Research On 433M Miniaturized Micro-strip Antenna

There has been a growing demand for making the wireless systems smaller and improving the overall performance of the system. This brings up the need to have more compact miniaturized antenna models, with better performance. Micro-strip antenna has been widely used during the recent decade because its outstanding properties of low profile ,low cost ,light weight, easily fabricated and easily integrated with radio frequency and microwave circuit.This paper has an overview on the researching progress and the analytical methods of micro-strip antenna. Several methods for the miniaturization technology of micro-strip antenna have been discussed. Meanwhile, two miniaturized 433MHz micro-strip antenna have been proposed.In our antenna design the biggest limitation and challenge was to accommodate an antenna with a relatively long wavelength of 433MHz in mini-card size area, and achieve a better gain.In the design of the serrated pattern micro-strip antenna, to accommodate in a small card, we used a meander line style structure of the antenna and then shorted the antenna's radiating part with the ground plane . The antenna is low cost as it is matched to 433MHz without using a matching circuit or any extra passive lumped component to boast the capacitance of the antenna. The achieved gain of the antenna is also better than the previously used loop antenna.In the design of the double-ground structure antenna, we used a double-ground structure and also shorted the antenna's radiating part with the ground plane, to further decrease the size of the antenna structure. Then we used lumped components to make the antenna match to 433MHz.The two antenna are both made for small wireless device, such as wireless receivers and for small card size indoor readers.