- 标题
- 摘要
- 关键词
- 实验方案
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LUT-Free Carrier Recovery for Intradyne Optical DPSK Receivers in udWDM-PON
摘要： We present an LUT-free carrier recovery architecture for intradyne optical DPSK receivers that reduces the required DSP hardware resources, power consumption as well as total process clocks, aimed at cost-effective transceivers for access networks applications. The proposed architecture simplifies frequency compensation algorithm to avoid using mth-power operation and LUTs. We prototyped the proposed carrier recovery on a commercial FPGA for real-time evaluation with data at 1.25Gb/s. The optical transmission system is implemented by direct-phase modulation of commercial DFB lasers, 25 km of single-mode fiber, and a coherent receiver with low-cost optical front-end based on 3x3 coupler and three photodiodes providing phase-diversity operation. Results show high performance in real-time, achieving -54 dBm sensitivity at BER = 10-3 as well as feed-forward frequency error correction, high robustness against the fast frequency laser drifts, and high tolerance to optical phase noise in a 6.25GHz spaced ultra-dense WDM grid.
关键词： phase shift keying,FPGA,digital signal processing,Carrier recovery,frequency estimation
更新于2025-09-23 15:22:29
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Adaptive Nonlinear Equalization of a Tunable Bandpass Filter
摘要： The mitigation of third-order intermodulation distortion produced by a nonlinear tunable bandpass filter (BPF) in a digital receiver channel is demonstrated. An iterative solution is proposed, in the use of the least-mean-square algorithm, as an effective way to allow the correction coefficients to adapt to the changes in the system characteristics when the center frequency is changed. Results are shown using a two-pole, varactor-loaded BPF, and an Analog Devices AD9371 transceiver.
关键词： Adaptive signal processing,nonlinear distortion and intermodulation distortion (IMD),nonlinear filters,least mean square
更新于2025-09-23 15:22:29
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S-Type Negative Differential Resistance in Semiconducting Transition-Metal Dichalcogenides
摘要： Current-controlled (also known as “S-type”) negative differential resistance (NDR) is of crucial importance to many emerging applications including neuromorphic computing and high-density memristors integration. However, the experimental realization of S-type NDR based on conventional mechanisms poses demanding requirements on materials, which greatly limits their potential applications. Here, it is experimentally identified that semiconducting transition-metal dichalcogenides (TMDs) can host a bipolar S-type NDR devices. Theoretical simulations indicate that the origin of the NDR in these devices arises from a thermal feedback mechanism. Furthermore, the potential applications of TMD-based S-type NDR device in signal processing and neuromorphic electronics are demonstrated.
关键词： transition-metal dichalcogenides,signal processing,negative differential resistance,self-oscillating circuits,neuron spikes
更新于2025-09-23 15:22:29
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Microwave Photonic Devices Based on Liquid Crystal on Silicon Technology
摘要： This paper reviews the recent developments in microwave photonic devices based on liquid crystal on silicon (LCOS) technology. The operation principle, functions and important specifications of an LCOS based optical processor are described. Three microwave photonic devices, which are microwave photonic notch filters, phase shifters and couplers, reported in the past five years are focused on in this paper. In addition, a new multi-function signal processing structure based on amplitude and phase control functions in conjunction with a power splitting function in a commercial LCOS based optical processor is presented. It has the ability to realize multiple time-shifting operations and multiple frequency-independent phase shifting operations at the same time and control multiple RF signal amplitudes, in a single unit. The results for the new multi-function microwave photonic signal processor demonstrate multiple tunable true time delay and phase shifting operations with less than 3 dB amplitude variation over a very wide frequency range of 10 to 40 GHz.
关键词： phase shifters,optical signal processing,filters,true time delays,microwave photonics
更新于2025-09-23 15:22:29
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Online Mutual Foreground Segmentation for Multispectral Stereo Videos
摘要： The segmentation of video sequences into foreground and background regions is a low-level process commonly used in video content analysis and smart surveillance applications. Using a multispectral camera setup can improve this process by providing more diverse data to help identify objects despite adverse imaging conditions. The registration of several data sources is however not trivial if the appearance of objects produced by each sensor differs substantially. This problem is further complicated when parallax effects cannot be ignored when using close-range stereo pairs. In this work, we present a new method to simultaneously tackle multispectral segmentation and stereo registration. Using an iterative procedure, we estimate the labeling result for one problem using the provisional result of the other. Our approach is based on the alternating minimization of two energy functions that are linked through the use of dynamic priors. We rely on the integration of shape and appearance cues to find proper multispectral correspondences, and to properly segment objects in low contrast regions. We also formulate our model as a frame processing pipeline using higher order terms to improve the temporal coherence of our results. Our method is evaluated under different configurations on multiple multispectral datasets, and our implementation is available online.
关键词： Multispectral imagery,Energy minimization,Cosegmentation,Video signal processing,Video object segmentation
更新于2025-09-23 15:22:29
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[IEEE 2018 15th European Radar Conference (EuRAD) - Madrid, Spain (2018.9.26-2018.9.28)] 2018 15th European Radar Conference (EuRAD) - A New Antenna Array and Signal Processing Concept for an Automotive 4D Radar
摘要： On the way to Highly Automated Driving (HAD), new conditions for sensors used in vehicles arise. To achieve a highly accurate environmental perception the resolution of radar sensors has to be increased. Only with ?ne grained sensor information, is possible to maneuver safely and highly automated at all road conditions in urban and rural surroundings. A prototypical implementation of such a sensor, which ful?lls all these requirements, is presented in the following as automotive 4D radar. The relevant parts of the baseband signal processing are explained in combination with the used modulation waveform. A new antenna array arrangement is introduced which provides the ability to measure angles in both azimuth and elevation. To estimate the two angles of arrival a method which performs this in combination is exempli?ed. First measurements with a cyclist are recorded and show a radial speed enhanced 3D radar image. The ?rst results are extremely promising. For validation of the measured data, also a simulation of the same scenario with identical system parameters is performed and shown.
关键词： automotive radar,2d angular estimation,angular estimation,signal processing
更新于2025-09-23 15:21:21
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[IEEE 2018 15th European Radar Conference (EuRAD) - Madrid, Spain (2018.9.26-2018.9.28)] 2018 15th European Radar Conference (EuRAD) - Distributed Signal Processing of High-Resolution FMCW MIMO Radar for Automotive Applications
摘要： For driving automated applications, high resolution radar systems are necessary to extract more information about different types of objects in the environment. However, a single automotive microcontroller might not be sufficient to processing high number of transmit and receive antenna channels. Hence, in this paper, a system concept for distributed signal processing of high resolution FMCW MIMO radar has been proposed to highlight the feasibility using automotive microcontrollers. The execution time and computaional/memory requirements show the feasibility of such systems for automotive safety applications.
关键词： signal processing,FMCW,high resolution radar,MIMO,automotive
更新于2025-09-23 15:21:21
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Design and Analysis of GeSn-based Resonant-Cavity-Enhanced Photodetectors for Optical Communication Applications
摘要： Touch-based interactivity has become an important function in displays. This paper reports on the signal processing of touch signals in which touch interactivity is processed as an image, and correlated double sampling (CDS) algorithm is applied for both common-mode noise reduction and global multivalued offset cancellation. Based on experimental results, we achieved a boost in SNR of 7.6 dB. The processed signal reduces detection errors and power consumption of the system.
关键词： Capacitance touchscreen,common-mode noise,global multivalued offset,correlated double sampling (CDS),image signal processing
更新于2025-09-23 15:21:01
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[IEEE 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Chicago, IL, USA (2019.6.16-2019.6.21)] 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Significant improvement on electrical properties of BaSi <sub/>2</sub> due to atomic H passivation by radio-frequency plasma
摘要： We demonstrate for the ?rst time an intensity-modulated direct-detection link using four states of polarization. The four data-independent tributaries are each assigned distinct states of polarization to enable the receiver to separate the signals. Polarization rotation due to propagation over optical ?ber is tracked and compensated with simple digital signal processing in Stokes space. Transmission below the forward error correction limit is shown for maximum net bitrates of 100 Gb/s (4 × 27 GBd) and 120 Gb/s (4 × 32 GBd) over 2-km standard single-mode ?ber at a center wavelength of 1550 nm.
关键词： direct detection (DD),intensity modulation (IM),digital signal processing,Stokes space,100G,polarization
更新于2025-09-23 15:21:01
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[IEEE 2019 Device Research Conference (DRC) - Ann Arbor, MI, USA (2019.6.23-2019.6.26)] 2019 Device Research Conference (DRC) - Field Effect and Raman Characterization of Self-Assembled Mos <sub/>2</sub> Nanoscrolls
摘要： In bistatic multiple input multiple output (MIMO) radar, more number of detectable incident signals and a higher angle estimation performance can be obtained by using conjugate estimation of signal parameters via rotational invariance techniques (ESPRITs) with the characteristic of noncircularity. The result is achieved under the assumption that all the received signals are noncircular. When the incident signals are the coexistence of noncircular and circular signals, the conjugate ESPRIT will not valuable. Therefore, this paper proposes a method of the joint of direction of departure (DOD) and direction of arrival (DOA) estimation, which is appropriate for the coexistence of noncircular and circular signals in bistatic MIMO radar. First, the received data model of the bistatic MIMO radar is given. Second, we modify the received signal model by the use of noncircularity characteristic. Third, we derive out the equation of spatially rotational invariant containing the DOD and DOA information. Last, we solve the equation to obtain the DOD and DOA by means of total least squares technology. The proposed algorithm has the three advantages. One is that it has better angle estimation accuracy than that of method which does not use the noncircularity characteristic. Another one is that it has more number of detectable incident signals. The last one is that the more number of noncircular signals, the higher angle estimation accuracy will be. Results from numerical experiments are used to show the effectiveness of our proposed algorithm.
关键词： ESPRIT,noncircular,DOA estimation,MIMO radar,Array signal processing
更新于2025-09-23 15:21:01