Citation: Luo, J.; Zhang, J.; Yang, H.;
Guan, Y. All-Directional DOA
Estimation for Ultra-Wideband
Regular Tetrahedral Array Using
Wrapped PDoA. Sensors 2022, 22,
1532. https://doi.org/10.3390/
s22041532
Academic Editor: Christian Vollaire
Received: 11 January 2022
Accepted: 10 February 2022
Published: 16 February 2022
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Article
All-Directional DOA Estimation for Ultra-Wideband Regular
Tetrahedral Array Using Wrapped PDoA
Jinglin Luo
1,2,
*, Jingjing Zhang
3
, Haidong Yang
1,2
and Yisheng Guan
4
1
Foshan Nanhai Guangdong Technology University CNC Equipment Cooperative Innovation Institute,
Foshan 528225, China; yanghd@gdut.edu.cn
2
School of Electromechanical Engineering, Guangdong University of Technology, Guangzhou 510006, China
3
School of Mechatronic Engineering and Automation, Foshan University, Foshan 528000, China;
jingjing@fosu.edu.cn
4
Biomimetic and Intelligent Robotics Lab (BIRL), Guangdong University of Technology,
Guangzhou 510006, China; ysguan@gdut.edu.cn
* Correspondence: luojinglinemail@gmail.com
Abstract:
In this paper, we proposed a Regular Tetrahedral Array (RTA) to cope with various
types of sensors expected in Ultra-Wideband (UWB) localization requiring all-directional detection
capability and high accuracy, such as indoor Internet-of-Things (IoT) devices at diverse locations,
UAVs performing aerial navigation, collision avoidance and takeoff/landing guidance. The RTA is
deployed with four synchronized Ultra-Wideband (UWB) transceivers on its vertexes and configured
with arbitrary aperture. An all-directional DOA estimation algorithm using combined TDoA and
wrapped PDoA was conducted. The 3D array RTA was decomposed into four planar subarrays solved
as phased Uniform Circular Array (UCA) respectively. A new cost function based on geometric
identical and variable neighborhood search strategy using TDoA information was proposed for
ambiguity resolution. The results of simulation and numerical experiments demonstrated excellent
performance of the proposed RTA and corresponding algorithm.
Keywords: ultra-wideband; regular tetrahedral array; DOA estimation; wrapped PDoA
1. Introduction
All-directional detection for a single Ultra-wideband (UWB) source in an isotropic way
become increasingly important. It is required in many UWB applications such as single
anchor UWB localization system [
1
], UAVs collision avoidance [
2
–
4
], takeoff/ landing
guidance [
5
,
6
], Internet-of-Things (IoT) devices, and vehicular-to-everything (V2X) commu-
nication [
7
]. Current antenna arrays applied in UWB localization, such as Uniform Circular
Array (UCA), Uniform Linear Array (ULA) [
8
,
9
], have restrictions on their detection angle
range in both azimuth and elevation.
Tiemann et al. [
8
] tested a UWB location system based on three synchronized UWB
transceivers mounted on the helmet for supporting first responders through 3D location of
fellows and victims in a low visibility environment. This antenna array consists of 2 ULAs
perpendicular to each other, for measuring the Angle of Arrival (AoA) in the x-axis and
y-axis respectively, using PDoA [
10
] of antennas. Similarly, Zhao et al. [
9
], tested a low-
power, scalable and cm-accurate UWB location system, based on eight synchronized UWB
transceivers mounted on a single PCB, four antennas in horizontal and other four antennas
in vertical. The common imperfections of these two works are angle range limitation and
fixed antenna spacing less than half-wavelength. The tight antenna spacing is designed
for special frequencies that limit the flexibility of the antenna array. Furthermore, working
at the centimeter band, mutual coupling between antennas disturbs received signals and
degrades the DoA finding performance severely [11].
Sensors 2022, 22, 1532. https://doi.org/10.3390/s22041532 https://www.mdpi.com/journal/sensors
