Design and Analysis of Frequency Reconfigurable Band Pass Filter for Wireless Applications

Abstract

Filter devices are very useful component in many wireless communication applications because they are used to select or reject specific frequency ranges. In terms of system filtration, many system requires multifunctional functions for switching of particular frequency band according to the specified applications. The conventional method used is a filter bank, which takes up a lot of space on the circuit board. The reconfigurable or switchable microwave filter is a new technology for microwave communication. It can switch between different frequency band for multi-function operation through a single filter structure. The advantage is that it reduces the size of the filtering device. This research work presents a design method and analysis of a three band pass filter. The tri band pass filter has a resonance frequency of 2.4 GHz in WLAN, 3.2 GHz in Wi-MAX, and 5.2 GHz used in GSM applications as a function of reconfigurable bandpass filter. Microstrip filters are designed by using different techniques. The complementary split ring resonator (CSRR) is one of the technique used for band pass filter design. The CSRR structure yields a negative value of its effective permittivity at a narrow band near its resonant frequency. The CSRR structure improves the performance of the microstrip bandpass filter in terms of gain and bandwidth. The CSRR structure is also used in the design of integrated filters for multi-band operation. Initially, a parallel coupled and hairpin type dual-band filter is designed after that CSRR structure is used based on its advantages. The switching between bandwidth is achieved by using the PIN diode as a switching element. So by using reconfigurable filter design technology, the same filter can be tuned for various frequencies used in wireless communication. The design and simulations are performed using HFSS simulation software. newline