Research On The Reconfigurable Antennas With MEMS Switch

In recent years, an innovative electronic reconfigurable antenna (ERA) technology has been put forward. The optimized electronic reconfigurable antenna is a new and promising area of antenna design that alters the key antenna element properties (radiation pattern, polarization, radar cross section, tuning, and input impedance) in a non-mechanical but controlled manner. It is very important and significant that a multi-band and multi-mode electronic reconfigurable antenna can substitute several antennas, which have been used on some platforms, especially space based platforms, because the substitution can reduce the size, weight, and cost of the platform. A multi-band electronic reconfigurable antenna can be reconfigured to operate over a relative bandwidth 100:1 or even 1000:1, but the normal antenna can't achieve so ultra-wide band and multi-band capability. So the electronic reconfigurable antenna is a soft radio system's candidate. America has paid great attention on the research on the ERA technology. "The study of micro-strip reconfigurable antennas" was released by Xiao Shaoqiu and Wang Bingzhong in the "2001 national microwave or millimeter-wave conference". Sith the reconfigurable antennas technology became one of the focus of antennas studies.Firstly, the paper analyzes the states in quo of the research on electronic reconfigurable antenna and then details the design of two kinds of antennas, the polarization diversity ERA antenna and the multi-band ERA antenna, using electronic reconfigurable antenna technology.Secondly, the RF switches is introduced with any important characters .Then several kinds of RF switches are compared.Then, I give out a design of a polarization diversity antenna. The antenna is a circularly polarized circular patch micro-strip antenna with single probe feed. On the side of the circular patch, there are two stubs with switches. The polarization diversity antenna can work in left hand circular polarization (LHCP) or in right hand circular polarization (RHCP) mode by changing the switches' states.In the last part of the papar, the multi-band reconfigurable antennas, frequency-reconfigurable rectangular slot ring antennas and patch antennas with switchable slots, are studied.