| Coupled meander lines and thermal driven lateral MEMS switch were designed, based on the analysis of composite left/right handed transmission line (CRLH TL) structure and Micro-Electro-Mechanical Systems (MEMS) technology. The band pass filter, band reject filter, micro strip balun, reconfigurable filter using PIN diode and reconfigurable filter based on the MEMS switch were designed by the coupled meander lines and MEMS technology. And also, a micro directional antenna which has the CRLH TL property was fabricated by MEMS technology.(1) The characteristic of coupled meander lines and interdigital capacitor structure were analyzed. Band pass filter, microstrip balun, band rejected filter and also electro reconfigurable filter were designed based on the coupled meander lines structure. The band pass filter was fabricated by MEMS technology, which has left handed characteristic at special frequency, so it has a wide pass band. And also the size of the filter is small. The length of the main structure is about 1/50 of the working wavelength. To avoid the complexity of the metal via, a multi periods coupled meander lines micro balun without connecting ground was designed. It has a virtual ground at the axis of symmetry which was shown in simulation results, so a real ground is not needed. It was also be shown in the simulation results that the electromagnetic field transmits backward in special frequency. Besides these devices, a dual structure of the coupled meander lines was designed and was used in a band rejected filter. The sample was measured after fabricated by MEMS technology. The measurement and simulation results showed that the filter shows left handed characteristic at high frequency which is different with normal coupled meander lines. On the other hand, the left handed region is wide this is the same with normal coupled meander lines. A novel structure developed from coupled meander lines and its dual structure was studied, and was used as the main structure of a reconfigurable filter. The reconfigurable filter using diode as the switch can work as band pass filter and also band reject filter when the diode state is switched. After fabricating by MEMS technology the sample was measured. The measurement result is similar with the simulation results.(2) A novel lateral thermal drive MEMS switch was designed, and was used in the reconfigurable filter. The switch is composed by a"U"shape beam and a cantilever beam. The cantilever beam is driven by the"U"shape beam which is placed vertically to the previous one. The Switch is based on the magnification of the thermal deformation of the"U"shape beam. The fabrication process was designed according the structure of the switch, especially the etching solution for removing the sacrifice layer. To design a switch that the DC circuit is isolated with RF circuits, SU8 was selected as the connecting part of the two circuits. The measurement results showed that the power consumption of the switch is about 170 mW and the switching time is about 12 ms. After the switch was fabricated, it was used in the reconfigurable filter. The simulation and measurement results showed that the reconfigurable filter can reduce the power leakage.(3) A micro metamaterial directional antenna was fabricated by MEMS technology. A high resistance substrate based on CRLH TL theory was used as the substrate of the antenna. This can reduce the thickness of the antenna. After fabricated by MEMS technology, the sample was measured; the measurement and simulation results showed that the antenna has a good directional emitting characteristic.Coupled meander lines CRLH TL structure and the fabrication methods by MEMS technology were proposed in this paper. Several microwave devices were designed and fabricated. A thermal drived MEMS switch was also designed and was used in the reconfigurable filter. These designs reduced the device size and make the device more suitable for the portable wireless electro system.
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