Compact beam scanning 240GHz radar for navigation and collision avoidance

Abstract

Autonomous small robotic platforms require a suite of sensor to navigate and function in complex environment. Due to limited space, onboard power, and processing capability these sensors must be low mass, compact size, low power, and run with minimal processing resources. We are in the process of developing a compact and low-power imaging mmwave radar system for small autonomous robotic platforms operating at Y-band to allow for navigation and obstacle detection in conditions that make the use of passive optical sensors difficult or impossible. The radar system is being fabricated and assembled using silicon micromachining technique with the overall mass of 5 grams, peak power of 200 mW, and operational power of 6.7 mW for one frame per second update rate, field of view of o 25 ± , angular resolution of 2 o , range resolution of 37.5cm, and range of 400m. The beam steering is accomplished by frequency scanning and the range resolution is obtained from the standard FMCW technique utilizing a chirped signal waveform with step discontinuities. This paper will present the overall architecture of this radar system in addition to the phenomenological investigation of scattering from obstacle in indoor environment. It is also shown how radar images taken from indoor scenes can be interpreted and utilized to create the interior layout of a building.

Computer Vision for Micro Air Vehicles

“…The lack of a second axis for scanning lidar is a significant limitation and structured light sensors are ineffective in sunlight. Very compact, electronically beam-steered radar with large maximum range is under development for this application, but again has a single-axis scan [52]. Optical flow can cover a wide field of view and has been used for reactive obstacle avoidance [14,25]; however, this only provides information when the aircraft is moving, and poor estimation of time to collision near the focus of expansion limits the ability to perceive obstacles in the direction of motion.…”

Memory‐augmented cognitive radar for obstacle avoidance using nearest steering vector search

“…Consider the radar range-angle map shown in Figure 3a, formed from a single radar frame (i.e. for time multiplexed transmissions processed according to Equation [6]). The radar is moving within an experiment zone, marked as the black solid line in the figure.…”

“…where Jðr; αÞ is given by Equation (6). The threshold O bs1 can be set at a constant value or dynamically adjusted, as for a constant false alarm rate (CFAR) detector.…”

Hardware Enabled Acceleration of Near-Field Coded Aperture Radar Physical Model for Millimetre-Wave Computational Imaging

“…They are also used for imaging purposes. Imaging at millimetre-waves (mmW) has many applications such as security screening [1][2][3], automotive radars [4,5], coincidence imaging [6], autonomous robotics [7][8][9], remote sensing [10][11][12], and concealed weapon detection [13][14][15]. In comparison to optical modalities, mmW signals can penetrate most optically opaque materials and operate in all-weather conditions.…”