Phased array radio system aided inertial navigation for unmanned aerial vehicles

Abstract

Two of the major challenges with beyond visual line of sight (BVLOS) operations for unmanned aerial vehicles (UAVs) today are navigation and communication. This paper presents a solution that takes on both problems simultaneously, using a phased array radio system (PARS) both for communication and to aid a micro-electro-mechanical inertial navigation system (INS), estimating position, velocity and attitude. The solution is independent of global navigation satellite system (GNSS) for positioning and highly resistant to malicious sources, such as spoofing and jamming.

Towards a Model Based Sensor Measurement Variance Input for Extended Kalman Filter State Estimation

“…The ability to precisely estimate a robot position, or for the robot to be capable of localising itself within the environment, is a vital topic to consider prior to the integration of such autonomous systems into modern day operations [2]. The ability to assess the effectiveness of such a system is a direct requirement for Beyond Visual Line Of Sight (BVLOS) operation [3]. BVLOS is usually considered at ranges greater at 500 m. However, BVLOS operation may also be considered within short range, enclosed cluttered environments involving buildings or obstructions and/or where transitions between indoor and outdoor environments may occur [4].…”

Field Test Results of GNSS-denied Inertial Navigation aided by Phased-array Radio Systems for UAVs

“…269480, 221666, 250725 and 223254). Corresponding Author: gryte@ieee.org systems utilize electronic beamforming, they also provide the user with information which can be used to deduce position of the UAV radio relative the ground station [6]. This system complements the security vulnerability aspect of GNSS solutions through its high signal-to-noise ratio, its use of encrypted communication, in addition to the aforementioned redundancy as it is independent of GNSS.…”

“…It does, however, require radio line-of-sight, and ordinarily has lower accuracy than GNSS solutions. Horizontal PARSbased position accuracy has typically been reported up to ten times lower than that obtained with the Global Positioning System (GPS) standard position service (SPS) [4], [6], [7], depending on range.…”

“…In the light of advances in small UAVs, and in the imminent dangers of cyber-security and GNSS denial of service, PARS for navigation of small UAVs has been an ongoing research topic by the authors of this paper. Notable previous work include a nonlinear observer for aided INS, using PARS, barometer, compass and and IMU [6], and a robust UAV navigation system using GNSS in combination with PARS, for spoofing detection and mitigation [7].…”

“…This is motivated by the desire to couple estimation error between the translational and rotational kinematics in a single state space, such that cross covariance between all states can be exploited when applying aiding corrections based on the the PARS measurements. Previous flights [6], [7] included long passes over water, and contained outliers presumed to come from radio reflections from the water surface. Motivated by this, the present work investigated if the outliers persists also when flying over land, while extending the navigation system to also include outlier rejection.…”