Polarized Reconfigurable Patch Antenna

With the rapid development of electronic technology, electronic system presents the trend of broadband, large capacity and multi-function, which lead to the rapid increase of the number of antennas in the electronic system. It is a big challenge to improve the electromagnetic compatibility of electronic systems, reduce weight and cost and restrict the rapid development of wireless communication and its applications. As a new type of antenna, reconfigurable antenna is famous for solving the bottleneck problem of wireless communications.At first, the present situation of all kinds of reconfigurable antennas as well as the way of realization is introduced in this paper. Then the main parameters of the antenna and the basic theory of microstrip antenna are introduced briefly. At last, by studying the multi-frequency band and miniaturization of antennas, a PIN switch control circular polarization reconfigurable miniaturized antenna is proposed. By using the diodes to adjust the state of the stubs, this antenna can be either right hand circular polarization (RHCP) or left hand circular polarization (LHCP). A shorting pin is used to improve the antenna’s impedance matching and a triangle slot is used to minimize the size of the antenna. Good circular polarization antenna characters are proved through simulation. Finally, a new kind of frequency and polarization hybrid reconfigurable antenna is designed based on analyzing of single-feed circular polarized microstrip antenna and changing the surface current distribution of an antenna using the method of loading switches. By changing the state of the loading PIN switches, the states of right hand circular polarization (RHCP)、left hand circular polarization (LHCP) and linear polarization in different frequencies can be achieved.