In the present work, a construction making possible creation of an additive channel of cardinality s and rank r for arbitrary integers s, r, n (r≤min (n,s-1)), as well as creation of a code correcting err...In the present work, a construction making possible creation of an additive channel of cardinality s and rank r for arbitrary integers s, r, n (r≤min (n,s-1)), as well as creation of a code correcting errors of the channel A is presented.展开更多
The binary extended Golay code has a two-level structure, which can be used in the decoding of the code. However, such structure is not limited to the Golay code, in fact, several binary linear codes can be constructe...The binary extended Golay code has a two-level structure, which can be used in the decoding of the code. However, such structure is not limited to the Golay code, in fact, several binary linear codes can be constructed by a projective method which is related to the structure. In this correspondence, the binary (4n,n + 2k, ≥min(8, n,2d)) linear codes are resulted from quaternary (n,k,d) linear block codes. Based on the structure, the efficient maximum likelihood decoding algorithms can be presented correspondingly for the derived codes.展开更多
针对传统单脉冲布里渊光时域反射系统信号微弱、性能提升受限的问题,提出了一种雪崩光电二极管(APD)检测器本地外差检测的格雷(Golay)编码布里渊光时域反射系统。分析了Golay码应用于该系统的编解码原理及系统外差检测原理,讨论了光纤...针对传统单脉冲布里渊光时域反射系统信号微弱、性能提升受限的问题,提出了一种雪崩光电二极管(APD)检测器本地外差检测的格雷(Golay)编码布里渊光时域反射系统。分析了Golay码应用于该系统的编解码原理及系统外差检测原理,讨论了光纤受激布里渊散射阈值对编码系统平均入纤功率的限制,推导了系统信噪比的数学表达式,研究系统信噪比与APD倍增因子、编码长度的关系,分别得到了APD最佳倍增因子和系统最佳编码长度的表达式。MATLAB仿真结果表明,选用带宽为500 MHz的APD光电检测器和峰值功率50 m W、脉冲宽度100 ns的入纤脉冲时,系统APD倍增因子和编码长度均存在最佳值,系统最佳编码长度的确定不仅依赖于系统的散粒噪声和热噪声功率,还由光纤受激布里渊散射阈值共同决定。经优化计算得,该系统的APD最佳倍增因子为5,最佳编码长度为128位时,在25 km光纤末端的系统信噪比比传统单脉冲系统提高了26.42 d B,温度和应变分辨率分别达到了1.60℃和35.48。展开更多
目前,正交频分复用(Orthogonal Frequency Division Multiplexing,OFDM)技术已被广泛应用于无线电通信技术领域,而同步是正交频分复用(OFDM)技术研究的关键问题之一。因此,基于传统OFDM循环前缀同步法,提出一种新的定时同步算法,引入具...目前,正交频分复用(Orthogonal Frequency Division Multiplexing,OFDM)技术已被广泛应用于无线电通信技术领域,而同步是正交频分复用(OFDM)技术研究的关键问题之一。因此,基于传统OFDM循环前缀同步法,提出一种新的定时同步算法,引入具有良好自相关性的Golay互补序列对,用于修饰OFDM符号,使其具备更好的自相关特性。仿真结果表明,新方法在定时同步上的性能较传统方法有明显提高,在无线电通信技术中具有一定的实用价值。展开更多
文摘In the present work, a construction making possible creation of an additive channel of cardinality s and rank r for arbitrary integers s, r, n (r≤min (n,s-1)), as well as creation of a code correcting errors of the channel A is presented.
文摘The binary extended Golay code has a two-level structure, which can be used in the decoding of the code. However, such structure is not limited to the Golay code, in fact, several binary linear codes can be constructed by a projective method which is related to the structure. In this correspondence, the binary (4n,n + 2k, ≥min(8, n,2d)) linear codes are resulted from quaternary (n,k,d) linear block codes. Based on the structure, the efficient maximum likelihood decoding algorithms can be presented correspondingly for the derived codes.
文摘针对传统单脉冲布里渊光时域反射系统信号微弱、性能提升受限的问题,提出了一种雪崩光电二极管(APD)检测器本地外差检测的格雷(Golay)编码布里渊光时域反射系统。分析了Golay码应用于该系统的编解码原理及系统外差检测原理,讨论了光纤受激布里渊散射阈值对编码系统平均入纤功率的限制,推导了系统信噪比的数学表达式,研究系统信噪比与APD倍增因子、编码长度的关系,分别得到了APD最佳倍增因子和系统最佳编码长度的表达式。MATLAB仿真结果表明,选用带宽为500 MHz的APD光电检测器和峰值功率50 m W、脉冲宽度100 ns的入纤脉冲时,系统APD倍增因子和编码长度均存在最佳值,系统最佳编码长度的确定不仅依赖于系统的散粒噪声和热噪声功率,还由光纤受激布里渊散射阈值共同决定。经优化计算得,该系统的APD最佳倍增因子为5,最佳编码长度为128位时,在25 km光纤末端的系统信噪比比传统单脉冲系统提高了26.42 d B,温度和应变分辨率分别达到了1.60℃和35.48。
文摘目前,正交频分复用(Orthogonal Frequency Division Multiplexing,OFDM)技术已被广泛应用于无线电通信技术领域,而同步是正交频分复用(OFDM)技术研究的关键问题之一。因此,基于传统OFDM循环前缀同步法,提出一种新的定时同步算法,引入具有良好自相关性的Golay互补序列对,用于修饰OFDM符号,使其具备更好的自相关特性。仿真结果表明,新方法在定时同步上的性能较传统方法有明显提高,在无线电通信技术中具有一定的实用价值。