Power line characterization from an airborne data collection with a millimeter wave radar

Abstract

Enhancing the operational safety of small, maneuverable rotorcraft has been a critical consideration in the development of next generation situational awareness sensor suites. From landing assistance to target detection and obstacle avoidance, millimeter wave radars have become the leading candidate for such solutions due to their ability to operate in degraded visual environments, whether it is weather, induced debris, or night conditions that must be dealt with. Power lines pose arguably the largest safety risk for helicopter operation due to their difficulty in detection and proper identification to support avoidance maneuvering, where even under perfect conditions they can be nearly invisible to the naked eye. The backscatter phenomenology from braided power lines has been well-studied and formulated in previous literature, albeit mainly in controlled laboratory settings or limited field trials. Subsequently, the ability to simply detect power lines at operational distances up to around 2 km has been demonstrated. In this work, an analysis is performed on the measureable characteristics of power lines captured in a representative operational environment for helicopters. The test location included a diverse set of power line configurations with surrounding ground and tower clutter, representing a realistic scenario. A radiometrically calibrated w-band real-beam FMCW sensor allows the study and estimation of target RCS, as well as evaluation against the developed theory. All analysis is performed on dynamically captured data from a helicopter, where platform dynamics and system stability also play a significant role in a processed result. Results from this work will aid the effective development of next generation situational awareness systems.

Scattering Characteristics of Ultra-High-Voltage Power Lines in Spaceborne Sar Images

“…In recent years, a variety of sensors have been exploited to remotely inspect power lines, such as camera and video devices carried by unmanned aerial vehicles [2] or low-Earth-orbiting satellites [3], airborne light detection and ranging systems [4], and airborne millimeter-wave radars [5]. As an active microwave imaging sensor, synthetic aperture radar (SAR) can provide high-resolution images for wide-area monitoring in all-day and all-weather conditions, which makes it particularly interesting for applications like remote sensing of transmission lines in adverse weather conditions [6].…”

Enabling Technologies for High Performance Millimetre and Sub-millimetre Wave Radar

“…Applications for radars at these frequencies are very diverse and include security screening [1], material inspection [2], helicopter powerline detection and brownout collision avoidance [3], [4], and atmospheric sensing [5], [6]. The successful realisation of sub/millimetre wave radars depends on the availability of enabling technology.…”