RCS measurement at terahertz waves for cylinders with different surface roughness

Abstract

The radar cross-section (RCS) measurements for cylinders with different surface roughness have performed in the terahertz bands. The terahertz radar system has 220 and 440 GHz carrier frequencies. It is a solid-state system whose base band signal is generated by a phasor network analyser. The original recorded data are calibrated by the results of the smooth surface cylinder. These calibrated RCS results are compared with calculated results. The experiments suggested that targets with the rough surface will provide complicated scattering in terahertz. The results of this experiment can prove that the surface roughness of the target has a certain impact on RCS measurement results in the terahertz band.

Opportunities and challenges in RCS measurement of 9‐mm bullet model with 77 GHz mmwave COTS radar systems

“…The Ref. 8 reports a study for determination of RCS of cylinders in terahertz frequency range. The RCS is evaluated as a function of surface smoothness and it is found, as expected, that observed RCS increases as surface roughness increases.…”

“…IEEE Std 1502‐2007 7 is the current applicable version of document for RCS measurements which is a comprehensive source even for new entrants in this field. The usual practice for RCS measurement is the use of VNA for collection of frequency domain data and conversion of this data into time domain data by IFFT 7,8 . However, in this article, we have used the complex inphase‐quadrature (I/Q) data at intermediate frequency (IF) stage from the built‐in 16‐bit analog to digital converter (ADC) in COTS radar transceiver chip.…”

“…The usual practice for RCS measurement is the use of VNA for collection of frequency domain data and conversion of this data into time domain data by IFFT. 7,8 However, in this article, we have used the complex inphase-quadrature (I/Q) data at intermediate frequency (IF) stage from the built-in 16-bit analog to digital converter (ADC) in COTS radar transceiver chip. During the offline post processing, this data is used to build the radar data cube and the 256-point FFT is obtained F I G U R E 1 Solid model views and major dimensions of the bullet model [Color figure can be viewed at wileyonlinelibrary.com] F I G U R E 2 Suspended 9-mm bullet model for RCS measurement against the fast-time dimension to calculate the range profile.…”

Improvement in SNR by Adaptive Range Gates for RCS Measurements in the THz Region

“…This is highly preferred in high-resolution radar imaging [11][12][13][14]. Meanwhile, due to the shortened wavelength of THz radiation, the contribution of the fine structure of the targets, such as surface roughness, can no longer be ignored [15,16]. This provides new insights regarding scattering mechanism studying.…”