Influence of wideband interference on the error of shapers based on a limiter-low frequency filter loop

1977 ◽  
Vol 20 (8) ◽  
pp. 1224-1227
Author(s):  
A. S. Glinchenko ◽  
M. K. Chmykh ◽  
S. V. Chepurnykh
Keyword(s):  
Low Frequency ◽  
Frequency Filter ◽  
Wideband Interference ◽  
Filter Loop

A New Capacitance Multiplier Structure with High Multiplication Factor for Ultra-Low-Frequency Filter in Biomedical Applications

2019 ◽  
Vol 29 (07) ◽  
pp. 2050109
Author(s):  
Yan Li ◽  
Yong Liang Li
Keyword(s):  
Biomedical Applications ◽  
Low Frequency ◽  
Multiplication Factor ◽  
Frequency Filter ◽  
Pass Filter ◽  
Low Pass Filter ◽  
Physiological Signal ◽  
Wide Range ◽  
Low Pass ◽  
Capacitance Multiplier

A novel capacitance multiplier is proposed to implement an ultra-low-frequency filter for physiological signal processing in biomedical applications. With the proposed multiplier, a simple first-order low-pass filter achieves a [Formula: see text]3-dB frequency of 33.4[Formula: see text]μHz with a 1-pF capacitance and a 20[Formula: see text]k[Formula: see text] resistance. This corresponds to a multiplication factor of as large as [Formula: see text]. By changing the controlling terminal, the [Formula: see text]3-dB frequency can be tuned in a wide range of 33.4[Formula: see text]μHz–6.3[Formula: see text]kHz.

A Low-Frequency Filter in Inertial Applications

2015 ◽  
Vol 645-646 ◽  
pp. 875-880
Author(s):  
Qiang Li ◽  
Xiao Wei Liu ◽  
Liang Yin ◽  
Jia Jun Zhou
Keyword(s):  
Large Time ◽  
Cutoff Frequency ◽  
Low Frequency ◽  
Frequency Filter ◽  
Time Constants ◽  
Operational Transconductance Amplifiers ◽  
Technical Requirements ◽  
Low Pass ◽  
Transconductance Amplifiers ◽  
Current Shunt

A fourth-order cascade low-pass transconductance capacitor filter is designed, and the coefficients of the filter are calculated. For the implementation of large-time constants the current shunt technique and the current cancellation technique are employed in the operational transconductance amplifiers. The whole filter is simulated in Hspice, the the cutoff frequency is 150.2Hz and the THD of the filter is 65dB, which meet the technical requirements of the inertial applications.

scholarly journals Phononic crystal multi-channel low-frequency filter based on locally resonant unit

2014 ◽  
Vol 63 (2) ◽  
pp. 024301
Author(s):  
Cheng Cong ◽  
Wu Fu-Gen ◽  
Zhang Xin ◽  
Yao Yuan-Wei
Keyword(s):  
Phononic Crystal ◽  
Low Frequency ◽  
Frequency Filter

Stable depth extrapolation of seismic wavefields by a Neumann series

Geophysics ◽  
1998 ◽  
Vol 63 (6) ◽  
pp. 2063-2071 ◽  
Author(s):  
Andrzej Kostecki ◽  
Anna Półchłopek
Keyword(s):  
Low Frequency ◽  
Computation Time ◽  
Neumann Series ◽  
Complex Structures ◽  
Lateral Heterogeneity ◽  
Frequency Filter ◽  
Geological Structures ◽  
Depth Migration ◽  
Frequency Space ◽  
Lateral Variations

Several migration methods fail to work when applied to complex geological structures with strong lateral heterogeneity. The generalized migration in the frequency‐wavenumber (f-k) domain based on a convolution with a slowness- (inverse of velocity) dependent operator is capable of downward continuation of wavefield in media with strong vertical and lateral variations of velocity. Unfortunately, this method, as presented in the literature, is potentially unstable. We propose a new, stable extrapolator based on the solution of the integral Fredholm equation, which describes a one‐way wave equation in the form of a Neumann series. The resulting algorithm of depth migration is implemented in both the frequency‐wavenumber (f-k) and frequency‐space (f-x) domains and takes into account arbitrary lateral gradients of velocity, using a low‐frequency filter (in x-f domain) that is the sum of the power series. The computation time of depth migration by a Neumann series is slightly longer than for split‐step Fourier migration. The examples presented suggest that the depth migration by Neumann’s series method can be used to map complex structures with strong lateral gradients of velocity.

scholarly journals Mechanical low-frequency filter via modes separation in 3D periodic structures

2017 ◽  
Vol 111 (23) ◽  
pp. 231902 ◽  
Author(s):  
L. D'Alessandro ◽  
E. Belloni ◽  
R. Ardito ◽  
F. Braghin ◽  
A. Corigliano
Keyword(s):  
Periodic Structures ◽  
Low Frequency ◽  
Frequency Filter
Sign in / Sign up

Export Citation Format

Share Document