Edge-radiating slot antenna based on half-mode substrate integrated waveguide

Lots of substrate integrated waveguide (SIW) slot antennas appear to satisfy the extensive and intensive growth of wireless communication systems. However, there were few reports about edge-radiating slot antenna based on SIW technology. In this study, a half-mode SIW (HMSIW) edge-radiating slot antenna is proposed for the first time by etching transversal slots both on the upper and lower surfaces of HMSIW. The radiation field of this antenna has been deduced from the field distribution of HMSIW. A 6-slot-pair antenna worked at 3.0GHz with gain of 5.8dBi is obtained by regulating the size and the number of slots. Through setting matching posts and a terminal load, the bandwidth can be expanded from 2 to 9.7%. The measured results show that the matching-type antenna has radiation efficiency about 0.59, beam directions ranging from 0 degrees to 53 degrees and gains within 5.0-7.5dBi in 3.05-3.35GHz. This antenna has advantages of low profile, easy fabrication, wide bandwidth and frequency-scanning property, which are great for microwave radar applications.