High-rate altimetry in SNR-based GNSS-R: Proof-of-concept of a synthetic
vertical array
Abstract
Global Navigation Satellite System Reflectometry (GNSS-R) has emerged as
a promising remote sensing technique for coastal sea level monitoring.
The GNSS-R based on signal-to-noise ratio (SNR) observations employs a
single antenna and a conventional receiver. It performs best for low
elevation satellites, where direct and reflected radio waves are very
similar in polarization and direction of arrival. One of the
disadvantages of SNR-based GNSS-R for sea level altimetry is its low
temporal resolution, which is of the order of one hour for each
independent satellite pass. Here we present a proof-of-concept based on
a synthetic vertical array. It exploits the mechanical movement of a
single antenna at high rate (about 1 Hz). SNR observations can then be
fit to a known modulation, of the order of the antenna sweeping rate. We
demonstrate that centimetric altimetry precision can be achieved in a
5-minute session. [©2021 IEEE]