Planar filters for multi-band wireless communication

• Main Author: Lim, Ah Chai.
• Other Authors: Zhu Lei
• Format: Final Year Project
• Language: English
• Published: 2010
• Subjects: DRNTU::Engineering::Electrical and electronic engineering::Antennas, wave guides, microwaves, radar, radio
• Online Access: http://hdl.handle.net/10356/40474
• Institution: Nanyang Technological University

The main purpose of this project is to design and simulate microstrip multi-band Band Pass Filters (BPF) for its application to wireless communication namely Wireless Local Area Network (WLAN) and Wireless Metropolitan Area Network (WiMax). This thesis includes the study of using various types of microwave filter designing. Coupled-line filter, Stepped impedance Resonator and Short Circuit Stub Loaded as well as the hairpin-feeder are extensively researched into so as to achieve the optimized the filter response. To achieve the frequency and bandwidth requirements for the WLAN application, resonant frequencies of 2.4GHz and 5.425GHz are characterized, by using the ½ λ Stepped Impedance Resonator (SIR). Furthermore, use of parallel couple microstrip has further enhanced the frequency-distributed coupling performance, in terms of different coupling lengths. The degree of coupling at the two resonances, has been adjusted to achieve the dual-pass band performance and result. For the WiMax application, a Stub Short Circuit Loaded Resonator (SSLR) has been used to characterize the even-mode and odd-mode characteristics to fulfill the frequency and bandwidth requirements. The even-mode has also been conveniently tuned with minimum effect on the odd-mode frequency characteristics. Finally, a Hairpin-line feed structure is used to attain more coupling degree on the Tri-band filter. Besides the analysis of various microwave filter parameters, Electromagnetic (EM) Sonnet program has been used to simulate the design. A detailed explanation on the EM Sonnet has been included in this thesis.