以5G为代表的未来移动接入网将采用集中式的云化网络架构,即基带处理单元(baseband unit,BBU)部署在中心机房,而远端射频单元(remote radio head,RRH)只保留射频处理功能或部分基带处理功能,二者的通信由前传链路承载.目前,以基于以太...以5G为代表的未来移动接入网将采用集中式的云化网络架构,即基带处理单元(baseband unit,BBU)部署在中心机房,而远端射频单元(remote radio head,RRH)只保留射频处理功能或部分基带处理功能,二者的通信由前传链路承载.目前,以基于以太的通用公共射频接口(Ethernet common public radio interface,eCPRI)为代表的采用移动通信物理层功能单元解耦的前传接口逐渐成为业界的一大主流,随之带来的问题是在这种接口划分下,前传接口数据量会随着移动业务量的变化而波动.为了保证高负载时期的链路传输质量,部署的链路容量往往参考链路峰值速率,这导致链路的利用率整体较低.针对此问题,本文提出了一种弹性量化精度的方案,在高负载状态采用低量化位数来降低前传接口链路的峰值速率,从而节省链路资源的部署.该方案通过仿真与实验进行了验证,结果显示此方案可以大约节省38%的链路资源.展开更多
In Bangladesh, more than a dozen of private TV channels are operating and about 10 new channels are waiting with green signal for transmission. Bangladesh Television （BTV）, the only government owned and administered...In Bangladesh, more than a dozen of private TV channels are operating and about 10 new channels are waiting with green signal for transmission. Bangladesh Television （BTV）, the only government owned and administered, and known as structurally a biased institution serves the audience the public service information most. At the same time it serves purposes of incumbent government. Public information （PI） broadcast means broadcasting towards public welfare which may bring about change in the betterment of life and work of people. Its main focus would be on information, education, and motivation values rather than entertainment. In case of information, dissemination, and documentation, all private TV channels in Bangladesh serve more entertainment and less public service information, whereas, BTV＇s focus is evident on more PI. The owners and operators of private channels think first of their business profit as well as pressure from government and political parties. During formulating planning and strategies or building program content, they become cautious as they fear that the government become angry and shut down the channel.展开更多
A new digital transmitter based on delta sigma modulator( DSM) with bus-splitting is presented in this paper. The second order low pass error-feedback delta sigma modulator( EF-DSM) is focused. The signal to noise rat...A new digital transmitter based on delta sigma modulator( DSM) with bus-splitting is presented in this paper. The second order low pass error-feedback delta sigma modulator( EF-DSM) is focused. The signal to noise ratio( SNR) of the EF-DSM is derived for different bus-splitting bits.Following the EF-DSM,a multi-bit digital up mixer is used for carrier frequency transform. In order to validate the theory of bus-splitting,two types of transmitters are implemented on FPGA for comparison,in which one is with non-bus-splitting and the other is with bus-splitting. The FPGA implemented transmitter with bus-splitting promotes the maximum operation speed by 39%,and reduces hardware consumptions more than 16%. Both single tone and orthogonal frequency division multiplexing( OFDM) signal source are used to evaluate the proposed transmitter.展开更多
文摘以5G为代表的未来移动接入网将采用集中式的云化网络架构,即基带处理单元(baseband unit,BBU)部署在中心机房,而远端射频单元(remote radio head,RRH)只保留射频处理功能或部分基带处理功能,二者的通信由前传链路承载.目前,以基于以太的通用公共射频接口(Ethernet common public radio interface,eCPRI)为代表的采用移动通信物理层功能单元解耦的前传接口逐渐成为业界的一大主流,随之带来的问题是在这种接口划分下,前传接口数据量会随着移动业务量的变化而波动.为了保证高负载时期的链路传输质量,部署的链路容量往往参考链路峰值速率,这导致链路的利用率整体较低.针对此问题,本文提出了一种弹性量化精度的方案,在高负载状态采用低量化位数来降低前传接口链路的峰值速率,从而节省链路资源的部署.该方案通过仿真与实验进行了验证,结果显示此方案可以大约节省38%的链路资源.
文摘In Bangladesh, more than a dozen of private TV channels are operating and about 10 new channels are waiting with green signal for transmission. Bangladesh Television （BTV）, the only government owned and administered, and known as structurally a biased institution serves the audience the public service information most. At the same time it serves purposes of incumbent government. Public information （PI） broadcast means broadcasting towards public welfare which may bring about change in the betterment of life and work of people. Its main focus would be on information, education, and motivation values rather than entertainment. In case of information, dissemination, and documentation, all private TV channels in Bangladesh serve more entertainment and less public service information, whereas, BTV＇s focus is evident on more PI. The owners and operators of private channels think first of their business profit as well as pressure from government and political parties. During formulating planning and strategies or building program content, they become cautious as they fear that the government become angry and shut down the channel.
基金Supported by the National Natural Science Foundation of China(No.61674037)National Key Research and Development Program of China(No.2016YFC0800400)+1 种基金the Priority Academic Program Development of Jiangsu Higher Education Institutionsthe National Power Grid Corp Science and Technology Project(No.SGTYHT/16-JS-198)
文摘A new digital transmitter based on delta sigma modulator( DSM) with bus-splitting is presented in this paper. The second order low pass error-feedback delta sigma modulator( EF-DSM) is focused. The signal to noise ratio( SNR) of the EF-DSM is derived for different bus-splitting bits.Following the EF-DSM,a multi-bit digital up mixer is used for carrier frequency transform. In order to validate the theory of bus-splitting,two types of transmitters are implemented on FPGA for comparison,in which one is with non-bus-splitting and the other is with bus-splitting. The FPGA implemented transmitter with bus-splitting promotes the maximum operation speed by 39%,and reduces hardware consumptions more than 16%. Both single tone and orthogonal frequency division multiplexing( OFDM) signal source are used to evaluate the proposed transmitter.
