Control of the Flight Vehicle Cable over Wide Spectrum Radiation Effects Simulation Experiment Research

2012 ◽  
Vol 510 ◽  
pp. 141-146
Author(s):  
Yi Lv

According to the aircraft is under complex work hard to electromagnetic environment performance analysis of the issue, a vehicle body and control lead in ultra-wideband high power microwave (UWS-HPM) under the irradiation of coupling effect and experimental study. Use back to lose signal simulator with the repetitive; the change control the length of the wire, radiation orientation, irradiation parts and other measures to make the experiment generality. The results of the study show that: aircraft in more than 25 kV/m of field UWS-HPM irradiation, interference and make its crash. Interference coupling mechanism is energy electromagnetic pulse through the control lead into the control box, and influence the formation of the control order. On the basis of experiment, this paper analyzes the interference with various factors coupling relation, which for electromagnetic protection equipment provides a theoretical basis.

2021 ◽  
Vol 11 (8) ◽  
pp. 3606
Author(s):  
Seonho Lim ◽  
Young Joong Yoon

In this paper, a wideband-narrowband switchable tapered slot antenna (TSA) with a compact meander line resonator for an integrated microwave imaging and hyperthermia system was proposed. A compact meander line resonator, which exhibited band-pass characteristics and provided narrowband characteristics by using one PIN diode, was fabricated beneath the tapered slot of the wideband TSA to minimize the degradation of the wideband characteristics. Moreover, the electromagnetic energy was transferred to the meander line resonator with a coupling effect to ensure effective frequency switching. By adapting a PIN diode on the meander line resonator, frequency switching could be achieved. In this way, the proposed antenna could operate in a real-time frequency switching mode between the ultra-wideband (UWB; 3.1~10 GHz), which is used for microwave imaging, and the 2.45 GHz band (industrial, scientific, and medical, ISM band), which is used for microwave hyperthermia. Frequency and time-domain results proved the applicability of the proposed antenna to an integrated breast cancer detection and treatment system.


Micromachines ◽  
2020 ◽  
Vol 11 (6) ◽  
pp. 558 ◽  
Author(s):  
Ashok Yadav ◽  
Vinod Kumar Singh ◽  
Akash Kumar Bhoi ◽  
Gonçalo Marques ◽  
Begonya Garcia-Zapirain ◽  
...  

A compact textile ultra-wideband (UWB) antenna with an electrical dimension of 0.24λo × 0.24λo × 0.009λo with microstrip line feed at lower edge and a frequency of operation of 2.96 GHz is proposed for UWB application. The analytical investigation using circuit theory concepts and the cavity model of the antenna is presented to validate the design. The main contribution of this paper is to propose a wearable antenna with wide impedance bandwidth of 118.68 % (2.96–11.6 GHz) applicable for UWB range of 3.1 to 10.6 GHz. The results present a maximum gain of 5.47 dBi at 7.3 GHz frequency. Moreover, this antenna exhibits Omni and quasi-Omni radiation patterns at various frequencies (4 GHz, 7 GHz and 10 GHz) for short-distance communication. The cutting notch and slot on the patch, and its effect on the antenna impedance to increase performance through current distribution is also presented. The time-domain characteristic of the proposed antenna is also discussed for the analysis of the pulse distortion phenomena. A constant group delay less than 1 ns is obtained over the entire operating impedance bandwidth (2.96–11.6 GHz) of the textile antenna in both situations, i.e., side by side and front to front. Linear phase consideration is also presented for both situations, as well as configurations of reception and transmission. An assessment of the effects of bending and humidity has been demonstrated by placing the antenna on the human body. The specific absorption rate (SAR) value was tested to show the radiation effect on the human body, and it was found that its impact on the human body SAR value is 1.68 W/kg, which indicates the safer limit to avoid radiation effects. Therefore, the proposed method is promising for telemedicine and mobile health systems.


2021 ◽  
Author(s):  
Fabio Falconi ◽  
Claudio Porzi ◽  
Filippo Scotti ◽  
Giovanni Serafino ◽  
Antonio Malacarne ◽  
...  

Abstract In the last decade, the interest in software-defined ultra-wideband (UWB) and tunable radio frequency (RF) apparatuses with low size, weight, and power consumption (SWaP), has grown dramatically, pushed by the new 6G vision where, RF equipment shall enable a large number of fundamental applications as UWB communications, robot localization mapping and control and high precision radars, all of them contributing in revolutionizing our life style. Unfortunately, the coexistence of ultra-wideband and software-defined operation, tunability and low SWaP represents a big issue in the current RF technologies. In this article, to the best of our knowledge, the first example of a complete tunable software-defined RF transmitter with low footprint (i.e. on photonic chip) is presented exceeding the state-of-the-art for the extremely large tunability range of 0.5-50 GHz without any parallelization of narrower-band components and with fast tuning (<200micros). This first implementation, represents a breakthrough in microwave photonics.


Antennas ◽  
2021 ◽  
Author(s):  
M. M. Ivoylova ◽  
A. V. Kashin ◽  
V. A. Kozlov

The current trend in the development of radio engineering systems (RES) is to use wide spectrum signals, the application of which provides an increase in the resolution and secrecy of the radar operation, an increase in the speed and volume of transmitted information for communication and telemetry systems. The class of such signals includes ultrashort pulses (USP signals), radio pulses with linear frequency modulation (chirp signals). Also of interest are ultra-wideband (UWB) noise signals (UWBN signals), which have high electromagnetic compatibility, stealth and noise immunity. When designing promising ground-based and space-based RES using wide spectrum signals, an important task is to determine the distortions of their envelope shape and distortions of spectrum, as well as the change in the polarization of the emitted wave when passing through the Earth's ionosphere, since taking these distortions into account will provide conditions for optimal reception. This article presents the numerical assessment results of the expected distortions of the wide spectrum signals main types of the decimeter wavelength range, for middle latitudes at heights from 100 km to 1000 km. The conversion of the emitted pulse into a frequency modulated radio pulse is typical for the USP signal. For a chirp radio pulse with a monotonically increasing frequency, an initial decrease in duration with an increase in amplitude and subsequent stretching in time with further spread is typical (the amplitude change is estimated due to a change in the signal shape without taking into account spread). For a chirp radio pulse with a monotonically falling frequency and a UWBN signal, dispersion distortions manifest themselves as an increase in their duration with a decrease in amplitude. For all signal types under consideration that have passed through the ionosphere, a leading edge lag is observed, the dependences of frequency on time at an altitude of 1000 km are repeated and are close to hyperbolic character, the energy spectra envelope shape of the considered signals is almost not distorted. The polarization plane rotation for signals with a spectrum concentrated in the frequency range above 0.7 GHz does not exceed 45


2014 ◽  
Vol 26 (1) ◽  
pp. 13005
Author(s):  
冯菊 Feng Ju ◽  
廖成 Liao Cheng ◽  
刘雪明 Liu Xueming ◽  
张扬 Zhang Yang ◽  
邵浩 Shao Hao

2013 ◽  
Vol 25 (8) ◽  
pp. 2027-2030
Author(s):  
朱四桃 Zhu Sitao ◽  
王俊杰 Wang Junjie ◽  
关锦清 Guan Jinqing ◽  
周金山 Zhou Jinshan ◽  
易超龙 Yi Chaolong ◽  
...  

2018 ◽  
Vol 02 (01) ◽  
pp. 1850009
Author(s):  
Stefan Brüggenwirth ◽  
Fernando Rial

In the paper, we describe a trajectory planning problem for a six-DoF robotic manipulator arm that carries an ultra-wideband (UWB) radar sensor with synthetic aperture (SAR). The resolution depends on the trajectory and velocity profile of the sensor head. The constraints can be modeled as an optimization problem to obtain a feasible, collision-free target trajectory of the end-effector of the manipulator arm in Cartesian coordinates that minimizes observation time. For 3D reconstruction, the target is observed in multiple height slices. For through-the-wall radar the sensor can be operated in sliding mode for scanning larger areas. For IED inspection the spotlight mode is preferred, constantly pointing the antennas towards the target to obtain maximum azimuth resolution. UWB sensors typically use a wide spectrum shared by other RF communication systems. This may become a limiting factor on system sensitivity and severely degrade the image quality. Cognitive radars can adapt dynamically their bandwidth, frequency and other transmit parameters to the radio frequency environment to avoid interference with primary users.


Author(s):  
Gudrun Mikota ◽  
Rainer Haas ◽  
Evgeny Lukachev

Fluid-structure interaction in a bent pipeline is investigated by modal methods. Measured frequency response functions between flow rate excitation and pressure response indicate a coupling effect near the third pipeline resonance. Using modal coordinates for the hydraulic and the mechanical subsystems, a two-degrees-of-freedom study of resonance coupling is carried out. An experimental modal analysis of the coupled hydraulic-mechanical system confirms the predicted resonance splitting; it illustrates the coupling mechanism and shows the relevant mechanical part. An analytical fluid-structure interaction model succeeds in reproducing the measured coupling effect. This model is also used for modification prediction; it demonstrates that an appropriate assembly of mass and damping on the pipeline can help to reduce hydraulic resonance amplitudes.


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