A new UWB pulse design method for multiple narrow-band interference and wide-band interference mitigation

A series of experiments was performed to study the upward-spread-of-masking phenomena as it pertains to pure-tone and speech stimuli. In the initial two experiments, three maskers were employed over a 40–60-dB intensity range. They included a wide band (50–5500 Hz), a speech spectrum (50–1000 Hz), and a narrow-band (50–950 Hz) noise. All filter slopes were 48 dB/octave, except for the upper slope of the speech-spectrum noise that was 6 dB/octave. In the first experiment, pure-tone thresholds obtained by a tracking procedure revealed no spread of masking when the wide-band and speech-spectrum maskers were used. Substantial spread-of-masking effects, characterized by nonlinear threshold increments outside the spectrum of the masker, were observed with the narrow-band masker. The second experiment included three types of speech stimuli (PBs, spondees, and synthetic sentences) under the same mask conditions used with the pure tones. Threshold shifts observed for the wide- and speech-spectrum maskers were linear with the masking intensity level. However, increased shifts, attributable to spread of masking, were observed with the narrow band and progressed nonlinearly as a function of the masking level. Finally, two additional experiments, performed with two different narrow-band maskers and spondee words, provided insightful information regarding the effects of the spread of masking on speech stimuli.

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FDTD Computation of Space/Time Integrated Electromagnetic Lagrangian: New Insights on Mutually Coupled Wide-band Antenna Design

10.36227/techrxiv.15000423 ◽

2021 ◽

Author(s):

Debdeep Sarkar ◽

Yahia Antar

Keyword(s):

Electromagnetic Interference ◽

Interference Mitigation ◽

Near Field ◽

Time Integration ◽

Wide Band ◽

Space Time ◽

Ultra Wideband ◽

Mimo Antennas ◽

Electric And Magnetic Fields ◽

Spatio Temporal

In this paper, we develop a formalism based on either spatially or temporally integrated electromagnetic (EM) Lagrangian, which provides new insights about the near-field reactive energy around generic antennas for arbitrary spatio-temporal excitation signals. Using electric and magnetic fields calculated via FDTD technique and interpolation routines, we compute and plot the normalized values of space/time integrated EM Lagrangian around antennas. While the time-integration of EM Lagrangian sheds light onto the spatial distribution of inductive/capacitive reactive energy, time-variation of spatially integrated EM Lagrangian can help in design of ultra-wideband (UWB) MIMO antennas with low mutual coupling. The EM Lagrangian approach can assist in design of energy harvesting and wireless power transfer systems, as well as for electromagnetic interference mitigation applications.

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Full-Spectrum k-Distribution Model for Radiation in Gas Based on Multi-Group Methods

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1008-1009.839 ◽

2014 ◽

Vol 1008-1009 ◽

pp. 839-845

Author(s):

Yue Zhou ◽

Qiang Wang ◽

Hai Yang Hu

Keyword(s):

Narrow Band ◽

Wide Band ◽

Distribution Model ◽

Full Spectrum ◽

Distribution Method ◽

One Dimensional ◽

Group Methods ◽

Monotonically Increasing Function ◽

Homogeneous Media ◽

Increasing Function

The k-distribution method applied in narrow band and wide band is extended to the full spectrum based on spectroscopic datebase HITEMP, educing the full-spectrum k-distribution model. Absorption coefficents in this model are reordered into a smooth,monotonically increasing function such that the intensity calculations are performed only once for each absorption coefficent value and the resulting computations are immensely more efficent.Accuracy of this model is examined for cases ranging from homogeneous one-dimensional carbon dioxide to inhomogeneous ones with simultaneous variations in temperature. Comparision with line-by-line calculations (LBL) and narrow-band k-distribution (NBK) method as well as wide-band k-distribution (WBK) method shows that the full-spectrum k-distribution model is exact for homogeneous media, although the errors are greater than the other two models. After dividing the absorption coefficients into several groups according to their temperature dependence, the full-spectrum k-distribution model achieves line-by-line accuracy for gases inhomogeneous in temperature, accompanied by lower computational expense as compared to NBK model or WBK model. It is worth noting that a new grouping scheme is provided in this paper.

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Efficient Multirate Filtering

Multirate Systems ◽

10.4018/978-1-930708-30-3.ch004 ◽

2002 ◽

pp. 105-142 ◽

Cited By ~ 3

Author(s):

Ljiljana D. Milic ◽

Miroslav D. Lutovac

Keyword(s):

Digital Filter ◽

Filter Design ◽

Narrow Band ◽

Sampling Rate ◽

Wide Band ◽

Digital Filter Design ◽

Iir Filter ◽

Design And Implementation ◽

Sampling Rate Conversion ◽

Rate Conversion

Application of multirate techniques to improve digital filter design and implementation are considered in this chapter. FIR and IIR filter design and implementation for sampling rate conversion by integer and rational factors are presented. Sharp narrow-band and wide-band multirate design techniques are discussed. Accurate designs of FIR and IIR half-band filters are described in detail. Several examples are provided to illustrate the multirate approach to filter design.

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Narrow-band frequency selective fabrics: simulation and experiment results

Textile Research Journal ◽

10.1177/0040517519832844 ◽

2019 ◽

Vol 89 (19-20) ◽

pp. 4272-4281

Author(s):

Fuwang Guan ◽

Zhaole Li ◽

Zhuli Yang ◽

Chuyang Zhang ◽

Yiping Qiu

Keyword(s):

Narrow Band ◽

Design Method ◽

Simulation Software ◽

Transmission Characteristics ◽

Transmission Method ◽

Band Frequency ◽

Simulation And Optimization ◽

Simulation And Experiment ◽

Frequency Selective ◽

High Consistency

In this paper, frequency selective fabrics (FSFs) with narrow-band transmission characteristics were proposed. The square-ring FSF was taken as an instance to illustrate the design principle. Based on the existing theoretical basis and by means of software simulation and optimization, the optimum structures with ideal narrow-band band-stop or band-pass characteristics were obtained. Then, the practical specimens were manufactured through a computer-based carving process and measured using the transmission method in an anechoic chamber. Two structural models were respectively simulated using two different algorithms and the results showed very small differences, primarily verifying the effectiveness of the design methods and reasonability of the model simplification. The measured and simulated transmission characteristics of square-ring FSFs were compared and showed a high consistency, which further verified the validation of the design method. The other two kinds of FSFs, namely Jerusalem-shaped and circle/ring hybrid FSFs, were designed and measured, which showed the narrow-band frequency selective characteristics were quite ideal. This indicates that the proposed design method using simulation software may be applied to many different structures and has directive sense in the related product design and development process.

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