SINGLE - FEED DUAL- FREQUENCY DUAL- POLARIZED SLOTTED SQUARE MICROSTRIP ANTENNA G. S. Binoy ,' C. K. Aanandan ,' P. Mohanan ,' K. Vasudevan,' and K. G. Nair' 'Department of Electronics Cochin University of Science & Technology Cochin-22, Kerala, India Received 5 January 2000 ABSTRACT: A novel dual frequency dual-polarized square microstrip patch antenna embedded with a slot is presented. The proposed antenna offers tunability of the frequency ratio between the two frequencies by adjusting the slot dimensions. This configuration also provides a size reduction up to -51 and 35% for the two modes as compared to a square microstrip patch antenna . ® 2000 John Wiley & Sons, Inc. Microwave Opt Technol Lett 25: 395-397, 2000. Key words: microstrip antennas; dual frequency; dual polarization; slot INTRODUCTION Dual-frequency operating microstrip antennas find wide ap- plications in GPS, regional mobile satellite arrays, large feed arrays for offset reflectors, and other common transmit and receive antennas [1, 21. A compact dual-band dual-polariza- tion microstrip patch antenna capable of generating- two distinct frequencies with different polarizations recently has MICROWAVE AND OPT