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Modern Geomatics Technologies and Applications

Fig.1. Selected Senytinel-3A (S3A) passes over study area (red lines) at the Location of TG station (blue triangle) and
extracted coastal data points

 Satellite Altimetry Data

Sentinel-3A (S3A) mission is designed by GMES (Global Monitoring for Environment and Security) and operating
by ESA (European Space Agency) and EUMETSAT (EUropean organization for the Exploitation of Meteorological
SATellites) launched on February 16, 2016. This satellite carries different sensors including SRAL (Synthetic Aperture
Radar Altimeter) altimeter which includes microwave radiometer to measure wet tropospheric correction also other
instruments to determine precise orbital position. SRAL is operating in Synthetic-aperture radar (SAR) mode with high
reputation pulse frequencies, multi-look tracking and ~300m along-track resolution. Table-1 shows few other characteristics
of S3A mission. S3A is the first mission with fully operate in SAR mode[21]. For this study Level-1 (SR_1_SRA) and
Level-2 (SR_2_LAN) data for 41 cycles from 2016/06/07 to 2019/06/11 over pass numbers 154, 268, 382, 481, 595, 709
have been used.

Table 1 S3A mission’s specifications
Frequency No. PRF
Altitude Inclination Cycle Period Pulse Default Band (GHZ) waveform (KHz)
[km] [°] [Days] Length (ns) Gate#
gate
Ku (13.6)
814.5 98.65 27 3.125 43 128 17.8
C (5.4)

 Tide Gauge Records
Single available Tide Gauge (TG) station in this area is Qeshm TG located at 56.28° latitude and 26.95° longitude and
the data records are between 2017/03/06 to 2017/10/10.

3. Methodology

 Satellite Altimetry Principles
Altimeter transmits a pulse with a known power at the speed of light (C) towards the sea surface and receives the
reflected pulse through which the two-way travel time (Δt) is determined, yielding the range (R).

3