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Robust Packet Video Transport Over Wireless Fading Channels Using a Joint Source-channel Coding Approach 总被引:2,自引:2,他引:0
In this paper, we address the problem of robust video transmission over wireless networks. Specifically, we consider packet
video transmission over wireless IP networks based on the RTP/UDP/IP protocol stack. Digital video delivered over wireless
networks is expected to suffer quality degradation from both packet loss and bit errors in the payload. In this paper, both
packet loss and bit errors in the payload are considered and the performance of a joint source-channel coding (JSCC) approach
employing forward error-correction (FEC) coding schemes for H.263 + video transmission is studied. Results indicate that
with an appropriate JSCC approach, FEC-based error-control techniques can significantly improve the packetization efficiency
for a given end-to-end quality requirement and lead to more acceptable video delivery quality over time-varying wireless networks.
Another important observation is that with a JSCC approach the fading effects of wireless links upon end-to-end video quality
are substantially decreased compared to a system without using channel coding, resulting in attractive robust performance
characteristics.
相似文献
Yong PeiEmail: |
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In this paper, a novel trellis‐coded spatial modulation (TCSM) design method is presented and analyzed. Inspired by the key idea of trellis‐coded modulation (TCM), the detailed analysis is firstly provided on the unequal error protection performance of spatial modulation constellation. Subsequently, the Ungerboeck set partitioning rule is proposed and applied to develop a general method to design the novel TCSM schemes. Different from the conventional TCSM approaches, the novel one based on the Ungerboeck set partitioning rule has similar properties as the classic TCM, which has simple but effective code design criteria. Moreover, the novel designed schemes are robust and adaptive to the generalized Rician fading channels, which outperform the traditional TCSM ones. For examples, the novel 4‐, 8‐, and 16‐state TCSM schemes are constructed by employing different transmit antennas and different modulation schemes in different channel conditions. Simulation results clearly demonstrate the advantages of the novel TCSM schemes over the conventional ones. 相似文献
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该文提出了两种新的适用于时变信道下空时分组编码多用户系统的解码器设计方案。空时分组编码多用户系统下,传统的迫零(Zero Forcing, ZF)和最小均方误差(Minimum Mean Squared Error, MMSE)解码器设计均假定信道准静态衰落。信道时变时,这些传统解码器在解码某用户信号时引入符号间干扰(Inter-Symbol Interference, ISI),且这种干扰随信道时变增大而增加。基于此,该文设计了两种新的解码器,该解码器可显著降低信道时变的影响。仿真结果表明,随信噪比(Signal-to-Noise Ratio, SNR)增加,两种传统解码器均出现误码率性能平层,而新解码器获得了显著的性能改善。 相似文献
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Decision fusion rules for Wireless Sensor Networks (WSNs) under Nakagami fading channels are investigated in this paper. Considering the application limitation of Likelihood Ratio Test fusion rule based on information of Channel Statistics using Series expansion (LRT-CSS), and the detection performance limitation of the Censoring based Mixed Fusion rule (CMF), a new LRT fusion rule based on information of channel statistics has been presented using Laplace approximation (LRT-CSL). Theoretical analysis and simulations show that the proposed fusion rule provides better detection performance than the Censoring based Mixed Fusion (CMF) and LRT-CSS fusion rules. Furthermore, compared with LRT-CSS fusion rule, the proposed fusion rule expands the application range of likelihood ratio test fusion rule. 相似文献
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该文针对时变频率选择性衰落信道下高阶连续相位调制(CPM)信号盲均衡中存在的均衡性能较差、复杂度较高以及收敛速度慢等问题,从双向自适应信道均衡的角度出发,将线性调制信号均衡中使用的前后向自适应软输入软输出(FABA-SISO)算法推广,建立一种新的基于FABA-SISO的信道盲均衡方法,并结合逐幸存处理(PSP)思想和Kalman滤波,提出一种适用于高阶CPM信号的自适应盲均衡算法。该算法通过使用FABA-SISO算法,同时利用过去、现在和将来的观察数据进行Kalman滤波信道估计,有效改善了信道估计的精度,同时使用PSP算法来降低系统的复杂度,使得算法具有较好的工程应用性。仿真结果表明所提算法具有良好的盲均衡性能以及收敛性。 相似文献
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针对无线 Mesh 网络中传统单径路由协议的不足,提出一种基于动态源路由协议(DSR)的多路径路由算法(IDSR).该算法通过在路由发现过程引入带宽和最大转发次数等限制条件,保证了多条路由请求信息的获取;通过在节点不相交的多径选择过程中引入多 QoS 路由代价函数,有效地实现多路径的选择;通过提供多 QoS 保障,使算法具有较高的求解效率,避免了单径路由的不稳定等特点.实验结果表明,IDSR 算法在无线 Mesh 网络的路由中具有更好的 QoS 性能. 相似文献
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Bojana Z. Nikolic Mihajlo C. Stefanovic Stefan R. Panic Jelena A. Anastasov Borivoje Milosevic 《ETRI Journal》2011,33(3):320-325
This paper considers the effects of simultaneous correlated multipath fading and shadowing on the performances of a signal‐to‐interference ratio (SIR)‐based dual‐branch selection combining (SC) diversity receiver. This analysis includes the presence of cochannel interference. A generalized fading/shadowing channel model in an interference‐limited correlated fading environment is modeled by generalized‐K distribution. Closed‐form expressions are obtained for probability density function and cumulative distribution function of the SC output SIR, as well as for the outage probability. Based on this, the influence of various fading and shadowing parameter values and the correlation level on the outage probability is examined. 相似文献
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《电子学报:英文版》2017,(5):1032-1040
Wireless LAN controller (WLC) is used to manage and control Access points (APs) in Wireless local area network (WLAN).Proxy mobile IPv6 (PMIPv6) protocol supports network-layer mobility in WLC based WLAN.However,it introduces extra delay in delivering packets from the APs to the WLC.We use Mobile access gateway (MAG) chain to reduce packet delay.The handoff delay and packet delivery delay under the proposed scheme are derived,based on which we formulate the delay minimization problem whose solution leads to the optimal MAG chain length.Numerical analysis results indicate that the proposed scheme outperforms the existing scheme in terms of delay in the case when the delay between Local mobility anchor (LMA) and WLC is relatively greater than the delay between two neighboring WLCs.The proposed scheme is able to reduce packet loss resulting from the traditional handoff procedure introduced in the PMIPv6 protocol and that due to delay limitation. 相似文献