Frequency, Temperature and Salinity Variation of the Permittivity of Seawater

High performance underwater UHF radio antenna development

“…In published literature, simple empirical formulas are proposed for these parameters [1]. Moreover, a rigorous model based on the electrophysiology of seawater [2] demonstrates an excellent correspondence between simulations and measurements. Unfortunately, the calculation of the rigorous model involves substantial experimental characterization, thus considerably reducing the possibilities of use.…”

“…Fig. 1 illustrates that for standard conditions of underwater medium, variations of predictions between the two models (empirical [1] and rigorous [2]) could induce a significant impact on the attenuation assesment in seawater of electromagnetic waves at around 2.4 GHz frequency.…”

Underwater Wireless Communications in Freshwater at 2.4 GHz

“…That is, the propagation speed and the absorption coefficient remain constant along the frequency spectrum. However, these parameters are affected by the variation of temperature and salinity in seawater [12].…”

A novel liquid antenna for wearable bio-monitoring applications

“…This accelerates the ion transport mechanisms and results in the electrolysis process at the solid/solution interface where O 2 is produced at the anode and H 2 is produced at the cathode. These processes occur at a potential limit that depends on the electrode materials [5][6][7][8][9][10][11] …”

“…At higher frequencies, a reversible faradic process may occurs via charge transfer at the interface (oxide formation and reduction) in addition adsorption and desorption of water ions. Since the polarity alteration of the electrodes must cycle rapidly at some resonant frequency, a reversible electrode process is necessary whereas, in the case of an irreversible process, the alternating potential would result in the accumulation of solids or gasses onto the electrode surface overtime [5][6][7][8][9][10][11].…”