Radiation-rejection band inserted dual-band antenna using a split ring resonator for beyond 4G applications

ABSTRACT We propose a very simple but effective method to switch a single‐band antenna into a dual‐band antenna by inserting a narrow radiation‐prohibited band in the middle of the single pass band. To insert the radiation‐rejection band, we intentionally induce strong resonance on a metamaterial‐motivated split ring resonator (SRR) by placing it near a signal feeding transmission line of a proximity‐coupled microstrip patch antenna, which blocks out flow of electromagnetic waves through the line. To maximize the blockage, we cut the SRR into a quadrangular loop that is exactly interlocked with the two sides of the right‐angled microstrip line. Consequently, we show that we can split one pass band into two separated pass bands with an inserted sharp stop band in‐between. Good agreements between the prediction and the measurement prove the validness of our approach. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:961–965, 2014