Investigation of loaded microstrip patch antennas for wide-band MRI-wave applications

Results of an investigation into the enhancement of microstrip patch antenna bandwidth are presented. A resistive load is strategically coupled to the patch antenna in a two port configuration. Variation of coupling to the resonant patch yields bandwidths ranging from a few per cent to well over 60 per cent (VSWR less than or equal to 2). This technique is then applied to a serial array of patch antennas. The series array is shown to improve the efficiency of the loaded patch antenna; Computed and measured results at X-band are in close agreement. Application is envisaged for wide-band mm-wave communications and radar.