Comprised by a swarm of acoustically linked and cooperative autonomous underwater vehicles(AUVs) with onboard sensors,an underwater mobile sensing network(UMSN) will be a complementary means to fixed observatory netwo...Comprised by a swarm of acoustically linked and cooperative autonomous underwater vehicles(AUVs) with onboard sensors,an underwater mobile sensing network(UMSN) will be a complementary means to fixed observatory networks,e.g.seafloor observatory networks and moored buoy arrays.It has obvious advantages over a single large AUV in higher efficiency due to parallel observation,stronger robustness to vehicle failures and lower cost.Although an UMSN can be viewed as a counterpart of wireless mobile sensing networks for air and terrestrial applications,it is much more challenging due to poor performance of underwater acoustic communication, poor performance of underwater positioning and high degree of uncertainty in vehicle dynamics and underwater environment.In order to verify key technologies involved in an UMSN,e.g.cooperation of multi-AUVs based on acoustic communication,a low cost testbed has been developed for experimental study.The design of both hardware and software is introduced.Also the results of a functional test for verification of the effectiveness of the testbed are presented.展开更多
A white-light interferometric fiber-optic sensing network based on the double-ring topology is demonstrated,which can be applied to the measurements of quasi-distributed strain and temperature in a smart structure.In ...A white-light interferometric fiber-optic sensing network based on the double-ring topology is demonstrated,which can be applied to the measurements of quasi-distributed strain and temperature in a smart structure.In order to increase the multiplexing capacity,decrease the measurement cost of each sensor,and improve the ability of reliability of the sensor network,a double-port interrogating technology was used.The double-ring fiber optical sensing network based on the space division multiplexing(SDM)is further developed.The low coherent multiplexing principle in the double-ring network structure is analyzed.Based on the optical path matching condition of SDM,the intensity characteristic of the interference signal in the sensor is deduced.The characteristics of the double-ring sensing network connecting 9 sensors and its property of robust resisting destruction are verified by experiments,and the results are analyzed and discussed.展开更多
Conference Theme-Anti-Crime Networking and Systems The 2007 IEEE International Conference on Networking,Sensing and Control will be held in London. The main theme of the conference is anti-crime networking and critica...Conference Theme-Anti-Crime Networking and Systems The 2007 IEEE International Conference on Networking,Sensing and Control will be held in London. The main theme of the conference is anti-crime networking and critical infrastructure.The area of anti- crime networking and critical infrastructure is a fusion of a number of research areas in networking, sensing,human factors,artificial intelligence,operational research,and systems control theory. However,the real challenge is to design anti-crime networking and systems from a holistic perspective; taking into account technical,organizational as well as contextual complexity.A system engineering approach is required to address new problems of this challenging and promising area.This conference will provide a remarkable opportunity for the academic and industrial community to address new challenges and share solutions,and discuss future research directions.It will feature plenary speeches, industrial panel sessions,funding agency panel sessions,interactive sessions,and invited/special sessions.Contributions are expected from academia,industry,EPSRC,EU,DTI,and MoD.Technical topics of the conference include but are not limited to:展开更多
Sensing in wireless local area network(WLAN) gains great interests recently. In this paper we focus on the multi-user WLAN sensing problem under the existing 802.11 standards. Multiple stations perform sensing with th...Sensing in wireless local area network(WLAN) gains great interests recently. In this paper we focus on the multi-user WLAN sensing problem under the existing 802.11 standards. Multiple stations perform sensing with the access point and transmit channel state information(CSI)report simultaneously on the basis of uplink-orthogonal frequency division multiple access(OFDMA). Considering the transmission resource consumed in CSI report and the padding wastage in OFDMA based CSI report, we optimize the CSI simplification and uplink resource unit(RU)allocation jointly, aiming to balance the sensing accuracy and padding wastage performances in WLAN sensing. We propose the minimize padding maximize efficiency(MPME) algorithm to solve the problem and evaluate the performance of the proposed algorithm through extensive simulations.展开更多
Fiber Bragg grating(FBG)array,consisting of a number of sensing units in a single optical fiber,can be practically applied in quasi-distributed sensing networks.Serious signal crosstalk occurring between large-serial ...Fiber Bragg grating(FBG)array,consisting of a number of sensing units in a single optical fiber,can be practically applied in quasi-distributed sensing networks.Serious signal crosstalk occurring between large-serial of identical FBGs,however,has limited the further increase in the number of sensing units,thus restricting applications only for short-distance sensing networks.To reduce the signal crosstalk,we design two novel types of 10-kilometer-long FBG arrays with 10000 equally spaced gratings,written on-line using a customized grating inscription system,which is affiliated to a drawing tower.Main factors causing signal crosstalk,such as spectral shadowing and multiple reflections,are firstly investigated in theory.Consistent with the theoretical findings,experimental results are proving that ultra-weak(the reflectivity of—40 dB)and multi-wavelength gratings of a number more than 10000 can be readily identified,with satisfied low crosstalk.The maximum attenuation of grating signal and minimum signal-to-noise ratio(SNR)in a single-wavelength array are 10.69 dB and 5.62 dB,respectively.As a comparison,by increasing the number of central wavelengths to three,the attenuation can be effectively reduced to 5.54dB and the minimum SNR has been improved to 8.14 dB.The current study significantly enhances the multiplexing capacity of FBG arrays and demonstrates promising potentials for establishing large-capacity quasi-distributed sensing networks.展开更多
基金the National High Technology Research and Development Program(863) of China (No.2006AA09Z233)
文摘Comprised by a swarm of acoustically linked and cooperative autonomous underwater vehicles(AUVs) with onboard sensors,an underwater mobile sensing network(UMSN) will be a complementary means to fixed observatory networks,e.g.seafloor observatory networks and moored buoy arrays.It has obvious advantages over a single large AUV in higher efficiency due to parallel observation,stronger robustness to vehicle failures and lower cost.Although an UMSN can be viewed as a counterpart of wireless mobile sensing networks for air and terrestrial applications,it is much more challenging due to poor performance of underwater acoustic communication, poor performance of underwater positioning and high degree of uncertainty in vehicle dynamics and underwater environment.In order to verify key technologies involved in an UMSN,e.g.cooperation of multi-AUVs based on acoustic communication,a low cost testbed has been developed for experimental study.The design of both hardware and software is introduced.Also the results of a functional test for verification of the effectiveness of the testbed are presented.
基金supported by the Teaching and Research Award Program for Outstanding Young Professors in Higher Education Institute from the Ministry of Education of China and National Natural Science Foundation of China(No.60577005).
文摘A white-light interferometric fiber-optic sensing network based on the double-ring topology is demonstrated,which can be applied to the measurements of quasi-distributed strain and temperature in a smart structure.In order to increase the multiplexing capacity,decrease the measurement cost of each sensor,and improve the ability of reliability of the sensor network,a double-port interrogating technology was used.The double-ring fiber optical sensing network based on the space division multiplexing(SDM)is further developed.The low coherent multiplexing principle in the double-ring network structure is analyzed.Based on the optical path matching condition of SDM,the intensity characteristic of the interference signal in the sensor is deduced.The characteristics of the double-ring sensing network connecting 9 sensors and its property of robust resisting destruction are verified by experiments,and the results are analyzed and discussed.
文摘Conference Theme-Anti-Crime Networking and Systems The 2007 IEEE International Conference on Networking,Sensing and Control will be held in London. The main theme of the conference is anti-crime networking and critical infrastructure.The area of anti- crime networking and critical infrastructure is a fusion of a number of research areas in networking, sensing,human factors,artificial intelligence,operational research,and systems control theory. However,the real challenge is to design anti-crime networking and systems from a holistic perspective; taking into account technical,organizational as well as contextual complexity.A system engineering approach is required to address new problems of this challenging and promising area.This conference will provide a remarkable opportunity for the academic and industrial community to address new challenges and share solutions,and discuss future research directions.It will feature plenary speeches, industrial panel sessions,funding agency panel sessions,interactive sessions,and invited/special sessions.Contributions are expected from academia,industry,EPSRC,EU,DTI,and MoD.Technical topics of the conference include but are not limited to:
基金supported in part by Sichuan Science and Technology Program (Nos. 2022NSFSC0912, 2020YJ0218,2021YFQ056 and 2022YFG0170)Fundamental Research Funds for the Central Universities (Nos. 2682021ZTPY051and 2682021CF019)+2 种基金NSFC (No. 62071393)NSFC High-Speed Rail Joint Foundation (No. U1834210)111 Project 111-2-14。
文摘Sensing in wireless local area network(WLAN) gains great interests recently. In this paper we focus on the multi-user WLAN sensing problem under the existing 802.11 standards. Multiple stations perform sensing with the access point and transmit channel state information(CSI)report simultaneously on the basis of uplink-orthogonal frequency division multiple access(OFDMA). Considering the transmission resource consumed in CSI report and the padding wastage in OFDMA based CSI report, we optimize the CSI simplification and uplink resource unit(RU)allocation jointly, aiming to balance the sensing accuracy and padding wastage performances in WLAN sensing. We propose the minimize padding maximize efficiency(MPME) algorithm to solve the problem and evaluate the performance of the proposed algorithm through extensive simulations.
基金All authors thank the National Engineering Laboratory for Fiber Optic Sensing Technology for offering the experimental equipment.This work was supported by the National Natural Science Foundation of China(Grant No.61290311)Hubei Key Laboratory of Radiation Chemistry and Functional Materials(Grant No.2019-20KZ08)State Key Laboratory of Advanced Technology for Materials Synthesis and Processing(Grant No.2019-KF-ll).
文摘Fiber Bragg grating(FBG)array,consisting of a number of sensing units in a single optical fiber,can be practically applied in quasi-distributed sensing networks.Serious signal crosstalk occurring between large-serial of identical FBGs,however,has limited the further increase in the number of sensing units,thus restricting applications only for short-distance sensing networks.To reduce the signal crosstalk,we design two novel types of 10-kilometer-long FBG arrays with 10000 equally spaced gratings,written on-line using a customized grating inscription system,which is affiliated to a drawing tower.Main factors causing signal crosstalk,such as spectral shadowing and multiple reflections,are firstly investigated in theory.Consistent with the theoretical findings,experimental results are proving that ultra-weak(the reflectivity of—40 dB)and multi-wavelength gratings of a number more than 10000 can be readily identified,with satisfied low crosstalk.The maximum attenuation of grating signal and minimum signal-to-noise ratio(SNR)in a single-wavelength array are 10.69 dB and 5.62 dB,respectively.As a comparison,by increasing the number of central wavelengths to three,the attenuation can be effectively reduced to 5.54dB and the minimum SNR has been improved to 8.14 dB.The current study significantly enhances the multiplexing capacity of FBG arrays and demonstrates promising potentials for establishing large-capacity quasi-distributed sensing networks.