promising ones in the field of next generation mobile communication: 1) 3GPP based mobile communication, 2) beyond 4G mobile communication, 3) IEEE 802.16 based mobile communication, which are in medium classification of broadband mobile communication system, and 4) testing/certification system of mobile communication, which is in medium classification of mobile communication testing/certification system.展开更多
The deployment of underwater networks allows researchers to collect explorative and monitoring data on underwater ecosystems.The acoustic medium has been widely adopted in current research and commercial uses,while th...The deployment of underwater networks allows researchers to collect explorative and monitoring data on underwater ecosystems.The acoustic medium has been widely adopted in current research and commercial uses,while the optical medium remains experimental only.According to our survey onthe properties of acoustic and optical communicationsand preliminary simulation results have shown significant trade-offs between bandwidth,propagation delay,power consumption,and effective communication range.We propose a hybrid solution that combines the use of acoustic and optical communication in order to overcome the bandwidth limitation of the acoustic channel by enabling optical communicationwith the help of acoustic-assisted alignment between optical transmitters and receivers.展开更多
The detection performance is evaluated for our proposed analog multiuser receiver in Ultra-WideBand (UWB) transmitted-reference system. In the presence of dense multipath and multi-access signals,the performance analy...The detection performance is evaluated for our proposed analog multiuser receiver in Ultra-WideBand (UWB) transmitted-reference system. In the presence of dense multipath and multi-access signals,the performance analysis is difficult due to the complicated waveform of received impulse. We develop an approach to analyze the steady-state Signal-to-Interference-plus-Noise (SINR) of the detector output. The multipath-spread impulse is fitted to an exponentially decaying profile in the analysis. A closed-form expression of steady-state SINR is further deduced for the proposed Least Minimum Square (LMS) detector. The analysis is validated by simulations in Line-Of-Sight (LOS) and Non-Line-Of-Sight (NLOS) channel respectively. Based on the theoretical results,the multipath delay spread is employed to determine the optimal width of the integration window of the detector.展开更多
For impulse radio ultra-wideband (IR-UWB) ranging systems,effects of the settings of transmitter-related parameters, which include the pulse shape, the bandwidth and the pulse repetition interval (PRI), on ranging acc...For impulse radio ultra-wideband (IR-UWB) ranging systems,effects of the settings of transmitter-related parameters, which include the pulse shape, the bandwidth and the pulse repetition interval (PRI), on ranging accuracy were studied through theoretical analysis and simulations. Both the match-filtering based coherent TOA estimation algorithm and the energy-detection based non-coherent algorithm were used during simulations. Results show that the pulse shape has the least effect on the ranging accuracy. Increasing the pulse bandwidth can improve the ranging performance, but the performance is hardly improved any more when the bandwidth is increased beyond a certain level. PRI should be set long enough to guarantee the accurate ranging, because when PRI is shorter than the maximum excess delay of the channel, the ranging accuracy will be deteriorated by inter-pulse interference.展开更多
In this paper,we propose a wireless channel testing method and construct the test platform for the Gbps broadband wireless system.The proposed method is implemented to evaluate the transmission performance according t...In this paper,we propose a wireless channel testing method and construct the test platform for the Gbps broadband wireless system.The proposed method is implemented to evaluate the transmission performance according to the acquired field test results.The results have shown that the proposed channel test algorithm is valid and efficient,which can continuously show the variation of system throughput,frame loss rate and latency.展开更多
In this paper we study the influence of the relative phase between .the probe and driving fields on propagation effect in an open Doppler broadening V-type three-level atomic system with spontaneously generated cohere...In this paper we study the influence of the relative phase between .the probe and driving fields on propagation effect in an open Doppler broadening V-type three-level atomic system with spontaneously generated coherence （SGC） by using the calculation resuk of the density matrix motion equations and the propagation equations of the driving and probe fields. It is shown that the relative phase （Ф） has remarkable periodical influence on the propagation effect, and the period is 2π. By selecting appropriate value of Ф, we can get larger lasing without inversion （LW1） gain and longer propagation distance in which gain exists, and hence obtain higher probe field （i.e. LWI） intensity. When Ф=π/2, the largest LWI gain and probe field intensity can be got. In addition, the atomic exit rate （γ0） and ratio （S） of the atomic injection rates also have a considerable modulation role on the phase-dependent propagation effect. In certain value range of Y0 （S）, LWI gain and probe field intensity increase with γ0 （S） increasing. In the open system, LWI gain and probe field intensity much larger than those in the corresponding closed system can be obtained.展开更多
文摘In order to forecast promising technologies in the field of next generation mobile communication, various patent indicators were analyzed such as citation per patent, patent family information, patent share, increase rate, and patent activity. These indicators were quantified into several indexes and then integrated into an evaluation score to provide promising technologies. As a result of the suggested patent analysis, four technologies out of twenty two in details classification were selected, which showed outstanding technology competitiveness, high patent share and increasing rates as well as high recent-patent-ratios and triad-patent-family-ratios. Each of the selected technologies scored more than 10 points in total, and the following four technologies were suggested as promising ones in the field of next generation mobile communication: 1) 3GPP based mobile communication, 2) beyond 4G mobile communication, 3) IEEE 802.16 based mobile communication, which are in medium classification of broadband mobile communication system, and 4) testing/certification system of mobile communication, which is in medium classification of mobile communication testing/certification system.
基金supported in part by the US National Science Foundation under Grant No. 1205757 Northrop Grumman Corporation
文摘The deployment of underwater networks allows researchers to collect explorative and monitoring data on underwater ecosystems.The acoustic medium has been widely adopted in current research and commercial uses,while the optical medium remains experimental only.According to our survey onthe properties of acoustic and optical communicationsand preliminary simulation results have shown significant trade-offs between bandwidth,propagation delay,power consumption,and effective communication range.We propose a hybrid solution that combines the use of acoustic and optical communication in order to overcome the bandwidth limitation of the acoustic channel by enabling optical communicationwith the help of acoustic-assisted alignment between optical transmitters and receivers.
基金Supported by the Guangxi Natural Science Foundation (No.0731025, No.0731026)the Established Project by Guangxi Education Department (No.200808LX117)
文摘The detection performance is evaluated for our proposed analog multiuser receiver in Ultra-WideBand (UWB) transmitted-reference system. In the presence of dense multipath and multi-access signals,the performance analysis is difficult due to the complicated waveform of received impulse. We develop an approach to analyze the steady-state Signal-to-Interference-plus-Noise (SINR) of the detector output. The multipath-spread impulse is fitted to an exponentially decaying profile in the analysis. A closed-form expression of steady-state SINR is further deduced for the proposed Least Minimum Square (LMS) detector. The analysis is validated by simulations in Line-Of-Sight (LOS) and Non-Line-Of-Sight (NLOS) channel respectively. Based on the theoretical results,the multipath delay spread is employed to determine the optimal width of the integration window of the detector.
基金Sponsored by the National Natural Science Foundation of China (Grant No.60432040)the Natural Science Foundation of Guangdong Privince(Grant No.9451805707003235)
文摘For impulse radio ultra-wideband (IR-UWB) ranging systems,effects of the settings of transmitter-related parameters, which include the pulse shape, the bandwidth and the pulse repetition interval (PRI), on ranging accuracy were studied through theoretical analysis and simulations. Both the match-filtering based coherent TOA estimation algorithm and the energy-detection based non-coherent algorithm were used during simulations. Results show that the pulse shape has the least effect on the ranging accuracy. Increasing the pulse bandwidth can improve the ranging performance, but the performance is hardly improved any more when the bandwidth is increased beyond a certain level. PRI should be set long enough to guarantee the accurate ranging, because when PRI is shorter than the maximum excess delay of the channel, the ranging accuracy will be deteriorated by inter-pulse interference.
基金supported by International Scientific and Technological Cooperation Program from MOST.(No.S2010GR0902)the Science and Technology Innovation Program of Shanghai(No.09dz2201100)+1 种基金Equipment Functional Development of Technological Innovation Projects from CAS(No.YG2010060)Research Fund of National Mobile Communications Research Laboratory,Southeast University(No.2009A04)
文摘In this paper,we propose a wireless channel testing method and construct the test platform for the Gbps broadband wireless system.The proposed method is implemented to evaluate the transmission performance according to the acquired field test results.The results have shown that the proposed channel test algorithm is valid and efficient,which can continuously show the variation of system throughput,frame loss rate and latency.
基金supported by the National Natural Science Foundation of China(No.10875072)
文摘In this paper we study the influence of the relative phase between .the probe and driving fields on propagation effect in an open Doppler broadening V-type three-level atomic system with spontaneously generated coherence （SGC） by using the calculation resuk of the density matrix motion equations and the propagation equations of the driving and probe fields. It is shown that the relative phase （Ф） has remarkable periodical influence on the propagation effect, and the period is 2π. By selecting appropriate value of Ф, we can get larger lasing without inversion （LW1） gain and longer propagation distance in which gain exists, and hence obtain higher probe field （i.e. LWI） intensity. When Ф=π/2, the largest LWI gain and probe field intensity can be got. In addition, the atomic exit rate （γ0） and ratio （S） of the atomic injection rates also have a considerable modulation role on the phase-dependent propagation effect. In certain value range of Y0 （S）, LWI gain and probe field intensity increase with γ0 （S） increasing. In the open system, LWI gain and probe field intensity much larger than those in the corresponding closed system can be obtained.
