A novel EBG structure with spiral line bridges for radiation suppression in marine VHF band

Abstract

The very high frequency (VHF) marine communication band (156–165 MHZ) is consequential for ship navigation safety, having the radiation limitation of 24dB·μV/m in this band and 54dB·μV/m in the adjacent band. The existing technologies are not enough to achieve targeted suppression of the radiation disturbance in this frequency band at PCB-level, which is equivalent to imposing strict limits on the whole test frequency band, making it necessary to pay an extra cost to achieve electromagnetic compatibility of marine electronic equipment. A spiral line bridged electromagnetic band gap (SL-EBG) is proposed for the radiation suppression of the marine VHF band. Based on the calculation of parasitic parameter, the equivalent circuit of SL-EBG is modeled; simulation and measurement are also performed to analyze the characteristic of SL-EBG. The stopband of the proposed EBG structure is 100MHz–300MHz, which S21 parameter is −27dB for two units, −59dB for four units and −72dB for five units at 160MHz.