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Sarve:synthetic data and local differential privacy for private frequency estimation

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Cybersecurity 2022年第4期5卷 97-116页

作者： Gatha Varmal Ritu Chauhan Dhananjay Singh Amity Institute of Information Technology Amity UniversityNoidaIndia Center for Computational Biology and Bioinformatics Amity UniversityNoidaIndia Department of Electronics Engineering HUFSSeoulKorea

The collection of user attributes by service providers is a double-edged sword.They are instrumental in driving statistical analysis to train more accurate predictive models like recommenders.The analysis of the collected user data includes frequency estimation for categorical attributes.Nonetheless,the users deserve privacy guarantees against inadvertent identity disclosures.Therefore algorithms called frequency oracles were developed to randomize or perturb user attributes and estimate the frequencies of their values.We propose Sarve,a frequency oracle that used Randomized Aggregatable Privacy-Preserving Ordinal Response(RAPPOR)and Hadamard Response(HR)for randomization in combination with fake data.The design of a service-oriented architecture must consider two types of complexities,namely computational and communication.The functions of such systems aim to minimize the two complexities and therefore,the choice of privacy-enhancing methods must be a calculated decision.The variant of RAPPOR we had used was realized through bloom flters.A bloom filter is a memory-efficient data structure that offers time complexity of O(1).On the other hand,HR has been proven to give the best communication costs of the order of log(b)for b-bits communication.Therefore,Sarve is a step towards frequency oracles that exhibit how privacy provisions of existing methods can be combined with those of fake data to achieve statistical results comparable to the original data.Sarve also implemented an adaptive solution enhanced from the work of Arcolezi et al.The use of RAPPOR was found to provide better privacy-utility tradeoffs for specific privacy budgets in both high and general privacyregimes.

关键词： Synthetic data Differential privacy frequency estimation frequency oracle Privacy

Robust frequency estimation Under Additive Mixture Noise

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Computers, Materials & Continua 2022年第7期72卷 1671-1684页

作者： Yuan Chen Yulu Tian Dingfan Zhang Longting Huang Jingxin Xu School of Computer and Communication Engineering University of Science&Technology BeijingBeijing100083China School of Automation Science and Electrical Engineering Beihang UniversityBeijing100191China School of Information Engineering Wuhan University of TechnologyWuhan430070China Department of Energy and Public Works Queensland4702Australia

In many applications such as multiuser radar communications and astrophysical imaging processing,the encountered noise is usually described by the finite sum ofα-stable(1≤αfrequency estimator is devised by employing the Metropolis-Hastings(M-H)algorithm.Meanwhile,to guarantee the fast convergence of the M-H chain,a new proposal covariance criterion is also devised,where the batch of previous samples are utilized to iteratively update the proposal covariance in each sampling process.Computer simulations are carried out to indicate the superiority of the developed scheme,when compared with several conventional estimators and the Cramér-Rao lower bound.

关键词： frequency estimation additive cauchy-gaussian noise voigt profile metropolis-hastings algorithm cramér-rao lower bound

Visible Light Indoor Positioning System Based on Pisarenko Harmonic Decomposition and Neural Network

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Chinese Journal of Electronics 2024年第1期33卷 195-203页

作者： Li ZHAO Yi REN Qi WANG Lange DENG Feng ZHANG School of Electronic Information Engineering Xi’an Technological University

Visible-light indoor positioning is a new generation of positioning technology that can be integrated into smart lighting and optical communications. The current received signal strength(RSS)-based visible-light positioning systems struggle to overcome the interferences of background and indoor-reflected noise. Meanwhile, when ensuring the lighting, it is impossible to use the superposition of each light source to accurately distinguish light source information; furthermore, it is difficult to achieve accurate positioning in complex indoor environments. This study proposes an indoor positioning method based on a combination of power spectral density detection and a neural network. The system integrates the mechanism for visible-light radiation detection with RSS theory, to build a back propagation neural network model fitting for multiple reflection channels. Different frequency signals are loaded to different light sources at the beacon end, and the characteristic frequency and power vectors are obtained at the location end using the Pisarenko harmonic decomposition method. Then, a complete fingerprint database is established to train the neural network model and conduct location tests. Finally, the location effectiveness of the proposed algorithm is verified via actual positioning experiments. The simulation results show that, when four groups of sinusoidal waves with different frequencies are superimposed with white noise, the maximum frequency error is 0.104 Hz and the maximum power error is 0.0362 W. For the measured positioning stage, a 0.8 m × 0.8 m × 0.8 m solid wood stereoscopic positioning model is constructed, and the average error is 4.28 cm. This study provides an effective method for separating multi-source signal energies, overcoming background noise, and improving indoor visible-light positioning accuracies.

关键词： Visible-light communication Indoor positioning frequency estimation Pisarenko harmonic decomposition Back propagation neural network

KSKV:Key-Strategy for Key-Value Data Collection with Local Differential Privacy

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Computer Modeling in Engineering & Sciences 2024年第6期139卷 3063-3083页

作者： Dan Zhao Yang You Chuanwen Luo Ting Chen Yang Liu Artificial Intelligence Development Research Center Institute of Scientific and Technical Information of ChinaBeijing100038China Industry Development Department NSFOCUS Inc.BeijingChina School of Information Science and Technology Beijing Forestry UniversityBeijing100083China School of Computer Science and Engineering University of Electronic Science and Technology of ChinaChengdu610054China Institute of Computing Technology China Academy of Railway Sciences Corporation LimitedBeijing10081China

In recent years,the research field of data collection under local differential privacy(LDP)has expanded its focus fromelementary data types to includemore complex structural data,such as set-value and graph data.However,our comprehensive review of existing literature reveals that there needs to be more studies that engage with key-value data collection.Such studies would simultaneously collect the frequencies of keys and the mean of values associated with each key.Additionally,the allocation of the privacy budget between the frequencies of keys and the means of values for each key does not yield an optimal utility tradeoff.Recognizing the importance of obtaining accurate key frequencies and mean estimations for key-value data collection,this paper presents a novel framework:the Key-Strategy Framework forKey-ValueDataCollection under LDP.Initially,theKey-StrategyUnary Encoding(KS-UE)strategy is proposed within non-interactive frameworks for the purpose of privacy budget allocation to achieve precise key frequencies;subsequently,the Key-Strategy Generalized Randomized Response(KS-GRR)strategy is introduced for interactive frameworks to enhance the efficiency of collecting frequent keys through group-anditeration methods.Both strategies are adapted for scenarios in which users possess either a single or multiple key-value pairs.Theoretically,we demonstrate that the variance of KS-UE is lower than that of existing methods.These claims are substantiated through extensive experimental evaluation on real-world datasets,confirming the effectiveness and efficiency of the KS-UE and KS-GRR strategies.

关键词： Key-value local differential privacy frequency estimation mean estimation data perturbation

Flexible and Accurate frequency estimation for Complex Sinusoid Signal by Interpolation Using DFT Samples

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Chinese Journal of Electronics 2018年第1期27卷 109-114页

作者： XIANG Jinzhi CUI Wei SHEN Qing School of Information and Electronics Beijing Institute of Technology

A flexible and accurate frequency estimator is first proposed for frequency estimation of a complex sinusoid weighted with a rectangular window function in additive white Gaussian noise. This proposed frequency estimator can be operated in the application of an arbitrary length discrete Fourier transform where the original input data is padded with any zeroes, which makes it more flexible in practice. The proposed frequency estimator utilizes the maximum sample value and its two adjacent samples in the frequency domain to perform the fine frequency estimation with unbiased results obtained. Then a modified frequency estimator is proposed to estimate the frequency when the complex sinusoid signal is weighted with different nonrectangular window functions. Although the modified frequency estimator is nonanalytic and biased, it can still improve the estimation performance for certain applications. Simulation results demonstrate that both of the proposed frequency estimators are effective to achieve the high frequency estimation accuracy. And the root mean square errors of the proposed frequency estimators approach the Cramer-Rao bound when the signal-to-noise ratio is large enough to make the coarse frequency estimation work effectively.

关键词： frequency estimation Complex sinusoid DFT interpolation Zero-padding

Enhanced fourth-power algorithm for phase estimation with frequency separation in direct-detection optical OFDM systems

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Chinese Optics Letters 2013年第6期11卷 10-15页

作者：孔敏肖江南董泽杨柳青青陈林余建军 Key Laboratory for Micro-/Nano-Optoelectronic Devices of Ministry of EducationDepartment of Information Science and EngineeringHunan University ZTE USA MorristownNJ 07960USA Fudan University

The optical orthogonal frequency division multiplexing （OFDM） signal is affected by impairments intro- duced by electrical filters and optical chromatic dispersion. An enhanced fourth-power algorithm for phase estimation with frequency separation is used to estimate and compensate the phase rotation of OFDM subcarriers. The performance of the proposed phase estimation algorithm is evaluated on a 4-Gb/s OFDM signal at different frequencies. Experimental results using the proposed algorithm show a 1.8-dB received power sensitivity improvement at a bit error rate of 1 × 10^-4 after a 100-kin standard single-mode fiber transmission, compared with the conventional technique.

关键词： Algorithms Chromatic dispersion estimation frequency estimation Single mode fibers Telecommunication systems

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frequency and Offset Online estimation of Sinusoidal Signals Based on High-Order Nonlinear Continuous Differentiator

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Chinese Journal of Electronics 2017年第3期26卷 579-584页

作者： WANG Hongwei ZHANG Wei ZUO Junyi WANG Heping School of Aeronautics Northwestern Polytechnical University

Real-time parameter identification of sinusoidal signals is an essential research topic due to its broad utilization in both theoretical studies and engineering practice.A tracking differentiator based online estimation framework has been proposed to simultaneously identify frequencies and offset of given multi-sinusoidal signal.Tracking differentiator is exploited in presented framework to track the time derivatives of measurements which are then utilized to estimate the frequencies and offset.We introduce a tracking differentiator called high-order nonlinear continuous differentiator into the framework,giving birth to a new estimation algorithm.Comparative experiments on both single and two sinusoidal signal are simulated,indicating the superiority of proposed method on both convergent speed and estimation accuracy.

关键词： frequency estimation Offset estimation High-order nonlinear continuous differentiator Sinusoidal signal Multi-sinusoidal signal

Joint estimation of frequency offset and chromatic dispersion based on the training sequences in M-ary QAM coherent optical transmission system

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Chinese Optics Letters 2014年第10期12卷 27-30页

作者：孙艺萍席丽霞唐先锋赵东鹤乔耀军张霞张晓光 State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and Telecommunications The Key Laboratory of Optical Communications Science & Technology in Shandong Province Liaocheng University

A data-aided method of joint frequency offset and chromatic dispersion estimation based on the Chu training sequences is shown in 112 Gb/s polarization-multiplexed （PM） quadrature phase-shift keying and 224 Gb/s PM-16-quadrature amplitude modulation with different pulse-shaping filters, respectively. The proposed method achieves a good accuracy and is verified to be robust to polarization mode dispersion.

关键词： Amplitude modulation Chromatic dispersion Dispersions frequency allocation frequency estimation Optical systems Phase shift Phase shifters Polarization Polarization mode dispersion Pulse shaping Quadrature amplitude modulation Quadrature phase shift keying Signal encoding

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STUDY ON frequency estimation BASED ON WEIGHTED LEAST SQUARE METHOD WITH THREE FOURIER COEFFICIENTS

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Journal of Electronics(China) 2013年第5期30卷 430-435页

作者： Ren Chunhui Fu Yusheng School of Electronic Engineering University of Electronic Science and Technology of China Institute of Aeronautic Science and Technology University of Electronic Science and Technology of China

In this paper,a sinusoidal signal frequency estimation algorithm is proposed by weighted least square method.Based on the idea of Provencher,three biggest Fourier coefficients in the maximum periodogram are considered,the Fourier coefficients can be written as three equations about the amplitude,phase,and frequency,and the frequency is estimated by solving equations.Because of the error of measurement,weighted least square method is used to solve the frequency equation and get the signal frequency.It is shown that the proposed estimator can approach the Cramer-Rao Bound(CRB)with a low Signal-to-Noise Ratio(SNR)threshold and has a higher accuracy.

关键词： Sinusoidal signal frequency estimation Fourier coefficients Weighted least square method

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