There is an increasing demand for supporting high-quality real-time audiovisual services for the next generation wired and wireless networks. However, due to variety of bandwidths of different networks, it is a great ...There is an increasing demand for supporting high-quality real-time audiovisual services for the next generation wired and wireless networks. However, due to variety of bandwidths of different networks, it is a great challenge for deployment. In this paper, a novel high-definition (HD) video transmission system was proposed which depends upon reliable compound multicast protocols and QoS control over the various kinds of networks. This system detects client's network condition and assigns it to a proper proxy. Each proxy is capable of detecting network parameters and adaptively tuning such transport parameters as bit rate, video resolution, frame rate and QoS mechanisms to this condition. It also provides FEC error recovery under consideration of characteristics of MPEG4 video codec. Our simulation demonstrates that different network clients such as ADSL, CERNET, and CERNET2 can receive more video reliability with less delay.展开更多
Visible Light Communication( VLC) based on LED is a new wireless communication technology with high response rate and good modulation characteristics in the wavelengths of 380- 780 nm. Compared with conventional metho...Visible Light Communication( VLC) based on LED is a new wireless communication technology with high response rate and good modulation characteristics in the wavelengths of 380- 780 nm. Compared with conventional methods,the waveband of VLC is harmless to human and safe to communication because of no magnetism radiation. An audio information transmission system using LED traffic lights is presented based on VLC technology. The system is consisted of transmitting terminal,receiving terminal and communication channel. Some experiments were made under real communication environment. The experimental results showed that the traffic information transmission system works steadily with good communication quality and achieves the purpose of transmitting audio information through LED traffic lights,with a data transfer rate up to 250 kbps over a distance of 5 meters.展开更多
光纤共享模式利用多重数字音频接口(Multi-channel Audio Digital Interface,MADI)技术,有效管理和传输广播电视音频信号。详细讨论该模式的系统设计,包括主备混音设备配置、光纤分配切换单元功能以及远程与本地共享机箱的应用。通过具...光纤共享模式利用多重数字音频接口(Multi-channel Audio Digital Interface,MADI)技术,有效管理和传输广播电视音频信号。详细讨论该模式的系统设计,包括主备混音设备配置、光纤分配切换单元功能以及远程与本地共享机箱的应用。通过具体案例分析该技术在广播中的实际应用,展示其在提升音质、降低成本和增强系统可靠性方面的显著效益。结果表明,光纤共享模式显著优化了音频处理流程,降低了维护成本,提高了广播系统的整体效率和稳定性。展开更多
文摘There is an increasing demand for supporting high-quality real-time audiovisual services for the next generation wired and wireless networks. However, due to variety of bandwidths of different networks, it is a great challenge for deployment. In this paper, a novel high-definition (HD) video transmission system was proposed which depends upon reliable compound multicast protocols and QoS control over the various kinds of networks. This system detects client's network condition and assigns it to a proper proxy. Each proxy is capable of detecting network parameters and adaptively tuning such transport parameters as bit rate, video resolution, frame rate and QoS mechanisms to this condition. It also provides FEC error recovery under consideration of characteristics of MPEG4 video codec. Our simulation demonstrates that different network clients such as ADSL, CERNET, and CERNET2 can receive more video reliability with less delay.
基金Sponsored by the National Science and Technology Innovation Fund for Small and Medium Enterprises(Grant No.10C26211200144)Tianjin Science and Technology Key Supporting Projects(Grant No.10ZCGYGX18300)
文摘Visible Light Communication( VLC) based on LED is a new wireless communication technology with high response rate and good modulation characteristics in the wavelengths of 380- 780 nm. Compared with conventional methods,the waveband of VLC is harmless to human and safe to communication because of no magnetism radiation. An audio information transmission system using LED traffic lights is presented based on VLC technology. The system is consisted of transmitting terminal,receiving terminal and communication channel. Some experiments were made under real communication environment. The experimental results showed that the traffic information transmission system works steadily with good communication quality and achieves the purpose of transmitting audio information through LED traffic lights,with a data transfer rate up to 250 kbps over a distance of 5 meters.
文摘光纤共享模式利用多重数字音频接口(Multi-channel Audio Digital Interface,MADI)技术,有效管理和传输广播电视音频信号。详细讨论该模式的系统设计,包括主备混音设备配置、光纤分配切换单元功能以及远程与本地共享机箱的应用。通过具体案例分析该技术在广播中的实际应用,展示其在提升音质、降低成本和增强系统可靠性方面的显著效益。结果表明,光纤共享模式显著优化了音频处理流程,降低了维护成本,提高了广播系统的整体效率和稳定性。
