Abstract
Real-time kinematic (RTK) technique is widely used in modern society because of its high accuracy and real-time positioning. The appearance of Android P and the application of BCM47755 chipset make it possible to use single-frequency RTK and dual-frequency RTK on smartphones. The Xiaomi Mi 8 is the first dual-frequency Global Navigation Satellite System (GNSS) smartphone equipped with BCM47755 chipset. However, the performance of RTK in urban areas is much poorer compared with its performance under the open sky because the satellite signals can be blocked by the buildings and trees. RTK can’t provide the positioning results in some specific areas such as the urban canyons and the crossings under an overpass. This paper combines RTK with an IMU-based pedestrian navigation algorithm. We utilize attitude and heading reference system (AHRS) algorithm and zero velocity update (ZUPT) algorithm based on micro electro mechanical systems (MEMS) inertial measurement unit (IMU) in smartphones to assist RTK for the sake of improving positioning performance in urban areas. Some tests are carried out to verify the performance of RTK on the Xiaomi Mi 8 and we respectively assess the performances of RTK with and without the assistance of an IMU-based pedestrian navigation algorithm in urban areas. Results on actual tests show RTK with the assistance of an IMU-based pedestrian navigation algorithm is more robust and adaptable to complex environments than that without it.
Highlights
Over the past two decades, Global Navigation Satellite System (GNSS) has been evolving rapidly [1]
Some tests are carried out to verify the performance of Real-time kinematic (RTK) on the Xiaomi Mi 8 and we respectively assess the performances of RTK with and without the assistance of an inertial measurement unit (IMU)-based pedestrian navigation algorithm in urban areas
Considering GNSS outage and mechanical systems (MEMS)-IMU integrated into our smartphone, we adopt the Madgwick algorithm, which is one kind of AHRS algorithm to provide the initial attitude of our smartphone and utilize the zero velocity update (ZUPT) algorithm to aid inertial navigation system (INS) to provide positioning results during GNSS outage
Summary
Over the past two decades, GNSS has been evolving rapidly [1]. The U.S government has promoted the Global Positioning System (GPS) modernization program, adding the second civil signal on L2 frequency (L2C) and the third civilian signal on L5 frequency (L5). Google introduced the Android P operating system that could disable duty cycling with the developer option “Force full GNSS measurements” [21] These two changes made precise positioning on smartphones much more promising. With dual-frequency raw measurements, the Xiaomi Mi 8 could use the combination of L1 bands and L5 bands to eliminate most ionosphere errors, which helped obtain more accurate positioning results than smartphones like the. Considering GNSS outage and MEMS-IMU integrated into our smartphone, we adopt the Madgwick algorithm, which is one kind of AHRS algorithm to provide the initial attitude of our smartphone and utilize the ZUPT algorithm to aid INS to provide positioning results during GNSS outage.
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
