1. INTRODUCTION
With the rapid development of wireless communication systems, there is an increasing requirement
for printed wideband antennas with small size [1, 2]. Among the possible candidates reported in the
literature, owing to their many salient features such as light weight, low cost, ease of fabrication, and
suitability for integration with microwave integrated circuits [3], printed dipole antennas are considered
to be highly prospective and have been widely investigated [4{6].