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The Adaptive Multi-Level phase coding Method in Audio Steganography

IEEE ACCESS 2019年 7卷 129291-129306页

作者： Alsabhany, Ahmed Abduljabbar Ridzuan, Farida Azni, A. H. USIM FST Nilai 71800 Malaysia USIM ISI CyberSecur & Syst Res Unit Nilai 71800 Malaysia

Audio steganography allows and inspires many researchers to design methods for secure communication. Based on the evaluation on the existing methods, it was found that most methods focused on one or two requirements while disregarding others, causing imbalanced performance. Moreover, most methods lack adaptivity and dynamic allocation. Therefore, in this research, a method called Adaptive Multi-level phase coding (AMPC) was proposed to optimize the above issues. The reverse logic of the main tradeoffs was used to empirically design several embedding levels that that simultaneously attained good performance for all aspects as much as possible. Then, an adaptive component was added by selecting the embedding level that provided the best performance for each embedding process. Moreover, the error spreading factor was introduced to achieve a fair payload distribution. The performance balance objective requires a new formulation that will enable the accurate selection of the degree of modification, multiple-bit embedding per modification, and reduced retrieval errors. As a result, the interval centering quantization (ICQ) was formulated and implemented in the proposed method. The experimental results show that AMPC successfully fulfilled the research objectives. Also, AMPC surpassed other phase coding methods in all aspects while time-domain methods achieved the highest transparency and capacity with the lowest robustness. Moreover, experiments show that the implementation of adaptive multi-level concept is able to improve the existing method's performance significantly. In summary, AMPC was able to achieve a stable embedding rate of 33 Kbps at 35 dB of SNR, which is higher than the recorded embedding rate of other phase coding methods.

关键词： Audio steganography phase coding adaptive multi-level AMPC LSB

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Inherent security of phase coding quantum key distribution systems against detector blinding attacks

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LASER PHYSICS LETTERS 2018年第9期15卷

作者： Balygin, K. A. Klimov, A. N. Bobrov, B. Kravtsov, K. S. Kulik, S. P. Molotkov, S. N. Moscow MV Lomonosov State Univ Fac Phys Moscow 119991 Russia Russian Acad Sci Prokhorov Gen Phys Inst Moscow 119991 Russia Moscow MV Lomonosov State Univ Quantum Technol Ctr Moscow 119991 Russia Acad Cryptog Russian Federat Moscow 121552 Russia Russian Acad Sci Inst Solid State Phys Chernogolovka 142432 Moscow Region Russia Moscow MV Lomonosov State Univ Fac Computat Math & Cybernet Moscow 119991 Russia

An attack exploiting single-photon avalanche diode (SPAD) blinding is one of the effective methods of 'quantum hacking' (Lydersen et al 2010 Nat. Photon. 4 686) or cracking quantum key distribution (QKD) systems. This attack was experimentally demonstrated for various QKD systems based on both phase and polarization coding. After such an attack, the eavesdropper knows the whole key, has not produced errors, and is not detected. So far this attack is the only one that was demonstrated in the explicit form on many real QKD systems. It is important that these demonstrations were actually performed in reality, i.e. not in speculations as some other attacks. Therefore, the presence of vulnerability in QKD systems based on polarization coding is an existing fact, rather than just a potential threat. It is often assumed that all systems regardless of the encoding method are vulnerable to such an attack. However, in the case of phase coding, some essential features of photocount statistics on the receiving side make a difference. In this Letter we prove that detector blinding attack, when acts on QKD systems with phase coding, leads to a distortion of the photocounts statistics so the eavesdropper may always be detected. Moreover, one does not need to change the design of the QKD system and/or its control electronics, as it is sufficient to amend only the processing of the quantum states registration results to make the system secure. At the same time, polarization coding-based systems remain vulnerable to such an attack and do not guarantee key security.

关键词： quantum cryptography detector blinding attacks phase coding

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Enhanced phase-coding method for three-dimensional shape measurement with half-period codeword

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APPLIED OPTICS 2019年第27期58卷 7359-7366页

作者： Wang, Yuwei Liu, Lu Wu, Jun Chen, Xiangcheng Wang, Yajun Anhui Agr Univ Coll Engn Hefei 230036 Anhui Peoples R China Wuhan Univ Technol Sch Automat Wuhan 430070 Hubei Peoples R China Wuhan Univ State Key Lab Informat Engn Surveying Mapping & R Wuhan 430079 Hubei Peoples R China

The phase-coding method has been widely used for 3D shape measurement, which uses sinusoidal phase-shifting patterns to recover the wrapped phase and the stair phase-coding patterns to determine the fringe order. However, due to random noises and image blurring, the fringe order is always misaligned with the wrapped phase, which will lead to fringe order errors. This paper presents an enhanced phase-coding method to address this misalignment problem by using half-period codewords, in which each codeword is aligned to the half-period of the sinusoidal patterns. Then, two complementary fringe orders with half-period dislocation can be calculated, which can effectively eliminate the fringe order errors. To extend the coding range of stair phase, this paper further develops a computational scheme based on the geometric constraint method. Simulations and experiments have been carried out, and their results confirm that the enhanced method can reliably recover the 3D shape of the measured objects. (C) 2019 Optical Society of America

关键词： 3D shape measurement image blur interference pattern phase coding codeword random noise Half Life fringe order computational scheme shape measurement

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Decoy state method for quantum cryptography based on phase coding into faint laser pulses

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LASER PHYSICS LETTERS 2017年第12期14卷

作者： Kulik, S. P. Molotkov, S. N. Moscow MV Lomonosov State Univ Fac Phys Moscow Russia Acad Cryptog Russian Federat Moscow 121552 Russia Russian Acad Sci Inst Solid State Phys Chernogolovka 142432 Moscow Distr Russia Moscow MV Lomonosov State Univ Fac Computat Math & Cybernet Moscow Russia

We discuss the photon number splitting attack (PNS) in systems of quantum cryptography with phase coding. It is shown that this attack, as well as the structural equations for the PNS attack for phase encoding, differs physically from the analogous attack applied to the polarization coding. As far as we know, in practice, in all works to date processing of experimental data has been done for phase coding, but using formulas for polarization coding. This can lead to inadequate results for the length of the secret key. These calculations are important for the correct interpretation of the results, especially if it concerns the criterion of secrecy in quantum cryptography.

关键词： quantum key distribution PNS measurements phase coding decoy state

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Mechanosensory-Based phase coding of Odor Identity in the Olfactory Bulb

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NEURON 2017年第5期96卷 1139-+页

作者： Iwata, Ryo Kiyonari, Hiroshi Imai, Takeshi RIKEN Lab Sensory Circuit Format Ctr Dev Biol Kobe Hyogo 6500047 Japan RIKEN Ctr Life Sci Technol Anim Resource Dev Unit Kobe Hyogo 6500047 Japan RIKEN Ctr Life Sci Technol Genet Engn Team Kobe Hyogo 6500047 Japan Japan Sci & Technol Agcy JST PRESTO Kawaguchi Saitama 3320012 Japan Kyoto Univ Grad Sch Biostudies Kyoto 6068501 Japan Kyushu Univ Grad Sch Med Sci Fukuoka 8128582 Japan

Mitral and tufted (M/T) cells in the olfactory bulb produce rich temporal patterns of activity in response to different odors. However, it remains unknown how these temporal patterns are generated and how they are utilized in olfaction. Here we show that temporal patterning effectively discriminates between the two sensory modalities detected by olfactory sensory neurons (OSNs): odor and airflow-driven mechanical signals. Sniff-induced mechanosensation generates glomerulus-specific oscillatory activity in M/T cells, whose phase was invariant across airflow speed. In contrast, odor stimulation caused phase shifts (phase coding). We also found that odor-evoked phase shifts are concentration invariant and stable across multiple sniff cycles, contrary to the labile nature of rate coding. The loss of oscillatory mechanosensation impaired the precision and stability of phase coding, demonstrating its role in olfaction. We propose that phase, not rate, coding is a robust encoding strategy of odor identity and is ensured by airflow-induced mechanosensation in OSNs.

关键词： olfaction temporal coding phase coding sniffing mechanosensation oscillations concentration invariance olfactory sensory neurons mitral/tufted cells olfactory bulb

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Comparison of radar waveforms combining pseudo-random binary phase coding and chirp modulation for an high-frequency monostatic radar

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IET RADAR SONAR AND NAVIGATION 2016年第5期10卷 935-944页

作者： Shi, Shu-zhu Zhao, Zheng-yu Liu, Jing-nan Wuhan Univ Res Ctr Global Nav Satellite Syst Wuhan 430079 Peoples R China Wuhan Univ Sch Elect Informat Wuhan 430072 Peoples R China

Wuhan ionospheric oblique backscattering sounding system (WIOBSS) is a low-power high-frequency monostatic radar used for ionospheric sensing and aircraft detection. In this study, a novel waveform combining the pseudo-random binary phase coding (PRBPC) and the chirp modulation is proposed for this radar. Furthermore, in terms of the radar waveform requirements, four subclasses of this waveform are theoretically compared to determine which one of them is most suitable for WIOBSS, including the inter-pulse PRBPC waveform where the width of the subpulse is equal to the chirp duration, the inter-pulse PRBPC waveform where the period of the coding sequence is equal to the chirp duration, the intra-pulse PRBPC waveform where the width of the subpulse is equal to the chirp duration, and the intra-pulse PRBPC waveform where the period of the coding sequence is equal to the chirp duration. The radar waveform requirements, the ambiguity function analysis, and the performance comparison of aforementioned waveforms are described. The analysis results show that the inter-pulse PRBPC waveform where the period of the coding sequence is equal to the chirp duration has the best performance, and can achieve higher range resolution, larger signal processing gain, and better Doppler tolerance than the conventional binary phase coded waveforms.

关键词： binary codes phase coding ionospheric techniques backscatter chirp modulation Doppler radar radar resolution radar waveform requirements pseudo-random binary phase coding chirp modulation low-power high-frequency monostatic radar Wuhan ionospheric oblique backscattering sounding system WIOBSS ionospheric sensing aircraft detection interpulse PRBPC waveform coding sequence period intrapulse PRBPC waveform ambiguity function analysis range resolution signal processing gain Doppler tolerance

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A fast three-dimensional shape measurement method based on color phase coding

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OPTIK 2016年第3期127卷 1011-1015页

作者： Li, Biao Fu, Yanjun Zhang, Jiancheng Wu, Haitao Xia, Guisuo Jiang, Guangyu Nanchang Hangkong Univ Minist Educ Key Lab Nondestruct Testing Nanchang 330063 Peoples R China

Gray code plus phase-shifting method embed the codeword into intensity to reconstruct complex three-dimensional shape. Owing to surface reflectivity and noise, it is less robust for measuring the surfaces of object with low contrast. In order to solve the problem, the codeword is embedded into phase to determine fringe order for obtaining the unwrapped phase. However, measurement speed is limited. Therefore, a fast three-dimensional shape measurement method based on color phase coding is proposed. As it adopts a color sinusoidal fringe to obtain wrapped phase and an additional color phase coding fringe to determine fringe order, the method can achieve fast complex three-dimensional shape measurement with different contrast. Color crosstalk and gamma nonlinearity are compensated to improve the measurement accuracy. The experiment results confirm the effectiveness and robustness of the proposed method. (C) 2015 Elsevier GmbH. All rights reserved.

关键词： Three-dimensional shape measurement phase-shifting method phase coding Color crosstalk

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Temporal coding with Magnitude-phase Regularization for Sound Event Detection 23

Temporal Coding with Magnitude-Phase Regularization for Soun...

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Interspeech Conference

作者： Park, Sangwook Kothinti, Sandeep Elhilali, Mounya Gangneung Wonju Natl Univ Dept Elect Engn Kangnung South Korea Johns Hopkins Univ Dept Elect & Comp Engn Baltimore MD 21218 USA

Sound Event Detection (SED) is the challenge of identifying sound events into their temporal boundaries as well as sound category. With recent advances in deep learning, more effective SED techniques are investigated through the annual challenge of Detection and Classification of Acoustic Scenes and Events (DCASE). Most SED systems rely on data-driven learning where a deep neural network is trained to minimize the error between model prediction and the truth. While this framework is generally effective at identifying sound classes present in an audio recording, it results in unreliable estimates of temporal information for identifying sound boundaries. In order to heighten the temporal precision, this paper proposes a novel temporal coding of magnitude and phase for embedding vectors in an intermediate layer. This coding is reflected as a regularization term in the objective function for training the model. The regularization allows magnitude of embedding vectors to increase near event boundaries, which represent the onset and offset points. Simultaneously, each of the boundaries are distinguishable from others using phase difference between two neighboring vectors. This approach results in notable improvement in timing sensitivity compared to a baseline system tested on SED task in the context of DCASE2021 challenge.

关键词： sound event detection coherence loss time balanced focal loss phase coding

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Multiple Access Applications of Transform Domain Communication System Based on phase coding 5

Multiple Access Applications of Transform Domain Communicati...

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IEEE 5th International Conference on Big Data and Cloud Computing (BDCloud)

作者： Sun, Haixin Cao, Fucheng Qin, Hongwu Changchun Univ Sch Elect & Informat Engn Changchun Peoples R China

ISBN: (纸本)9781467371834

Transform Domain Communication System (TDCS) has been proposed as a new candidate applied in the cognitive radio (CR) environment since it can avoid existing users or jammers intelligently over a given bandwidth. The TDCS achieves noise-like property and orthogonality characteristic by generating a PR phase vector through a random phase coding processing. In this paper, a new implementation of TDCS is proposed for multiple access application by using spreading sequence with phase coding for the PR phase vector generation. The analysis and simulation of the selection of spreading sequence are studied and the related parameters are discussed. The simulation results demonstrate that the proposed scheme provides good bit error rate in multiple access environments.

关键词： Transform domain communication system phase coding multiple access spreading sequence

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Robust and reliable audio watermarking based on phase coding 40

Robust and reliable audio watermarking based on phase coding

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40th IEEE International Conference on Acoustics, Speech, and Signal Processing, ICASSP 2015

作者： Ngo, Nhut Minh Unoki, Masashi School of Information Science Japan Advanced Institute of Science and Technology 1-1 Asahidai Nomi Ishikawa Japan

ISBN: (纸本)9781467369978

This paper proposes a novel robust audio watermarking method based on phase coding. The quantization index modulation technique is employed for embedding watermarks into the phase spectrum of audio signals. To increase robustness of the proposed method, the region of phase spectrum that is resistant against attacks is selected for embedding. We experimentally analyzed the phase spectrum to find out which region is not distorted under attacks. On the other hand, the quantization step size is suitably selected so that the modification of phase does not cause severe distortion in sound quality. The experimental results show that the watermarks could be kept inaudible in audio signals and robust against attacks. The proposed method has the ability to embed watermarks into audio signals up to 400 bits per second with a bit error rate of less than 1%. © 2015 IEEE.

关键词： audio watermarking phase coding quantization index modulation robustness

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