Aimed at the problem of adaptive noise canceling(ANC),three implementary algorithms which are least mean square(LMS) algorithm,recursive least square(RLS) algorithm and fast affine projection(FAP) algorithm,have been ...Aimed at the problem of adaptive noise canceling(ANC),three implementary algorithms which are least mean square(LMS) algorithm,recursive least square(RLS) algorithm and fast affine projection(FAP) algorithm,have been researched.The simulations were made for the performance of these algorithms.The extraction of fetal electrocardiogram(FECG) is applied to compare the application effect of the above algorithms.The proposed FAP algorithm has obvious advantages in computational complexity,convergence speed and steadystate error.展开更多
An ultra-wide band (UWB) receiver front-end that operates at the UWB frequency range, starting from 9 GHz - 10.6 GHz is proposed in this paper. The proposed system consists of an off-chip microstrip antenna and CMOS d...An ultra-wide band (UWB) receiver front-end that operates at the UWB frequency range, starting from 9 GHz - 10.6 GHz is proposed in this paper. The proposed system consists of an off-chip microstrip antenna and CMOS differential low noise amplifier with a differential noise canceling (DNC) technique. The proposed antenna is trapezoidal dipole shaped with balun and printed on a low-cost FR4 substrate with dimensions 10 × 10 × 0.8 mm3. The balun circuit integrated with the ground antenna to improve the antenna impedance matching. Noise canceling is obtained by using a differential block with each stage having 2 amplifiers that generate differential signals, subtracted to improve total noise performance. The proposed DNC block improves NF by 50% while increasing total power consumption with only 0.1 Mw. The differential CMOS cascode LNA with DNC block is implemented using UMC 0.13 μm CMOS process, exhibits a flat gain of 19 dB, maximum noise figure of 2.75 dB, 1 dB compression point −16 dBm and 3rd order intercept point (IIP3) −10 dBm. The proposed system has total DC power consumption of 2.8 mW at 1.2 V power supply.展开更多
The analytic expression of the received echo in multilayers NDT (Non-Destruction Evaluation) is derived. Then based on the analytic solution, interface signals are analyzed; and it is concluded that the received u...The analytic expression of the received echo in multilayers NDT (Non-Destruction Evaluation) is derived. Then based on the analytic solution, interface signals are analyzed; and it is concluded that the received ultrasonic echo of mulilayers is composed of all the interface signals. By using the adaptive canceling of the signals from interfaces 0 and 1, the signals from interface 2 can be extracted. The method is applied to simulated and real echoes of multilayers,and the signals from interface 2 is separated successfully Based on the amplitude and arrival time of the signal from interface 2, the bond quality and depth of the interface can be evaluated展开更多
Conventional error cancellation approaches separate molecules into smaller fragments and sum the errors of all fragments to counteract the overall computational error of the parent molecules.However,these approaches m...Conventional error cancellation approaches separate molecules into smaller fragments and sum the errors of all fragments to counteract the overall computational error of the parent molecules.However,these approaches may be ineffective for systems with strong localized chemical effects,as fragmenting specific substructures into simpler chemical bonds can introduce additional errors instead of mitigating them.To address this issue,we propose the Substructure-Preserved Connection-Based Hierarchy(SCBH),a method that automatically identifies and freezes substructures with significant local chemical effects prior to molecular fragmentation.The SCBH is validated by the gas-phase enthalpy of formation calculation of CHNO molecules.Therein,based on the atomization scheme,the reference and test values are derived at the levels of Gaussian-4(G4)and M062X/6-31+G(2df,p),respectively.Compared to commonly used approaches,SCBH reduces the average computational error by half and requires only15%of the computational cost of G4 to achieve comparable accuracy.Since different types of local effect structures have differentiated influences on gas-phase enthalpy of formation,substituents with strong electronic effects should be retained preferentially.SCBH can be readily extended to diverse classes of organic compounds.Its workflow and source code allow flexible customization of molecular moieties,including azide,carboxyl,trinitromethyl,phenyl,and others.This strategy facilitates accurate,rapid,and automated computations and corrections,making it well-suited for high-throughput molecular screening and dataset construction for gas-phase enthalpy of formation.展开更多
In physics,our expectations for system behavior are often guided by intuitive arithmetic.For systems composed of identical units,we anticipate synergy of the contributions from these units,where 1+1=2.Conversely,for s...In physics,our expectations for system behavior are often guided by intuitive arithmetic.For systems composed of identical units,we anticipate synergy of the contributions from these units,where 1+1=2.Conversely,for systems built from opposing units,we expect cancellation of their contributions,where 1-1=0.This intuitive arithmetic has long underpinned our understanding of physical properties of materials,from electronic transport to optical responses.However,scientific breakthroughs often occur when nature reveals ways to circumvent these seemingly fundamental rules,opening new possibilities that challenge our deepest assumptions about material behavior.展开更多
This paper presents an inductorless complementary-noise-canceling LNA （CNCLNA） for TV tuners. The CNCLNA exploits single-to-differential topology, which consists of a common gate stage and a common source stage. The...This paper presents an inductorless complementary-noise-canceling LNA （CNCLNA） for TV tuners. The CNCLNA exploits single-to-differential topology, which consists of a common gate stage and a common source stage. The complementary topology can save power and improve the noise figure. Linearity is also enhanced by employing a multiple gated transistors technique. The chip is implemented in SMIC 0.18 μm CMOS technology. Measurement shows that the proposed CNCLNA achieves 13.5-16 dB voltage gain from 50 to 860 MHz, the noise figure is below 4.5 dB and has a minimum value of 2.9 dB, and the best PIdB is -7.5 dBm at 860 MHz. The core consumes 6 mA current with a supply voltage of 1.8 V, while the core area is only 0.2 ×0.2 mm2.展开更多
Guangxi has carried out the policy of differen- tiated power price earnestly.At the end of 2007,the price bureau of the autonomous re- gion has unveiled the policy of the cancellation of preferential electricity price...Guangxi has carried out the policy of differen- tiated power price earnestly.At the end of 2007,the price bureau of the autonomous re- gion has unveiled the policy of the cancellation of preferential electricity price for high energy consumption enterprises.展开更多
降噪耳机使用过度竞会导致大脑“听不清”?伦敦青年的经历引发健康警示!An alarming increase in hearing problems among young adults has been linked to Auditory Processing Disorder(APD,听觉处理障碍).Health experts warn that ...降噪耳机使用过度竞会导致大脑“听不清”?伦敦青年的经历引发健康警示!An alarming increase in hearing problems among young adults has been linked to Auditory Processing Disorder(APD,听觉处理障碍).Health experts warn that this issue could be partially associated with the growing use of noise-canceling headphones.展开更多
A new cyclic prefix(CP)-based nonoverlapping FBMC-QAM(CP-NO-FBMC-QAM)system with two prototype filters is proposed in this paper,which satisfies complex orthogonality conditions and good frequency energy confinement a...A new cyclic prefix(CP)-based nonoverlapping FBMC-QAM(CP-NO-FBMC-QAM)system with two prototype filters is proposed in this paper,which satisfies complex orthogonality conditions and good frequency energy confinement at the same time.We analyze its inter-carrier interference/inter-symbol interference(ICI/ISI)over multipath channels.Owing to the additional CP,the ISI of received symbols over multipath channels is eliminated in the proposed system,and the resulting improvement in the signal-to-interference ratio(SIR)performance is evaluated by theoretical analysis.Moreover,for the ICI caused by multipath propagation in received symbols,we develop a method that eliminates the ICI by frequency-domain channel estimation and equalization before the receiver filtering process.The proposed CP-NO-FBMC-QAM system and ICI cancellation method(ICICM)are validated by comparisons of implementation complexity,power spectral density(PSD),bit error rate(BER)and channel estimation performance with conventional CP-based orthogonal frequency division multiplexing(CP-OFDM)and FBMC-QAM systems.展开更多
In this paper,an interference cancellation based neural receiver for superimposed pilot(SIP)in multi-layer transmission is proposed,where the data and pilot are non-orthogonally superimposed in the same time-frequency...In this paper,an interference cancellation based neural receiver for superimposed pilot(SIP)in multi-layer transmission is proposed,where the data and pilot are non-orthogonally superimposed in the same time-frequency resource.Specifically,to deal with the intra-layer and inter-layer interference of SIP under multi-layer transmission,the interference cancellation with superimposed symbol aided channel estimation is leveraged in the neural receiver,accompanied by the pre-design of pilot code-division orthogonal mechanism at transmitter.In addition,to address the complexity issue for inter-vendor collaboration and the generalization problem in practical deployments,respectively,this paper also provides a fixed SIP(F-SIP)design based on constant pilot power ratio and scalable mechanisms for different modulation and coding schemes(MCSs)and transmission layers.Simulation results demonstrate the superiority of the proposed schemes on the performance of block error rate and throughput compared with existing counterparts.展开更多
To enable simultaneous transmit and receive(STAR)on the same frequency in a densely deployed space with multi-interference sources,this work proposes a digitally-assisted analog selfinterference cancellation method,wh...To enable simultaneous transmit and receive(STAR)on the same frequency in a densely deployed space with multi-interference sources,this work proposes a digitally-assisted analog selfinterference cancellation method,which can acquire reference signals through flexible wired/wireless switching access.Based on this method,the Minimum Mean Square Error algorithm with known channel state information is derived in detail,determining the upper limit of the cancellation performance,and the Adaptive Dithered Linear Search algorithm for real-time engineering cancellation is given.The correctness of theoretical analysis is verified by the practical self-interference channel measured by a vector network analyzer.Furthermore,we have designed and implemented the corresponding multiinterference cancellation prototype with the digitallyassisted structure,capable of handling multiple interferences(up to three)and supporting a large receive bandwidth of 100 MHz as well as a wide frequency coverage from 30 MHz to 3000 MHz.Prototype test results demonstrate that in the presence of three interferences,when the single interference bandwidth is 0.2/2/20 MHz(corresponding to the receive bandwidth of 2/20/100 MHz),the cancellation performance can reach 46/32/22 dB or more.展开更多
In wideband noncooperative interference cancellation,the reference signals obtained through auxiliary antennas are weighted to cancel with the interference signal.The correlation between the reference signal and the i...In wideband noncooperative interference cancellation,the reference signals obtained through auxiliary antennas are weighted to cancel with the interference signal.The correlation between the reference signal and the interference signal determines interference cancellation performance,while the auxiliary antenna array affects the correlation by influencing the amplitude and phase of the reference signals.This paper analyzes the effect of auxiliary antenna array on multiple performances of wideband noncooperative interference cancellation.Firstly,the array received signal model of wideband interference is established,and the weight vector coupled with the auxiliary antennas array manifold is solved by spectral analysis and eigen-subspace decomposition.Then,multiple performances which include cancellation resolution,grating null,wideband interference cancellation ratio(ICR),and convergence rate are quantitatively characterized with the auxiliary antenna array.It is obtained through analysis that the performances mutually restrict the auxiliary antenna array.Higher cancellation resolution requires larger array aperture,but when the number of auxiliary antennas is fixed,larger array aperture results in more grating nulls.When the auxiliary antennas are closer to the main antenna,the wideband ICR is improved,but the convergence rate is reduced.The conclusions are verified through simulation of one-dimensional uniform array and two-dimensional nonuniform array.The experiments of three arrays are compared,and the results conform well with simulation and support the theoretical analysis.展开更多
“civil discourse”amongst multiple individuals with diverse viewpoints is necessary to move toward truth,to maintain democratic buoyancy,and to get the most accurate read on how best to move forward toward our collec...“civil discourse”amongst multiple individuals with diverse viewpoints is necessary to move toward truth,to maintain democratic buoyancy,and to get the most accurate read on how best to move forward toward our collective good,civil discourse is nonetheless under catastrophic threat by contemporary forces that include the sloppy use of the term“hate speech”;the“libelling by labeling”(aka“cancelling”)in the public square of social media;technologically powered disinformation campaigns;and the growth of“safetyism”in academia.In light of these threats,the goal must be to convince educators,particularly philosophical educators,of the need to adopt a whole new focus in education,namely one that puts a spotlight on the fact that the utilization of the freedom of speech to destroy the freedom of speech of others utterly undermines the positive value of freedom of speech.In order to motivate individuals to turn their back on the dopamine rush of shutting someone down,educators must also spend a great deal of time showcasing the merits of“civil discourse”by providing young people with extensive experience in engaging in facilitated“civil discourse”(aka Communities of Philosophical Inquiry)so that its value can be woven into a personal commitment.展开更多
This work examines the impact of incorporating the physiological conditions of human cancellous bone,by integrating similar porosity of porous Fe with the cancellous bone under dynamic immersion test.All of the porous...This work examines the impact of incorporating the physiological conditions of human cancellous bone,by integrating similar porosity of porous Fe with the cancellous bone under dynamic immersion test.All of the porous Fe specimens with~80%porosity were immersed in Simulated Body Fluid(SBF)with a flow rate of 0.3 ml/min integrated with cancellous bone for 7,14 and 28 days.Porous Fe with the lowest surface area has the highest degradation rate despite having the lowest relative weight loss.The relationship between fluid induced shear stress and weight loss of specimens have been established.展开更多
The adaptive filtering algorithm with a fixed projection order is unable to adjust its performance in response to changes in the external environment of airborne radars.To overcome this limitation,a new approach is in...The adaptive filtering algorithm with a fixed projection order is unable to adjust its performance in response to changes in the external environment of airborne radars.To overcome this limitation,a new approach is introduced,which is the variable projection order Ekblom norm-promoted adaptive algorithm(VPO-EPAA).The method begins by examining the mean squared deviation(MSD)of the EPAA,deriving a formula for its MSD.Next,it compares the MSD of EPAA at two different projection orders and selects the one that minimizes the MSD as the parameter for the current iteration.Furthermore,the algorithm’s computational complexity is analyzed theoretically.Simulation results from system identification and self-interference cancellation show that the proposed algorithm performs exceptionally well in airborne radar signal self-interference cancellation,even under various noise intensities and types of interference.展开更多
Background:Telehealth has emerged as a powerful tool for managing chronic diseases and mental health conditions,offering increased access to care and improved patient outcomes.However,inequities in digital connectivit...Background:Telehealth has emerged as a powerful tool for managing chronic diseases and mental health conditions,offering increased access to care and improved patient outcomes.However,inequities in digital connectivity and technological resources have created significant disparities in access to these potentially life-changing services,disproportionately impacting marginalized and minoritized communities across the globe.Methods:Data on 473,716 telehealth encounters occurring between January 1,2022,and June 30,2023 were retrieved from the electronic health records(EHR)system used by University Hospitals.These encounters were classified into three groups:attended,canceled,and no-show.Relative risk was calculated based on age,sex,and race,and a multivariate linear regression was performed with age,sex,and race as inputs,to determine their effect on the encounter outcome.Results:Our analysis identified significant differences in relative risk between demographic groups.Patients 20-39 years of age had a high relative risk of cancellation and no-show,and Black patients demonstrated the highest relative risk for cancellation and no-show.The regression analysis illustrated a statistically significant link between no-shows and patients with a cellular plan with no other internet subscription(p<0.001),smartphone ownership(p<0.001),and not having a computer(p<0.05).Conclusions:This study highlights the clinical repercussions of the digital divide,as patients relying on a mobile phone and data plan to attend telehealth visits were more likely to no-show.Current disparities in digital connectivity for historically marginalized populations heightens the risk of creating a digital underclass.There is evidence this study may be applicable in multiple countries across the world.Further research on the causes of the observed no-shows is necessary to ensure equitable delivery of digital healthcare services.展开更多
This paper studies the sensing base station(SBS)that has great potential to improve the safety of vehicles and pedestrians on roads.SBS can detect the targets on the road with communication signals using the integrate...This paper studies the sensing base station(SBS)that has great potential to improve the safety of vehicles and pedestrians on roads.SBS can detect the targets on the road with communication signals using the integrated sensing and communication(ISAC)technique.Compared with vehicle-mounted radar,SBS has a better sensing field due to its higher deployment position,which can help solve the problem of sensing blind areas.In this paper,key technologies of SBS are studied,including the beamforming algorithm,beam scanning scheme,and interference cancellation algorithm.To transmit and receive ISAC signals simultaneously,a double-coupling antenna array is applied.The free detection beam and directional communication beam are proposed for joint communication and sensing to meet the requirements of beamwidth and pointing directions.The joint timespace-frequency domain division multiple access algorithm is proposed to cancel the interference of SBS,including multiuser interference and duplex interference between sensing and communication.Finally,the sensing and communication performance of SBS under the industrial scientific medical power limitation is analyzed and simulated.Simulation results show that the communication rate of SBS can reach over 100 Mbps and the range of sensing and communication can reach about 500 m.展开更多
To guarantee secure communication against eavesdropping and malicious attack,an artificial noise(AN)-aided frequency-hopping(FH)architecture is adopted in this article.But the inevitable time misalignment between the ...To guarantee secure communication against eavesdropping and malicious attack,an artificial noise(AN)-aided frequency-hopping(FH)architecture is adopted in this article.But the inevitable time misalignment between the received signal and locally reconstructed AN will deteriorate the AN cancellation performance,yielding significant secrecy degradation at the FH receiver.In view of this,first,the AN cancellation performance under time misalignment is evaluated via signal to AN-plus-noise ratio,and the system secrecy is analyzed via secrecy rate.Then,to mitigate the performance degradation raised by time misalignment,the transmitting power allocation scheme for AN and confidential signal(CS)is optimized,and the optimal hopping period is designed.Notably,the obtained conclusions in both the performance evaluation and transmitter optimization sections hold no matter whether the eavesdropper can realize FH synchronization or not.Simulations verify that time misalignment will raise non-negligible performance degradation.Besides,the power ratio of AN to CS should decrease as time misalignment increases,and for perfect time synchronization,the transmitting power of AN and CS should be equivalent.In addition,a longer hopping period is preferred for secrecy enhancement when time misalignment gets exacerbated.展开更多
This paper considers the short-range sensing imple-mentation in continuous-wave(CW)phased array systems.We specifically address this CW short-range sensing challenges stemming from the self-interference cancellation(S...This paper considers the short-range sensing imple-mentation in continuous-wave(CW)phased array systems.We specifically address this CW short-range sensing challenges stemming from the self-interference cancellation(SIC)operation and synthesis requirement of arbitrary beampatterns for the sensing purpose,which has rarely been researched before.In this paper,unlike the only existed work that exploits the heuris-tic method and shares no analytical solution,an SIC pattern syn-thesis design is presented with a closed-form solution.By utiliz-ing the null-space projection(NSP)method,the proposed method effectively mitigates the self-interference to enable the in-band full-duplex operation of the array system.Subsequently,the NSP design will be innovatively embedded in a singular value decomposition(SVD)based weighted alternating reserve projec-tion(WARP)approach to efficiently synthesize an arbitrary desired pattern by solving a unique rank-deficient weighted least mean square problem.Numerical results validate the effective-ness of the proposed method in terms of beampattern,SIC per-formance,and sensing performance.展开更多
Constituted by BCH component codes and its ordered statistics decoding(OSD),the successive cancellation list(SCL)decoding of U-UV structural codes can provide competent error-correction performance in the short-to-med...Constituted by BCH component codes and its ordered statistics decoding(OSD),the successive cancellation list(SCL)decoding of U-UV structural codes can provide competent error-correction performance in the short-to-medium length regime.However,this list decoding complexity becomes formidable as the decoding output list size increases.This is primarily incurred by the OSD.Addressing this challenge,this paper proposes the low complexity SCL decoding through reducing the complexity of component code decoding,and pruning the redundant SCL decoding paths.For the former,an efficient skipping rule is introduced for the OSD so that the higher order decoding can be skipped when they are not possible to provide a more likely codeword candidate.It is further extended to the OSD variant,the box-andmatch algorithm(BMA),in facilitating the component code decoding.Moreover,through estimating the correlation distance lower bounds(CDLBs)of the component code decoding outputs,a path pruning(PP)-SCL decoding is proposed to further facilitate the decoding of U-UV codes.In particular,its integration with the improved OSD and BMA is discussed.Simulation results show that significant complexity reduction can be achieved.Consequently,the U-UV codes can outperform the cyclic redundancy check(CRC)-polar codes with a similar decoding complexity.展开更多
基金the National Key Technologies R&D Program (No. 2006BAI22B01)
文摘Aimed at the problem of adaptive noise canceling(ANC),three implementary algorithms which are least mean square(LMS) algorithm,recursive least square(RLS) algorithm and fast affine projection(FAP) algorithm,have been researched.The simulations were made for the performance of these algorithms.The extraction of fetal electrocardiogram(FECG) is applied to compare the application effect of the above algorithms.The proposed FAP algorithm has obvious advantages in computational complexity,convergence speed and steadystate error.
文摘An ultra-wide band (UWB) receiver front-end that operates at the UWB frequency range, starting from 9 GHz - 10.6 GHz is proposed in this paper. The proposed system consists of an off-chip microstrip antenna and CMOS differential low noise amplifier with a differential noise canceling (DNC) technique. The proposed antenna is trapezoidal dipole shaped with balun and printed on a low-cost FR4 substrate with dimensions 10 × 10 × 0.8 mm3. The balun circuit integrated with the ground antenna to improve the antenna impedance matching. Noise canceling is obtained by using a differential block with each stage having 2 amplifiers that generate differential signals, subtracted to improve total noise performance. The proposed DNC block improves NF by 50% while increasing total power consumption with only 0.1 Mw. The differential CMOS cascode LNA with DNC block is implemented using UMC 0.13 μm CMOS process, exhibits a flat gain of 19 dB, maximum noise figure of 2.75 dB, 1 dB compression point −16 dBm and 3rd order intercept point (IIP3) −10 dBm. The proposed system has total DC power consumption of 2.8 mW at 1.2 V power supply.
文摘The analytic expression of the received echo in multilayers NDT (Non-Destruction Evaluation) is derived. Then based on the analytic solution, interface signals are analyzed; and it is concluded that the received ultrasonic echo of mulilayers is composed of all the interface signals. By using the adaptive canceling of the signals from interfaces 0 and 1, the signals from interface 2 can be extracted. The method is applied to simulated and real echoes of multilayers,and the signals from interface 2 is separated successfully Based on the amplitude and arrival time of the signal from interface 2, the bond quality and depth of the interface can be evaluated
基金the support of the National Natural Science Foundation of China(22575230)。
文摘Conventional error cancellation approaches separate molecules into smaller fragments and sum the errors of all fragments to counteract the overall computational error of the parent molecules.However,these approaches may be ineffective for systems with strong localized chemical effects,as fragmenting specific substructures into simpler chemical bonds can introduce additional errors instead of mitigating them.To address this issue,we propose the Substructure-Preserved Connection-Based Hierarchy(SCBH),a method that automatically identifies and freezes substructures with significant local chemical effects prior to molecular fragmentation.The SCBH is validated by the gas-phase enthalpy of formation calculation of CHNO molecules.Therein,based on the atomization scheme,the reference and test values are derived at the levels of Gaussian-4(G4)and M062X/6-31+G(2df,p),respectively.Compared to commonly used approaches,SCBH reduces the average computational error by half and requires only15%of the computational cost of G4 to achieve comparable accuracy.Since different types of local effect structures have differentiated influences on gas-phase enthalpy of formation,substituents with strong electronic effects should be retained preferentially.SCBH can be readily extended to diverse classes of organic compounds.Its workflow and source code allow flexible customization of molecular moieties,including azide,carboxyl,trinitromethyl,phenyl,and others.This strategy facilitates accurate,rapid,and automated computations and corrections,making it well-suited for high-throughput molecular screening and dataset construction for gas-phase enthalpy of formation.
基金supported by the National Natural Science Foundation of China (Grant No.12374109)the National Key Research and Development Program of China (Grant No.2023YFA1406600)。
文摘In physics,our expectations for system behavior are often guided by intuitive arithmetic.For systems composed of identical units,we anticipate synergy of the contributions from these units,where 1+1=2.Conversely,for systems built from opposing units,we expect cancellation of their contributions,where 1-1=0.This intuitive arithmetic has long underpinned our understanding of physical properties of materials,from electronic transport to optical responses.However,scientific breakthroughs often occur when nature reveals ways to circumvent these seemingly fundamental rules,opening new possibilities that challenge our deepest assumptions about material behavior.
基金Project supported by the Ministry of Industry and Information Technology,China(No.2009ZX03006-009)
文摘This paper presents an inductorless complementary-noise-canceling LNA （CNCLNA） for TV tuners. The CNCLNA exploits single-to-differential topology, which consists of a common gate stage and a common source stage. The complementary topology can save power and improve the noise figure. Linearity is also enhanced by employing a multiple gated transistors technique. The chip is implemented in SMIC 0.18 μm CMOS technology. Measurement shows that the proposed CNCLNA achieves 13.5-16 dB voltage gain from 50 to 860 MHz, the noise figure is below 4.5 dB and has a minimum value of 2.9 dB, and the best PIdB is -7.5 dBm at 860 MHz. The core consumes 6 mA current with a supply voltage of 1.8 V, while the core area is only 0.2 ×0.2 mm2.
文摘Guangxi has carried out the policy of differen- tiated power price earnestly.At the end of 2007,the price bureau of the autonomous re- gion has unveiled the policy of the cancellation of preferential electricity price for high energy consumption enterprises.
文摘降噪耳机使用过度竞会导致大脑“听不清”?伦敦青年的经历引发健康警示!An alarming increase in hearing problems among young adults has been linked to Auditory Processing Disorder(APD,听觉处理障碍).Health experts warn that this issue could be partially associated with the growing use of noise-canceling headphones.
文摘A new cyclic prefix(CP)-based nonoverlapping FBMC-QAM(CP-NO-FBMC-QAM)system with two prototype filters is proposed in this paper,which satisfies complex orthogonality conditions and good frequency energy confinement at the same time.We analyze its inter-carrier interference/inter-symbol interference(ICI/ISI)over multipath channels.Owing to the additional CP,the ISI of received symbols over multipath channels is eliminated in the proposed system,and the resulting improvement in the signal-to-interference ratio(SIR)performance is evaluated by theoretical analysis.Moreover,for the ICI caused by multipath propagation in received symbols,we develop a method that eliminates the ICI by frequency-domain channel estimation and equalization before the receiver filtering process.The proposed CP-NO-FBMC-QAM system and ICI cancellation method(ICICM)are validated by comparisons of implementation complexity,power spectral density(PSD),bit error rate(BER)and channel estimation performance with conventional CP-based orthogonal frequency division multiplexing(CP-OFDM)and FBMC-QAM systems.
文摘In this paper,an interference cancellation based neural receiver for superimposed pilot(SIP)in multi-layer transmission is proposed,where the data and pilot are non-orthogonally superimposed in the same time-frequency resource.Specifically,to deal with the intra-layer and inter-layer interference of SIP under multi-layer transmission,the interference cancellation with superimposed symbol aided channel estimation is leveraged in the neural receiver,accompanied by the pre-design of pilot code-division orthogonal mechanism at transmitter.In addition,to address the complexity issue for inter-vendor collaboration and the generalization problem in practical deployments,respectively,this paper also provides a fixed SIP(F-SIP)design based on constant pilot power ratio and scalable mechanisms for different modulation and coding schemes(MCSs)and transmission layers.Simulation results demonstrate the superiority of the proposed schemes on the performance of block error rate and throughput compared with existing counterparts.
基金supported in part by the National Natural Science Foundation of China under Grant 62071094in part by the National Key Laboratory of Wireless Communications Foundation under Grant IFN202402in part by the Postdoctoral Fellowship Program(Grade C)of China Postdoctoral Science Foundation under Grant GZC20240217.
文摘To enable simultaneous transmit and receive(STAR)on the same frequency in a densely deployed space with multi-interference sources,this work proposes a digitally-assisted analog selfinterference cancellation method,which can acquire reference signals through flexible wired/wireless switching access.Based on this method,the Minimum Mean Square Error algorithm with known channel state information is derived in detail,determining the upper limit of the cancellation performance,and the Adaptive Dithered Linear Search algorithm for real-time engineering cancellation is given.The correctness of theoretical analysis is verified by the practical self-interference channel measured by a vector network analyzer.Furthermore,we have designed and implemented the corresponding multiinterference cancellation prototype with the digitallyassisted structure,capable of handling multiple interferences(up to three)and supporting a large receive bandwidth of 100 MHz as well as a wide frequency coverage from 30 MHz to 3000 MHz.Prototype test results demonstrate that in the presence of three interferences,when the single interference bandwidth is 0.2/2/20 MHz(corresponding to the receive bandwidth of 2/20/100 MHz),the cancellation performance can reach 46/32/22 dB or more.
基金supported by the National Fund for Distinguished Young Scholars(52025072)the National Natural Science Foundation of China(52177012)the Foundation of National Key Laboratory of Science and Technology(614221722051301).
文摘In wideband noncooperative interference cancellation,the reference signals obtained through auxiliary antennas are weighted to cancel with the interference signal.The correlation between the reference signal and the interference signal determines interference cancellation performance,while the auxiliary antenna array affects the correlation by influencing the amplitude and phase of the reference signals.This paper analyzes the effect of auxiliary antenna array on multiple performances of wideband noncooperative interference cancellation.Firstly,the array received signal model of wideband interference is established,and the weight vector coupled with the auxiliary antennas array manifold is solved by spectral analysis and eigen-subspace decomposition.Then,multiple performances which include cancellation resolution,grating null,wideband interference cancellation ratio(ICR),and convergence rate are quantitatively characterized with the auxiliary antenna array.It is obtained through analysis that the performances mutually restrict the auxiliary antenna array.Higher cancellation resolution requires larger array aperture,but when the number of auxiliary antennas is fixed,larger array aperture results in more grating nulls.When the auxiliary antennas are closer to the main antenna,the wideband ICR is improved,but the convergence rate is reduced.The conclusions are verified through simulation of one-dimensional uniform array and two-dimensional nonuniform array.The experiments of three arrays are compared,and the results conform well with simulation and support the theoretical analysis.
文摘“civil discourse”amongst multiple individuals with diverse viewpoints is necessary to move toward truth,to maintain democratic buoyancy,and to get the most accurate read on how best to move forward toward our collective good,civil discourse is nonetheless under catastrophic threat by contemporary forces that include the sloppy use of the term“hate speech”;the“libelling by labeling”(aka“cancelling”)in the public square of social media;technologically powered disinformation campaigns;and the growth of“safetyism”in academia.In light of these threats,the goal must be to convince educators,particularly philosophical educators,of the need to adopt a whole new focus in education,namely one that puts a spotlight on the fact that the utilization of the freedom of speech to destroy the freedom of speech of others utterly undermines the positive value of freedom of speech.In order to motivate individuals to turn their back on the dopamine rush of shutting someone down,educators must also spend a great deal of time showcasing the merits of“civil discourse”by providing young people with extensive experience in engaging in facilitated“civil discourse”(aka Communities of Philosophical Inquiry)so that its value can be woven into a personal commitment.
基金funded by the Ministry of Higher Education,Malaysia under the Fundamental Research Grant Scheme(FRGS/1/2018/TK03/UTM/02/8).
文摘This work examines the impact of incorporating the physiological conditions of human cancellous bone,by integrating similar porosity of porous Fe with the cancellous bone under dynamic immersion test.All of the porous Fe specimens with~80%porosity were immersed in Simulated Body Fluid(SBF)with a flow rate of 0.3 ml/min integrated with cancellous bone for 7,14 and 28 days.Porous Fe with the lowest surface area has the highest degradation rate despite having the lowest relative weight loss.The relationship between fluid induced shear stress and weight loss of specimens have been established.
基金supported by the Shan⁃dong Provincial Natural Science Foundation(No.ZR2022MF314).
文摘The adaptive filtering algorithm with a fixed projection order is unable to adjust its performance in response to changes in the external environment of airborne radars.To overcome this limitation,a new approach is introduced,which is the variable projection order Ekblom norm-promoted adaptive algorithm(VPO-EPAA).The method begins by examining the mean squared deviation(MSD)of the EPAA,deriving a formula for its MSD.Next,it compares the MSD of EPAA at two different projection orders and selects the one that minimizes the MSD as the parameter for the current iteration.Furthermore,the algorithm’s computational complexity is analyzed theoretically.Simulation results from system identification and self-interference cancellation show that the proposed algorithm performs exceptionally well in airborne radar signal self-interference cancellation,even under various noise intensities and types of interference.
文摘Background:Telehealth has emerged as a powerful tool for managing chronic diseases and mental health conditions,offering increased access to care and improved patient outcomes.However,inequities in digital connectivity and technological resources have created significant disparities in access to these potentially life-changing services,disproportionately impacting marginalized and minoritized communities across the globe.Methods:Data on 473,716 telehealth encounters occurring between January 1,2022,and June 30,2023 were retrieved from the electronic health records(EHR)system used by University Hospitals.These encounters were classified into three groups:attended,canceled,and no-show.Relative risk was calculated based on age,sex,and race,and a multivariate linear regression was performed with age,sex,and race as inputs,to determine their effect on the encounter outcome.Results:Our analysis identified significant differences in relative risk between demographic groups.Patients 20-39 years of age had a high relative risk of cancellation and no-show,and Black patients demonstrated the highest relative risk for cancellation and no-show.The regression analysis illustrated a statistically significant link between no-shows and patients with a cellular plan with no other internet subscription(p<0.001),smartphone ownership(p<0.001),and not having a computer(p<0.05).Conclusions:This study highlights the clinical repercussions of the digital divide,as patients relying on a mobile phone and data plan to attend telehealth visits were more likely to no-show.Current disparities in digital connectivity for historically marginalized populations heightens the risk of creating a digital underclass.There is evidence this study may be applicable in multiple countries across the world.Further research on the causes of the observed no-shows is necessary to ensure equitable delivery of digital healthcare services.
基金supported in part by the National Natural Science Foundation of China under Grant U21B2014,Grant 92267202,and Grant 62271081.
文摘This paper studies the sensing base station(SBS)that has great potential to improve the safety of vehicles and pedestrians on roads.SBS can detect the targets on the road with communication signals using the integrated sensing and communication(ISAC)technique.Compared with vehicle-mounted radar,SBS has a better sensing field due to its higher deployment position,which can help solve the problem of sensing blind areas.In this paper,key technologies of SBS are studied,including the beamforming algorithm,beam scanning scheme,and interference cancellation algorithm.To transmit and receive ISAC signals simultaneously,a double-coupling antenna array is applied.The free detection beam and directional communication beam are proposed for joint communication and sensing to meet the requirements of beamwidth and pointing directions.The joint timespace-frequency domain division multiple access algorithm is proposed to cancel the interference of SBS,including multiuser interference and duplex interference between sensing and communication.Finally,the sensing and communication performance of SBS under the industrial scientific medical power limitation is analyzed and simulated.Simulation results show that the communication rate of SBS can reach over 100 Mbps and the range of sensing and communication can reach about 500 m.
基金supported in part by the National Natural Science Foundation of China under Grant 62071094in part by the National Key Laboratory of Wireless Communications Foundation under Grant IFN202402in part by the Postdoctoral Fellowship Program(Grade C)of China Postdoctoral Science Foundation under Grant GZC20240217.
文摘To guarantee secure communication against eavesdropping and malicious attack,an artificial noise(AN)-aided frequency-hopping(FH)architecture is adopted in this article.But the inevitable time misalignment between the received signal and locally reconstructed AN will deteriorate the AN cancellation performance,yielding significant secrecy degradation at the FH receiver.In view of this,first,the AN cancellation performance under time misalignment is evaluated via signal to AN-plus-noise ratio,and the system secrecy is analyzed via secrecy rate.Then,to mitigate the performance degradation raised by time misalignment,the transmitting power allocation scheme for AN and confidential signal(CS)is optimized,and the optimal hopping period is designed.Notably,the obtained conclusions in both the performance evaluation and transmitter optimization sections hold no matter whether the eavesdropper can realize FH synchronization or not.Simulations verify that time misalignment will raise non-negligible performance degradation.Besides,the power ratio of AN to CS should decrease as time misalignment increases,and for perfect time synchronization,the transmitting power of AN and CS should be equivalent.In addition,a longer hopping period is preferred for secrecy enhancement when time misalignment gets exacerbated.
基金supported by the National Natural Science Foundation of China(62001227)the Academy of Finland(315858341489).
文摘This paper considers the short-range sensing imple-mentation in continuous-wave(CW)phased array systems.We specifically address this CW short-range sensing challenges stemming from the self-interference cancellation(SIC)operation and synthesis requirement of arbitrary beampatterns for the sensing purpose,which has rarely been researched before.In this paper,unlike the only existed work that exploits the heuris-tic method and shares no analytical solution,an SIC pattern syn-thesis design is presented with a closed-form solution.By utiliz-ing the null-space projection(NSP)method,the proposed method effectively mitigates the self-interference to enable the in-band full-duplex operation of the array system.Subsequently,the NSP design will be innovatively embedded in a singular value decomposition(SVD)based weighted alternating reserve projec-tion(WARP)approach to efficiently synthesize an arbitrary desired pattern by solving a unique rank-deficient weighted least mean square problem.Numerical results validate the effective-ness of the proposed method in terms of beampattern,SIC per-formance,and sensing performance.
基金supported by the National Natural Science Foundation of China(NSFC)with project ID 62071498the Guangdong National Science Foundation(GDNSF)with project ID 2024A1515010213.
文摘Constituted by BCH component codes and its ordered statistics decoding(OSD),the successive cancellation list(SCL)decoding of U-UV structural codes can provide competent error-correction performance in the short-to-medium length regime.However,this list decoding complexity becomes formidable as the decoding output list size increases.This is primarily incurred by the OSD.Addressing this challenge,this paper proposes the low complexity SCL decoding through reducing the complexity of component code decoding,and pruning the redundant SCL decoding paths.For the former,an efficient skipping rule is introduced for the OSD so that the higher order decoding can be skipped when they are not possible to provide a more likely codeword candidate.It is further extended to the OSD variant,the box-andmatch algorithm(BMA),in facilitating the component code decoding.Moreover,through estimating the correlation distance lower bounds(CDLBs)of the component code decoding outputs,a path pruning(PP)-SCL decoding is proposed to further facilitate the decoding of U-UV codes.In particular,its integration with the improved OSD and BMA is discussed.Simulation results show that significant complexity reduction can be achieved.Consequently,the U-UV codes can outperform the cyclic redundancy check(CRC)-polar codes with a similar decoding complexity.
