Phase Control in Interpolation for Backprojection of THz FMCW SAR Signals

Ivanenko, Yevhen; Vu, Viet T.; Barowski, Jan; Hellsten, Hans; Pettersson, Mats I.

doi:10.23919/irs54158.2022.9905043

Cited by 2 publications

(3 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The developments in system-on-chip complementary metal oxide semiconductor (CMOS) radio frequency integrated circuits (RFIC) have resulted in the emergence of cost-effective frequency modulated continuous wave (FMCW) millimetre wave radars for imaging applications. The radar imaging systems include multiple input multiple output SAR (MIMO SAR), interferometric SAR (InSAR) and tomographic SAR [22]- [26]. In [8], a THz near-field imaging system based on SAR has been developed for precise, high resolution NDT of packaged aluminium etched antenna arrays and for flexible gold electrode array surface imaging.…”

Section: B Related Workmentioning

confidence: 99%

Curved Synthetic Aperture Radar for Near-Field Terahertz Imaging

Gezimati

Singh

2023

IEEE Photonics J.

View full text Add to dashboard Cite

High resolution imaging technique will play an essential role in the future smart imaging applications to provide potential solutions for accurate detection, monitoring and classification of the target. The potential of synthetic aperture radar (SAR) systems to acquire high resolution images has opened new frontiers and led to its exploration in new applications. The conventional microwave radar imaging suffers limited range resolution in the sub-millimeter wave range and optical imaging methods are constrained by the diffraction limit. In the terahertz (THz) regime of the spectrum, the SAR systems could be operated in all the weather, all the time and are capable of penetrating through clouds, smoke, dust etc. to achieve high resolution images beyond the diffraction limit. The curved SAR presents a SAR system created by circularly encircling the target scene. The Circular SAR and Spiral SAR which are based on a circular and cylindrical spiral scanning trajectory, respectively are the scanning methods used for curved SAR. In this paper, we have explored a new toolbox that enables the rapid development of near-field THz-SAR imaging systems and generation of large near-field THz imaging scenarios with the goal to support and facilitate data driven research such as deep learning in the THz community through synthetically generated SAR images as well as its potential for THz based high resolution and 2D/3D near-field imaging application. Initially, the potential advantages of THz-SAR over Microwave SAR and optical imaging methods are presented. Further, a frequency modulated continuous wave (FMCW) radar testbed is simulated in multi-input multi-output (MIMO) configuration for the target frequency band. Moreover, the circular and cylindrical SAR scanning methods are explored for near-field imaging of point targets to obtain 2D and 3D THz-SAR images, respectively. Also, the radar images are reconstructed using the Back Propagation and Polar Formatting Algorithms, focusing on short range applications like indoor environments. Finally, the SAR performance evaluation metrics are reported and a roadmap for future work is presented.

show abstract

Section: B Related Workmentioning

confidence: 99%

Curved Synthetic Aperture Radar for Near-Field Terahertz Imaging

Gezimati

Singh

2023

IEEE Photonics J.

View full text Add to dashboard Cite

show abstract

“…Different pulse THz SAR testbeds have been developed to perform high-resolution imaging at frequencies starting from 0.22 THz and up to 1.1 THz; see references [1]- [6] for details. Furthermore, THz SAR systems based on FMCW radars operating in different frequency ranges have emerged, e.g., [0.122; 0.17] THz for the system reported in [7], and [0.126; 0.182] THz for the system done in [8], [9].…”

Section: Introductionmentioning

confidence: 99%

“…The major computational burden of the backprojection algorithms is the interpolation procedure, the accuracy of which correlates with the upsampling procedure of the raw data. In [13] and [9], an improved interpolation procedure was introduced to process pulse THz SAR and FMCW THz SAR signals. The developed interpolators provide the opportunity to obtain accurate images without upsampling of raw data.…”

Section: Introductionmentioning

confidence: 99%

Autofocusing of THz SAR Images by Integrating Compressed Sensing into the Backprojection Process

Ivanenko

Pettersson

2023

2023 IEEE Radar Conference (RadarConf23)

Self Cite

View full text Add to dashboard Cite

The THz frequency spectrum provides an opportunity to explore high-resolution synthetic-aperture-radar (SAR) short-range imaging that can be used for various applications. However, the performance of THz SAR imaging is sensitive to phase errors that can be caused by an insuffcient amount of data samples for image formation and by path deviations that can be practically caused by SAR platform vibrations, changes in speed, changes in direction, and acceleration. To solve the former problem, an improved interpolation procedure for backprojection algorithms has been proposed. However, to make these algorithms effcient in handling the latter problem, an additional autofocusing is necessary.In this paper, we introduce an autofocusing procedure based on compressed sensing that is incorporated into the backprojection algorithm. The reconstruction is based on the following calculated parameters: windowed interpolation sinc kernel, and range distances between SAR platform and image pixels in a defned image plane. The proposed approach is tested on real data, which was acquired by the 2πSENSE FMCW SAR system through outdoor SAR imaging.

show abstract

Phase Control in Interpolation for Backprojection of THz FMCW SAR Signals

Cited by 2 publications

References 17 publications

Curved Synthetic Aperture Radar for Near-Field Terahertz Imaging

Curved Synthetic Aperture Radar for Near-Field Terahertz Imaging

Autofocusing of THz SAR Images by Integrating Compressed Sensing into the Backprojection Process

Contact Info

Product

Resources

About