In Situ Microwave Sensors and Switching Circuit for Oil Slick Thickness Measurement

Abstract

The measurement of oil slick thickness, although at an early stage, has immense applications in determining the extent and quantity of crude oil accidentally discharged in oceans. In this work, we present the design, development and measurement of sensors and switching circuit that were integrated to form a novel microwave oil spill sensor for the determination of oil slick thickness. We used four ultra-wideband polydimethylsiloxane encapsulated antenna-sensors in a cuboid configuration connected to a customised RF switching circuit comprising of two single pole double throw (SPDT) switches. Each of the SPDT switches were connected to two antennas and a port of the vector network analyser (VNA). We developed an android application on a smartphone to select each of the antenna-sensors for the oil slick thickness measurements. The four antenna-sensors operated in the radiating near-field regions. Crude oil has lower density compared to salted seawater, therefore, it floats on the surface. This enabled the four-sensor antenna array to establish the oil thickness using radio frequency. The simulated and measured transmission coefficients showed the capability of the oil slick measurement sensor and switching circuit to determine the oil slick thickness using a novel contact-based in situ microwave approach.

Recent Advances in Oil-Spill Monitoring Using Drone-Based Radar Remote Sensing

“…This technique is not remote-based and should be used after the detection of oil spills. [61] develops a novel microwave oil spill sensor to determine the thickness in the range of 10s mm using an ultra-wideband radar operating between 0.3 and 3000 MHz. The performance of the system is tested under static experimental conditions.…”

Improving the Efficiency of Radar Method for Monitoring Oil Spills on the Water Surface through the Use of an Active Antenna Array and Cosecant-squared Pattern

“…The directional diagram of such an antenna allows you to get the desired form of coverage on the angle of location, at which the received power does not depend on the range of the target at a constant target height. This achieves a greater uniformity of signal level at the receiver input when the target is moving at a constant height within the beam [12][13][14].…”

“…All processes of mathematical modelling were made with the help of PTC Mathcad Express Prime 8.0.0.0. In the beginning there were written basic and auxiliary formulas for the construction of the cosecant diagram (11)(12)(13)(14)(15)(16). (16) Such basic parameters of the radar for radio signal formation as power, frequency and wavelength were taken from a real existing prototype -the Zhuk-A (Figure 4).…”