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Efficient unequal error protection for online fountain codes 被引量:1
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作者 SHI Pengcheng WANG Zhenyong +1 位作者 LI Dezhi LYU Haibo 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第2期286-293,共8页
In this paper,an efficient unequal error protection(UEP)scheme for online fountain codes is proposed.In the buildup phase,the traversing-selection strategy is proposed to select the most important symbols(MIS).Then,in... In this paper,an efficient unequal error protection(UEP)scheme for online fountain codes is proposed.In the buildup phase,the traversing-selection strategy is proposed to select the most important symbols(MIS).Then,in the completion phase,the weighted-selection strategy is applied to provide low overhead.The performance of the proposed scheme is analyzed and compared with the existing UEP online fountain scheme.Simulation results show that in terms of MIS and the least important symbols(LIS),when the bit error ratio is 10-4,the proposed scheme can achieve 85%and 31.58%overhead reduction,respectively. 展开更多
关键词 online fountain code random graph unequal error protection(uep) rateless code
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Joint resource allocation for MIMO-OFDM video transmission systems with unequal error protection 被引量:3
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作者 张成文 刘鑫 谭学治 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2012年第2期119-124,共6页
To improve the performance of MIMO-OFDM video transmission systems on the limitation of wireless bandwidth and transmitting power,we propose an adaptive joint resource allocation algorithm with unequal error protectio... To improve the performance of MIMO-OFDM video transmission systems on the limitation of wireless bandwidth and transmitting power,we propose an adaptive joint resource allocation algorithm with unequal error protection(UEP) based on joint source-channel coding(JSCC) according to H.264 video compression standard and RCPT channel coding.According to different thresholds of the average SNR of subchannels,the algorithm dynamically allocates the source coding parameters of original video data and the channel coding parameters of RCPT,which realizes UEP for the compressed video data of different importance.Through the bit and power allocation based on MQAM modulation and the subspace allocation based on beamforming technology for different subcarriers,an adaptive joint resource allocation making full use of space-frequency domain resources have been realized.The simulation results indicate that the algorithm improves the adaptability of video transmission systems in different wireless environments and the quality of video retrieval. 展开更多
关键词 video transmission MIMO-OFDM unequal error protection joint source-channel coding
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Feedback-based unequal error protection fountain code over device-to-device broadcast
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作者 黄盖世 费泽松 +2 位作者 曹聪哲 邢成文 匡镜明 《Journal of Beijing Institute of Technology》 EI CAS 2014年第4期534-540,共7页
To enhance encoding efficiency, an unequal error protection (UEP) broadcast scheme based on one additional feedback is proposed. Different from the equal probability selection for source packets in traditional fount... To enhance encoding efficiency, an unequal error protection (UEP) broadcast scheme based on one additional feedback is proposed. Different from the equal probability selection for source packets in traditional fountain encoding, the proposed scheme calculates the packet loss ratio (PLR) according to the feedback results in systematic broadcast phase (SBP) and then optimizes the selection probability for source packets to guarantee higher level error protection for those source packets with larger PLRs. Thus the amount of unnecessarily redundant encoded packets during encoding broadcast phase (EBP) is decreased significantly. Numerical results show that the proposed scheme can recover 60% more packets than the traditional non-feedback broadcast scheme at the ex- pense of tolerably only one feedback procedure. 展开更多
关键词 unequal error protection (uep fountain code FEEDBACK device to device (D2D) BROADCAST
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Study on Unequal Error Protection for Distributed Speech Recognition System
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作者 谢湘 王思遥 刘家康 《Journal of Beijing Institute of Technology》 EI CAS 2006年第2期201-205,共5页
The unequal error protection (UEP) is applied in distributed speech recognition (DSR) system and three schemes are proposed. All of these three schemes are evaluated on the GSM simulating platform for recognizing ... The unequal error protection (UEP) is applied in distributed speech recognition (DSR) system and three schemes are proposed. All of these three schemes are evaluated on the GSM simulating platform for recognizing mandarin digit strings and compared with the equal error protection (EEP) scheme. Experiments show that UEP can protect the data transmitted in DSR system more effectively, which results in a higher word accurate rate of DSR system. 展开更多
关键词 distributed speech recognition (DSR) unequal error protection (uep global system mobile (GSM)
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DESIGN OF IRREGULAR LDPC CODE WITH UNEQUAL ERROR PROTECTION PROPERTY AND ITS PERFORMANCE ANALYSIS ON IMAGE TRANSMISSION
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作者 Wang Ruihua Yin Liuguo +1 位作者 Yu Quan Lu Jianhua 《Journal of Electronics(China)》 2005年第6期658-662,共5页
Based on the property that high degree variable nodes within an irregular LowDensity Parity-Check (LDPC) code have more powerful error-correcting capability than that of low degree variable nodes, a group of irregular... Based on the property that high degree variable nodes within an irregular LowDensity Parity-Check (LDPC) code have more powerful error-correcting capability than that of low degree variable nodes, a group of irregular LDPC codes with Unequal Error Protection (UEP)property is designed in this letter. Simulation results show that the transmission quality of the image may be effectively improved with this class of irregular LDPC code. 展开更多
关键词 Irregular Low-Density Parity-Check (LDPC) code unequal error protection (uep Image transmission
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Turbo-Coded Modulation of EVRC Speech Encoder with Unequal Error Protection for Fading Channels
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作者 阿哈麦德 潘志文 +1 位作者 高西奇 尤肖虎 《Journal of Shanghai Jiaotong university(Science)》 EI 2003年第2期150-156,共7页
The Enhanced Variable Rate Codec (EVRC) is a standard for the Speech Service Option 3 for Wideband Spread Spectrum Digital System, which has been employed in both IS-95 cellular systems and ANSI J-STC-008 PCS (Persona... The Enhanced Variable Rate Codec (EVRC) is a standard for the Speech Service Option 3 for Wideband Spread Spectrum Digital System, which has been employed in both IS-95 cellular systems and ANSI J-STC-008 PCS (Personal Communications Systems). This paper investigated the combination of turbo codes with Unequal Error Protection (UEP) and 16-QAM modulation for EVRC codec of Rate 1 to get power and bandwidth efficient coding scheme. The results show that the UEP system outperforms the Equal Error Protection (EEP) one by 1.45 dB at BER of 10 -5. 展开更多
关键词 enhanced variable rate codec (EVRC) turbo codes unequal error protection (uep) quadrature amplitude modulation (QAM)
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Dependency-aware unequal erasure protection codes
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作者 BOUABDALLAH Amine LACAN Jérme 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第z1期27-33,共7页
Classical unequal erasure protection schemes split data to be protected into classes which are encoded independently. The unequal protection scheme presented in this paper is based on an erasure code which encodes all... Classical unequal erasure protection schemes split data to be protected into classes which are encoded independently. The unequal protection scheme presented in this paper is based on an erasure code which encodes all the data together according to the existing dependencies. A simple algorithm generates dynamically the generator matrix of the erasure code according to the packets streams structure, i.e., the dependencies between the packets, and the rate of the code. This proposed erasure code was applied to a packetized MPEG4 stream transmitted over a packet erasure channel and compared with other classical protection schemes in terms of PSNR and MOS. It is shown that the proposed code allows keeping a high video quality-level in a larger packet loss rate range than the other protection schemes. 展开更多
关键词 Data dependencies integration unequal erasure protection (uep) Lossy networks Reliable video transmissions MPEG4 video codec
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Unequal error protection scheme for layered sources transmission over MIMO systems using spatial diversity and multiplexing technology
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作者 Zhang Yongjian Zhang Kexin +1 位作者 Kang Yanmei Yang Dacheng 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 2015年第3期56-63,共8页
This paper proposes a hybrid scheme of the Alamouti coding and vertical bell labs layered space-time (V-BLAST) with the zero-forcing (ZF) receiver, which can achieve the unequal error protection (UEP) transmissi... This paper proposes a hybrid scheme of the Alamouti coding and vertical bell labs layered space-time (V-BLAST) with the zero-forcing (ZF) receiver, which can achieve the unequal error protection (UEP) transmission in terms of the differences of importance in the layered sources. We analyze the tradeoff between spatial diversity and multiplexing in a mathematical manner, and prove the monotonic behavior of the crosspoint. Based on this scheme, we adopt V-BLAST to provide high data rates for the enhancement layer (EL) bitstreams, and adopt Alamouti coding to guarantee high reliability for the base layer (BL) bitstreams. Meanwhile, to improve the transmission reliability for the layered sources under the multiple-input multiple-output (MIMO) system with the limited-bandwidth and the total limited power, and to raise the frequency bandwidth efficiency, we take the power allocation considered in this proposed scheme. The simulation results show that the hybrid scheme has the average 1.9 dB and 1.3 dB gain in video peak signal-to-noise ratio (PSNR), compared with the pure spatial diversity and pure spatial multiplexing scheme, respectively. 展开更多
关键词 unequal error protection spatial diversity and multiplexing outage probability multiple-input multiple-output (MIMO) powerallocation
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Unequal Error Protection Based on Expanding Window Fountain for Object-Based 3D Audio
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作者 YANG Cheng HU Ruimin +3 位作者 SONG Yucheng SU Liuyue WANG Xiaochen CHEN Wei 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2017年第4期323-328,共6页
This paper proposes an unequal error protection(UEP)coding method to improve the transmission performance of three-dimensional(3D)audio based on expanding window fountain(EWF).Different from other transmissions ... This paper proposes an unequal error protection(UEP)coding method to improve the transmission performance of three-dimensional(3D)audio based on expanding window fountain(EWF).Different from other transmissions with equal error protection(EEP)when transmitting the 3D audio objects.An approach of extracting the important audio object is presented,and more protection is given to more important audio object and comparatively less protection is given to the normal audio objects.Objective and subjective experiments have shown that the proposed UEP method achieves better performance than equal error protection method,while the bits error rates(BER)of the important audio object can decrease from 10^(–3) to 10^(–4),and the subjective quality of UEP is better than that of EEP by 14%. 展开更多
关键词 object-based 3D audio unequal error protection equal error protection
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基于EWF的H.264视频流UEP传输方案 被引量:3
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作者 侯春萍 倪春亚 侯永宏 《天津大学学报》 EI CAS CSCD 北大核心 2012年第4期309-313,共5页
为提高H.264码流在无线传输中的鲁棒性,提出了一种基于数据分割和扩展窗喷泉(EWF)码的H.264视频的不等差错保护策略.通过H.264数据分割获取重要性不同的信息比特,采用EWF码对其进行分窗,分别采用鲁棒孤波度分布完成LT编码,实现不等差错... 为提高H.264码流在无线传输中的鲁棒性,提出了一种基于数据分割和扩展窗喷泉(EWF)码的H.264视频的不等差错保护策略.通过H.264数据分割获取重要性不同的信息比特,采用EWF码对其进行分窗,分别采用鲁棒孤波度分布完成LT编码,实现不等差错保护.仿真结果表明,该算法具有较好的抗误码特性,可以提高重建图像的峰值信噪比值,从而保证了视频传输的可靠性. 展开更多
关键词 LT码 H.264 EWF 数据分割 不等差错保护
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直升机助降紫外光通信中分步式UEP-LT码研究 被引量:1
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作者 赵太飞 刘雪 刘一杰 《计算机工程》 CAS CSCD 北大核心 2016年第9期83-88,93,共7页
直升机应急起降中紫外光通信数据决定了助降过程的安全性,需要对数据码流中的重要数据提供更强保护。针对该问题,结合重复信息块方法对扩展窗函数(EWF)法,提出一种分步式非均等数据保护的LT码(SUEPLT)。在二进制删除信道下对重复信息块... 直升机应急起降中紫外光通信数据决定了助降过程的安全性,需要对数据码流中的重要数据提供更强保护。针对该问题,结合重复信息块方法对扩展窗函数(EWF)法,提出一种分步式非均等数据保护的LT码(SUEPLT)。在二进制删除信道下对重复信息块方法、EWF方法和SUEP-LT进行仿真和对比,结果表明,SUEP-LT编码方式具有更强的非均等保护特性,在牺牲少量整体数据可靠性情况下可明显提高重要等级数据的可靠性,保障直升机起降中重要数据的优先可靠传输,增强直升机起降的安全性。 展开更多
关键词 紫外光通信 LT码 非均等差错保护 删除信道 直升机助降
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结合小波包分解的MIMO图像传输UEP策略 被引量:2
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作者 闵卫锋 《电子设计工程》 2018年第2期71-74,79,共5页
为了更好地表征重构图像的纹理等高频信息,提出了两种结合小波包分解的MIMO图像传输不等差错保护(unequal error protection,UEP)方案。首先基于小波包分解进行原始图像压缩编码,进而分别采用固定信道编码方案和自适应信道编码方案,为... 为了更好地表征重构图像的纹理等高频信息,提出了两种结合小波包分解的MIMO图像传输不等差错保护(unequal error protection,UEP)方案。首先基于小波包分解进行原始图像压缩编码,进而分别采用固定信道编码方案和自适应信道编码方案,为具有不等重要性的信源压缩码流提供UEP。仿真结果表明:基于固定信道编码及自适应信道编码的两种UEP方案性能明显优于均等差错保护方案,有效地改善了图像的重构质量。 展开更多
关键词 小波包分解 联合信源信道编码 不等差错保护 码率分配
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UEP MQAM方案及在数字电视地面广播中的应用研究 被引量:1
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作者 李光球 《电子学报》 EI CAS CSCD 北大核心 1999年第10期111-113,共3页
本文提出基于格状编码调制(TCM) 的不等差错保护(UEP)16QAM( 正交幅度调制) 方案和64QAM 方案,与通常的MQAM 相比,UEPMQAM 方案的不重要数据可获得稍好的误码性能,而重要数据可获得9-54 ~1... 本文提出基于格状编码调制(TCM) 的不等差错保护(UEP)16QAM( 正交幅度调制) 方案和64QAM 方案,与通常的MQAM 相比,UEPMQAM 方案的不重要数据可获得稍好的误码性能,而重要数据可获得9-54 ~11-46dB的渐近编码增益.欧洲的地面数字电视标准采用多分辨率广播,本文研究UEPMQAM 展开更多
关键词 格状编码调制 数字电视 uep 正交幅度调制 应用
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信道自适应UEP技术在H.264视频通信系统中的应用 被引量:1
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作者 李虓江 《电视技术》 北大核心 2004年第3期4-7,共4页
在进行基于H.264标准的视频通信系统设计时,为提高编码视频流的抗误码性能以及编码器的编码效率,提出了一种信道自适应非平等误码保护UEP技术。该技术可根据反馈的信道状态信息自适应地确定H.264编码视频流在网络适配层NAL中的工作模式... 在进行基于H.264标准的视频通信系统设计时,为提高编码视频流的抗误码性能以及编码器的编码效率,提出了一种信道自适应非平等误码保护UEP技术。该技术可根据反馈的信道状态信息自适应地确定H.264编码视频流在网络适配层NAL中的工作模式,在丢包信道中结合人眼的视觉特性重新对编码视频信息进行分区并分别采用不同优先级的误码保护。仿真实验表明,在有效提高H.264视频通信系统中解码器输出重构视频图像视觉质量的同时,进一步降低编码器端数据包的打包开销,从而提高编码器的编码效率。 展开更多
关键词 信道自适应 uep H.264 视频通信 非平等误码保护 网络适配层 丢包率
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一种改进的UEP喷泉码算法及其在FGS系统中的应用
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作者 赵旦峰 钱晋希 吴宇平 《系统工程与电子技术》 EI CSCD 北大核心 2011年第1期170-172,232,共4页
在网络视频流的传输中,针对可分级视频编码(scalable video coding,SVC)的精细粒度质量可分级(fine-grain quality scalable,FGS)方式,提出了一种改进的不等差错保护(unequal error protected,UEP)的喷泉码算法,并将UEP喷泉码与FGS结合... 在网络视频流的传输中,针对可分级视频编码(scalable video coding,SVC)的精细粒度质量可分级(fine-grain quality scalable,FGS)方式,提出了一种改进的不等差错保护(unequal error protected,UEP)的喷泉码算法,并将UEP喷泉码与FGS结合,得出了改进UEP喷泉码的FGS系统。其核心思想是对FGS中的基本层与增强层截取不等长度的原始信息,利用喷泉码译码概率对原始信息长度敏感的特性,使得FGS的基本层数据与增强层数据以不等的概率译码。在无反馈信道的情况下,保证了基本层的优先性,提高信道利用率,并且喷泉码可以自适应网络信道环境,接收端可以根据具体的网络环境,以最大概率恢复出当地的原始信息。理论分析和仿真结果表明,采用UEP喷泉码的FGS系统,能够很好地实现基本层与增强层的数据不等保护能力,提高了传统FGS系统的性能。 展开更多
关键词 可分级视频编码 喷泉码 不等差错保护
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基于嵌入式码流UEP的有噪信道图像传输方法
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作者 王哲 张晓林 《系统工程与电子技术》 EI CSCD 北大核心 2010年第10期2243-2247,共5页
针对基于嵌入式码流不等差错保护(unequal error protection,UEP)的有噪信道图像传输,提出了一种码率分配方案(rate allocation scheme,RAS)边信息编码传输方法,分析了其实际可达最优传输性能。首先,给出了考虑RAS边信息传输的信源建模... 针对基于嵌入式码流不等差错保护(unequal error protection,UEP)的有噪信道图像传输,提出了一种码率分配方案(rate allocation scheme,RAS)边信息编码传输方法,分析了其实际可达最优传输性能。首先,给出了考虑RAS边信息传输的信源建模、系统性能评价和最优RAS求解方法。然后,进一步证明了最优RAS具有码率分段的形式,提出了一种有效的基于游程长度编码的压缩编码方法。最后,采用所提出的边信息编码传输方法,分析了不同传输策略下的图像传输方法实际可达最优性能,可得到相应的系统设计准则。 展开更多
关键词 图像通信 信源信道联合编码 嵌入式图像编码 不等差错保护
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基于TCM的UEP16QAM和64QAM方案 被引量:1
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作者 李光球 《电子科学学刊》 CSCD 2000年第1期156-159,共4页
本文提出基于格状编码调制(TCM)的非均匀星座不等差错保护(UEP)16QAM(正交幅度调制)和64QAM方案,与通常的均匀星座M状态QAM(MQAM)相比,UEP MQAM方案的重要数据和不重要数据均可获得数个分贝的编码增益。
关键词 格状编码调制 不等差错保护 分级传输
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一种基于FGS和UEP的无线视频传输方案
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作者 熊馨 刘海燕 丰春霞 《郑州轻工业学院学报(自然科学版)》 CAS 2010年第3期106-109,共4页
针对无线网络带宽波动大、误码率高的特点,提出一种基于FGS和UEP的无线视频传输方案.利用FGS码流的特点,适应无线信道质量的变化;同时根据信道反馈信息,提出了视频数据分级保护策略,对不同的视频数据采取不同的保护力度,提高了视频传输... 针对无线网络带宽波动大、误码率高的特点,提出一种基于FGS和UEP的无线视频传输方案.利用FGS码流的特点,适应无线信道质量的变化;同时根据信道反馈信息,提出了视频数据分级保护策略,对不同的视频数据采取不同的保护力度,提高了视频传输的质量. 展开更多
关键词 FGS 无线网络 视频 非等重误码保护
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具有UEP特性的LT编码方案
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作者 何秀慧 蒋敏兰 《计算机工程》 CAS CSCD 北大核心 2011年第22期74-76,共3页
图像和视频文件在传输中对数据可靠性要求较高。为此,提出一种具有不等差错保护(UEP)特性的LT编码方案。研究无线信道中具有不等差错保护特性的LT码,通过增加适量重要信息比特,提高其在编码过程中被选中的概率,以实现对其保护。实验结... 图像和视频文件在传输中对数据可靠性要求较高。为此,提出一种具有不等差错保护(UEP)特性的LT编码方案。研究无线信道中具有不等差错保护特性的LT码,通过增加适量重要信息比特,提高其在编码过程中被选中的概率,以实现对其保护。实验结果表明,在加性白高斯噪声和快瑞利衰落信道中,该编码方案能呈现较好的UEP特性。 展开更多
关键词 喷泉码 LT码 不等差错保护 置信传播译码
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基于扩展窗的级联型UEP-LT码设计
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作者 师春灵 董金明 杨争艳 《计算机时代》 2013年第8期52-55,共4页
在多媒体数据传输中,重要数据对可靠性要求比较高,在较差信道条件下需要更强的保护,为此提出了一种具有不等保护能力的级联型UEP-LT码方案。该方案先对重要比特(More Important Bits,MIB)数据进行预编码,并引入扩展窗技术进行优化设计,... 在多媒体数据传输中,重要数据对可靠性要求比较高,在较差信道条件下需要更强的保护,为此提出了一种具有不等保护能力的级联型UEP-LT码方案。该方案先对重要比特(More Important Bits,MIB)数据进行预编码,并引入扩展窗技术进行优化设计,然后利用And-Or树分析法对误码率性能进行分析。仿真结果表明,基于扩展窗的级联型UEP-LT码增强了对MIB数据的保护程度,并且降低了对次重要比特(Less Important Bits,LIB)性能的损失,具有良好的UEP特性。 展开更多
关键词 uep—LT码 不等差错保护 扩展窗 与或树
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