Interferometric focusing for the imaging of humans

A Study on Millimeter-Wave Imaging of Concealed Objects: Application Using Back-Projection Algorithm

“…For this purpose,various researchers have demonstrated both passive and active imaging systems [9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27]. Passive imaging systems are based on the detection of natural radiation from the targets and reflection from the environment [9][10][11][12] and hence mostly limited to outdoor missions.…”

“…Besides, the lack of range information in the provided two-dimensional (2D) images puts an additional limit on the detection problem. On the other hand, active imaging systems [13][14][15][16][17][18][19][20][21][22][23][24][25][26][27] exploit various radar systems giving rise to indoor operation as well as sharp range resolving ability. Hence, the position and shape of the concealed objects can be attained from the produced threedimensional (3D) images.…”

“…The active imaging, though, faces some challenges in fulfilling the vital requirements such as fast scanning of the whole body from all aspects and accurate imaging of the acquired near-field data. For this reason, various studies have been focused on the different scanning set-ups along with the consideration of the appropriate near-field reconstruction algorithms [21][22][23][24][25][26][27]. In [21], Sheen et al, originally adapted planar scanning aperture and 3D range migration algorithm (RMA) for imaging the human body.…”

“…Although RMA seems to be the conventional imaging technique, it comes with a difficult implementation for the bistatic configuration [29] of which usage may be favorable to increase the detection capabilities. As an alternative, the back-projection algorithm that is directly applicable to any data collection geometry has been recently employed in a few studies of the concealed object detection problem [25][26][27]. In these studies, both the monostatic [25] and the bistatic [26] imaging performances were investigated for the cylindrical reconstruction surface.…”

FMCW radar near field three-dimensional imaging

“…Currently, millimeter-wave imaging systems are being considered for use at security checkpoints [1]- [3]. A 3-D imaging system [4]- [7] can reveal the target details in all the three spatial dimensions, which is better for target recognition than a 2-D imaging system.…”