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Ming Li,1 Bahram Jalali,2 Keisuke Goda,3 Kevin K. Tsia4
1Institute of Semiconductors (China) 2Univ. of California, Los Angeles (United States) 3The Univ. of Tokyo (Japan) 4The Univ. of Hong Kong (Hong Kong, China)
This PDF file contains the front matter associated with SPIE Proceedings Volume 10026, including the Title Page, Copyright information, Table of Contents, and Conference Committee listing.
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This paper explores the use of honeycomb lattice waveguide meshes for universal linear operations and photonic
integrated circuit synthesis by programming a common hardware. We discuss the main photonic processor architecture,
the non-ideal effects to be considered and its application to different signal processing functionalities.
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Next generation fiber-wireless communication paradigms will require new technologies to address the current limitations
to massive capacity, connectivity and flexibility. Multicore optical fibers, which were conceived for high-capacity digital
communications, can bring numerous advantages to fiber-wireless radio access architectures. Besides radio over fiber
parallel distribution and multiple antenna connectivity, multicore fibers can implement, at the same time, a variety of
broadband processing functionalities for microwave and millimeter-wave signals. This approach leads to the novel
concept of “fiber-distributed signal processing”. In particular, we capitalize on the spatial parallelism inherent to
multicore fibers to implement a broadband tunable true time delay line, which is the basis of multiple processing
applications such as signal filtering, arbitrary waveform generation and squint-free radio beamsteering. We present the
design of trench-assisted heterogeneous multicore fibers composed of cores featuring individual spectral group delays
and chromatic dispersion profiles. Besides fulfilling the requirements for true time delay line operation, the MCFs are
optimized in terms of higher-order dispersion, crosstalk and bend sensitivity. Microwave photonics signal processing
will benefit from the performance stability, 2D operation versatility and compactness brought by the reported fiberintegrated
solution.
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Most of the efforts devoted to the area of optical communications were on the improvement of the optical spectral
efficiency. Varies innovative optical devices are thus developed to finely manipulate the optical spectrum. Knowing the
spectral responses of these devices, including the magnitude, phase and polarization responses, is of great importance for
their fabrication and application. To achieve high-resolution characterization, optical vector analyzers (OVAs) based on
optical single-sideband (OSSB) modulation have been proposed and developed. Benefiting from the mature and highresolution
microwave technologies, the OSSB-based OVA can potentially achieve a resolution of sub-Hz. However, the
accuracy is restricted by the measurement errors induced by the unwanted first-order sideband and the high-order
sidebands in the OSSB signal, since electrical-to-optical conversion and optical-to-electrical conversion are essentially
required to achieve high-resolution frequency sweeping and extract the magnitude and phase information in the electrical
domain. Recently, great efforts have been devoted to improve the accuracy of the OSSB-based OVA. In this paper, the
influence of the unwanted-sideband induced measurement errors and techniques for implementing high-accurate OSSB-based
OVAs are discussed.
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Arbitrary waveform generation attracts a lot of interests in recent years because of its widely applications in many different fields. We have proposed and experimentally demonstrate two on-chip pulse shaper schemes for microwave and optical arbitrary waveform generation. These schemes are all fabricated on
the silicon-on-insulator (SOI) chips for its compactness and capability to integrate with electronics. The
two schemes based on finite impulse response (FIR). By thermally controlling the amplitude and phase
of each path, we can obtain different applications of arbitrary waveform generation. The pulse shaper of optical arbitrary waveform generation can be a programmable filter with central wavelength tunable,
bandwidth tunable and passband shape variable functions, and a high-order differentiator which may
obtain the first-order, second-order and third-order differentiations likewise. It can also implement several typical optical waveforms, such as the square waveform, triangular waveform, sawtooth waveform and Gaussian waveform. The pulse shaper for microwave arbitrary waveform generation can
obtain several microwave waveforms with the central frequency at 125GHz. Comparing with the proposed schemes by frequency shaping and frequency-to-time mapping, our schemes do not require any spectral dispersers or large dispersion mediums. And all units in our schemes are broad-band devices, so there is no bandwidth limitation in our schemes.
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We propose and demonstrate optical true time delay using tapered SOI contradirectional couplers with single sidewallmodulated
Bragg gratings. The contradirectional couplers consist of two tapered rib waveguides with different width,
and the Bragg gratings are modulated in the inner sidewall of the wider one. The optical signal is launched from the wide
waveguide and coupled to the narrow waveguide through the Bragg gratings structure. Along the direction of light
propagation, the waveguide width varies linearly, so the reflection wavelength is different at different positions.
Therefore, linear delay line can be realized within the grating passband using the present structure. In the simulation,
grating period is 310nm and grating number is 2400, corresponding to the grating length of 744μm. Using 2.5D FDTD
simulation, the current structure can realize optical group delay of 20ps within bandwidth of 18nm. The proposed device
is fabricated on a 220nm SOI chip with Electron Beam Lithography (EBL) and Inductively Coupled Plasma (ICP)
etching. In the experiment, continuous light is modulated by 10GHz radio-frequency signal and travel through the chip,
which is finally detected by the oscilloscope. By adjusting the wavelength of input light, group delay of different
wavelength are recorded by the oscilloscope. The experimental results show that group delay of 28ps is realized within
the bandwidth of 20nm. In the end, the drift of the reflection spectrum and delay lines under different temperature are
analyzed. The reflection spectrum drifts 0.1nm/°C and causes redshift of the corresponding delay line.
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In this paper, a systematic review is made on our research related to photonics-assisted compressive sampling (CS)
systems including principle, structure and applications. We demonstrate their utility in wideband spectrum sensing and
high throughput flow cytometry. Photonics-assisted CS systems not only can significantly reduce the data acquisition
rate but also can achieve a large operational bandwidth (several GHz or even a few tens of GHz), which is one to two
orders of magnitude larger than that of traditional electric CS systems. Single-channel and multi-channel photonicsassisted
CS systems are presented in this paper and demonstrated to enable accurate reconstruction of frequency-sparse
signals from only a few percent of the measurements required for Nyquist sampling. On the other hand, we also
implement time-stretch-based single-pixel imaging systems with high frame rates, three orders of magnitude faster than
conventional single-pixel cameras. To show their utility in biomedical applications, a real-time high-throughput imaging
flow cytometer is demonstrated. In general, photonics-assisted CS systems show great potential in both wideband
spectrum sensing and biomedical imaging applications.
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A new microwave photonic approach to microwave frequency measurement with a high resolution and a large
bandwidth is proposed. In this method, three photonic sampling analog-to-digital converters (ADCs) with co-prime
sampling rates are employed. Three Fourier frequencies acquiring through down-converted analog-to-digital conversion
of the unknown microwave signal are utilized to recovery the frequency of the unknown signal. The simulation results
show that a microwave frequency measurement system which is feasible for multi-frequency microwave signal achieves
a large measurement range of 0-50GHz and an accuracy of±1MHz. In addition, the spur-free dynamic range of
101.1dB-Hz2/3@50GHz is also numerically demonstrated.
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Optical metrology techniques based on dual optical frequency combs have emerged as a hotly studied area targeting a
wide range of applications from optical spectroscopy to microwave and terahertz frequency measurement. Generating
two sets of high-quality comb lines with slightly different comb-tooth spacings with high mutual coherence and stability
is the key to most of the dual-comb schemes. The complexity and costs of such laser sources and the associated control
systems to lock the two frequency combs hinder the wider adoption of such techniques. Here we demonstrate a very
simple and rather different approach to tackle such a challenge. By employing novel laser cavity designs in a mode-locked
fiber laser, a simple fiber laser setup could emit dual-comb pulse output with high stability and good coherence
between the pulse trains. Based on such lasers, comb-tooth-resolved dual-comb optical spectroscopy is demonstrated.
Picometer spectral resolving capability could be realized with a fiber-optic setup and a low-cost data acquisition system
and standard algorithms. Besides, the frequency of microwave signals over a large range can be determined based on a
simple setup. Our results show the capability of such single-fiber-laser-based dual-comb scheme to reduce the
complexity and cost of dual-comb systems with excellent quality for different dual-comb applications.
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Chaotic semiconductor laser is a good candidate for secure communication and high-speed true random bit generator, for
its characteristics of broad bandwidth and prominent unpredictability. Based on the synchronization property and true
random bit generation characteristic of chaotic semiconductor lasers, physical secure key distribution is available. In this
work, we majorly show three key distribution schemes stemming from synchronized chaotic semiconductor lasers or
chaos-based key exchange protocol. The numerical results demonstrate that the security of the chaos-synchronization-based
key distribution scheme can be physically enhanced by adopting dynamic synchronization scheme or encrypted
key generation, and that of key distribution with chaos-based key exchange protocol is dependent on the security of the
exchange protocol and finally determined by the difficulty of regeneration the chaos system accurately.
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The world is faced with environmental problems and the energy crisis due to the combustion and depletion of fossil
fuels. The development of reliable, sustainable, and economical sources of alternative fuels is an important, but
challenging goal for the world. As an alternative to liquid fossil fuels, algal biofuel is expected to play a key role in
alleviating global warming since algae absorb atmospheric CO2 via photosynthesis. Among various algae for fuel
production, Euglena gracilis is an attractive microalgal species as it is known to produce wax ester (good for biodiesel
and aviation fuel) within lipid droplets. To date, while there exist many techniques for inducing microalgal cells to
produce and accumulate lipid with high efficiency, few analytical methods are available for characterizing a population
of such lipid-accumulated microalgae including E. gracilis with high throughout, high accuracy, and single-cell
resolution simultaneously. Here we demonstrate a high-throughput optofluidic Euglena gracilis profiler which consists
of an optical time-stretch microscope and a fluorescence analyzer on top of an inertial-focusing microfluidic device that
can detect fluorescence from lipid droplets in their cell body and provide images of E. gracilis cells simultaneously at a
high throughput of 10,000 cells/s. With the multi-dimensional information acquired by the system, we classify nitrogen-sufficient
(ordinary) and nitrogen-deficient (lipid-accumulated) E. gracilis cells with a low false positive rate of 1.0%.
This method provides a promise for evaluating the efficiency of lipid-inducing techniques for biofuel production, which
is also applicable for identifying biomedical samples such as blood cells and cancer cells.
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Optical computed tomography is an important technique in the visualization and diagnosis of various flow fields. A
small-scale diffusion flame was visualized using deflection tomography. A projection sampling system was proposed for
deflection tomography to obtain deflectograms with a pair of gratings. Wave-front retrieval was employed for processing
the deflectograms to obtain the deflection angles of the rays. This two-dimensional data extraction method expanded the
application of deflection tomography and was suitable for the projection extraction of small-scale combustion. Deflection
angle revision reconstruction algorithm was used to reconstruct the temperature distributions in 10 cross sections for
each deflectogram in different instants. The flow structure was reconstructed using a visualization toolkit equipped with
the marching cube and ray casting algorithms. The performed experiments demonstrated the three-dimensional dynamic
visualization of temperature distributions and the flame structures of small-scale diffusion combustion.
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In spectroscopy data analysis, such as Raman spectra, X-ray diffraction, fluorescence and etc., baseline drift is a ubiquitous issue. In high speed testing which generating huge data, automatic baseline correction method is very important for efficient data processing. We will survey the algorithms from classical Shirley background to state-of-the-art methods to present a summation for this specific field. Both advantages and defects of each algorithm are scrutinized. To compare the algorithms with each other, experiments are also carried out under SVM gap gain criteria to show the performance quantitatively. Finally, a rank table of these methods is built and the suggestions for practical choice of adequate algorithms is provided in this paper.
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With the emergence of UAV (unmanned aerial vehicle) platform for aerial imaging spectrometer, research of aerial
imaging spectrometer DAS(data acquisition system) faces new challenges. Due to the limitation of platform and other
factors, the aerial imaging spectrometer DAS requires small-light, low-cost and universal. Traditional aerial imaging
spectrometer DAS system is expensive, bulky, non-universal and unsupported plug-and-play based on PCIe. So that has
been unable to meet promotion and application of the aerial imaging spectrometer.
In order to solve these problems, the new data acquisition scheme bases on USB3.0 interface.USB3.0 can provide
guarantee of small-light, low-cost and universal relying on the forward-looking technology advantage. USB3.0
transmission theory is up to 5Gbps.And the GPIF programming interface achieves 3.2Gbps of the effective theoretical
data bandwidth.USB3.0 can fully meet the needs of the aerial imaging spectrometer data transmission rate. The scheme
uses the slave FIFO asynchronous data transmission mode between FPGA and USB3014 interface chip. Firstly system
collects spectral data from TLK2711 of high-speed serial interface chip. Then FPGA receives data in DDR2 cache after
ping-pong data processing. Finally USB3014 interface chip transmits data via automatic-dma approach and uploads to
PC by USB3.0 cable.
During the manufacture of aerial imaging spectrometer, the DAS can achieve image acquisition, transmission, storage
and display. All functions can provide the necessary test detection for aerial imaging spectrometer. The test shows that
system performs stable and no data lose. Average transmission speed and storage speed of writing SSD can stabilize at
1.28Gbps. Consequently ,this data acquisition system can meet application requirements for aerial imaging spectrometer.
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In this work, a fully strained GeSn photodetector with Sn atom percent of 8% is fabricated on Ge buffer on Si(001)
substrate. The wavelength λ of light signals with obvious optical response for Ge0.92Sn0.08 photodetector is extended to 2
μm. The impacts of compressive strain introduced during the epitaxial growth of GeSn on Ge/Si are studied by
simulation. Besides, the tensile strain engineering of GeSn photonic devices is also investigated. Lattice-matched
GeSn/SiGeSn double heterostructure light emitting diodes (LEDs) with Si3N4 tensile liner stressor are designed to
promote the further mid-infrared applications of GeSn photonic devices. With the releasing of the residual stress in Si3N4
liner, a large biaxial tensile strain is induced in GeSn active layer. Under biaxial tensile strain, the spontaneous emission
rate rsp and internal quantum efficiency ηIQE for GeSn/SiGeSn LED are significantly improved.
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In the paper, the Long period fiber gratings (LPFG) were fabricated in a single-mode fiber using a high frequency CO2
laser system with the point-to-point technique. The experimental setup consists of a CO2 laser controlling system, a
focusing system located at a motorized linear stage, a fiber alignment stage, and an optical spectrum analyzer to monitor
the transmission spectrum of the LPFG. The period of the LPFG is precisely inscribed by periodically turning on/off the
laser shutter while the motorized linear stage is driven to move at a constant speed. The efficiency of fiber writing
process is improved.
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We studied the in-line DFB tunable laser based on REC technique. We mapped the contour lines of the P-I contour diagram of this in-line tunable laser into the wavelength-current contour map. And the maximum output power is obtained.
Also the tuning currents are obtained. Firstly, we simulated the P-I contour as well as wavelength-current contour. Secondly, we experimentally demonstrated the mapped
contour.
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We numerically calculate and experimentally investigate the characterization of phase-shifted Brillouin dynamic gratings
(PS-BDGs) in a polarization maintaining fiber (PMF). A phase-shifted point is induced into the middle of a conventional
BDG through phase-modulating one of the two pump pulse, generating a PS-BDG thanks to the stimulated Brillouin
scattering (SBS). When the frequency difference between a high frequency pump1 pulse with 1ns and π-1ns and a low
frequency pump2 pulse with 100ps is equal to the Brillouin frequency shift of the PMF, a transient PS-BDG with a 3dBbandwidth
of 354MHz of the notch spectrum is simulated based on the coupled-wave equations of BDG. By increasing
the repetition rate up to 250MHz, an enhanced PS-BDG with a deep notch depth is obtained since the residual acoustic
wave of the former SBS process is enhanced by the optical waves of the latter SBS process. Then a proof-of-concept
experiment is built to verify the transient PS-BDG and the results show that the notch feature is consistent with the
simulation results and the notch frequency of the PS-BDG can be changed by tuning the phase shift Δϕ . The proposed
PS-BDGs have important potential applications in optical fiber sensing, microwave photonics, all-optical signal
processing and RoF (radio-over-fiber) networks.
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A tunable optoelectronic oscillator (OEO) for detecting low-power radiofrequency (RF) signals is proposed and
experimentally demonstrated. The tunable OEO is mainly composed of a tunable laser source, a phase modulator, a
phase-shifted fiber Bragg grating (PS-FBG) and a photodetector. The PS-FBG is used as a notch filter to remove one
sideband of the phase-modulated signal to realize the phase modulation to intensity modulation conversion, which
determines the main oscillation mode of the OEO. The frequency of the RF signal under detection can be estimated by
the frequency difference between the optical carrier from the TLS and the notch of the PS-FBG. The RF signal as low as
-75 dBm is detected with a dynamic range of 80 dB. The RF signals from 1.5 to 4.5 GHz are selectively amplified with a
gain of about 7dB.
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Chemical Oxygen Demand (COD) and Nitrate concentration data are of vital importance in coastal water quality
monitoring. The traditional method for monitoring these two parameters is a chemical method that consumes chemical
reagent. The drawbacks of these chemical methods are the waste they generate, and the difficulty in implementing in-situ
long term monitoring. A new instrument based on an optical method to measure Chemical Oxygen Demand and Nitrate
concentration without reagent is described in this paper. According to the different water quality, optical path length of
flow cell is variable in this system. A 10 mm path length is selected in this paper. And a Y type of structure of quartz
optical fibers is used for real-time compensation. Concentration calculation principle is based on the analysis of
absorption spectrum and partial least square method. Comparison between model calculation and experimental data is
also discussed in detail with several test samples. The implementation of standard test and measurements for the
collected water samples is presented in this paper.
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Flame tomography of chemiluminescence is a necessary combustion diagnostic technique that provides instantaneous
3D information on flame structure and excited species concentrations. However, in most research, the simplification of
calculation model of weight coefficient based on lens imaging theory always causes information missing, which
influences the result of further reconstructions. In this work, an improved calculation model is presented to determine
the weight coefficient by the intersection areas of the blurry circle with the square pixels, which is more appropriate to
the practical imaging process. The numerical simulation quantitatively evaluates the performance of the improved
calculation method. Furthermore, a flame chemiluminescence tomography system consisting of 12 cameras was
established to reconstruct 3D structure of instantaneous non-axisymmetric propane flame. Both numerical simulating
estimations and experiments illustrate the feasibility of the improved calculation model in combustion diagnostic.
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To improve the denoising effect of the glucose photoacoustic signals, a modified wavelet thresholding combined
shift-invariance algorithm was used in this paper. In addition, the shift-invariance method was added into the improved
algorithm. To verify the feasibility of modified wavelet shift-invariance threshold denoising algorithm, the simulation
experiments were performed. Results show that the denoising effect of modified wavelet shift-invariance thresholding
algorithm is better than that of others because its signal-to-noise ratio is largest and the root-mean-square error is lest.
Finally, the modified wavelet shift-invariance threshold denoising was used to remove the noises of the photoacoustic
signals of glucose aqueous solutions.
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A new passive millimeter-wave (PMMW) image acquisition and reconstruction method is proposed based on
compressed sensing (CS) and spatial sparse scanned imaging. In this method, the images are sparse sampled through a
variety of spatial sparse scanned trajectories, and are reconstructed by using conjugate gradient-total variation recovery
algorithm. The principles and applications of CS theories are described, and the influence of the randomness of the
measurement matrix on the quality of reconstruction images is studied. Based on the above work, the qualities of the
reconstructed images which were obtained by the sparse sampling method were analyzed and compared. The research
results show that the proposed method can effectively reduce the image scanned acquisition time and can obtain
relatively satisfied reconstructed imaging quality.
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According to the thermal control coatings and the requirement of lunar sample sealing device parameters measuring The
Non-contact measuring equipment is designed and calibrated. Some relevant experimentation is carried out and
experiment result shows that the error of optical measuring system is consist with the contact measuring system in the
Non-contact measuring equipment and the Non-contact measuring equipment can be used to measure characteristic
parameters of lunar sample sealing device.
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The requirement of high range resolution results in impractical collection of every returned laser pulse due to the limited response speed of imaging detectors. This paper proposes a phase coded sequence acquisition method for signal preprocessing. The system employs an m-sequence with N bits for demonstration with the detector controlled to accumulate N+1 bits of the echo signals to deduce one single returned laser pulse. An indoor experiment achieved 2 μs resolution with the sampling period of 28 μs by employing a 15-bit m-sequence. This method shows the potential to improve the detection capabilities of narrow laser pulses with the detectors at a low frame rate, especially for the imaging lidar systems. Meanwhile, the lidar system is able to improve the range resolution with available detectors of restricted performance.
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In a nuclear-magnetic-resonance gyroscope (NMRG), the polarization of nuclear spins and the detection of motional
information are usually achieved by utilizing the atomic spins of alkali atoms. The parameters of the atomic spins are
mainly evaluated by the relaxation time. Relaxation time is very important and can influence signal-to-noise ratio,
dynamic range, start time, and other gyroscope parameters. Therefore, its accurate measurement is critical in the study of
NMRG performance. In this study, we evaluate a variety of methods to measure the transverse and longitudinal
relaxation times. First we examine the free-induction-decay method, which is the industry standard for measuring spin
relaxation time. Second we investigate the improved free-induction-decay, fitting-ratio, and magnetic-resonance-broadening-
fitting methods for measuring the transverse relaxation time, and the flipped polarization method for
measuring the longitudinal relaxation time. By changing the experimental conditions, we obtain the longitudinal
relaxation time using the flipped polarization method under a variety of conditions. Finally, by comparing these
measurement methods, we propose the best measurement methods under different conditions.
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The real-time distance measurement system with dual femtosecond comb lasers combines time-of–flight and interferometric measurement. It has advantages of wide-range, high-accuracy and fast speed at the rate about 10000 pts/s. Such a distance measurement system needs dedicated higher performance of the data acquisition and processing hardware platform to support. This paper introduces the dedicated platform of the developed absolute distance measurement system. This platform is divided into three parts according to their respective functions. First part is the data acquisition module, which function is mainly to realize the A/D conversion. In this part we designed a sampling clock adjustment module to assist the A/D conversion module to sample accurately. The sampling clock adjustment module accept a 250MHz maximum reference clock input, which from the same femtosecond laser source as the optical measurement system, then generate an output clock for the A/D converter that can be delayed up to 20ns with a resolution of 714ps. This data acquisition module can convert the analog laser pulse signal to digital signal with a 14 bits resolution and a 250 MSPS maximum sample rate. Second is the data processing and storage module consists of FPGA and DDR3 modules. The FPGA module calculates the test distance by the 16 bits digital sampling signal from the front data acquisition module. The DDR3 module implements sampling data caching. Finally part is the data transmission and peripheral interfaces module based on three DB9 and USB2.0. We can easily debug the platform in the PC and implement communication with upper machine. We tested our system used dedicate test bench in real-time. The scope of the measurement system range is 0 to 3 meters and the measurement deviation is less than 10um.
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Correlating Shack-Hartmann wavefront sensor is widely used in solar adaptive optics in which the relative shift between
different subapertures by correlation algorithm is computed, and then the control voltage by wavefront
reconstruction can be estimated to use for correcting the wavefront distortion induced by atmospheric turbulence. In this
paper, several different correlation algorithms including Cross-Correlation Coefficient, Absolute Difference Function,
Absolute Difference Function-Squared and Square Difference Function are used to estimate relative shift in correlating
Shack-Hartmann wave-front sensor with the different observed solar structure such as sunspot, solar pore and solar
granulation. The measurement noise RMS error is computed to compare the performance of the correlation algorithms.
The results show the correlation algorithm precision is directly related to the solar structure. The measurement noise is
relatively small with the relatively high contrast target, and vice versa. At the same time, the size of reference image also
could influence the measurement noise, the larger size of the reference image, the smaller the measurement noise is.
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In the paper, an accurate and sensitive cavity attenuated phase shift spectroscopy (CAPS) sensor was used to monitor the
atmospheric visibility. The CAPS system mainly includes a LED light source, a band-pass filter, an optical resonant
cavity (composed of two high mirror, reflectivity is greater than 99.99%), a photoelectric detector and a lock-in amplifier.
The 2L/min flow rate, the optical sensor rise and fall response time is about 15 s, so as to realize the fast measurement of
visibility. An Allan variance analysis was carried out evaluating the optical system stability (and hence the maximum
averaging time for the minimum detection limit) of the CAPS system. The minima (~0.1 Mm-1) in the Allan plots show
the optimum average time (~100s) for optimum detection performance of the CAPS system. During this period, the
extinction coefficient was correlated with PM2.5 mass (0.88), the extinction coefficient was correlated with PM10 mass
(0.85). The atmospheric visibility was correlated with PM2.5 mass (0.74). The atmospheric visibility was correlated with
PM10 mass (0.66).
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As an extension of High Efficiency Video Coding ( HEVC), 3D-HEVC has been widely researched under the impetus of
the new generation coding standard in recent years. Compared with H.264/AVC, its compression efficiency is doubled
while keeping the same video quality. However, its higher encoding complexity and longer encoding time are not
negligible. To reduce the computational complexity and guarantee the subjective quality of virtual views, this paper
presents a novel video coding method for 3D-HEVC based on the saliency informat ion which is an important part of
Human Visual System (HVS). First of all, the relationship between the current coding unit and its adjacent units is used
to adjust the maximum depth of each largest coding unit (LCU) and determine the SKIP mode reasonably. Then,
according to the saliency informat ion of each frame image, the texture and its corresponding depth map will be divided
into three regions, that is, salient area, middle area and non-salient area. Afterwards, d ifferent quantization parameters
will be assigned to different regions to conduct low complexity coding. Finally, the compressed video will generate new
view point videos through the renderer tool. As shown in our experiments, the proposed method saves more bit rate than
other approaches and achieves up to highest 38% encoding time reduction without subjective quality loss in compression
or rendering.
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In order to measure the coordinate of moving target, the laser tracking system for moving target was proposed, in which the receiver of four-quadrant APD was adopted as the detector and the DC motor was used to drive the reflector to move in two dimensions. The principle of the measurement system was analyzed first. Then the main part of the system was introduced. The tracking experiment showed that, this system could realized the function of automatic tracking and measuring the coordinate of moving target according to the pulsed laser ranging and angle sensors.
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