The Characterization of Phase Center of Multi-band GNSS Antenna and the Design of V2V Antenna, along with Channel Analysis in Rural Propagation Scenarios

Abstract

The wireless communication network has been vastly improved in the past decades. A high-precise positioning system and reliable wireless network has become an essential part of our daily life, especially Cellular Vehicle-to-Everything (C-V2X). It got most benefit development in Telematics Control Unit (TCU) of Vehicle E/E architecture. The TCU is main including the positioning and wireless connectivity. This research work focus on the automotive multi-band GNSS positioning antenna and Vehicle-to-Vehicle connectivity antenna. High-precision Global Navigation Satellite System (GNSS) positioning is a promising technology that will be employed in future automotive navigation systems. This system will comprise the United States' Global Positioning System (GPS), the Russian Federation's Global Orbiting Navigation Satellite System (GLONASS), China Beidou Navigation Satellite System (BDS), and the European Union's Galileo. The significant enhancement in accuracy and precision is achieved through multiband signal transmission, carrier phase correction, and Real Time Kinematic (RTK). However, due to the current limitations of large-sized and expensive survey-grade antenna solutions, widespread adoption of this technology in the automotive sector remains challenging. In Chapter 3, it presents a cost-effective small-sized multi-band ceramic GNSS patch antenna from its design stage to real sample fabrication. Furthermore, an investigation into this patch antenna reveals absolute phas center variation measured within an indoor range for accurate received signal phase error correction. Additionally, the study explores the integration of this low-cost antenna solution into a standard multi-band automotive antenna product. We evaluate this product both independently within an indoor range setting and on a typical vehicle roof at an outdoor range facility. Utilizing these evaluation findings enables us to achieve precise receiver position estimation with minimal phase motion errors. Vehicle-to-Everything (V2X) communications will be an integral component of future autonomous drive decision systems, necessitating the establishment of a robust communication channel between end-to-end devices. However, existing cellular electromagnetic (EM) wave propagation models do not adequately suit V2X direct communication applications due to variations in antenna placement on vehicles. To address this issue, the Chapter 4 focuses on analyzing the propagation channel in a rural Vehicle-to-Vehicle (V2V) scenario for vehicular communication through antenna position experiments at different heights. By employing the ray-tracing algorithm, this research constructs a simulation model for a rural scenario using Commercial-off-the-Shelf (COTS) EM modeling software that calculates path loss received power and delay spread within a given propagation channel. Furthermore, it conducts real-world vehicle measurements to validate our simulation results, which demonstrate good agreement between simulated and measured receiver power. This study considers two types of antennas located at three different relative heights between the two vehicles and provides valuable insights to V2V antenna characteristics, antenna placement, and vehicle communication channel analysis