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Lower bound on BER performance for maximal ratio combining with weighting errors 被引量:1
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作者 盛彬 尤肖虎 《Journal of Southeast University(English Edition)》 EI CAS 2005年第4期379-384,共6页
The theoretical lower bounds on mean squared channel estimation errors for typical fading channels are presented by the infinite-length and non-causal Wiener filter and the exact closed-form expressions of the lower b... The theoretical lower bounds on mean squared channel estimation errors for typical fading channels are presented by the infinite-length and non-causal Wiener filter and the exact closed-form expressions of the lower bounds for different channel Doppler spectra are derived. Based on the obtained lower bounds on mean squared channel estimation errors, the limits on bit error rate (BER) for maximal ratio combining (MRC) with Gaussian distributed weighting errors on independent and identically distributed (i. i. d) fading channels are presented. Numerical results show that the BER performances of ideal MRC are the lower bounds on the BER performances of non-ideal MRC and deteriorate as the maximum Doppler frequency increases or the SNR of channel estimate decreases. 展开更多
关键词 lower bound bit error rate minimum mean-square error channel estimation maximal ratio combining
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EFFICIENT BIT ERROR PROBABILITY EXPRESSION AND VERY TIGHT BOUND FOR MAXIMAL RATIO COMBINING DIVERSITY SYSTEMS OVER RAYLEIGH FADING CHANNEL
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作者 Zhang Lin Qin Jiayin 《Journal of Electronics(China)》 2008年第1期14-19,共6页
Bit Error Probability (BEP) provides a fundamental performance measure for wireless diversity systems. This paper presents two new exact BEP expressions for Maximal Ratio Combining (MRC) diversity systems. One BEP exp... Bit Error Probability (BEP) provides a fundamental performance measure for wireless diversity systems. This paper presents two new exact BEP expressions for Maximal Ratio Combining (MRC) diversity systems. One BEP expression takes a closed form, while the other is derived by treating the squared-sum of Rayleigh random variables as an Erlang variable. Due to the fact that the extant bounds are loose and could not properly characterize the error performance of MRC diversity systems, this paper presents a very tight bound. The numerical analysis shows that the new derived BEP expressions coincide with the extant expressions, and that the new approximation tightly bounds the accurate BEP. 展开更多
关键词 bit error Probability (BEP) Efficient expressions Maximal ratio Combining (MRC) Rayleigh fading channels
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Bit Error Rate (BER) Performance Evaluation of Various Space-time Block Codes in MIMO Wireless Communications
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作者 Sanjay Kumar Sharma Syed Naseem Ahmad 《通讯和计算机(中英文版)》 2010年第3期32-38,共7页
关键词 空时分组码 无线通信 MIMO ber 误码率 评价 性能
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BER Performance Analysis of Asynchronous NOMA with Arbitrary Phase Offset 被引量:1
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作者 Chang Liu Sheng Wu +1 位作者 Chunxiao Jiang Hongwen Yang 《China Communications》 SCIE CSCD 2022年第11期195-208,共14页
An asynchronous transmission scenario for non-orthogonal multiple access(NOMA)user signals with arbitrary phase offset is investigated in this paper.To improve the system performance in the user power-balanced conditi... An asynchronous transmission scenario for non-orthogonal multiple access(NOMA)user signals with arbitrary phase offset is investigated in this paper.To improve the system performance in the user power-balanced conditions,we adopt a synthetic detection method at the receiver,i.e.,the jointly optimal maximal likelihood detection aided triangular successive interference cancellation(JO ML-TSIC)method.Analytical bit error rate(BER)solutions are obtained for a two-user case with the optimal,intentional onehalf symbol period time delay implemented between the user signals.Furthermore,closed-form BER solutions for the case using the triangular successive interference cancellation(TSIC)detection method are also derived for comparisons.Numerical results show that the JO ML-TSIC receiver for the asynchronous system outperforms the TSIC receiver as well as the synchronous successive interference cancellation(SIC)receiver in all the conditions concerned.The results also show that the superiority of the JO ML-TSIC receiver is strengthened when the signals experience flat Rayleigh fading channels compared to the TSIC and the synchronous SIC receivers. 展开更多
关键词 non-orthogonal multiple access(NOMA) asynchronous transmission jointly optimal(JO)maximum likelihood(ML)detection successive interference cancellation(SIC) bit error rate(ber)
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OFDM系统中一种A-MMSE信道估计算法
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作者 叶文伟 《半导体光电》 CAS 北大核心 2024年第2期308-312,共5页
针对正交频分复用(Orthogonal Frequency Division Multiplexing,OFDM)系统中最小均方误差(Minimum Mean Squared Error,MMSE)信道估计算法误码率(BER)高的问题,提出一种平均最小均方误差(Averaged-Minimum Mean Squared Error,A-MMSE)... 针对正交频分复用(Orthogonal Frequency Division Multiplexing,OFDM)系统中最小均方误差(Minimum Mean Squared Error,MMSE)信道估计算法误码率(BER)高的问题,提出一种平均最小均方误差(Averaged-Minimum Mean Squared Error,A-MMSE)信道估计算法。该算法首先基于802.11n标准而构造了一种新的导频结构,收发两端分别进行降采样和过采样处理,利用已知训练序列和导频获得信道频域响应。仿真结果表明,所提出的A-MMSE信道估计算法与传统的MMSE算法相比,在BER为10^(-3)时,信噪比改善了约8dB。因而所提出的信道估计算法能明显改善系统的BER性能。 展开更多
关键词 正交频分复用系统 导频 最小均方误差 误码率
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广义频分复用系统峰均功率比抑制算法
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作者 宁晓燕 刘承赟 +1 位作者 谌星宇 王震铎 《哈尔滨工程大学学报》 EI CAS CSCD 北大核心 2024年第4期794-799,共6页
为了降低广义频分复用系统存在着多载波系统中固有的高峰均功率比问题,本文提出了一种适用于广义频分复用系统的子载波抑制高峰均功率比算法。该算法以限幅法为基础,降低了系统的高峰均功率比,但与限幅法不同的是,该算法几乎不会对带外... 为了降低广义频分复用系统存在着多载波系统中固有的高峰均功率比问题,本文提出了一种适用于广义频分复用系统的子载波抑制高峰均功率比算法。该算法以限幅法为基础,降低了系统的高峰均功率比,但与限幅法不同的是,该算法几乎不会对带外性能及误码率性能造成影响。由于子载波抑制高峰均功率比算法的峰均功率比抑制性能略差于限幅法,因此本文进一步提出将部分序列传输与子载波抑制高峰均功率比结合来进一步抑制系统高峰均功率比的算法。仿真表明:本文提出的算法的高峰均功率比抑制性能与限幅法相同,且不会对系统的带外与误码率性能造成影响。 展开更多
关键词 广义频分复用 高峰均功率比 限幅法 子载波抑制峰均功率比 复杂度 部分传输序列法 带外 误码率
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应答器上行链路信号自适应解调方法的FPGA实现
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作者 李建国 薛千树 陈明福 《科学技术与工程》 北大核心 2024年第20期8715-8722,共8页
为降低电磁干扰对信号传输的影响,分析了应答器上行链路信号传输过程及其易遭受干扰信号的特点,设计了基于符号最小均方误差(least mean square,LMS)算法的自适应解调方法。为在硬件平台中实现该解调方法,通过仿真计算,确定LMS算法的自... 为降低电磁干扰对信号传输的影响,分析了应答器上行链路信号传输过程及其易遭受干扰信号的特点,设计了基于符号最小均方误差(least mean square,LMS)算法的自适应解调方法。为在硬件平台中实现该解调方法,通过仿真计算,确定LMS算法的自适应算法中间变量变化范围,使用截位操作完成权值系数的更新,设置均衡器长度、步长因子、中值滤波系数分别为1、1/64、16,可在不占用过多硬件资源情况下获得良好的解调性能。解调算法在现场可编程门阵列(field programmable gata array,FPGA)上予以验证,实验表明,当信噪比为6 dB时,FPGA中自适应解调误码率为0.000001,在信噪比大于等于6 dB时,实测误码率与仿真分析误码率基本一致;FPGA自适应解调方法在列车不同速度等级下误码率均小于10^(-6)。 展开更多
关键词 应答器 自适应解调 最小均方误差(LMS)算法 现场可编程门阵列(FPGA) 信噪比 误码率
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一种适用于卫星通信的自适应窄带干扰抑制方法
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作者 陈敬乔 张颖 +1 位作者 潘申富 汪颜 《电子信息对抗技术》 2024年第2期20-26,共7页
针对卫星通信系统中的抗干扰问题,提出一种能够根据干扰变化自适应调整策略的干扰抑制方法。该方法通过子带分割、按功率排序、依次陷波等方式进行陷波,然后对比陷波前后信号信噪比的增益,从而确定信噪比增益最大时所对应的子带陷波个数... 针对卫星通信系统中的抗干扰问题,提出一种能够根据干扰变化自适应调整策略的干扰抑制方法。该方法通过子带分割、按功率排序、依次陷波等方式进行陷波,然后对比陷波前后信号信噪比的增益,从而确定信噪比增益最大时所对应的子带陷波个数,最终得到信噪比增益最高也即性能最优的陷波方式。该方法不需要预先进行干扰检测,也不需要寻找和设置门限阈值,就可以对多种类型干扰进行自适应陷波,从而达到有效抑制包含单音、窄带、梳状或部分频带等不同干扰的目的,能够显著改善链路的通信性能,提高通信系统的抗干扰能力。 展开更多
关键词 卫星通信 FFT 干扰抑制 自适应 信噪比 误码性能
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Neural-Polar码:一种基于深度学习的新型信道编码方案 被引量:1
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作者 金林贤 王旭东 吴楠 《重庆邮电大学学报(自然科学版)》 CSCD 北大核心 2024年第3期430-437,共8页
为应对新型移动通信系统智能性的需求以及在难以进行人工建模的复杂信道环境下进行可靠通信的问题,基于Polar码的编译码递归结构提出一种新型神经网络信道编码方案,即Neural-Polar码。该方案利用神经网络将Polar码编译码递归结构中父、... 为应对新型移动通信系统智能性的需求以及在难以进行人工建模的复杂信道环境下进行可靠通信的问题,基于Polar码的编译码递归结构提出一种新型神经网络信道编码方案,即Neural-Polar码。该方案利用神经网络将Polar码编译码递归结构中父、子节点间的线性映射变成非线性映射,引入快速连续抵消(successive cancellation, SC)译码的思想,解决在完全二叉树上构建Neural-Polar码造成网络结构过大的问题。仿真实验表明,Neural-Polar码可以获得优于经典SC译码算法的误码率(bit error rate, BER)和误块率(block error rate, BLER)性能,对网络的联合训练使得Neural-Polar码能够自动学习信道特性,具有更好的信道适应性和鲁棒性。Neural-Polar码将传统的对复杂信道进行人工建模分析的难题交给机器,充分体现出其编译码的智能性。 展开更多
关键词 信道编码 极化码 神经网络 误码率(ber)
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FSO链路中基于平均信噪比的自适应功率传输技术
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作者 吕鹏飞 洪燕青 +1 位作者 荆千纹 刘文尧 《海军航空大学学报》 2024年第2期235-240,282,共7页
文章提出了1种基于平均信噪比(Signal-to-Noise Ratio,SNR)的自适应功率传输技术,旨在补偿大气湍流引起的闪烁效应,以提升自由空间光(Free-Space Optical,FSO)通信系统的性能。在无需大气湍流状态信息估计的情况下,根据接收信号的平均SN... 文章提出了1种基于平均信噪比(Signal-to-Noise Ratio,SNR)的自适应功率传输技术,旨在补偿大气湍流引起的闪烁效应,以提升自由空间光(Free-Space Optical,FSO)通信系统的性能。在无需大气湍流状态信息估计的情况下,根据接收信号的平均SNR来调整发射信号的发射功率,实现基于自适应功率传输技术的大气湍流效应补偿。建立了不同湍流强度下具有不同噪声水平的信道模型,并将所提出的技术与固定阈值判决(Fixed Threshold Decision,FTD)和自适应阈值判决(Adaptive Threshold Decision,ATD)技术进行了比较分析。仿真结果表明,在不同的湍流强度下,该技术的误码率(Bit Error Rate,BER)性能相较于FTD有了显著的提高,并且接近于ATD。因此,该技术可以有效提高FSO链路的通信能力。 展开更多
关键词 自由空间光通信 自适应传输技术 平均信噪比 误码率
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非对称调制的双向全双工车载通信BER性能分析
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作者 肖海林 金晓晴 +1 位作者 邱斌 马得森 《系统工程与电子技术》 EI CSCD 北大核心 2018年第4期904-910,共7页
在车载通信系统中,全双工中继技术可满足车联网的低时延需求以及缓解频谱资源短缺问题。然而,实际车载通信应用中不同信源车辆发送的信息相互独立,节点调制方式往往不对称。这种非对称传输会加剧全双工模式残余自干扰造成的译码错误。... 在车载通信系统中,全双工中继技术可满足车联网的低时延需求以及缓解频谱资源短缺问题。然而,实际车载通信应用中不同信源车辆发送的信息相互独立,节点调制方式往往不对称。这种非对称传输会加剧全双工模式残余自干扰造成的译码错误。针对这一问题,提出一种非对称调制的全双工通信方法,该方法引入网络编码联合调制的解码转发方式解决了非对称调制带来的误码率增大的问题。此外,分析了全双工残余自干扰随功率动态变化情况下的优化约束条件,得到最优功率分配区间。数值分析结果证明:在不同功率区间内,所提方法都可找到最优功率比例,使得系统端到端误比特性能最优。 展开更多
关键词 车载通信系统 双向全双工 残余自干扰 非对称调制 误比特率
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多径信道下基于恒模算法的遥测信号盲均衡
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作者 王刚 杨钖 +1 位作者 韩明 李光 《上海航天(中英文)》 CSCD 2024年第2期62-66,80,共6页
运载火箭在塔架静态测试时易受多径衰落影响,导致遥测信号产生码间干扰。本文对PCM-FM体制遥测信号的多径信道使用恒模算法(CMA)进行盲均衡研究,针对遥测信道中的码间干扰展开理论分析和Matlab仿真,并搭建盲均衡功能测试平台开展实验验... 运载火箭在塔架静态测试时易受多径衰落影响,导致遥测信号产生码间干扰。本文对PCM-FM体制遥测信号的多径信道使用恒模算法(CMA)进行盲均衡研究,针对遥测信道中的码间干扰展开理论分析和Matlab仿真,并搭建盲均衡功能测试平台开展实验验证。结果表明:CMA收敛速度高、误码率低,对多径干扰具有较好的鲁棒性和实用性。 展开更多
关键词 多径效应 遥测信号 恒模算法 盲均衡 误码率
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基于自适应随机共振的水下蓝绿光微弱信号检测
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作者 张建磊 张娟 +4 位作者 朱云周 姚欣钰 吴倩倩 杨祎 贺锋涛 《光子学报》 EI CAS CSCD 北大核心 2024年第3期207-218,共12页
海水的吸收和散射导致光信号严重衰减,使得水下无线光通信系统中低信噪比信号检测成为一大难题。基于此,提出一种自适应随机共振水下蓝绿光微弱信号检测方法。分析了水下弱光信号特点以及随机共振的产生条件,结合多策略融合的粒子群算... 海水的吸收和散射导致光信号严重衰减,使得水下无线光通信系统中低信噪比信号检测成为一大难题。基于此,提出一种自适应随机共振水下蓝绿光微弱信号检测方法。分析了水下弱光信号特点以及随机共振的产生条件,结合多策略融合的粒子群算法与随机共振动态调整系统参数,使系统达到最优匹配状态,进而提升弱光信号的检测性能。搭建了水下无线光通信实验系统进行实验,结果表明,在接收信噪比为-1.7 dB时,使用该方法得到的误码率低至2×10-4,验证了该方法的可行性和有效性。 展开更多
关键词 水下无线光通信 低信噪比 自适应随机共振 多策略融合粒子群算法 误码率
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抗干扰技术在卫星通信工程中的应用研究
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作者 房阳阳 《通信电源技术》 2024年第12期167-169,共3页
在卫星通信工程中,日益严峻的信号干扰问题严重影响着信息传输的稳定性和安全性。针对这一问题,文章深入研究了抗干扰技术在卫星通信工程中的具体应用,探讨时频分析、阵列信号处理、自适应滤波以及前向纠错等多种抗干扰策略。经实验验证... 在卫星通信工程中,日益严峻的信号干扰问题严重影响着信息传输的稳定性和安全性。针对这一问题,文章深入研究了抗干扰技术在卫星通信工程中的具体应用,探讨时频分析、阵列信号处理、自适应滤波以及前向纠错等多种抗干扰策略。经实验验证,实施抗干扰技术后,误码率(Bit Error Rate,BER)降至10-8,信噪比(Signal to Noise Ratio,SNR)平均增长了3.67 dB,性能远超未优化状态。 展开更多
关键词 抗干扰技术 卫星通信工程 误码率(ber) 信噪比(SNR)
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提高MIMO信道BER性能的干扰对齐方案 被引量:3
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作者 周强 吴玉成 《计算机工程》 CAS CSCD 2012年第8期54-56,共3页
为提高多输入多输出(MIMO)X信道的比特误码率(BER)性能,提出一种干扰对齐方案。在发送端将数据按照Alamouti编码方案重复发送,在接收端通过重新配置天线工作模式改变信道系数,构成具有正交结构的等效信道矩阵,通过矩阵运算消除干扰,并... 为提高多输入多输出(MIMO)X信道的比特误码率(BER)性能,提出一种干扰对齐方案。在发送端将数据按照Alamouti编码方案重复发送,在接收端通过重新配置天线工作模式改变信道系数,构成具有正交结构的等效信道矩阵,通过矩阵运算消除干扰,并采用低复杂度的PIC群译码算法进行译码。仿真结果验证了该方案的有效性。 展开更多
关键词 多输入多输出 X信道 干扰对齐 自由度 比特误码率
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Performance analysis and design of MIMO-OFDM system using concatenated forward error correction codes 被引量:3
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作者 Arun Agarwal Saurabh N.Mehta 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第6期1322-1343,共22页
This work investigates the performance of various forward error correction codes, by which the MIMO-OFDM system is deployed. To ensure fair investigation, the performance of four modulations, namely, binary phase shif... This work investigates the performance of various forward error correction codes, by which the MIMO-OFDM system is deployed. To ensure fair investigation, the performance of four modulations, namely, binary phase shift keying(BPSK), quadrature phase shift keying(QPSK), quadrature amplitude modulation(QAM)-16 and QAM-64 with four error correction codes(convolutional code(CC), Reed-Solomon code(RSC)+CC, low density parity check(LDPC)+CC, Turbo+CC) is studied under three channel models(additive white Guassian noise(AWGN), Rayleigh, Rician) and three different antenna configurations(2×2, 2×4, 4×4). The bit error rate(BER) and the peak signal to noise ratio(PSNR) are taken as the measures of performance. The binary data and the color image data are transmitted and the graphs are plotted for various modulations with different channels and error correction codes. Analysis on the performance measures confirm that the Turbo + CC code in 4×4 configurations exhibits better performance. 展开更多
关键词 bit error rate (ber) convolutional CODE (CC) forward error correction peak signal to noise ratio (PSNR) Turbo CODE
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Downlink BER performance analysis of distributed antenna systems over shadowed Rayleigh fading channels
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作者 陈华敏 陈明 《Journal of Southeast University(English Edition)》 EI CAS 2009年第2期167-170,共4页
Due to the complexity of the composite fading channel, a new simplified channel model is proposed to analyze the bit error ratio(BER) performance of the distributed antenna system (DAS). First, instead of the gamm... Due to the complexity of the composite fading channel, a new simplified channel model is proposed to analyze the bit error ratio(BER) performance of the distributed antenna system (DAS). First, instead of the gamma-log-normal distribution, the log-normal distribution is applied to describe the output signal to noise ratio(SNR) after maximal ratio combining (MRC) at the receiver. Then, assuming that the channel state information(CSI) is available to the transmitter, by employing the Gauss-Hermite integral, an approximate analytical expression of the BER is derived for the downlink of the DAS with antenna selective transmission and MRC. Finally, the results of a Monte Carlo simulation show that the analytical results match the simulation results. Therefore, it can be concluded that the proposed approximate channel model is effective and accurate, and the derived analytical expression can be used to evaluate the real system performance. 展开更多
关键词 distributed antenna system bit error ratio shadowed Rayleigh fading log-normal gamma-log-normal
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Multi-Bit Sliding Stack Decoding Algorithm for OVXDM 被引量:3
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作者 peng lin yafeng wang daoben li 《China Communications》 SCIE CSCD 2018年第4期179-191,共13页
Overlapped x domain multiplexing(OVXDM) is a promising encoding technique to obtain high spectral efficiency by utilizing inter-symbol interference(ISI) intelligently. However, the computational complexity of maximum ... Overlapped x domain multiplexing(OVXDM) is a promising encoding technique to obtain high spectral efficiency by utilizing inter-symbol interference(ISI) intelligently. However, the computational complexity of maximum likelihood sequence detection(MLSD) increases exponentially with the growth of spectral efficiency in OVXDM, which is unbearable for practical implementations. In this paper, based on a novel path metric associating adjacent symbols, we propose a multi-bit sliding stack decoding(Multi-Bit SSD) algorithm to achieve multiple-bit decoding simultaneously in OVXDM. Theoretical analysis is provided for the algorithm, which indicates the relationship between the performance and parameters including multiplexing waveform, overlapping fold and sliding window size. Simulation results show that the proposed algorithm can achieve better decoding performance and higher spectral efficiency than conventional fast decoding algorithms. 展开更多
关键词 overlapped multiplexing princi-ple maximum likelihood (ML) rule spectralefficiency bit error rate (ber).
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Improving the BER performance of turbo codes with short frame size based on union bound 被引量:1
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作者 邵霞 Li Ping Zhang Weidang 《High Technology Letters》 EI CAS 2015年第3期309-314,共6页
timizing the formula, the energy for every bit of the codeword is optimized to achieve the minimum BER at high SNR region. At last, an adjustable parameter is employed to compensate the degrada- tions of BER at low an... timizing the formula, the energy for every bit of the codeword is optimized to achieve the minimum BER at high SNR region. At last, an adjustable parameter is employed to compensate the degrada- tions of BER at low and moderate SNR regions. Case studies indicate that the improvements of BER for turbo codes with short frame size are significant at a wide range of SNR 展开更多
关键词 channel coding bit error rate (ber energy allocation turbo code
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BER ANALYSIS OF A GMSK SYSTEM USING DECISION FEEDBACK 被引量:1
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作者 He Xiandeng Pei Changxing 《Journal of Electronics(China)》 2008年第4期544-551,共8页
There are considerable literatures on the Bit Error Rate(BER)evaluation of DifferentialDetection of Gaussian Minimum Shift Keying(DDGMSK)system using Decision Feedback(DF),butmost of them give the performance based on... There are considerable literatures on the Bit Error Rate(BER)evaluation of DifferentialDetection of Gaussian Minimum Shift Keying(DDGMSK)system using Decision Feedback(DF),butmost of them give the performance based on the Monte Carlo Error Counting(MCEC)technique.Fromthe probability distribution of the phase angle between two vectors perturbed by Gaussian noises,theformulae of BER are derived for the performance analysis of DDGMSK system with DF in this letter.Considering the m-bit dock-tailed sequence,the new formulae of Gaussian Minimum Shift Keying(GMSK)modulated phase and the Time-Varying Signal to Noise Ratio(TVSNR)of the demodulatedsignal are presented,and it is proved that the relationship between the TVSNR of the demodulatedsignal and the size of eye opening is not inevitable.Simulation results show that the theoretical in-vestigation gives analogous results with the MCEC technique.The formulae presented are useful for theperformance analysis of systems using GMSK as modulating and demodulating method,for instance,the analysis of synchronous performance of frequency-hopping communication system. 展开更多
关键词 Gaussian Minimum Shift Keying (GMSK) Differential detection Decision Feedback (DF) bit error Rate (ber
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