Characterization of a terahertz wave scanned imaging system for threat detection at standoff distances

Idikut, Firat
Takan, Taylan
Altan, Hakan
A terahertz active scanned imaging system is developed in order to acquire images of various targets at stand-off distances. The images are analyzed with respect to the experimentally obtained beam profile at the target plane using a commercially available mm-wave/terahertz camera. The active scanning system utilizes a heterodyne, continuous wave transceiver unit operating at 340 GHz and 2-D opto-mechanical scanning of the target plane is performed using two large area mirror coupled galvanometers. 340 GHz working frequency allows standoff imaging with adequate resolution with the help of a suitable optical design. Results given here correspond to the imaging of various objects placed at least 120 cm away from the transceiver, with a 5 x cm(2) field of view. Image resolution is about 0.6 cm in the horizontal, 0.3 cm in the vertical direction which was assessed by analyzing the measured beam profiles on the target plane with a commercial mm-wave/terahertz camera.


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Imaging systems based on terahertz waves are becoming an integral part of commercial and military screening applications. In this thesis, the prototype of active scan THz imaging system was constructed for detection of concealed objects at standoff distance longer than 5m. The system was mounted on a platform that can adjust in height, tilt and azimuthal angle. The methods of generation and detection of THz signal are based on Schottky diode rectifiers and Schottky diode mixers. The wavelength of the contin...
340 GHz imaging system for detection of concealed threat objects at 5 meters stand-off distance (Conference Presentation)
A THz active scanned imaging system is developed for detection of concealed threat objects at a stand-off distance of 5 meters. Single pixel, active imaging system utilizes a continuous wave transceiver unit operating at 340 GHz, based on RF components and Schottky diode rectifiers. The transceiver has a heterodyne detection geometry and has 7 mW total power output which is derived from a 3dB directional coupler (25 dB directivity) and a horn antenna. 2D opto-mechanical scanning is performed using two mirro...
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Citation Formats
İ. S. YILDIRIM, V. A. ÖZKAN, F. Idikut, T. Takan, A. B. ŞAHİN, and H. Altan, “Characterization of a terahertz wave scanned imaging system for threat detection at standoff distances,” OPTICAL AND QUANTUM ELECTRONICS, pp. 0–0, 2016, Accessed: 00, 2020. [Online]. Available: