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1

Four channel optical demultiplexer based on L2 photonic crystal microcavity

Ammari Merzoug, Benmerkhi Ahlem, Bouchemat Mohamed

Optica Applicata

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2022

|

Vol. 52, nr 4

613--625

EN

The wavelength demultiplexing is a particularly important function in integrated optics and can be realized using photonic crystals. The aim is to extract accurately the wavelengths in a data flux. In this work, we investigate a new topologies of wavelength demultiplexing based on two-dimensional photonic crystals constituted of dielectric rods spread in a square network. The studied demultiplexer is based on optical filters with optimized parameters in order to extract four different wavelengths in the vicinity of frequencies corresponding to communication windows. It was found that the crosstalk between the structure channels of the demultiplexer are in the range of –19.19 and – 44.1 dB and the channel spacing is equal to 0.96 nm. The simulation results presented in this paper are performed and analyzed using the FDTD method.

2

Optical multiple-image encryption in discrete multiple-parameter fractional Fourier transform scheme using complex encoding, theta modulation and spectral fusion

Luan Guangyu, Zhong Zhi, Shan Mingguang

Optica Applicata

|

2021

|

Vol. 51, nr 1

121--134

EN

We present a novel encryption method for multiple images in a discrete multiple-parameter fractional Fourier transform scheme, using complex encoding, theta modulation and spectral fusion. All pairs of original images are encoded separately into a complex signal. The spectrum of each complex signal can then be scattered into various positions in the spectral plane and multiplexed into one spectral image with a combination of theta modulation and spectral fusion. After Fourier transforming back to the spatial domain, the multiplexed signal is encrypted in the discrete multiple-parameter fractional Fourier transform domain. Information about the original images can only be successfully decrypted given the possession of all correct keys. The parameters of chaotic pixel scrambling for the proposed method enlarge the key space. Moreover, the proposed method solves the crosstalk problem of multiple images and improves the multiplexing capacity. Numerical simulations demonstrate the effectiveness of the proposed method.

3

Monitoring w inteligentnych sieciach elektroenergetycznych (Smart Grid)

Maśnicki R., Lisowski M.

Zeszyty Naukowe Akademii Morskiej w Gdyni

|

2018

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nr 103

73---84

PL

Dzięki postępowi w różnych dziedzinach elektrotechniki tradycyjne elektroenergetyczne sieci przesyłowe i dystrybucyjne przekształcane są w inteligentne sieci elektroenergetyczne. Integralną częścią sieci o takiej konfiguracji jest medium komunikacyjne, stanowiące warstwę fizyczną sieci komunikacyjnej, umożliwiającej wymianę różnorodnych danych w ramach sieci. Liczne aplikacje zaprojektowane dla sieci inteligentnych, np. umożliwiające zdalne odczyty liczników energii, w większości wymagają niewielkiej szybkości transmisji danych, dla której wystarczające warunki stwarzają techniki komunikacji wąskopasmowej. W artykule omówiono podstawowe założenia inteligentnych sieci energetycznych oraz wskazano wybrane standardy komunikacji implementowane w tych sieciach. Nakreślono istotny problem związany z ich użytkowaniem: przesłuchy pomiędzy segmentami sieci. Przedstawiono koncepcję rozwiązania tego problemu i przywołano wstępne wyniki badań symulacyjnych.

EN

With advances in various fields of electrical engineering, traditional power transmission and distribution grids are transformed into intelligent power grids. An integral part of a network with this configuration is the communication medium, which is the physical layer of the communication network, allowing for the exchange of diverse data within the network. Numerous applications designed for intelligent networks, such as enabling remote reads of power meters, mostly require a low data rate, for which sufficient conditions create narrowband communications. The article discusses the basic assumptions of intelligent power grids and indicates selected communication standards implemented in these networks. A significant issue related to their use was identified: crosstalk among network segments. The concept of solving this problem was presented and preliminary results of simulation tests were recalled.

4

Integrated 25 GHz and 50 GHz spectral line width dense wavelength division demultiplexer on single photonic crystal chip

Balaji V. R., Murugan M., Robinson S., Nakkeeran R.

Opto-Electronics Review

|

2018

|

Vol. 26, No. 4

285--295

EN

We propose a new integrated demultiplexer model using the two-dimensional photonic crystal (2D PC) through the hexagonal resonant cavity (HRC) for the International Telecommunication Union (ITU) standard. The integrated model of demultiplexer for both 25 GHz and 50 GHz has been designed for the first time. The demultiplexer consists of bus input waveguide, drop waveguide, Hexagonal Resonant Cavity (HRC), 6 Air Hole Filter (6-AHF), 7 Air Hole Filter (7-AHF). The 7-AHF is used to filter 25GHz wavelength, and the 6-AHF filter is used to filter 50 GHz wavelength. The Q-factor on the designed demultiplexer is flexible based on the idea of increasing the number of air holes between drop waveguide and resonant cavity. The demultiplexer is designed to drop maximum 8 resonant wavelengths. One side of demultiplexer is able to drop 50 GHz ITU standard wavelengths, which are of 1556.3 nm, 1556.7 nm, 1557.1 nm and 1557.5 nm, and further the other facet is able to drop 25 GHz wavelengths, which are of 1551.4 nm, 1551.6 nm, 1551.8 nm, and 1552.0 nm. The proposed demultiplexer may be carried out within the integrated dual system. This system is able to lessen the architecture cost and the size is miniaturized substantially.

5

Research on the statistical characteristics of crosstalk in naval ships wiring harness based on Polynomial Chaos Expansion method

Chi Y., Li B., Yang X., Wang T., Yang K., Gao Y.

Polish Maritime Research

|

2017

|

S 2

205--214

EN

Crosstalk in wiring harness has been studied extensively for its importance in the naval ships electromagnetic compatibility field. An effective and high-efficiency method is proposed in this paper for analyzing Statistical Characteristics of crosstalk in wiring harness with random variation of position based on Polynomial Chaos Expansion (PCE). A typical 14-cable wiring harness was simulated as the object of research. Distance among interfering cable, affected cable and GND is synthesized and analyzed in both frequency domain and time domain. The model of naval ships wiring harness distribution parameter was established by utilizing Legendre orthogonal polynomials as basis functions along with prediction model of statistical characters. Detailed mean value, mean square error, probability density function and reasonable varying range of crosstalk in naval ships wiring harness are described in both time domain and frequency domain. Numerical experiment proves that the method proposed in this paper, not only has good consistency with the MC method can be applied in the naval ships EMC research field to provide theoretical support for guaranteeing safety, but also has better time-efficiency than the MC method. Therefore, the Polynomial Chaos Expansion method.

6

Improved low channel spacing high quality factor four-channel demultiplexer based on photonic crystal ring resonators

Talebzadeh R., Soroosh M., Mehdizadeh F.

Optica Applicata

|

2016

|

Vol. 46, nr 4

553--564

EN

In this paper, we propose a compact structure to realize the demultiplexing operation for dense wavelength division multiplexing communication systems using improved shell-type ring resonators in a photonic crystal structure. The cross-section of the structure is 790 μm2 and is desirable for integration based on popular planar technology. To improve power transmission coupling efficiency, we introduce the phase matching condition between ring resonators and waveguides; the results exhibit near 100% transmission efficiency. To obtain a high quality factor, we use interior lower refractive indices spheres inside the ring resonators as the mirrors; a quality factor as high as 15497 is achieved. The average pass bands of channels are near 0.1 nm, and the channel spacing is approximately 0.6 nm. The wavelengths of the demultiplexer are 1549, 1549.7, 1550.3 and 1550.9 nm. The crosstalk is between –14 and –29 dB, and the mean value of the crosstalk is –18.39 dB.

7

Model of multipath propagation of ultrasonic pulses generated in soft tissue by linear arrays

Celmer M., Opieliński K. J.

Hydroacoustics

|

2016

|

Vol. 19

37--48

EN

Arrays of ultrasonic transducers used in medical diagnosis for safe and non-invasive visualization of the inside of a human body usually consist of many elementary piezoceramic transducers. In such an electromechanical construction of the array, while activating individual transducers, creation of crosstalk can be observed in the form of propagation of electric voltage and mechanical vibration on neighboring elements, which leads to distortion of the generated acoustical field, and in consequence reduces the quality of reconstructed medical images. Complexity of the problem rises rapidly in the case of arrays forming ultrasonic beams. In this paper, authors developed a numerical amplitude-phase model of multipath propagation of ultrasonic pulses generated in a soft tissue-like medium by such arrays. The model allowed simulation of acoustic field distributions, and to examine the influence of beam focusing in transmission mode on these distributions, taking into account electrical and mechanical crosstalk.

8

Mutual Clutter Suppression Techniques for FM Sonars

Marszal J., Rudnicki M., Jedel A., Salamon R., Kochańska I.

Archives of Acoustics

|

2016

|

Vol. 41, No. 4

721--729

EN

The article presents methods that help in the elimination of mutual clutter as well as the consequences of two FM sounding signal sonars operating in the same body of water and frequency band. An in-depth analysis of mutual clutter was carried out. The effects of sounding signal differentiation were determined, as was the Doppler effect on mutual clutter suppression. One of the methods analysed is of particular interest in a situation in which collaborating sonars are operating in opposite frequency modulation directions. This method is effective for both linear and hyperbolic frequency modulations. A formula was derived, identifying exactly how much quantities of clutter may be lessened. The work included comprehensive computer simulations and measurements as well as tests in real-life conditions.

9

New Structure of Test Pattern Generator Stimulating Crosstalks in Bus-type Connections

Garbolino T.

International Journal of Electronics and Telecommunications

|

2015

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Vol. 61, No. 1

67-75

EN

The paper discloses the idea of a new structure for a Test Pattern Generator (TPG) for detection of crosstalk faults that may happen to bus-type interconnections between built in blocks within a System-on-Chip structure. The new idea is an improvement of the TPG design proposed by the author in one of the previous studies. The TPG circuit is meant to generate test sequences that guarantee detection of all crosstalk faults with the capacitive nature that may occur between individual lines within an interconnecting bus. The study comprises a synthesizable and parameterized model developed for the presented TPG in the VLSI Hardware Description Language (VHDL) with further investigation of properties and features of the offered module. The significant advantages of the proposed TPG structure include less area occupied on a chip and higher operation frequency as compared to other solutions. In addition, the design demonstrates good scalability in terms of both the hardware overhead and the length of the generated test sequence.

10

Molecular dialogue between plant resistance pathways – SAR and ISR

Kulbat K., Szczodrowska A.

Biotechnology and Food Science

|

2014

|

Vol. 78, nr 2

129--139

EN

During normal vegetation, plants are exposed to many stress factors, such as the presence of heavy metal ions in the soil, chemical pesticides, excessive UV radiation or pathogenic microorganisms. In response to local infections, plants activate salicylic or jasmonic acid-dependent signaling pathways. Systemic Acquired Resistance (SAR) and Induced Systemic Resistance (ISR) are two forms of induced resistance. The SAR pathway requires the accumulation of endogenous salicylic acid and provides protection against biotrophic pathogens. ISR requires the biosynthesis of jasmonic acid and protects against necrotrophic pathogens. Based on recent scientific research, cross-talk between SAR and ISR signaling pathways is thought to be involved in whole-plant resistance against a wide range of pathogens.

11

Performance and Limitations of VDSL2-based Next Generation Access Networks

Heliotis G., Dimos L.-P., Kordoulis I., Agapiou G.

Journal of Telecommunications and Information Technology

|

2013

|

nr 1

98-102

EN

In this paper, we first briefly review the main operational aspects of FTTC (xPON)/VDSL2 access networks. Then, we present performance measurements with respect to network sub loop operating length and VDSL2 operational profiles (8b, 12a, 17a), studying the rates that can be achieved at different scenarios. We then provide results of the effect of stationary crosstalk and non-stationary impulse noise on the provisioned service in an operating VDSL2 access network.

12

A proposal for 1×8 all-optical switch using multimode interference

Bahrami A., Rostami A.

Optica Applicata

|

2011

|

Vol. 41, nr 1

165--172

EN

We propose an eight-channel all-optical switch using a multimode interference phenomenon. This structure is based on the cooperation of self imaging and self guiding in nonlinear multimode interference. The switching operation is done with changing the intensity of the input signal. To the best of our knowledge, this is for the first time that a 1×8 all-optical switch is presented based on a continuous multimode interference region. Simulation results show low crosstalk and high efficiency in the output profiles. The mean values of the crosstalk and the insertion losses in eight states of the switching operation are -33.8 dB and -0.16 dB, respectively. Full-vectorial beam propagation method is used for the simulation of the device.

13

Impact of Crosstalk into High Resistivity Silicon Substrate on the RF Performance of SOI MOSFET

Ali K. B., Neve C. R., Gharsallah A., Raskin J. P.

Journal of Telecommunications and Information Technology

|

2010

|

nr 4

93-100

EN

Crosstalk propagation through silicon substrate is a serious limiting factor on the performance of the RF devices and circuits. In this work, substrate crosstalk into high resistivity silicon substrate is experimentally analyzed and the impact on the RF behavior of silicon-on-insulator (SOI) MOS transistors is discussed. The injection of a 10 V peak-to-peak single tone noise signal at a frequency of 3 MHz ( fnoise) generates two sideband tones of ?56 dBm separated by fnoise from the RF output signal of a partially depleted SOI MOSFET at 1 GHz and 4.1 dBm. The efficiency of the introduction of a trap-rich polysilicon layer located underneath the buried oxide (BOX) of the high resistivity (HR) SOI wafer in the reduction of the sideband noise tones is demonstrated. An equivalent circuit to model and analyze the generation of these sideband noise tones is proposed.

14

Preliminary evaluation of ER- and AhR-mediated gene expression patterns in rainbow trout (Oncorhynchus mykiss) liver after short-term exposure to zearalenone in binary mixtures

Woźny M., Brzuzan P., Wolińska L., Góra M., Łuczyński M. K.

Environmental Biotechnology

|

2010

|

Vol. 6, No. 1

16-23

EN

While estrogenic properties of mycotoxin zearalenone (ZEA) has been an extensively studied issue, little is known about molecular background of its biological responses that cannot be simply explained by the estrogenic potential. The present study describes effects of ZEA (10mg*kg-1 body weight) in binary mixtures either with benzo[a]pyrene (B[a]P), or with 17β-estradiol (E2) on ER- and AhR-dependent gene expression in juvenile rainbow trout liver, evaluated using Real-Time qPCR. The study revealed dual nature of ZEA, as the treatment with this compound alone increased mRNA levels of both ER- and AhR-mediated gene expression. However, our results did not show any synergistic or additive effect of ZEA in binary mixures with E2 or B[a]P on studied gene expression levels. Whether the intriguing potential of ZEA to elicit distinct signals was a result of binding affinity to AhR or/and ER and AhR mutual receptor interactions, should be investigated in further experiments.

15

SOI Technology: An Opportunity for RF Designers?

Raskin J.-P.

Journal of Telecommunications and Information Technology

|

2009

|

nr 4

3-17

EN

This last decade silicon-on-insulator (SOI) MOS-FET technology has demonstrated its potentialities for high frequency (reaching cutoff frequencies close to 500 GHz for n-MOSFETs) and for harsh environments (high temperature, radiation) commercial applications. For RF and system-onchip applications, SOI also presents the major advantage of providing high resistivity substrate capabilities, leading to substantially reduced substrate losses. Substrate resistivity values higher than 1 k? cm can easily be achieved and high resistivity silicon (HRS) is commonly foreseen as a promising substrate for radio frequency integrated circuits (RFIC) and mixed signal applications. In this paper, based on several experimental and simulation results the interest, limitations but also possible future improvements of the SOI MOS technology are presented.

16

Theoretical analysis of crosstalk between oxygenated and deoxygenated haemoglobin in focal brain-activation measurements by near-infrared topography

Kawaguchi H., Okui N., Sakaguchi K., Okada E.

Opto-Electronics Review

|

2008

|

Vol. 16, No. 4

404-412

EN

The crosstalk between concentration changes in oxygenated haemoglobin and deoxygenated haemoglobin calculated by the modified Lambert-Beer law in near-infrared topography is theoretically investigated. The changes in intensity detected with probe pairs on the scalp caused by the concentration change in either oxygenated or deoxygenated haemoglobin induced by the focal brain activation is predicted by Monte Carlo simulation. The topographic images of the changes in oxygenated and deoxygenated haemoglobin are obtained from the changes in the intensity of light at two wavelengths detected by probe pairs to evaluate the crosstalk. The crosstalk slightly depends on the positional relationship between the probe arrangement and the focal brain activation and is minimised when the focal brain activation is located below a measurement point that is the midpoint between a probe pair. The 690-/830-nm wavelength pair is practically effective for reducing the crosstalk, especially the crosstalk from oxygenated haemoglobin to deoxygenated haemoglobin, in the NIR topography.

17

Effect of bending on transmission characteristics of polymeric arrayed waveguide grating multiplexers

Qin Z.K., Ma C.S., Li D.L., Li H., Zhang D.M., Liu S.Y.

Optica Applicata

|

2008

|

Vol. 38, nr 2

315-327

EN

In terms of the transmission theory of the arrayed waveguide grating (AWG), parameter optimization is performed, and bending effect of arrayed waveguides on transmission characteristics is analyzed for a 33×33 polymeric AWG multiplexer around the central wavelength of 1550.918 nm with the wavelength spacing of 0.8 nm. Analytical results show that the bending of arrayed waveguides causes the phaseshift of the light propagating in the AWG, results in the shift of the transmission spectrum, and brings about the variation of the crosstalk. For the designed AWG device, the Shift of the transmission spectrum is about 0.01 nm, which is much less than the wavelength spacing of 0.8 nm.

18

Laboratory versus industrial cutting force sensor in tool condition monitoring

Jemielniak K., Balazinski M.

Prace Naukowe Instytutu Technologii Maszyn i Automatyzacji Politechniki Wrocławskiej. Konferencje

|

2000

|

Vol. 76, nr 35

109-116

EN

Research works concerning the utilisation of cutting force measurements in tool condition monitoring usually present results and deliberations based on laboratory sensors. These sensors are too fragile to be used in industrial practice. Industrial sensors employed on the factory floor are less accurate, and this must be taken into account when creating a tool condition monitoring strategy. Another drawback of most of these works is that constant cutting parameters are used for the entire tool life. This does not reflect industrial practice where the same tool is used at different feeds and depths of cut in sequential passes. The paper presents a comparison of signals originating from laboratory and industrial cutting force sensors. The usability of the sensor output was studied during a laboratory simulation of industrial cutting conditions. Instead of building mathematical models for the correlation between tool wear and cutting force, an FFBP artificial neural network was used to find which combination of input data would provide an acceptable estimation of tool wear. The results obtained proved that cross talk between channels has an important influence on cutting force measurements, however this input configuration can be used for a tool condition monitoring system.

19

Effects of interconnection inductances on VLSI circuit performance

Piwowarska E.

Bulletin of the Polish Academy of Sciences. Technical Sciences

|

1998

|

Vol. 46, nr 3

353-361

EN

The inductance of on-chip interconnections is usually neglected in simulation of CMOS circuits behaviour. This assumption becomes not valid for modern technologies with higher frequency and greater parasitic RLC parameters of interconnections. This paper describes briefly the model of interconnection and presents the method for R, L parameter calculating in the range of frequency suitable for VLSI CMOS circuits. The calculated values are used for simulating the inductive effects in IC's. The significance of the on-chip interconnection inductance is discussed.