A new family of optical codes for Optical Code-division Multiple Access (OCDMA) systems, named as Optical Complementary Codes (OCCs), is proposed in this paper. The constructions of these codes consist of multiple sub...A new family of optical codes for Optical Code-division Multiple Access (OCDMA) systems, named as Optical Complementary Codes (OCCs), is proposed in this paper. The constructions of these codes consist of multiple sub-codes, and the codes have an auto-correlation interference constraint as 0 and a cross-correlation interference constraint as 1. Compared with conventional optical codes such as OPCs, OOCs and 2-D OOCs, the OCC has a shorter code length and higher code efficiency with better correlation property.展开更多
A new set of binary sequences-Periodic Complementary Binary Sequence Pair (PCSP) is proposed. A new class of block design-Difference Family Pair (DFP) is also proposed.The relationship between PCSP and DFP, the proper...A new set of binary sequences-Periodic Complementary Binary Sequence Pair (PCSP) is proposed. A new class of block design-Difference Family Pair (DFP) is also proposed.The relationship between PCSP and DFP, the properties and existing conditions of PCSP and the recursive constructions for PCSP are given.展开更多
In this paper, a multicarrier DS-CDMA system which employs Z-Complementary Se- quences (ZCS) as spreading code is investigated. The new system can not only eliminate multipath interference and Multiple Access Interfer...In this paper, a multicarrier DS-CDMA system which employs Z-Complementary Se- quences (ZCS) as spreading code is investigated. The new system can not only eliminate multipath interference and Multiple Access Interference (MAI), but also support flexible number of users com- pared with system using Orthogonal Complementary (OC) codes. Multicarrier DS-CDMA using OC codes can be regarded as a special case of our proposed system. Zero Correlation Zone (ZCZ) of ZCS can be flexibly adjusted to meet the requirements on the user number and maximum multipath and in- ter-user delay, in this way, more users can be supported without losing interference-free property. The effectiveness of the proposed system is validated through theoretical analysis and simulation results.展开更多
Saleh等在期刊Journal of Applied Mathematics and Computing的第56卷第1期上发表论文“On complementary dual qusai-twist codes”[20],证明了拟扭转码在一定条件下是线性补对偶码(LCD码)。对其中的四个关键性定理进行修正与完善,进...Saleh等在期刊Journal of Applied Mathematics and Computing的第56卷第1期上发表论文“On complementary dual qusai-twist codes”[20],证明了拟扭转码在一定条件下是线性补对偶码(LCD码)。对其中的四个关键性定理进行修正与完善,进一步给出拟扭转码是LCD的充分条件,并由此构造出许多具有优良参数的LCD码。展开更多
A general construction of inter-group complementary (IGC) codes is proposed based on perfect complementary (PC) codes,interleaving operation,and the orthogonal matrix.The correlation properties of the newly constructe...A general construction of inter-group complementary (IGC) codes is proposed based on perfect complementary (PC) codes,interleaving operation,and the orthogonal matrix.The correlation properties of the newly constructed IGC codes can be described as follows:(1) the autocorrelation sidelobes of the codes are zeros in the zero correlation zone (ZCZ);(2) the cross-correlation functions (CCFs) between any two different codes of the same group are zeros in the ZCZ;(3) the CCFs between any two codes of different groups are zeros everywhere.The key point of this construction is that the ZCZ length of the generated IGC codes can be chosen flexibly.It is well known that there is a limitation between the ZCZ length and the number of mates;that is,the smaller is the length of ZCZ,the more are the IGC codes that can be generated.Therefore,if we can choose the ZCZ length of the IGC codes flexibly according to the requirement of the system,more users can be accommodated in the system.展开更多
文摘A new family of optical codes for Optical Code-division Multiple Access (OCDMA) systems, named as Optical Complementary Codes (OCCs), is proposed in this paper. The constructions of these codes consist of multiple sub-codes, and the codes have an auto-correlation interference constraint as 0 and a cross-correlation interference constraint as 1. Compared with conventional optical codes such as OPCs, OOCs and 2-D OOCs, the OCC has a shorter code length and higher code efficiency with better correlation property.
基金Supported by National Natural Science Foundation of China (69972042),Natural Science Fund of Hebei Provice(599245)and Science Foundation of Yanshan University
文摘A new set of binary sequences-Periodic Complementary Binary Sequence Pair (PCSP) is proposed. A new class of block design-Difference Family Pair (DFP) is also proposed.The relationship between PCSP and DFP, the properties and existing conditions of PCSP and the recursive constructions for PCSP are given.
基金Supported by the National Natural Science Foundation of China (No.60772087, No.90604035)111 Project (No.111- 2-14)
文摘In this paper, a multicarrier DS-CDMA system which employs Z-Complementary Se- quences (ZCS) as spreading code is investigated. The new system can not only eliminate multipath interference and Multiple Access Interference (MAI), but also support flexible number of users com- pared with system using Orthogonal Complementary (OC) codes. Multicarrier DS-CDMA using OC codes can be regarded as a special case of our proposed system. Zero Correlation Zone (ZCZ) of ZCS can be flexibly adjusted to meet the requirements on the user number and maximum multipath and in- ter-user delay, in this way, more users can be supported without losing interference-free property. The effectiveness of the proposed system is validated through theoretical analysis and simulation results.
文摘Saleh等在期刊Journal of Applied Mathematics and Computing的第56卷第1期上发表论文“On complementary dual qusai-twist codes”[20],证明了拟扭转码在一定条件下是线性补对偶码(LCD码)。对其中的四个关键性定理进行修正与完善,进一步给出拟扭转码是LCD的充分条件,并由此构造出许多具有优良参数的LCD码。
基金Project supported by the National Natural Science Foundation of China (Nos. 61001110,60773074,and 60903004)the China Post-doctoral Science Foundation (No. 20100470204)+1 种基金the Beijing Municipal Natural Science Foundation (No. 4082020)the National High-Tech R & D Program of China (Nos. 2007AA01Z213 and 2009AA01Z209)
文摘A general construction of inter-group complementary (IGC) codes is proposed based on perfect complementary (PC) codes,interleaving operation,and the orthogonal matrix.The correlation properties of the newly constructed IGC codes can be described as follows:(1) the autocorrelation sidelobes of the codes are zeros in the zero correlation zone (ZCZ);(2) the cross-correlation functions (CCFs) between any two different codes of the same group are zeros in the ZCZ;(3) the CCFs between any two codes of different groups are zeros everywhere.The key point of this construction is that the ZCZ length of the generated IGC codes can be chosen flexibly.It is well known that there is a limitation between the ZCZ length and the number of mates;that is,the smaller is the length of ZCZ,the more are the IGC codes that can be generated.Therefore,if we can choose the ZCZ length of the IGC codes flexibly according to the requirement of the system,more users can be accommodated in the system.
