Patch antenna with switchable slot (PASS): Dual-frequency operation

A novel kind of microstrip antenna, a patch antenna with a switchable slot (PASS), is proposed in this paper. A slot is incorporated into the patch, and a p-i-n diode is utilized to switch the slot on or off. This antenna can work at dual frequencies with a small and flexible frequency ratio and the same polarization. Experimental results validate this concept. (C) 2001 John Wiley & Sons, Inc.