<title>X-band ISAR imagery of scale-model tactical targets using a wide-bandwidth 350-GHz compact range</title>

Compact quintuple notched-band UWB BPF with high selectivity and wide bandwidth

International Journal of Microwave and Wireless Technologies ◽

10.1017/s1759078720001348 ◽

2020 ◽

pp. 1-7

Author(s):

Lei Bai ◽

Yiqi Zhuang ◽

Zhibin Zeng

Keyword(s):

Closed Loop ◽

High Selectivity ◽

Bandpass Filter ◽

Ultra Wideband ◽

Wide Bandwidth ◽

Fractal Curve ◽

Transmission Zeros ◽

Notched Band ◽

X Band ◽

Stepped Impedance Resonator

Abstract In this paper, a compact quintuple notched-band ultra-wideband bandpass filter with high selectivity and wide bandwidth is proposed. The filter adopts an approximate closed-loop C-shaped stepped impedance resonator to generate triple notched bands, and uses Hilbert fractal curve slit and L-shaped resonator to create single notched band, respectively. Multiple notched-band are centered at 5.29, 6.61, 7.92, 8.95, and 9.93 GHz to eliminate undesired interference from coexisting wireless services of WLAN, C-band, and X-band. Additionally, two transmission zeros are introduced to enhance the sharp skirt selectivity up to 0.944. This filter could exhibit high sharp selectivity and wider bandwidth simultaneously. The filter is fabricated on a RT/Duroid 5880 substrate (ɛ r = 2.2 and thickness = 0.787 mm) and measured to verify the simulation results. Both simulation and measurement are in well agreement, showing the good performance of the filter.

Download Full-text

Features of X-Band Radar Backscattering Simulation Based on the Ocean Environmental Parameters in China Offshore Seas

Sensors ◽

10.3390/s18082450 ◽

2018 ◽

Vol 18 (8) ◽

pp. 2450 ◽

Cited By ~ 1

Author(s):

Tao Wu ◽

Zhensen Wu ◽

Jiaji Wu ◽

Gwanggil Jeon ◽

Liwen Ma

Keyword(s):

Wind Speed ◽

Relative Error ◽

Wave Spectrum ◽

Environmental Parameters ◽

Reanalysis Data ◽

Practical Significance ◽

Scale Model ◽

Wind Speeds ◽

Wave Parameters ◽

X Band

The X-band marine radar has been employed as a remote sensing tool for sea state monitoring. However, there are few literatures about sea spectra considering both the wave parameters and short wind-wave spectra in China Offshore Seas, which are of theoretical and practical significance. Based on the wave parameters acquired from the European Centre for Medium-Range Weather Forecasts reanalysis data (ERA-Interim reanalysis data) during 36 months from 2015 to 2017, a finite depth sea spectrum considering both wind speeds and ocean environmental parameters is established in this study. The wave spectrum is then built into a modified two-scale model, which can be related to the ocean environmental parameters (wind speeds and wave parameters). The final results are the mean backscattering coefficients over the variety of sea states at a given wind speed. As the model predicts, the monthly maximum backscattering coefficients in different seas change slowly (within 4 dB). In addition, the differences of the backscattering coefficients in different seas are quite small during azimuthal angles of 0° to 90° and 270° to 360° with a relative error within 1.5 dB at low wind speed (5 m/s) and 2 dB at high wind speed (10 m/s). With the method in the paper, a corrected result from the experiment can be achieved based on the relative error analysis in different conditions.

Download Full-text

Fully polarimetric W-band ISAR imagery of scale-model tactical targets using a 1.56-THz compact range

10.1117/12.438216 ◽

2001 ◽

Cited By ~ 8

Author(s):

Thomas M. Goyette ◽

Jason C. Dickinson ◽

Jerry Waldman ◽

William E. Nixon ◽

Steve Carter

Keyword(s):

Scale Model ◽

W Band ◽

Compact Range

Download Full-text

X-band ground-based radiometer-scatterometer measuring system

10.1117/12.319480 ◽

1998 ◽

Author(s):

Chuanliang Yao ◽

Yinlong Zhao ◽

Jun Zhang ◽

Zhen-he Fang

Keyword(s):

Measuring System ◽

Title X ◽

X Band

Download Full-text

Microwave heat treated ferrite based X-band microwave absorber with wide bandwidth for low observable applications

2017 IEEE Asia Pacific Microwave Conference (APMC) ◽

10.1109/apmc.2017.8251461 ◽

2017 ◽

Author(s):

Ravi Panwar ◽

Dharmendra Singh

Keyword(s):

Microwave Absorber ◽

Wide Bandwidth ◽

Heat Treated ◽

X Band ◽

Microwave Heat

Download Full-text

Fully Polarimetric W-Band ISAR Imagery of Scale-Model Tactical Targets Using a 1.56THz Compact Range

10.21236/ada461895 ◽

2001 ◽

Author(s):

Thomas M. Goyette ◽

Jason C. Dickinson ◽

Jerry Waldman ◽

William E. Nixon ◽

Steve Carter

Keyword(s):

Scale Model ◽

W Band ◽

Compact Range

Download Full-text

X-band "peeled" HEMT amplifier

10.1117/12.137719 ◽

1992 ◽

Cited By ~ 1

Author(s):

Paul G. Young ◽

Robert R. Romanofsky ◽

Samuel A. Alterovitz ◽

Edwyn D. Smith

Keyword(s):

Title X ◽

X Band

Download Full-text

Wideband Waveform Generation Using MDDS and Phase Compensation for X-Band SAR

Remote Sensing ◽

10.3390/rs12091431 ◽

2020 ◽

Vol 12 (9) ◽

pp. 1431 ◽

Cited By ~ 1

Author(s):

Kyeong-Rok Kim ◽

Jae-Hyun Kim

Keyword(s):

High Resolution ◽

Integrated Circuits ◽

High Speed ◽

Phase Error ◽

Waveform Generator ◽

Wide Bandwidth ◽

Waveform Generation ◽

Area Of Interest ◽

X Band ◽

Hardware Structure

This study investigated wideband waveform generation using a field programmable gate array (FPGA) for X-band high-resolution synthetic aperture radar (SAR). Due to the range resolution determined by the bandwidth, we focused on wide bandwidth generation while preserving spectrum quality. The proposed method can generate wide bandwidth using a relatively low system clock. The new approach was designed in Simulink and implemented by very-high-speed-integrated-circuits hardware description language (VHDL). We also proposed a hardware structure in accordance with the proposed method. Signal connections of FPGA and digital analog converter (DAC) are described in the design of the proposed hardware structure. The developed X-band waveform generator using the proposed method output the desired pulse waveform. For the reduction of phase error and improvement of spectrum quality at the X-band, phase error compensation and pre-distortion were applied to the waveform generator. The results of the simulation and the hardware output demonstrate that the variation and standard deviation of the phase error were improved within the frequency spectrum. Accordingly, the proposed method and the developed waveform generator have the potential to produce a high-resolution image of the area of interest.

Download Full-text