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Iterative phase noise Suppression for Full-Duplex Communication Systems

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China Communications 2023年第2期20卷 226-234页

作者： Pengxin Guan Yiru Wang Hongkang Yu Yuping Zhao School of Electronics Engineering and Computer Science Peking UniversityBeijing 100871China Wireless Product Research and Development Institute ZTE CorporationShenzhen 518057China

Oscillator phase noise is one of the bottlenecks that limits the self-interference(SI)cancellation capability of full-duplex systems.In this paper,we propose a method for the suppression of common phase error(CPE)and intercarrier interference(ICI)induced by the phase noise in full-duplex orthogonal frequency division multiplexing(OFDM)systems.First,we regard the effect of CPE as a portion of the SI channel and perform estimation,reconstruction and elimination in the time domain.Then,the ICI signal is estimated and suppressed in the frequency domain.Additionally,by analysing the performance of proposed algorithm,we further develop an iterative mechanism to reduce the parameter estimation error and improve SI cancellation capability.Simulation results show that the proposed method has a significant SI cancellation capability improvement over the traditional SI cancellation schemes.

关键词： full-duplex self-interference phase noise suppression

phase noise modeling in LC oscillators implemented in SiGe technology

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Journal of Semiconductors 2013年第2期34卷 60-66页

作者： M.Bouhouche S.Latreche C.Gontrand Universite Mentouri Faculte des Sciences de l'IngenieurDepartement d'ElectroniqueLaboratoire Hyperfrequence & Semi-conducteur(LHS)25000ConstantineAlegria Universite de Lyon VilleurbanneF-69621France

This paper addresses phase noise analysis of a radiofrequency LC oscillator built around a SiGe heterojunction bipolar transistor （HBT） realized in a 0.35 um BiCMOS process, as an active device. First, we give a brief background to SiGe HBT device physics. The key point is to initiate quantitative analysis on the influence of defects induced during extrinsic base implantation on electric performances of this device. These defects are responsible for the current fluctuations at the origin of low frequency noise in BiCMOS technologies. Next, we investigate the effect of implantation defects as a source of noise in semiconductors on the phase noise of a radiofrequency LC oscillator. We observe their influence on the oscillator phase noise, and we quantify the influence of their energy distribution in the semiconductor gap. Second, we give a behavioral model of an LC oscillator con- taining a SiGe HBT as an active device. The key goal is to study the susceptibility of a radiofrequency oscillator built around a SiGe HBT to phase noise disturbance sources. Based on the time variance behavior of phase noise in oscillators, transient simulations （in the time domain） were used to analyze the time-dependent noise sensitivity of the oscillator.

关键词： SiGe heterojunction radiofrequency mixed-mode simulations oscillator phase noise

phase noise characteristics of narrow-linewidth fiber laser and laser diode in unbalanced interferometers

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Chinese Optics Letters 2013年第2期11卷 55-57页

作者：周会娟陈伟孟洲孙崇峰 College of Opto-electronic Science and Engineering National University of Defense Technology Institute of Information Science and Engineering Henan University of Technology

The phase noises of two narrow-linewidth fiber laser and laser diode are measured by using unbalanced Michelson interferometers with various optical path differences （OPDs）. The measured results indicate that the phase noises of the two lasers do not change linearly with the OPD over the range from 1 to 100 m. The laser diode exhibits phase noise levels higher than that of the fiber laser at OPDs longer than 10 m. However, the laser diode outperforms the fiber laser at OPDs shorter than 10 m. The results obtained can assess laser performance and determine the suitable laser for use in a particular application.

关键词： Michelson interferometers phase noise

phase noise correction for OFDM signal based on DCT approach and variational inference

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The Journal of China Universities of Posts and Telecommunications 2012年第3期19卷 27-32页

作者： CHEN Peng LI Nan LI Ju-hu HE Zhi-qiang WU Wei-ling Key Laboratory of Universal Wireless Communications Ministry of EducationBeijing University of Posts and TelecommunicationsBeijing 100876China

A novel scheme to joint phase noise （PHN） correcting and channel noise variance estimating for orthogonal frequency division multiplexing （OFDM） signal was proposed, The new scheme was based on the variational Bayes （VB） method and discrete cosine transform （DCT） approximation. Compared with the least squares （LS） based scheme, the proposed scheme could overcome the over-fitting phenomenon and thus lead to an improved performance. Computer simulations showed that the proposed VB based scheme outperforms the existing LS based scheme

关键词： variational Bayes method discrete cosine transform phase noise OFDM

Joint MAP channel estimation and data detection for OFDM in presence of phase noise from free running and phase locked loop oscillator

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Digital Communications and Networks 2021年第1期7卷 55-61页

作者： Kamayani Shrivastav R.P.Yadav K.C.Jain Department of Electronics and Communication Malaviya National Institute of Technology302017India Department of Matiiematics Indian Institute of Information TechnologyKotaIndia

This paper addresses a computationally compact and statistically optimal joint Maximum a Posteriori(MAP)algorithm for channel estimation and data detection in the presence of phase noise(PHN)in iterative Orthogonal Frequency Division Multiplexing(OFDM)receivers used for high speed and high spectral efficient wireless communication systems.The MAP cost function for joint estimation and detection is derived and optimized further with the proposed cyclic gradient descent optimization algorithm.The proposed joint estimation and detection algorithm relaxes the restriction of small PHN assumptions and utilizes the prior statistical knowledge of PHN spectral components to produce a statistically optimal solution.The frequency-domain estimation of Channel Transfer Function(CTF)in frequency selective fading makes the method simpler,compared with the estimation of Channel Impulse Response(CIR)in the time domain.Two different time-varying PHN models,produced by Free Running Oscillator(FRO)and phase-Locked Loop(PLL)oscillator,are presented and compared for performance difference with proposed OFDM receiver.Simulation results for joint MAP channel estimation are compared with Cramer-Rao Lower Bound(CRLB),and the simulation results for joint MAP data detection are compared with“NO PHN"performance to demonstrate that the proposed joint MAP estimation and detection algorithm achieve near-optimum performance even under multipath channel fading.

关键词： Orthogonal frequency division multiplexing phase noise Free running oscillator phase-locked loop oscillator Maximum a posteriori Channel estimation Data detection

Cognitive anti-jamming receiver under phase noise in high frequency bands

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Journal of Systems Engineering and Electronics 2018年第1期29卷 31-38页

作者： FANG Zheng LI Haitao QIAN Yiming School of Electronic Information and Electrical EngineeringShanghai Jiao Tong UniversityShanghai 200240China China Science and Technology on Avionics Integration Laboratory Shanghai 200233China Faculty of Information Technology Beijing University of TechnologyBeijing 100124China China Nuclear Control System Engineering CO. LTDBeijing 100176China

This paper investigates the jamming sensing performance of the simultaneous transmit and receive based cognitive anti-jamming(SCAJ) receiver impaired by phase noise in local oscillators(LO) over fading channels. Firstly, energy detection(ED)based on the jamming to noise ratio(JNR) of the high frequency bands SCAJ receiver with phase noise under different channels is analyzed. Then, the probabilities of jamming detection and false alarm in closed-form for the SCAJ receiver are derived. Finally,the modified Bayesian Cramer-Rao bound(BCRB) of jamming sensing for the SCAJ receiver is presented. Simulation results show that the performance degradation of the SCAJ system due to phase noise is more severe than that due to the channel fading in the circumstances where the signal bandwidth(BW) is kept a constant. Moreover, the signal BW has an effect on the phase noise in LO, and the jamming detection probability of the wideband SCAJ receiver with lower phase noise outperforms that of the narrowband receiver using the same center frequency. Furthermore,an accurate phase noise estimation and compensation scheme can improve the jamming detection capability of the SCAJ receiver in high frequency bands and approach to the upper bound.

关键词： high frequency band simultaneous transmit and receive phase noise cognitive anti-jamming

phase noise floor suppression of the output carrier from double sideband-carrier suppressed modulation system

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Science China(Information Sciences) 2011年第6期54卷 1312-1320页

作者： LUO Xin, HAN XiuYou, GU YiYing, LI ShanFeng & ZHAO MingShan School of Physics and Optoelectronic Engineering, Dalian University of Technology, Dalian 116023, China School of Physics and Optoelectronic Engineering Dalian University of Technology Dalian China

A theoretical model of all the influencing factors on the phase noise floor of the output carrier from the double sideband-carrier suppressed (DSB-CS) modulation system is presented. Based on the established DSB-CS modulation system with different cases, the phase noise of the input carrier and the output doubled frequency carrier is measured and calculated using the theoretical model, respectively. The calculation results basically agree with the measurement results. It is shown that the phase noise floor of the output carrier is primarily influenced by the signal-spontaneous beat noise and the relative intensity noise (RIN) of the laser. So the phase noise floor of the output carrier can be minimized by choosing the laser with low RIN and the EDFA with low noise factor.

关键词： microwave photonics double sideband-carrier suppressed modulation phase noise

phase noise sensitivity analysis of lattice constellation

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The Journal of China Universities of Posts and Telecommunications 2010年第2期17卷 36-40页

作者： YU Guang-wei NIU Kai HE Zhi-qiang WANG Xu-zhen LIN Jia-ru Key Laboratory of Universal Wireless Communications Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

Based on the assumption of large number of constellation points and high signal-to-noise ratio （SNR）, phase noise sensitivity of lattice constellation is analyzed. The upper bound of symbol error rate （SER） in additive white Gaussian noise （AWGN） channel is derived from pairwise error probability. For small phase noise, phase noise channel is transformed to AWGN channel. With the aid of Wiener model, the obtained upper bound can be extended to phase noise channel. The proposed upper bound can be used as performance criterion to analyze the sensitivity of phase noise in multi-dimensional lattice constellation. Simulation results show that with the same normalized spectral efficiency, higher dimensional lattice constellations are more sensitive than lower ones in phase noise channel. It is also shown that with the same dimension of constellation, larger normalized spectral efficiency means more performance loss in phase noise channel.

关键词： lattice constellation symbol error rate （SER） phase noise

Performance analyses of OFDM AF relaying system in the presence of phase noise with APS and IPS

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The Journal of China Universities of Posts and Telecommunications 2016年第5期23卷 1-9页

作者： Huang Jing Li Juhu Zhang Haiyan School of Information Beijing Forestry University

This article investigates the significant performances of orthogonal frequency division multiplexing （OFDM）-based dual-hop system in the presence of phase noise （PN）. A scenario with Rayleigh fading statistics on both hops is assumed. Amplification factor for this amplify-and-forward （AF） relay networks system is divided into two conditions, average power scaling （APS） and instantaneous power scaling （IPS）. Before deriving signal-to-noise ratios （SNR） under APS and IPS, the Gaussianity of intercarrier interference （ICI） is proved firstly. The accurate closed-form expressions of end-to-end SNR cumulative distribution functions （CDF） and probability density functions （PDF） for both cases are obtained later. With the help of moment generating functions （MGF）, we have closed-form asymptotic expressions of bit error rate （BER）, which show that the BER of system in the presence of PN cannot exceed a fixed level even when SNR in high regime. Finally, simulations verify accuracy of the results. Conclusion analysis will provide a useful help in future application of the system.

关键词： OFDM-AF system phase noise average power scaling instantaneous power scaling