Influence of temperature on signal attenuation at microwaves frequencies underwater

New wireless applications are emerging subsea. Pinless Subsea Connectors (PSC) aim to transfer high-speed data over short distances. They present several advantages in comparison with previous technologies. However, its design presents several challenges that need to be addressed. For PSC based on electromagnetic signaling, one of the principal factors affecting system planning is signal attenuation. This work characterizes the impact of water temperature on signal attenuation in both freshwater and seawater. We present experimental data in the 0.5-3.5 GHz band at two typical values for the water temperature (5 and 22 °C). The study confirms that higher temperatures may help to enlarge system coverage in freshwater. However, the opposite effect is found in seawater. The obtained patterns of attenuation with the temperature are in agreement with the available empirical data. However, we also show that available data bases are not accurate enough for estimating signal attenuation for the presented working conditions.