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Journal of Medical Colleges of PLA(China) 1989年第2期4卷 181-185,187页

作者：杨静华项秉懿陈南春陈苏民 Department of Biochemistry Fourth Military Medical UniversityXi'an

Eight oligonucleotide fragments were designed with the aid of a computer and synthesizedaccording to the amino add sequcnce of human atrial natriuretic factor(ANF).By means of an-nealing and ligation,these fragments were assembled into an overlapping concatenator consisting oftwo ANF genes ligated by TGATG for termination and initiation of *** was omserted into plasmid pRC23 and the recobinant DNA was transformed into *** strain *** by restriction enzyme mapping,hybridization and DNA sequenongshowed that the orientation and reading frame of the gene were correct.

关键词： atrial natriuretic factor plasmid DNA synthesis overlapping concatenated gene

Performance Evaluation of OFDM Coding System Using concatenated BCH and LDPC Codes

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International Journal of Communications, Network and System Sciences 2017年第5期10卷 67-77页

作者： H. Gagan R. Manas N. G. Girish Kumar Department of Electronics and Communication Bangalore Institute of Technology Bengaluru India Bangalore Institute of Technology Bengaluru India

This paper establishes a resilient concatenated coding platform for Orthogonal Frequency Division Multiplexing (OFDM) with Quadrature Amplitude Modulation (QAM) over Additive White Gaussian Noise (AWGN) channel. At the Forward Error Correction (FEC) coding unit, our proposed concatenated coding scheme utilizes standard type of BCH as external coding and LDPC as inner coding. In this scheme, Interleaver inclusion is seen as a catalyst to enhance the systems performance.

关键词： concatenated Codes OFDM LDPC BCH Interleaver

Logic Bell state concentration with parity check measurement

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Frontiers of physics 2019年第2期14卷 1-11页

作者： Jiu Liu Lan Zhou Wei Zhong Yu-Bo Sheng Institute of Quantum Information and Technology Nanjing University of Posts and TelecommunicationsNanjing 210003China School of Science Nanjing University of Posts and TelecommunicationsNanjing 210003China Key Lab of Broadband Wireless Communication and Sensor Network Technology (Ministry of Education) Nanjing University of Posts and TelecommunicationsNanjing 210003China

Logic qubit plays an important role in current quantum communication. In this paper, we propose an efficient entanglement concentration protocol (ECP) for a new kind of logic Bell state, where the logic qubit is the concatenated Greenber- Horne- Zeilinger (C-GHZ) state. Our ECP relies on the nondemolition polarization parity check (PPC) gates constructed with cross-Kerr nonlinearity, and can distill one pair of maximally entangled logic Bell state from two same pairs of less-entangled logic Bell states. Benefit from the nondemolition PPC gates, the concentrated maximally entangled logic Bell st ate can be remained for further application. Moreover, our ECP can be rcpea ted to further concentrate the less-entangled logic Bell state. By repeating the ECP. the total success probability can be effectively increased. Based on above features, this ECP may be useful in future long-distance quantum communication.

关键词： concatenated Greenber-Horne-Zeilinger (C-GHZ) state single photon cross-Kerr nonlinearity

Asymptotic bound on binary self-orthogonal codes

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Science China Mathematics 2009年第4期52卷 631-638页

作者： DING Yang Department of Mathematics, Southeast University, Nanjing 210096, China Department of Mathematics Southeast University Nanjing China

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.

关键词： algebraic geometry codes concatenated codes Gilbert-Varshamov bound Reed- Muller codes self-dual basis self-orthogonal codes

Turbo Coded OFDM with Large Number of Subcarriers

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Journal of Signal and Information Processing 2012年第2期3卷 161-168页

作者： Spyridon K. Chronopoulos Giorgos Tatsis Panos Kostarakis Physics Department University of Ioannina Ioannina Greece

Wireless communication systems have greatly advanced during the last years. A significant contributor in these systems’ performance has been Orthogonal Frequency Division Multiplexing (OFDM). Since its invention, it is considered to be a technological leap. This leap in splitting an information stream in multiple frequency carriers has been adapted by various scientists working on the development of wireless systems. Moreover, as OFDM presented excellent tolerance of channel fading and noise signals, the evolvement in terms of speed and reliability was consequent, because only a small stream of information is lost due to noise effects. OFDM along with the knowledge that Turbo codes is another excellent scheme of reducing BER, has triggered us to expand our research. So, we experimented in simulation level not only in joining OFDM with Turbo Codes but even in finding a better Turbo scheme compared to a typical PCCC, SCCC and a Convolutional encoder with Viterbi decoder. As the last goal has already been accomplished, in this paper is presented the new OFDM system consisted of our Turbo scheme. The analysis of the previous system took into consideration the effects of an AWGN channel. Also, this noise analysis was conducted using a simulation platform with specific attributes such as transmitting and receiving fixed number of subcarriers (2048 carriers after IFFT block) while using different types of convolutional concatenated codes, such as PCCC (Parallel), SCCC (Serial) and the new PCCC scheme. The results clearly show not only the improvement in the BER performance of the Turbo Coded OFDM systems (compared to others consisted of Viterbi decoders) but the overall superiority of the proposed design.

关键词： Orthogonal Frequency Division Multiplexing Cyclic Prefix Zero Padding Turbo Codes Parallel Convolutional concatenated Codes Serial Convolutional concatenated Codes Iterative Decoding Noise Variance

Reducing Peak-to-Average Power Ratio of a Turbo Coded OFDM

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Wireless Engineering and Technology 2012年第4期3卷 195-202页

作者： Spyridon K. Chronopoulos Vasilis Christofilakis Giorgos Tatsis Panos Kostarakis Physics Department University of Ioannina Ioannina Greece

Peak to Average Power Ratio (PAPR) is defined as the instantaneous power (maximum value) to the average power ratio. PAPR is considered to be a major problem in OFDM systems. This problem can cause radical unexpected behavior of the signal fluctuation. This fluctuation is constituted by a large number of power states. The enormous number of these states leads to an additional complexity of ADCs and DACs. This research addresses the previous problem in OFDM systems utilizing Turbo Codes. μLaCP technique is employed for the purpose of decreasing PAPR. Moreover, our OFDM system was simulated in the presence of an AWGN channel with four types of codes (without the presence of ADCs and DACs). These were constituted of PCCC (typical and new), SCCC, and Convolutional Codes. Our Turbo Coded OFDM exhibited unchanged BER performance before and after the use of μLaCP technique. This was accomplished by modifying our previous PAPR reduction technique without sacrificing greatly its attributes.

关键词： Orthogonal Frequency Division Multiplexing Peak to Average Power Ratio μ-Law μLaCP μLaIF Parallel concatenated Convolutional Codes A Posteriori Probability Cyclic Prefix Zero Padding Peak Ratio Bit Error Rate