In this paper,we numerically study chaotic synchronization communication system based on incoherent optical feedback and incoherent optical injection.The characteristics of the system,such as synchronization time,sync...In this paper,we numerically study chaotic synchronization communication system based on incoherent optical feedback and incoherent optical injection.The characteristics of the system,such as synchronization time,synchronization error,chaos shift keying encoding/decoding and modulation rate are analyzed.The results of simulation show that the system has good synchronization quality and good abilities of robust secure.The synchronization time is 1ns and the chaos shift keying encoding can reach a high rate of 1 Gbit/s.The system has a good ability of robust secure.It proves the feasibility of the optical secure communication.展开更多
In this letter,a kind of associated synchronization algorithm which is suitable for HF(High Frequency) broadband OFDM(Orthogonal Frequency Division Multiplexing) system is presented based on describing and constructin...In this letter,a kind of associated synchronization algorithm which is suitable for HF(High Frequency) broadband OFDM(Orthogonal Frequency Division Multiplexing) system is presented based on describing and constructing the GMW(Gorden,Mills and Welch) sequence. The algorithm is based on the Schmidl and Minn's symbol timing principle,the constructed GMW sequence is trans-mitted and disposed,and the synchronization is adjudicated using the correlation of GMW sequence. The simulation result indicates that this algorithm has high performance synchronization ability under the low SNR(Signal to Noise Ratio) at two different kinds of channel models.展开更多
A novel digital secure communication system employing dual synchronization of chaos in two pairs of Colpitts circuits is proposed. The binary information to be transmitted is firstly modulated by digital modulation sc...A novel digital secure communication system employing dual synchronization of chaos in two pairs of Colpitts circuits is proposed. The binary information to be transmitted is firstly modulated by digital modulation scheme, and then mixed together with two chaotic waveforms generated by two Colpitts circuits with different circuit parameters. Thus the combined (and encrypted) signal is transmitted through an additive white Gauss noise (AWGN) channel. In the receiver, the binary message can he recovered only when the parameters of the two Colpitts circuits are known. If the parameters of the two Colpitts circuits are owned by two different users, this can be viewed as a (2,2) threshold scheme. Based on large amount of simulations, the bit error rate (BER) performance of this communication scheme is presented.展开更多
In a quasi-synchronous code division multiple access(QS-CDMA) system, the correlation functions around the origin influence the system performance and odd functions are as important as the even functions. Three kinds ...In a quasi-synchronous code division multiple access(QS-CDMA) system, the correlation functions around the origin influence the system performance and odd functions are as important as the even functions. Three kinds of zero correlation zone(ZCZ) sequences are used to analyze and compare the correlation functions. Binary phase shift keying(BPSK) simulations of QS-CDMA system with the three kinds of QS sequences as spreading codes on additive white Gaussian noise(AWGN) channel show that these sequences are quasi-orthogonal, so they are suitable for QS-CDMA system. The correlation between the system performance and the zero correlation zone of the sequence is also proved.展开更多
Low correlation zone (LCZ) sequences are useful in quasi-synchronous code-division multiple access (QS-CDMA) communication systems. In this paper, a generic construction of LCZ sequences based on inter-leaved techniqu...Low correlation zone (LCZ) sequences are useful in quasi-synchronous code-division multiple access (QS-CDMA) communication systems. In this paper, a generic construction of LCZ sequences based on inter-leaved technique is investigated. Firstly, the shift sequence is shown to correspond to two-tuple balanced d-form function essentially, which results in new shift sequence. Secondly, an optimal design of p2-ary sequences over the integer residue class ring Zp2 is proposed, which improves the previous construction when p is an odd prime.展开更多
基金Supported by Shanghai Leading Academic Discipline Project ,Pro-ject Number :T0501
文摘In this paper,we numerically study chaotic synchronization communication system based on incoherent optical feedback and incoherent optical injection.The characteristics of the system,such as synchronization time,synchronization error,chaos shift keying encoding/decoding and modulation rate are analyzed.The results of simulation show that the system has good synchronization quality and good abilities of robust secure.The synchronization time is 1ns and the chaos shift keying encoding can reach a high rate of 1 Gbit/s.The system has a good ability of robust secure.It proves the feasibility of the optical secure communication.
文摘In this letter,a kind of associated synchronization algorithm which is suitable for HF(High Frequency) broadband OFDM(Orthogonal Frequency Division Multiplexing) system is presented based on describing and constructing the GMW(Gorden,Mills and Welch) sequence. The algorithm is based on the Schmidl and Minn's symbol timing principle,the constructed GMW sequence is trans-mitted and disposed,and the synchronization is adjudicated using the correlation of GMW sequence. The simulation result indicates that this algorithm has high performance synchronization ability under the low SNR(Signal to Noise Ratio) at two different kinds of channel models.
文摘A novel digital secure communication system employing dual synchronization of chaos in two pairs of Colpitts circuits is proposed. The binary information to be transmitted is firstly modulated by digital modulation scheme, and then mixed together with two chaotic waveforms generated by two Colpitts circuits with different circuit parameters. Thus the combined (and encrypted) signal is transmitted through an additive white Gauss noise (AWGN) channel. In the receiver, the binary message can he recovered only when the parameters of the two Colpitts circuits are known. If the parameters of the two Colpitts circuits are owned by two different users, this can be viewed as a (2,2) threshold scheme. Based on large amount of simulations, the bit error rate (BER) performance of this communication scheme is presented.
基金National Natural Science Foundation of China(60502016)
文摘In a quasi-synchronous code division multiple access(QS-CDMA) system, the correlation functions around the origin influence the system performance and odd functions are as important as the even functions. Three kinds of zero correlation zone(ZCZ) sequences are used to analyze and compare the correlation functions. Binary phase shift keying(BPSK) simulations of QS-CDMA system with the three kinds of QS sequences as spreading codes on additive white Gaussian noise(AWGN) channel show that these sequences are quasi-orthogonal, so they are suitable for QS-CDMA system. The correlation between the system performance and the zero correlation zone of the sequence is also proved.
基金supported by the Key grant Project of Chinese Ministry of Education(Grant No.311031)the Innovative Research Team of Sichuan Province(Grant No.2011JTD0007)+1 种基金National Natural Science Foundation of China(Grant No.91218301)the Ministry of Education of Humanities and Social Science Foundation of China(Grant No.11XJCZH002)
文摘Low correlation zone (LCZ) sequences are useful in quasi-synchronous code-division multiple access (QS-CDMA) communication systems. In this paper, a generic construction of LCZ sequences based on inter-leaved technique is investigated. Firstly, the shift sequence is shown to correspond to two-tuple balanced d-form function essentially, which results in new shift sequence. Secondly, an optimal design of p2-ary sequences over the integer residue class ring Zp2 is proposed, which improves the previous construction when p is an odd prime.