Gorka Rubio-Cidre

3-D High-Resolution Imaging Radar at 300 GHz With Enhanced FoV

We have developed a 3-D high-resolution radar at 300 GHz with a cell resolution of 1×1.6×1.6 cm3 at a standoff distance of 8 m for security applications. The selection of an operating frequency of 300 GHz, a bandwidth of 27 GHz, and a field of view of 50×90 cm2 improves the through-clothes imaging of person-borne concealed objects. The radars antenna design allows single-pixel imaging at a frame rate of two frames per second. A reduction in cost and power consumption and improvements in image quality are additional requirements taken into account in the design of this radar system.

Low-Cost CW-LFM Radar Sensor at 100 GHz

This paper presents a W -band high-resolution radar sensor for short-range applications. Low-cost technologies have been properly selected in order to implement a versatile and easily scalable radar system. A large operational bandwidth of 9 GHz, required for obtaining high-range resolution, is attained by means of a frequency multiplication-based architecture. The system characterization to identify the performance-limiting stages and the subsequent design optimization are presented. The assessment of system performance for several representative applications has been carried out.

DDS-Based Signal-Generation Architecture Comparison for an Imaging Radar at 300 GHz

Submillimeter-wave imaging radars for standoff detection require broadband and fast-switch signal-generation architectures in order to achieve a high-range-resolution and near-video-rate imaging system. The signal generation has a strong influence on the radar image quality, primarily due to the transmitted phase noise. Two direct digital synthesis-based architectures for continuous-wave linear-frequency-modulated signal generation have been fabricated and tested for a high-range-resolution imaging radar at 300 GHz for standoff sensing of person-borne concealed threats. In order to select the signal-generation architecture that ensures the proper operation of the imaging radar with a cost-saving objective, three figures of merit have been used: 1) radar image quality; 2) power consumption; and 3) cost. The impact of the signal-generation architectures on the imaging radar indicates that both architectures present a similar radar performance in terms of radar image quality, although the narrowband direct-digital-synthesis/phase-locked loop scheme is a cost-effective solution compared with the broadband direct-digital-synthesis scheme in order to develop an affordable and energy-efficient high-performance preindustrial radar prototype.

Design and preliminary results of a ground-based cloud profiling radar at 94 GHz

This paper describes a 94-GHz ground-based CW-LFM radar system for cloud monitoring. This system transmits 1 W and the bandwidth is configurable up to 2000 MHz. A two-antenna configuration is used to improve the Tx-Rx isolation and two different antennas are used to avoid parallax errors. An RF characterization of the radar architecture is presented. Lastly, a drone detection experiment and preliminary cloud measurements are carried out to validate the radar operation.

Optimization of a compact THz imaging radar for real-time operation

A summary of obstacles and solutions in the Universidad Politécnica de Madrids CW-LFM (continuous-wave linear frequency modulation) imaging radar towards enabling real-time through-clothes threat detection with a compact system is presented. Image acquisition has been designed to permit a 2 fps (frames per second) video feed, and a newly developed signal-processing and image representation software, run on a mixed CPU-GPGPU (central processing unit general-purpose graphics processing unit) architecture, allows speeds up to 5 fps. Additional hardware modifications have yielded reductions in cost, power consumption, and volume.

Understanding cloud dynamics using a ground-based radar at 94 GHz

This paper presents the analysis of mixed-phase cloud observations in Madrid (Spain) carried out with a 94-GHz ground-based CW-LFM radar system. This analysis is based on the 3D reflectivity profiles and the Doppler spectra. The case of interest occurred on 29th January 2016 when a melting layer at 1 Km, up- and downdrafts and drizzle were detected. This radar can be used to estimate the microphysical composition of the detected mixed-phase clouds.

Characterization of a 300 GHz imaging radar for standoff detection

A complete characterization of a 300 GHz high-resolution imaging radar with large Field of View is carried out in order to optimize its operational parameters. This imaging radar has been designed for standoff detection in security applications. The characterization is focused primarily on the spatial and range resolution. The results show that the imaging radar presents a resolution better than 2 cm. 3D images revealing a threat hidden under clothing validate the imaging radar performance.