scholarly journals Very compact UWB antenna with group delay improvement

2015 ◽  
Vol 12 (2) ◽  
pp. 197-204 ◽  
Author(s):  
Esmaeel Tahanian ◽  
Hamidreza Hasani
Keyword(s):  
Time Domain ◽  
Return Loss ◽  
Group Delay ◽  
Frequency Characteristics ◽  
Back Side ◽  
Antenna Gain ◽  
Uwb Antenna ◽  
Delay Variations ◽  
The Time Domain

In this paper, very compact (12mm?17mm) and simple UWB antenna is proposed. The achieved bandwidth of the presented antenna is from 3.05 GHz to 12.5 GHz and in the most of the bandwidth, the return loss is less than -20dB. In addition to frequency characteristics, time characteristics such as group delay variations for three different antenna positions, namely, front to front, back to back and side by side using CST MW studio are simulated and discussed. To improve the group delay variations, by changing the radius of the circle on the back side of the antenna, the antenna gain in different frequencies will be tuned, therefore, the time domain characteristics of the proposed antenna are greatly improved.

Experimental study of UWB antenna in the time domain

2005 ◽  
Vol 47 (6) ◽  
pp. 554-558 ◽  
Author(s):  
Sung S. Lee ◽  
Sang S. Choi ◽  
Jong K. Park ◽  
Kyoung R. Cho
Keyword(s):  
Experimental Study ◽  
Time Domain ◽  
Uwb Antenna ◽  
The Time Domain

scholarly journals Compact Integrated Bluetooth UWB Antenna with Quadruple Bandnotched Characteristics

2015 ◽  
Vol 5 (6) ◽  
pp. 1433
Author(s):  
Rekha P Labade ◽  
Shankar B Deosarkar ◽  
Narayan Pisharoty
Keyword(s):  
Time Domain ◽  
Group Delay ◽  
Directional Pattern ◽  
Good Time ◽  
Uwb Antenna ◽  
Half Wavelength ◽  
Quarter Wavelength ◽  
Uwb Applications

In this paper,a compact printed dualband antenna for Bluetooth and UWB applications with WiMax(3.3-3.7 GHz), C-band satellite downlink(3.7-4.2GHz), WLAN(5.15-5.825GHz) and DSRC(5.5-5.925GHz) bandnotched characteristics is proposed and investigated. By etching two half-wavelength L-shaped slots in the radiating patch and an inverted U-shaped slot in the microstrip feedline quadruple bandnotched characteristics is obtained. Further, by embedding quarter wavelength parasitic strip at two edges of U-shaped radiating patch dualband characteristics with desired bandwidth is obtained. the proposed antenna is designed and fabricated on a FR4 substrate of dimensions 24mm X 35mm that operates over a 2.4-11GHz with S11<-10dB except over notch bands of 3.3-3.7GHz, 3.7-4.2GHz,5.15-5.625GHz and 5.625-6GHz. Directional pattern in E-plane and nearly omnidirectional pattern in H-plane are observed over a UWB band except at desired bandnotched freqencies. Less variation in group delay and pulse deformation shows good time domain characteristics. In addition, the structure exhibits stable gain over the desired band.

scholarly journals Introduction to the method of estimating time-domain response based on amplitude-frequency characteristics

2021 ◽  
Vol 2087 (1) ◽  
pp. 012061
Author(s):  
Mingrui Wang ◽  
Mei Xu ◽  
Jiangfeng Wang ◽  
Yingying Guo
Keyword(s):  
Research And Development ◽  
Time Domain ◽  
Electromagnetic Pulse ◽  
Parametric Modeling ◽  
Frequency Characteristics ◽  
Practical Applications ◽  
Time Domain Response ◽  
The Time Domain ◽  
Non Parametric

Abstract How to use the amplitude-frequency characteristics to reconstruct the signal to obtain the time-domain response has always been a concern in the field of nuclear electromagnetic protection. So far, in practical applications, parametric modeling and non-parametric modeling have been used to solve related problems. This article summarizes the research and development of using amplitude-frequency characteristics to recover time-domain signals in the field of nuclear electromagnetic pulse protection, and briefly introduces the shortcomings of the two methods in combination with specific experiments.

Investigation on the effects of resistive loading on wrapped bow-tie antennas

2019 ◽  
Vol 11 (4) ◽  
pp. 390-400 ◽  
Author(s):  
Doojin Lee ◽  
George Shaker ◽  
William Melek
Keyword(s):  
Numerical Analysis ◽  
Time Domain ◽  
Group Delay ◽  
Transmission Loss ◽  
Flexible Substrate ◽  
Resistive Loading ◽  
Communication Ability ◽  
Radar Applications ◽  
The Time Domain ◽  
Bow Tie

AbstractThe pulse radiating characteristic of a wrapped bow-tie antenna (WBA) and wrapped resistively loaded bow-tie antenna (WRLBA) is presented for impulse radar applications in this paper. The numerical analysis of the WRLBA is performed by comparing that of the WBA. The wrapped antennas are realized on a flexible substrate. The antennas are fed by an impedance tapered balun, which has an overall transmission loss of −1.4 dB over the balun length. The characteristics of the resistive loading to the wrapped antenna, such as reflection coefficient, reflected pulse in the time domain, voltage standing wave ratio, and input impedance, are experimentally investigated and compared with simulated results. The fidelity factor of the radiated electric field on the boresight direction for the WBA and WRLBA is calculated as 0.82 and 0.96, respectively. The wireless communication ability is evaluated by the transmission coefficient, group delay, boresight gain, and received waveform. The calculated fidelity factor of the received waveform for the WBA and WRLBA is 0.79 and 0.85, respectively. The average and variations of the group delay of both wrapped antennas are observed to be around 2.5 ns and less than 1.5 ns, respectively.

NUMERICAL FREQUENCY RESPONSE ANALYSIS OF SWITCHING CONVERTERS BEHAVIORAL MODELS

2019 ◽  
Author(s):  
Aleksey Shkolin
Keyword(s):  
Time Domain ◽  
Nonlinear Dynamic ◽  
Frequency Characteristics ◽  
Response Analysis ◽  
Switching Converters ◽  
Behavioral Models ◽  
Pulse Converter ◽  
Signal Mode ◽  
The Time Domain ◽  
Simulated Object

This work is devoted to a method for numerically determining the frequency characteristics when modeling nonlinear dynamic objects, in particular during behavioral modeling of pulse converter circuits. The analysis of existing methods for modeling the frequency characteristics of pulse converters is carried out. A technique is given for reducing the amount of calculations when calculating the frequency characteristics of models of nonlinear dynamic pulse systems in the field of their stability based on a calculation in the time domain. This allows one to take into account the essential features of the studied nonlinear objects, in contrast to the linearized models applicable only to the small signal mode. The method is based on the use of correlation analysis when finding the steady-state stationary motion of the simulated object in the time domain while varying the frequency of the harmonic input signal. The results of modeling using the proposed approach are presented.

scholarly journals The Choice of Evaluation Vibration Car Security

2019 ◽  
pp. 1-14
Author(s):  
L. F. Zheglov ◽  
A. B. Fominykh
Keyword(s):  
Dynamic System ◽  
Frequency Domain ◽  
Time Domain ◽  
Vibration Isolation ◽  
Frequency Characteristics ◽  
Road Surface ◽  
Statistical Linearization ◽  
Support Surface ◽  
Dirt Road ◽  
The Time Domain

In the presented material of the article the debatable question - a question of a choice of the field of mathematical modeling of system of vibration isolation of the car is considered. It is known that such a problem can be solved in the frequency and time domain. Since the primary vibration isolation system of the car has non-linear elements, the question arises: how does the solution of the linearized dynamic system in the frequency domain correspond to the data of calculations of the accepted indicators in the time domain? The problem is solved with a random kinematic perturbation from the road surface. Therefore, when working in the time domain, it is necessary to pre-select the method of statistical linearization from the known in practice design of automatic control systems.Four methods of statistical linearization, using which calculations were carried out in the frequency domain, are considered. For a similar dynamic system with its initial and statistically linearized nonlinear elements, calculations were carried out in the time domain. It is shown that the first method of statistical linearization is the most adaptive, according to the amplitude-frequency characteristics of the system. Such calculations were carried out for two surfaces corresponding to the cobblestone and dirt road at different speeds of the car.The analysis of the calculated amplitude-frequency characteristics was carried out for the "resonant" speed of motion, at which the greatest manifestation of the system nonlinearity takes place. When driving in this mode, the system significantly increases the probability of losing contact with the tire support surface. This violates the safety of the vehicle and the system is out of the vibration safety analysis area. Especially this phenomenon is observed when driving on a dirt road at a "resonant" speed. The final results of the calculations are separate-frequency and integral parameters. The latter do not give priority in the selection of the area of calculation, provided the safety of the vehicle.Thus, it can be concluded that the adequacy of the calculations in the frequency and time domain under really specified conditions of the vehicle on the corresponding road surface. However, testing of the problem to be solved, for example, by the eigenfrequency vector of a conservative system, is advisable to be carried out in the frequency domain.

scholarly journals Design of a Compact UWB Antenna with Triple Notched Bands Using Nonuniform Width Slots

2017 ◽  
Vol 2017 ◽  
pp. 1-9 ◽  
Author(s):  
Xu Chen ◽  
Feng Xu ◽  
Xu Tan
Keyword(s):  
Return Loss ◽  
Group Delay ◽  
Ground Plane ◽  
Parameter Study ◽  
Physical Parameters ◽  
Uwb Antenna ◽  
Uwb Antennas ◽  
Quarter Wavelength ◽  
Function Group ◽  
Triple Band

A compact printed UWB antenna with triple band-notched characteristics is proposed. Instead of conventional uniform width slots, two pairs of quarter-wavelength length nonuniform width slots are embedded into the radiating patch and the ground plane to achieve triple notched bands at 3.5, 5.5, and 8.1 GHz. A parameter study is performed to examine the effect of widths and lengths of the slots on the band-notched characteristics. It indicates that the centre frequencies and the bandwidth of notched bands can be controlled by tuning the physical parameters of the slots. Frequency domain measurements including return loss, antenna transfer function, group delay, and gain of the proposed antenna have been carried out. Corresponding results demonstrate that compact UWB antennas with multiple notched bands can be obtained by using nonuniform width slots.

scholarly journals A Planar UWB Antenna with Dual Band Rejection Capability Using Double Rotated ESRRs

2018 ◽  
Vol 7 (1) ◽  
pp. 19-24 ◽  
Author(s):  
A. S. Elkorany ◽  
G. T. Ahmed ◽  
D. A. Saleeb
Keyword(s):  
Return Loss ◽  
Group Delay ◽  
Ultra Wideband ◽  
Ring Resonators ◽  
Dual Band ◽  
Uwb Antenna ◽  
Split Ring ◽  
Wireless Applications ◽  
Different Dimensions ◽  
Good Agreement

In this paper, CPW-Fed ultra wideband (UWB) planar monopole antenna (PMA) loaded by double elliptical split ring resonators (ESRRs) for double band-notch characteristics is introduced and examined. Two different ESRRs with different dimensions are printed in the antenna backside to notch two different frequencies. The ESRRs are also rotated and the corresponding return loss effect is examined.  Different notch frequencies can be obtained by varying the ESRRs, dimensions. Two single SRRs are used to notch two frequencies instead of using dual SRR pairs. Two notch frequencies at 5.2 GHz and 6.9 GHz has been obtained to notch WLAN and C-band wireless applications, respectively. A directive radiation pattern in E-plane and omnidirectional radiation patterns in the H-plane could be observed. Also the gain is suppressed in the notch frequencies. The group delay is nearly stable in the UWB frequency range, except at the notch frequencies, which is distorted sharply. So, the proposed antenna is a good candidate for the modern UWB systems. Finite element method FEM and finite integration technique FIT are used to simulate the proposed structures through the usage of Ansys HFSS and CST MWS. Very good agreement between both results has been obtained.

Apodisation in the time domain

1992 ◽  
Vol 2 (4) ◽  
pp. 615-620
Author(s):  
G. W. Series
Keyword(s):  
Time Domain ◽  
The Time Domain
Sign in / Sign up

Export Citation Format

Share Document