A novel broadband microstrip patch antenna based on the spiral composite right/left-handed transmission line

A novel metamaterial-based spiral transmission line structure is presents and demonstrated as a single-layer single-patch microstrip patch antenna excited by microstrip line feed with broadband up to 8% and weak direction. This structure is in essence a spiral composite right/left hand (CRLH) transmission line (TL) incorporating circle microstrip patch for the multi-staggered resonance frequencies of patch antenna controlled operation, by which the broadband of the microstrip patch antenna is achieved.