Citation: Sanna, G.; Pisanu, T.; Garau,
S. Behavior of Low-Cost Receivers in
Base-Rover Configuration with
Geodetic-Grade Antennas. Sensors
2022, 22, 2779. https://doi.org/
10.3390/s22072779
Academic Editors: Chris Rizos
and Andrzej Stateczny
Received: 17 February 2022
Accepted: 2 April 2022
Published: 5 April 2022
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Article
Behavior of Low-Cost Receivers in Base-Rover Configuration
with Geodetic-Grade Antennas
Giannina Sanna
1,2,
* , Tonino Pisanu
2
and Salvatore Garau
3
1
Department of Civil, Environmental Engineering and Architecture, University of Cagliari, 09123 Cagliari, Italy
2
National Institute for Astrophysics, Astronomical Observatory of Cagliari, 09047 Selargius, Italy;
tonino.pisanu@inaf.it
3
Poema S.r.l., 09122 Cagliari, Italy; salvatore.garau@poemaonline.eu
* Correspondence: topoca@unica.it; Tel.: +39-070-675-5437
Abstract:
The main goal of this research was to evaluate the performances of the ZED-F9P-Ublox
low-cost GNSS receiver in a base-rover real configuration. We realized a base configuration with two
permanent stations based on the ZED-F9P and two geodetic antennas and the rover configuration
based on another ZED-F9P and an ANN-MB-00-00 Multi-band (L1, L2/E5b/B2I) active GNSS u-blox
antenna. In the calculation of the reference stations, we compared the solutions with the ZED-F9P
receiver and a professional receiver. Comparison showed greater variability in the solutions, but
the coordinate values were in very good agreement. Standard deviations were in the order of a few
millimeters. On the rover side, two car tests were performed in two different environments, one in
an extra-urban environment with a long baseline of approximately 30 km in an open sky area with
varying visibility and shielded locations, the other one in an urban area around a circle approximately
10 km in diameter with the presence of buildings and open sectors. The results of the measurements
were very good, with more than 95% of fixed solutions in real-time and a time to fix on reacquisition
of 1 or 2 s. Moreover, real-time kinematic solutions were in good agreement with the post-processed
ones, showing that less than 5% of differences were above 30 mm in the horizontal component and
100 mm in the vertical component.
Keywords: low-cost GNSS receiver; u-blox ZED-F9P2; network RTK; land-surveying
1. Introduction
Over the past few years, global satellite navigation systems have undergone consider-
able development, both in the space segment and the user segment [
1
]. For the completion
of the BeiDou-3 positioning system, no fewer than 30 satellites were put into orbit within
2.5 years between 2017 and 2020 [
2
]. To date, 110 satellites are operational in the four
navigation systems, of which 99 are currently operational in MEO orbit for worldwide cov-
erage: GPS (29), GLONASS (24), GALILEO (22) and BeiDou (24). The possibility to obtain
the satellite positioning using dozens of visible satellites has, therefore, become a reality
very quickly. On the user segment side, several classes of users have been created, which
need to be distinguished as follows: high volume devices for the consumer market, safety
and liability critical devices, high precision devices, timing devices. GNSS receivers are
continually evolving to offer improved performances tailored to each class but, as reported
in [
3
], there is a trend towards using high-volume devices for professional applications.
Indeed, dual frequency has not only become a strategic choice for high-end devices but is
also entering the mid-range smartphone market.
To the best of our knowledge, at the time of writing, there are only three OEM receivers
on the low-cost market, multi-frequency and multi-constellation: Septentrio SimpleRTK3B
Pro (about 550
€
), Bynav C1-8S (about 225
€
) and u-blox ZED-F9P (
approximately 175 €
).
All three can be used for absolute and relative RTK (Real-Time Kinematic) and NRTK
(Network Real-Time Kinematic) positioning and may replace high-precision devices in
Sensors 2022, 22, 2779. https://doi.org/10.3390/s22072779 https://www.mdpi.com/journal/sensors
