Impact of 3D Antenna Radiation Patterns on TDOA-Based Wireless Localization of UAVs

Abstract

Next big commercial applications of drones require to fly the drone beyond the visual line of sight (BVLOS). This inevitable ability to fly BVLOS will also necessitate the ability to keep track of the drone's location, in order to ensure successful completion of the intended service. In this context, we explore the fundamental limits of 3D localization of drones in conjunction with the effects of the 3D antenna radiation patterns. Although localization of drone/unmanned aerial vehicle (UAV) is a well-studied topic in the literature, its relationship to the antenna effects remains mostly unexplored. In this paper, we investigate the impact of antenna radiation pattern on the accuracy of time-difference-of-arrival (TDOA)-based localization of the UAV. Specifically, we consider a scenario where a fixed number of radio-frequency (RF) sensors, placed at some known locations on the ground, collect the TDOA measurements from the signals transmitted from the UAV, and estimate the location of the UAV from these observations. In order to study the impact of the antenna effects on the fundamental limits of the TDOA-based positioning scheme, we develop a simple analytical model to approximate the total antenna gains experienced by an air-to-ground (A2G) link, for various orientations of the antennas. We then derive the Cramer-Rao lower bound for the TDOA based localization scheme, for all three combinations of the transmit and the receive antenna orientations: vertical-vertical (VV), horizontal-horizontal (HH), and vertical-horizontal (VH).

A Survey on Radio Frequency based Precise Localisation Technology for UAV in GPS-denied Environment

“…Likewise, the authors in [92] designed a localisation system which successfully implemented the stable control of UAV in GPS-denied environment with measured TDOA and EKF. Sinha et al [93] and de Sousa et al [94] both did related researches for UAV localisation through TDOA. But, not mainly focused on UAV localisation in GPS-denied environment.…”

“…But, not mainly focused on UAV localisation in GPS-denied environment. Sinha et al [93] intended to analyse the impact of 3D Antenna Radiation Patterns through TDOA based localisation for UAV. The authors in [94] mainly concerned the precise localisation of UAV in urban area with a full of NLOS path.…”

A Comprehensive Investigation on Range-free Localization Algorithms with Mobile Anchors at Different Altitudes

“…Experimental results show that the received power is highly dependent on the antenna gain of the line-of-sight (LoS) component in the elevation plane when the antennas are aligned (same orientation). In a work proposed in [17], authors investigate a time difference of arrival (TDoA) based approach for localizing drones taking into account a simple A2G 3D antenna radiation pattern. Experimental results show that accounting for antenna effects makes a significant difference and reveals many important relationships between the localization accuracy and the altitude of the drone.…”

“…Motivations. Considering that the RF algorithms have been around for a long time, that the algorithm tested in [14] on the field uses a drone (i.e., flying MA) brought bad performance, and that the irregularities showed in [15,16,17] are for A2G links, we start thinking that altitude could be one of the main cause of poor results for the algorithm tested in [14] and in general for RF algorithms. Therefore, these considerations motivate us to investigate more concerning the accuracy of RF algorithms at different altitudes and the quality of antennas.…”

UAV-aided Wireless Node Localization Using Hybrid Radio Channel Models

“…The impact of the antenna radiation pattern in A2G channels in a 3D localization system using time-difference-of-arrival (TDOA) measurements has been studied in [17]. However, the authors assume that the radiation pattern of the UAV antenna is known.…”