为满足信息传输实时可靠、频谱使用高效灵活等技战术需求,在机间数据链(Intra-Flight Data Link,IFDL)物理层采用了多载波正交频分复用(Orthogonal Frequency Division Multiplexing,OFDM)传输体制。针对其抗干扰性能不足的问题,在突发...为满足信息传输实时可靠、频谱使用高效灵活等技战术需求,在机间数据链(Intra-Flight Data Link,IFDL)物理层采用了多载波正交频分复用(Orthogonal Frequency Division Multiplexing,OFDM)传输体制。针对其抗干扰性能不足的问题,在突发干扰下对系统可靠性理论分析的同时,采用NASA提出的(255,223)Reed Solomon(RS)-(2,1,7)卷积"标准级联码",并与符号卷积交织相结合构成了前向纠错(Forward Error Correction,FEC)级联码方案。仿真结果表明,级联码OFDM系统在一定误码率下、不同IFDL信道环境中,均可获得较高编码增益,从而有效增强了机间数据链OFDM系统可靠性。此外,通过机载定向天线低截获传输,在保证隐蔽性的同时可进一步抑制多径衰落及跟踪干扰。展开更多
We present two constructions for binary self-orthogonal codes. It turns out that our constructions yield a constructive bound on binary self-orthogonal codes. In particular, when the in-formation rate R = 1/2, by our ...We present two constructions for binary self-orthogonal codes. It turns out that our constructions yield a constructive bound on binary self-orthogonal codes. In particular, when the in-formation rate R = 1/2, by our constructive lower bound, the relative minimum distance δ≈ 0.0595 (for GV bound, δ≈ 0.110). Moreover, we have proved that the binary self-orthogonal codes asymptotically achieve the Gilbert-Varshamov bound.展开更多
文摘为满足信息传输实时可靠、频谱使用高效灵活等技战术需求,在机间数据链(Intra-Flight Data Link,IFDL)物理层采用了多载波正交频分复用(Orthogonal Frequency Division Multiplexing,OFDM)传输体制。针对其抗干扰性能不足的问题,在突发干扰下对系统可靠性理论分析的同时,采用NASA提出的(255,223)Reed Solomon(RS)-(2,1,7)卷积"标准级联码",并与符号卷积交织相结合构成了前向纠错(Forward Error Correction,FEC)级联码方案。仿真结果表明,级联码OFDM系统在一定误码率下、不同IFDL信道环境中,均可获得较高编码增益,从而有效增强了机间数据链OFDM系统可靠性。此外,通过机载定向天线低截获传输,在保证隐蔽性的同时可进一步抑制多径衰落及跟踪干扰。
基金supported by the China Scholarship Council, National Natural Science Foundation of China(Grant No.10571026)the Cultivation Fund of the Key Scientific and Technical Innovation Project of Ministry of Education of Chinathe Specialized Research Fund for the Doctoral Program of Higher Education (GrantNo. 20060286006)
文摘We present two constructions for binary self-orthogonal codes. It turns out that our constructions yield a constructive bound on binary self-orthogonal codes. In particular, when the in-formation rate R = 1/2, by our constructive lower bound, the relative minimum distance δ≈ 0.0595 (for GV bound, δ≈ 0.110). Moreover, we have proved that the binary self-orthogonal codes asymptotically achieve the Gilbert-Varshamov bound.
