With the gradual popularization of 5G communications,the application of multi-antenna broadcasting technology has become widespread.Therefore,this study aims to investigate the wireless covert communication in the two...With the gradual popularization of 5G communications,the application of multi-antenna broadcasting technology has become widespread.Therefore,this study aims to investigate the wireless covert communication in the two-user cooperative multi-antenna broadcast channel.We focus on the issue that the deteriorated reliability and undetectability are mainly affected by the transmission power.To tackle this issue,we design a scheme based on beamforming to increase the reliability and undetectability of wireless covert communication in the multi-antenna broadcast channel.We first modeled and analyzed the cooperative multi-antenna broadcasting system,and put forward the target question.Then we use the SCA(successive convex approximation)algorithm to transform the target problem into a series of convex subproblems.Then the convex problems are solved and the covert channel capacity is calculated.In order to verify the effectiveness of the scheme,we conducted simulation verification.The simulation results show that the proposed beamforming scheme can effectively improve the reliability and undetectability of covert communication in multi-antenna broadcast channels.展开更多
We consider an image semantic communication system in a time-varying fading Gaussian MIMO channel,with a finite number of channel states.A deep learning-aided broadcast approach scheme is proposed to benefit the adapt...We consider an image semantic communication system in a time-varying fading Gaussian MIMO channel,with a finite number of channel states.A deep learning-aided broadcast approach scheme is proposed to benefit the adaptive semantic transmission in terms of different channel states.We combine the classic broadcast approach with the image transformer to implement this adaptive joint source and channel coding(JSCC)scheme.Specifically,we utilize the neural network(NN)to jointly optimize the hierarchical image compression and superposition code mapping within this scheme.The learned transformers and codebooks allow recovering of the image with an adaptive quality and low error rate at the receiver side,in each channel state.The simulation results exhibit our proposed scheme can dynamically adapt the coding to the current channel state and outperform some existing intelligent schemes with the fixed coding block.展开更多
Channel equalization plays a pivotal role within the reconstruction phase of passive radar reference signals.In the context of reconstructing digital terrestrial multimedia broadcasting(DTMB)signals for low-slow-small...Channel equalization plays a pivotal role within the reconstruction phase of passive radar reference signals.In the context of reconstructing digital terrestrial multimedia broadcasting(DTMB)signals for low-slow-small(LSS)target detection,a novel frequency domain block joint equalization algorithm is presented in this article.From the DTMB signal frame structure and channel multipath transmission characteristics,this article adopts a unconventional approach where the delay and frame structure of each DTMB signal frame are reconfigured to create a circular convolution block,facilitating concurrent fast Fourier transform(FFT)calculations.Following equalization,an inverse fast Fourier transform(IFFT)-based joint output and subsequent data reordering are executed to finalize the equalization process for the DTMB signal.Simulation and measured data confirm that this algorithm outperforms conventional techniques by reducing signal errors rate and enhancing real-time processing.In passive radar LSS detection,it effectively suppresses multipath and noise through frequency domain equalization,reducing false alarms and improving the capabilities of weak target detection.展开更多
Broadcasting gateway equipment generally uses a method of simply switching to a spare input stream when a failure occurs in a main input stream.However,when the transmission environment is unstable,problems such as re...Broadcasting gateway equipment generally uses a method of simply switching to a spare input stream when a failure occurs in a main input stream.However,when the transmission environment is unstable,problems such as reduction in the lifespan of equipment due to frequent switching and interruption,delay,and stoppage of services may occur.Therefore,applying a machine learning(ML)method,which is possible to automatically judge and classify network-related service anomaly,and switch multi-input signals without dropping or changing signals by predicting or quickly determining the time of error occurrence for smooth stream switching when there are problems such as transmission errors,is required.In this paper,we propose an intelligent packet switching method based on the ML method of classification,which is one of the supervised learning methods,that presents the risk level of abnormal multi-stream occurring in broadcasting gateway equipment based on data.Furthermore,we subdivide the risk levels obtained from classification techniques into probabilities and then derive vectorized representative values for each attribute value of the collected input data and continuously update them.The obtained reference vector value is used for switching judgment through the cosine similarity value between input data obtained when a dangerous situation occurs.In the broadcasting gateway equipment to which the proposed method is applied,it is possible to perform more stable and smarter switching than before by solving problems of reliability and broadcasting accidents of the equipment and can maintain stable video streaming as well.展开更多
China’s broadcasters enter the final phase of preparations fbr next year’s Olympic Games The most critical information we are keen on delivering is that every- thing is going well,said Sun Weijia, Director of the Me...China’s broadcasters enter the final phase of preparations fbr next year’s Olympic Games The most critical information we are keen on delivering is that every- thing is going well,said Sun Weijia, Director of the Media Operations Department of the Beijing Organizing Committee for the Games of of the XXIX Olympiad(BOCOG)on the eve of the 2007 World Broadcasters Conference.展开更多
This study investigates artificial noise aided Multiuser Multiple-Input Single-Output(MU-MISO)broadcast wiretap system designs in slow fading channel environment.We adopt a beamforming technique with artificial noise ...This study investigates artificial noise aided Multiuser Multiple-Input Single-Output(MU-MISO)broadcast wiretap system designs in slow fading channel environment.We adopt a beamforming technique with artificial noise to achieve secure multiuser communication and optimize system performance.To overcome the complexity of this model,a novel optimization scheme using semiclosed-form expressions and Monte Carlo method is employed to derive the relationship between transmission parameters and secure transmission performance.In this article,we detail the procedure of our new method,and conduct some heuristic simulation works.The simulation results reveal how power allocation ratio and information rate influence the multiuser system secure transmission probability and effective secrecy throughput of the multiuser system.We compare the multiuser system security and throughput performance with each user’s performance,which helps us to verify the security ability of our method.Our research results extend the traditional single-user artificial noise design method to multiuser scenarios,and provide ideas for solving the optimization problem of multi-user broadcast communication.展开更多
Broadcast gymnastics,which was initiated in 1951,is one of the most widely adopted and popular mass sports activities in China,embodying the country's commitment to shaping the right to health of its citizens.The ...Broadcast gymnastics,which was initiated in 1951,is one of the most widely adopted and popular mass sports activities in China,embodying the country's commitment to shaping the right to health of its citizens.The history and development of broadcast gymnastics are closely tied to the destiny of the nation,reflecting clear national will,and aiming to achieve the goal of“shaping new individuals”.The institutional forms of broadcast gymnastics can be categorized into three stages:“military simulation”,“administrative reinforcement”and“market competition”,each of which aligns with the objectives and needs of different periods.Taking the establishment and promotion of broadcast gymnastics in China as a focal point helps construct a doctrinal framework for the right to health.Based on the purposes and means of health shaping,the implementation of the right to health can be divided into four types:national health projects,citizens'health rights,the social health industry,and civic health consumption.National health projects,facilitated by legislative mechanisms,provide institutional support and supply for citizens'health rights.The right to health,as a social right,has both a subjective rights orientation and an objective value order orientation,thus establishing the individual's subject status in terms of their right to health.Its defense aspect is oriented toward rejecting excessive state intervention,while the benefit aspect directly links to the state's payment measures.The boundaries of state power also need to be defined in the social health industry and civic health consumption.Hence,developing broadcast gymnastics involves adjusting its relationship with the overall objectives of the state and individual citizens'needs.It involves balancing the use of administrative and market methods,continually innovating sports programs that better suit diverse needs,and actively participating in the competition of the fitness market.展开更多
Traditional Production Techniques of Xuan Paper Chief Director:Hai Jinxing Length:Three Episodes Sponsor:Department of Intangible Cultural Heritage of Ministry of Culture and Tourism Broadcasting Platform:Bilibili In ...Traditional Production Techniques of Xuan Paper Chief Director:Hai Jinxing Length:Three Episodes Sponsor:Department of Intangible Cultural Heritage of Ministry of Culture and Tourism Broadcasting Platform:Bilibili In 2009,the traditional handicraft of making Xuan paper was inscribed on the Representative List of Intangible Cultural Heritage of Humanity by UNESCO.展开更多
It was on the evening of Oct.24th,2023.Even though I had known the result,I still felt very nervous,sitting in front of TV and watching Women’s 100m T11 Finals at the Asian Para Games,as if it was live broadcasting.T...It was on the evening of Oct.24th,2023.Even though I had known the result,I still felt very nervous,sitting in front of TV and watching Women’s 100m T11 Finals at the Asian Para Games,as if it was live broadcasting.The moment the starting gun fired,Chinese visually impaired athlete and gold medalist,Liu Cuiqing,sprinted right away.展开更多
2014年7月28日美国国会众议院通过《美国国际广播改革法案》（U.S. International Broadcasting Reform Bill,H.R.4490）,标志着美国国内针对美国广播理事会（Broadcasting Board of Governors,BBG）的改革拉开了序幕。近些年,美国国内...2014年7月28日美国国会众议院通过《美国国际广播改革法案》（U.S. International Broadcasting Reform Bill,H.R.4490）,标志着美国国内针对美国广播理事会（Broadcasting Board of Governors,BBG）的改革拉开了序幕。近些年,美国国内对BBG进行改革的呼声日益强烈,其主要原因是美国国际广播的传播影响力受到质疑。展开更多
基金supported by the National Natural Science Foundation of China(Grants No.U1836104,61772281,61702235,61801073,61931004,62072250).
文摘With the gradual popularization of 5G communications,the application of multi-antenna broadcasting technology has become widespread.Therefore,this study aims to investigate the wireless covert communication in the two-user cooperative multi-antenna broadcast channel.We focus on the issue that the deteriorated reliability and undetectability are mainly affected by the transmission power.To tackle this issue,we design a scheme based on beamforming to increase the reliability and undetectability of wireless covert communication in the multi-antenna broadcast channel.We first modeled and analyzed the cooperative multi-antenna broadcasting system,and put forward the target question.Then we use the SCA(successive convex approximation)algorithm to transform the target problem into a series of convex subproblems.Then the convex problems are solved and the covert channel capacity is calculated.In order to verify the effectiveness of the scheme,we conducted simulation verification.The simulation results show that the proposed beamforming scheme can effectively improve the reliability and undetectability of covert communication in multi-antenna broadcast channels.
基金supported in part by the National Key R&D Project of China under Grant 2020YFA0712300National Natural Science Foundation of China under Grant NSFC-62231022,12031011supported in part by the NSF of China under Grant 62125108。
文摘We consider an image semantic communication system in a time-varying fading Gaussian MIMO channel,with a finite number of channel states.A deep learning-aided broadcast approach scheme is proposed to benefit the adaptive semantic transmission in terms of different channel states.We combine the classic broadcast approach with the image transformer to implement this adaptive joint source and channel coding(JSCC)scheme.Specifically,we utilize the neural network(NN)to jointly optimize the hierarchical image compression and superposition code mapping within this scheme.The learned transformers and codebooks allow recovering of the image with an adaptive quality and low error rate at the receiver side,in each channel state.The simulation results exhibit our proposed scheme can dynamically adapt the coding to the current channel state and outperform some existing intelligent schemes with the fixed coding block.
文摘Channel equalization plays a pivotal role within the reconstruction phase of passive radar reference signals.In the context of reconstructing digital terrestrial multimedia broadcasting(DTMB)signals for low-slow-small(LSS)target detection,a novel frequency domain block joint equalization algorithm is presented in this article.From the DTMB signal frame structure and channel multipath transmission characteristics,this article adopts a unconventional approach where the delay and frame structure of each DTMB signal frame are reconfigured to create a circular convolution block,facilitating concurrent fast Fourier transform(FFT)calculations.Following equalization,an inverse fast Fourier transform(IFFT)-based joint output and subsequent data reordering are executed to finalize the equalization process for the DTMB signal.Simulation and measured data confirm that this algorithm outperforms conventional techniques by reducing signal errors rate and enhancing real-time processing.In passive radar LSS detection,it effectively suppresses multipath and noise through frequency domain equalization,reducing false alarms and improving the capabilities of weak target detection.
基金This work was supported by a research grant from Seoul Women’s University(2023-0183).
文摘Broadcasting gateway equipment generally uses a method of simply switching to a spare input stream when a failure occurs in a main input stream.However,when the transmission environment is unstable,problems such as reduction in the lifespan of equipment due to frequent switching and interruption,delay,and stoppage of services may occur.Therefore,applying a machine learning(ML)method,which is possible to automatically judge and classify network-related service anomaly,and switch multi-input signals without dropping or changing signals by predicting or quickly determining the time of error occurrence for smooth stream switching when there are problems such as transmission errors,is required.In this paper,we propose an intelligent packet switching method based on the ML method of classification,which is one of the supervised learning methods,that presents the risk level of abnormal multi-stream occurring in broadcasting gateway equipment based on data.Furthermore,we subdivide the risk levels obtained from classification techniques into probabilities and then derive vectorized representative values for each attribute value of the collected input data and continuously update them.The obtained reference vector value is used for switching judgment through the cosine similarity value between input data obtained when a dangerous situation occurs.In the broadcasting gateway equipment to which the proposed method is applied,it is possible to perform more stable and smarter switching than before by solving problems of reliability and broadcasting accidents of the equipment and can maintain stable video streaming as well.
文摘China’s broadcasters enter the final phase of preparations fbr next year’s Olympic Games The most critical information we are keen on delivering is that every- thing is going well,said Sun Weijia, Director of the Media Operations Department of the Beijing Organizing Committee for the Games of of the XXIX Olympiad(BOCOG)on the eve of the 2007 World Broadcasters Conference.
基金National Natural Science Foundation of China(61601425)。
文摘This study investigates artificial noise aided Multiuser Multiple-Input Single-Output(MU-MISO)broadcast wiretap system designs in slow fading channel environment.We adopt a beamforming technique with artificial noise to achieve secure multiuser communication and optimize system performance.To overcome the complexity of this model,a novel optimization scheme using semiclosed-form expressions and Monte Carlo method is employed to derive the relationship between transmission parameters and secure transmission performance.In this article,we detail the procedure of our new method,and conduct some heuristic simulation works.The simulation results reveal how power allocation ratio and information rate influence the multiuser system secure transmission probability and effective secrecy throughput of the multiuser system.We compare the multiuser system security and throughput performance with each user’s performance,which helps us to verify the security ability of our method.Our research results extend the traditional single-user artificial noise design method to multiuser scenarios,and provide ideas for solving the optimization problem of multi-user broadcast communication.
基金the stage achievement of the National Social Science Foundation’s key project“Research on the New Forms of Human Rights Civilization in China”(Project No.21AZD095)the major project“Research on General Secretary Xi Jinping’s Important Expositions on Human Rights”(Project No.20JJD820002)of the Ministry of Education of the People’s Republic of China。
文摘Broadcast gymnastics,which was initiated in 1951,is one of the most widely adopted and popular mass sports activities in China,embodying the country's commitment to shaping the right to health of its citizens.The history and development of broadcast gymnastics are closely tied to the destiny of the nation,reflecting clear national will,and aiming to achieve the goal of“shaping new individuals”.The institutional forms of broadcast gymnastics can be categorized into three stages:“military simulation”,“administrative reinforcement”and“market competition”,each of which aligns with the objectives and needs of different periods.Taking the establishment and promotion of broadcast gymnastics in China as a focal point helps construct a doctrinal framework for the right to health.Based on the purposes and means of health shaping,the implementation of the right to health can be divided into four types:national health projects,citizens'health rights,the social health industry,and civic health consumption.National health projects,facilitated by legislative mechanisms,provide institutional support and supply for citizens'health rights.The right to health,as a social right,has both a subjective rights orientation and an objective value order orientation,thus establishing the individual's subject status in terms of their right to health.Its defense aspect is oriented toward rejecting excessive state intervention,while the benefit aspect directly links to the state's payment measures.The boundaries of state power also need to be defined in the social health industry and civic health consumption.Hence,developing broadcast gymnastics involves adjusting its relationship with the overall objectives of the state and individual citizens'needs.It involves balancing the use of administrative and market methods,continually innovating sports programs that better suit diverse needs,and actively participating in the competition of the fitness market.
文摘Traditional Production Techniques of Xuan Paper Chief Director:Hai Jinxing Length:Three Episodes Sponsor:Department of Intangible Cultural Heritage of Ministry of Culture and Tourism Broadcasting Platform:Bilibili In 2009,the traditional handicraft of making Xuan paper was inscribed on the Representative List of Intangible Cultural Heritage of Humanity by UNESCO.
文摘It was on the evening of Oct.24th,2023.Even though I had known the result,I still felt very nervous,sitting in front of TV and watching Women’s 100m T11 Finals at the Asian Para Games,as if it was live broadcasting.The moment the starting gun fired,Chinese visually impaired athlete and gold medalist,Liu Cuiqing,sprinted right away.
文摘2014年7月28日美国国会众议院通过《美国国际广播改革法案》（U.S. International Broadcasting Reform Bill,H.R.4490）,标志着美国国内针对美国广播理事会（Broadcasting Board of Governors,BBG）的改革拉开了序幕。近些年,美国国内对BBG进行改革的呼声日益强烈,其主要原因是美国国际广播的传播影响力受到质疑。
