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Sub-Nyquist signal processing in marine radar.

'Radar' is an acronym derived from the words Radio Detection and Ranging. It is used in maritime civil applications as a navigation aid to avoid collisions. The technique uses short bursts of an emitted electromagnetic wave at high frequency and precise direction. If an object is near the antenna transmitting these bursts, echos are sent back to the antenna. The time between the transmission and the reception of an echo is an indication of the distance between antenna and the object. The received echos (they are mainly changed in frequency and amplified) are processed and then represented on a screen. At the moment, the use of cathode ray tube screens (CRT) is less common than digital screens, so often a digitization is necessary. Therefore the analogue signal must be sampled. In order to correctly reconstruct the signal, at the receiving end the signal has to be sampled at a rate higher than the Nyquist frequency. This limit is generally accepted as a constraint for the cost and performance of radar systems in general. Making use of some recent results in exponential analysis developed at UAntwerpen, it is possible to break the Nyquist rate in signal processing. This project investigates the feasibility of these new techniques for analysing 3-dimensional echoes sampled at a sub-Nyquist rate. It is an interdisciplinary effort that joins HZS marine engineers, experienced in echo sounding, with researchers, specialised in computational mathematics, from UAntwerpen. The ambition is to achieve better performance in the use of electromagnetic pulses to detect objects at a low cost by using the most current algorithms, bypassing the investment in switching to more expensive hardware.
Date:1 Jan 2019 →  31 Dec 2020
Disciplines:Computer science, Antennas and propagation
Project type:Collaboration project