This paper evaluates the effect of decision feedback equalizer( DFE) error propagation for400 Gb/s Ethernet( 400 GbE) electrical link in order to propose some effective methods to improve bit error rate( BER). First,a...This paper evaluates the effect of decision feedback equalizer( DFE) error propagation for400 Gb/s Ethernet( 400 GbE) electrical link in order to propose some effective methods to improve bit error rate( BER). First,an analytical model for DFE burst error length distribution is proposed and simulated based on a NRZ electrical link in which a 5-tap DFE combined with a multiple-tap feed forward equalizer( FFE) is included. Then,a detailed derivation for BER considering DFE error propagation is given based on the distribution of burst error run length and the BER performance with and without forward error correction( FEC) is simulated too. After that,this paper investigates several MUX-based FEC interleaving methods including their complexity and latency in order to improve BER further. At last,three FEC interleaving schemes are compared not only in interleaving gain,but also in hardware complexities and latencies. Simulation results show that pre-interleave bit muxing can obtain good tradeoff between BER and complexity for 400 Gb E electrical link.展开更多
针对全景视频数据因量大和延时敏感的特点造成的视频失真问题,提出一种360°全景视频自适应前向纠错(Forward Error Correction,FEC)编码算法,根据实时网络状况对全景视频的图块进行编码比特率和FEC编码率的优化匹配,将全景视频传...针对全景视频数据因量大和延时敏感的特点造成的视频失真问题,提出一种360°全景视频自适应前向纠错(Forward Error Correction,FEC)编码算法,根据实时网络状况对全景视频的图块进行编码比特率和FEC编码率的优化匹配,将全景视频传输质量最大化,减少视频失真。实验结果证明,与传统视频传输算法相比,该算法可以减少视频失真,且视频峰值信噪比(Peak Signal to Noise Ratio,PSNR)提高5~7 dB。展开更多
This paper presents a comprehensive charging operation for an electric-drive-reconfigured onboard charger(EDROC)with active power factor correction(APFC).The charging topology exclusively utilizes the three-phase perm...This paper presents a comprehensive charging operation for an electric-drive-reconfigured onboard charger(EDROC)with active power factor correction(APFC).The charging topology exclusively utilizes the three-phase permanent magnet synchronous motor(PMSM)propulsion system as a three-channel boost-type converter in which only a contactor and a small diode bridge are added.First,the operation scenario of the EDROC is introduced.Second,the relationship between electromagnetic torque and rotor position is investigated.Third,the current ripple cancellation of the EDROC is discussed in detail.Moreover,to implement the single-phase APFC along with charging voltage/current regulation of propulsion battery,control strategies including current balancing and synchronous/interleaving PWM strategies are incorporated.Finally,200W proof-of-concept prototype-based tests are conducted under different operation scenarios.展开更多
基金Supported by the National Natural Science Foundation of China(No.61471119)
文摘This paper evaluates the effect of decision feedback equalizer( DFE) error propagation for400 Gb/s Ethernet( 400 GbE) electrical link in order to propose some effective methods to improve bit error rate( BER). First,an analytical model for DFE burst error length distribution is proposed and simulated based on a NRZ electrical link in which a 5-tap DFE combined with a multiple-tap feed forward equalizer( FFE) is included. Then,a detailed derivation for BER considering DFE error propagation is given based on the distribution of burst error run length and the BER performance with and without forward error correction( FEC) is simulated too. After that,this paper investigates several MUX-based FEC interleaving methods including their complexity and latency in order to improve BER further. At last,three FEC interleaving schemes are compared not only in interleaving gain,but also in hardware complexities and latencies. Simulation results show that pre-interleave bit muxing can obtain good tradeoff between BER and complexity for 400 Gb E electrical link.
文摘针对全景视频数据因量大和延时敏感的特点造成的视频失真问题,提出一种360°全景视频自适应前向纠错(Forward Error Correction,FEC)编码算法,根据实时网络状况对全景视频的图块进行编码比特率和FEC编码率的优化匹配,将全景视频传输质量最大化,减少视频失真。实验结果证明,与传统视频传输算法相比,该算法可以减少视频失真,且视频峰值信噪比(Peak Signal to Noise Ratio,PSNR)提高5~7 dB。
基金This work was supported in part by the National Natural Science Foundation of China(51807098,61673226)and the Six Talent Peaks Project in Jiangsu Province(2015-JY-028).
文摘This paper presents a comprehensive charging operation for an electric-drive-reconfigured onboard charger(EDROC)with active power factor correction(APFC).The charging topology exclusively utilizes the three-phase permanent magnet synchronous motor(PMSM)propulsion system as a three-channel boost-type converter in which only a contactor and a small diode bridge are added.First,the operation scenario of the EDROC is introduced.Second,the relationship between electromagnetic torque and rotor position is investigated.Third,the current ripple cancellation of the EDROC is discussed in detail.Moreover,to implement the single-phase APFC along with charging voltage/current regulation of propulsion battery,control strategies including current balancing and synchronous/interleaving PWM strategies are incorporated.Finally,200W proof-of-concept prototype-based tests are conducted under different operation scenarios.
