الفهرس 
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Abstract
The objective of this thesis is to design and analyze RF reconfigurable compact filters using modern techniques such as meta-materials and electromagnetic band gap structure to meet the most of the requirements of wireless communication applications as in ultra wide band wireless applications, wireless fidelity (Wi-Fi) applications, Worldwide Interoperability for Microwave Access (Wi-Max) applications, WLAN applications, wireless laptops and mobile applications.
The reconfigurable compact filters were designed and analyzed using software packages including CST Microwave Studio, HFSS, ADS and Matlab-2016. The mini circuit switching matrix was used instead of RF PIN diodes in the switching process.
These filters were made using thin film technology and photolithographic technique on Rogers RO3006 (lossy) substrate with (ε r = 6.15, h = 1.52 mm), and Rogers RT/Duroid 5880 with (εr =2.2, h =0 .787mm). The measured results are characterized using a N9928A FieldFox Handheld Microwave Vector Network Analyzer, 26.5GHz. The design was validated by comparing simulation results with the laboratory measurements.
Three types of filters are designed, analyzed, fabricated and measured. First, the design and implementation of microstrip filter to satisfy the Federal Communications Commission ultra-wideband (FCC-UWB) specifications and also creates and controls sharp rejection notch-bands within the filter’s passband in order to provide interference immunity from unwanted radio signals, such as wireless local area networks (WLAN) and worldwide interoperability for microwave access (WIMAX) that cohabit within the UWB spectrum. This filter is based on CRLH concept consisting of an asymmetric transmission line unit cell with a short-circuited inductive stub to realize high performance in an operation band from 3.1 to 10.6 GHz with a very compact size of 16.4 mm × 5.0 mm. The main advantage of the proposed filter is that four notch frequencies are tuned in the UWB frequency band. The notch frequencies of the filter can be changed by increasing the length of the coupling stub which is controlled by using switching matrix equipment (Mini Circuit) instead of PIN diodes. To validate the design theory, a microstrip UWB BPF with four notch bands centered at frequencies 6.18, 5.9, 5.7, and 5.5 GHz is designed and fabricated. Good agreement is found between simulated and measured results.
Second, the design and implementation of two microstrip filters satisfying the Federal Communications Commission Ultra-wideband (FCC-UWB) specifications and also control the center frequency and bandwidth of the filters passband are presented. These filters consist of two distinguishing parts, Electromagnetic bandgap (EBG)-embedded multiple-mode resonator (MMR) and interdigital coupled lines to realize high performance in the operation band with a compact size of 14.0 mm × 10.1 mm. The main advantage of the two proposed filters is that three different bands are tuned. The 1st tuned band is from 3.5 GHz to 11.4 GHz for the first filter and from 3.1 GHz to 11.6 GHz for the second proposed filter, respectively. The 2nd tuned band is from 3.5 GHz to 7.5 GHz for the first filter and from 3.1 GHz to 7.8 GHz for the second proposed filter, respectively. While the 3rd tuned band of the first proposed filter is from 3.5 GHz to 5.9 GHz and from 3.1 GHz to 5.8 GHz for the second proposed filter. The bandwidth of the filters can be changed by increasing the length of the outer open circuited stubs which are controlled by using switching matrix equipment (mini circuit, replacement of PIN diodes). To validate the design theory, a reconfigurable UWB bandpass filters (BPFs) with EBG Embedded MMR are designed, fabricated and measured. Good agreement is found between simulated and measured results.
Third, the design and implementation of a reconfigurable ultra wide band BPF using rectangular shape DGS to satisfy good passband selectivity by the transmission zeros and good passband under -15dB from 3.6 GHz to 10.6 GHz is carried out. The stopband characteristics of this filter are less than -20dB up to 17GHz. The filter has compact size of 12.5 mm × 10 mm. The main advantage of the proposed filter is that reconfiguration from UWB to dual band from 3.6 GHz to 5 GHz and another from 9 GHz to 10.8 GHz is obtained. Therefore, it is expected that the proposed structure with its characteristics will be a strong candidate to avoid the interferences from the narrow band services such as the WLAN, WIMAX, C- band of radar from 5.85 GHz to 8.20 GHz, and interference with X (Military) band of satellite from 7GHz to 8 GHz. It is suitable for modern RF and microwave satellite and mobile communication systems. To validate the design theory, electronically switchable ultra-wide band / dual band bandpass filter is fabricated and measured. Good agreement is found between simulated and measured results.