Fixed-Wing UAV Attitude Estimation Using Single Antenna GPS Signal Strength Measurements

Jason Gross,Yu Gu,Matthew Rhudy

doi:10.3390/aerospace3020014

Abstract

This article considers a novel approach to using global positioning system (GPS) signal strength readings and estimated velocity vector for estimating the attitude of a small fixed-wing unmanned aerial vehicle (UAV). This approach has the benefit being able to estimate full position, velocity and attitude states of a UAV using only the data from a single GPS receiver and antenna. Two different approaches for utilizing GPS signal strength within measurement updates for UAV attitude in a nonlinear Kalman filter are discussed and assessed using recorded UAV flight data. Comparisons of UAV pitch and roll estimates against measurements from a high-grade mechanical gyroscope are used to show that approximately 5° error with respect to both mean and standard-deviation on both axes is achievable.

Highlights

The ability to estimate an aircraft’s full position, velocity and attitude (PVA) state vector using only a single global positioning system (GPS) antenna and receiver has several benefits
An important potential use of GPS signal strength based attitude estimation on unmanned aerial vehicles (UAVs) is to provide an information source to warn a user if a GPS receiver is under a spoofing attack, such as those that have been demonstrated on small UAVs [1]
This paper considered UAV attitude estimation based upon GPS signal strength measurements that are compensated for known losses

Summary

Introduction

The ability to estimate an aircraft’s full position, velocity and attitude (PVA) state vector using only a single global positioning system (GPS) antenna and receiver has several benefits. An important potential use of GPS signal strength based attitude estimation on unmanned aerial vehicles (UAVs) is to provide an information source to warn a user if a GPS receiver is under a spoofing attack, such as those that have been demonstrated on small UAVs [1]. In this context, the ability to map GPS signal strength to attitude, or predict the expected signal strength given an known UAV attitude (e.g., from an inertial measurement unit (IMU) ) would provide an additional layer of information for authenticating GPS signals. The availability of GPS-only based attitude estimates double be used as an additional information source within a fault-tolerant estimation algorithm, such as Gu. et al 2016 [5]

Methods

Results

Conclusion