Modern military ships are nowadays heavily equipped with antennas and radars dedicated to communication and combat systems. As a result, the arrangement and positioning of antennas and radars are difficult from an Electromagnetic Waves (EW) propagation point of view.
Problems of shadow zones, path loss of antennas, mismatch of antennas with their generator, strong values of radar signature and so on, can appear; all these are in fact Electromagnetic Compatibility (EMC) problems. The radomes of ships are the base of all these phenomena.
The experience of Prinvinvest, and actual needs suggest that the study of EMC problems inside radomes of military vessels and broadband devices for defense applications in general, are urgent.
In order to reduce EMC problems, Prinvinvest has developed thin and non-bulky broadband electromagnetic radar absorbers based on the metamaterials concept.
Results
One radar absorber published in Nature Scientific Reports journal which is 5.2 mm thin achieves more than 90% of absorption of EW in the whole range of 4.8 – 11.1 GHz (see Figure (a)) for co-polarized TE and TM waves.
Another 3.2 mm thick radar absorber achieving at least 90% of absorption of EW in the whole band of 5.6 – 9.1 GHz for co-polarized TE and TM waves has been published in mdpi Materials journal (see Figure (b)).
A final work on the systematic design of flexible broadband radar absorbers have been published in Progress in Electromagnetic Reports journal.
The presented radar absorber is 8 mm thick and achieves more than 90% of absorption in the whole range of 3 – 7.8 GHz and is efficient for both co and cross polarizations.
Further works by Privinvest are ongoing on cylindrical and conformal radar absorbers.