DESIGN, ANALYSIS AND CHARACTERIZATION OF MILLIMETER WAVE/SUBMILLIMETER WAVE WAVEGUIDE FILTER

Abstract

Rectangular waveguides are used in the majority of millimeter and sub-millimeter wavelength radio receivers, transmitters, and components. Traditional machining techniques for waveguides operating above a few hundred GHz, on the other hand, are complicated and expensive. Using a segmentation technique, this thesis presents a method for designing effective bandpass waveguide microwave filters. The segmentation methodology was created with in-line filters in mind, and the combination of this technique with the coupling matrix formalism is the key contribution of this work. Because of their inherent broad Q, dielectric resonators have been commonly used in wireless and satellite communication systems to create low loss and narrow bandwidth filters. These resonators have recently been used in applications requiring low volume and mass for stringent requirements. Currently, the technology consists of a variety of dielectric resonator-based bandpass filters. To meet future targets, dielectric resonators must be used to decrease the expense of these filters in terms of both weight and volume. This technique has also been applied to the creation of a new construction for filters based on a wide band dielectric substrate (DS). A rectangular waveguide with irises, diced dielectric substrates, and two plates of aluminum for keeping the dielectric substrates make up the filter. The coupling irises on the covers are used to monitor the inter-resonator couplings. The filter has a small footprint and a thin profile, making it suitable for antenna integration. The filter structure lends itself to achieving high inter resonator coupling values. A twelve-order Chebyshev filter at 𝑓0 = 425 𝐺𝐻𝑧 with a fractional BW of 32.94 %, and A six-order Chebyshev filter at 𝑓0 = 77 𝐺𝐻𝑧 with FBW of 38.96 %, have been created. A novel design for simple fabrication was designed at W-band, and the EM simulation results indicate that the bandwidth of the filter is 28.4 GHZ at 𝑓0 = 99 𝐺𝐻𝑍 with an insertion loss of 0.3 dB, 12 dB return loss, and the Fractional Bandwidth: FBW = Δ= 0.2868 = 28.68 %.