Showing papers on "Waveguide filter published in 1978"
19 Jul 1978
TL;DR: In this article, the design of odd order elliptic function bandpass filters using a minimum number of cavities connected by simple and resonant coupling elements is described, and experimental results of a 3-pole, 20-MHz bandpass waveguide cavity filter centered at 3890 MHz correlate well with theory.
Abstract: Multiple coupled high Q cavities can be used to generate even order elliptic function bandpass filter responses. This paper describes the design of odd order elliptic function bandpass filters using a minimum number of cavities connected by simple and resonant coupling elements. Experimental results of a 3-pole, 20-MHz bandpass waveguide cavity filter centered at 3890 MHz correlate well with theory.
17 citations
TL;DR: Parallel coupled microstrip lines in an inhomogeneons medium are studied in this article, where the quasi-static capacitance is shown to be linear with regard to the dielectric constant epsilon/sub r/ simplifying the formalism used for analyzing microstrip filters.
Abstract: Parallel coupled microstrip lines in an inhomogeneons medium are studied. The quasi-static capacitance is shown to be linear with regard to the dielectric constant epsilon/sub r/ simplifying the formalism used for analyzing microstrip filters. The electromagnetic advantages of the homogeneous medium carry over to the inhomogeneous medium. This result is obtained by equalizing all the velocities of the propagation modes.
13 citations
27 Jun 1978
TL;DR: Using low dielectric constant substrates (Duroid, epsilon = 2.22), various millimeter wave filters, diplexers, and triplexers have been fabricated, originally constructed on open microstrip, circuits exhibited considerably lower losses when enclosed in channels and integrated with printed circuit to waveguide transitions.
Abstract: Using low dielectric constant substrates (Duroid, epsilon = 2.22), various millimeter wave filters, diplexers, and triplexers have been fabricated, Originally constructed on open microstrip, circuits exhibited considerably lower losses when enclosed in channels and integrated with printed circuit to waveguide transitions.
9 citations
TL;DR: In this article, the frequency-dependent properties of symmetrical microstrip Y-junctions and 120° bends were investigated using a waveguide model with frequency dependent parameters, and a field-matching technique proposed by Kuhn was employed to compute the scattering matrix of a Y-junction with three equal line impedances.
Abstract: A method is described for calculating the frequency-dependent properties of symmetrical microstrip Y-junctions and 120° bends. The Y-junction includes angles of 120° and may have two different line impedances. Using a waveguide model with frequency dependent parameters, a field-matching technique proposed by Kuhn is employed to compute the scattering matrix of a Y-junction with three equal line impedances. The generalised telegraphist's equations are used to extend the calculations to Y-junctions with two different line impedances. The transmission properties of 120° bends are derived from the Y-junction by a symmetry consideration. The theoretical results are compared with measurements, and theory and experiment are found to correspond closely.
7 citations
Patent•
20 Jul 1978TL;DR: In this paper, the authors proposed a method to construct high frequency s.a.w. type filters by reference to already available inductor and capacitor values from tables of low pass filter designs.
Abstract: Surface acoustic wave resonators are used to provide band pass filters. The length of each resonator is related to the lumped constant inductor and capacitor values of the components of the low pass filter equivalent. This invention allows high frequency s.a.w. type filters to be constructed by reference to already available inductor and capacitor values from tables of low pass filter designs.
6 citations
TL;DR: A simplified method of the design of a parallel coupled microstrip band-pass filter is outlined in this article, and a set of curves are presented for getting the geometry for filters with band widths less than 10%.
Abstract: A simplified method of the design of a parallel coupled microstrip band-pass filter is outlined A set of curves is presented for getting the geometry for filters with band widths less than 10% A filter is designed and tested for illustration
6 citations
4 citations
TL;DR: In this paper, a reactive fourth-harmonic filter operating at a fundamental power level of 400-kW was described, which was used in the NASA Deep Space Instrumentation Facilities. But the design approach including power handling capability considerations was not discussed.
Abstract: A reactive fourth-harmonic filter operating at a fundamental power level of 400-kW CW is described. The filter, used in the NASA Deep Space Instrumentation Facilities, operates in an S-band (WR-430) waveguide run and it effectively attenuates the fourth harmonic of the fundamental transmit frequency near 2.1 GHz by a minimum of 40 dB. The design approach including power handling capability considerations is presented. Also included are some details of mechanical construction, tuning procedures, and results achieved.
4 citations
Patent•
16 Oct 1978
TL;DR: The low insertion loss waveguide band pass filter comprises M waveguide resonant cavities provided with intercoupling plates, M being an integer as mentioned in this paper, each cavity has a physical length equal to "n" times the half guide wavelength, where n corresponds to the third index of a TE mode microwave to be transmitted, n is at least larger than one.
Abstract: The low insertion loss waveguide band pass filter comprises M waveguide resonant cavities provided with intercoupling plates, M being an integer. Each cavity has a physical length equal to 'n' times the half guide wavelength, where 'n' corresponds to the third more index of a TE mode microwave to be transmitted, n is at least larger than one. The filter may be a dual mode filter having cavities of the same cross-sectional area, each cavity having a length equal to n times the half guide wavelength at the centre frequency of the filter.
4 citations
27 Jun 1978
TL;DR: In this article, an improved waveguide bandstop filter configuration with two realizable design examples is presented with the same dielectric resonators used in the original waveguide filter configuration.
Abstract: Waveguide bandstop filter structures utilizing dielectric resonators proposed in the literature have problems in realization. An improved filter configuration is presented with two realizable design examples.
3 citations
Patent•
09 Feb 1978TL;DR: In this paper, a dielectrically loaded four-port waveguide circulator is used with a reflected-wave maser connected to a second port between first and third ports to form one of a plurality of cascaded maser waveguide structures.
Abstract: A dielectrically loaded four-port waveguide circulator is used with a reflected-wave maser connected to a second port between first and third ports to form one of a plurality of cascaded maser waveguide structures. The fourth port is connected to a waveguide loaded with microwave energy absorbing material. The third (output signal) port of one maser waveguide structure is connected by a waveguide loaded with dielectric material to the first (input) port of an adjacent maser waveguide structure, and the second port is connected to a reflected-wave maser by a matching transformer which passes the signal to be amplified into and out of the reflected-wavemaser and blocks pumping energy in the reflected-wave maser from entering the circulator. A number of cascaded maser waveguide structures may thus be housed in a relatively small volume of conductive material placed within a cryogenically cooled magnet assembly.
22 Mar 1978
TL;DR: In this paper, the authors describe compact band-pass filters for duplexer of 900 MHz high capacity mobile radio communication equipment, which are constructed with a newly developed resonator of which Q-factor is higher than conventional capacitor-loaded resonators especially in the range of the small size resonator.
Abstract: This paper describes compact band-pass filters for duplexer of 900 MHz high capacity mobile radio communication equipment. Band-pass filters developed here are constructed with a newly developed resonator of which Q-factor is higher than conventional capacitor-loaded resonators especially in the range of the small size resonator. Another type of filter with this resonator is fabricated using high dielectric material which was developed for the purpose of resonators at microwave frequency.
27 Jun 1978
TL;DR: In this article, the internal fields of two coupled radial waveguides are derived by an array of annular slots on the common boundary, and it is shown that higher order modes have significant effect on the solution, for a precise evaluation of the field their contribution must also be included.
Abstract: Using a boundary value treatment, a method is established which gives the internal fields of two coupled radial waveguides. The coupling is achieved by an array of annular slots on the common boundary. It is shown that, in general, higher order modes have significant effect on the solution, for a precise evaluation of the field their contribution must also be included. The possible application of the method for the design of microwave filters with band-pass characteristics is also discussed.
01 Oct 1978
TL;DR: In this paper, a new type of dielectric resonator filter was proposed, where cylindrical dielectrics were enclosed in evanescent metallic cavities, and the electromagnetic fields inside the metallic cavity have been derived assuming the dipolar TE01p resonator as a density of magnetic moment centered inside the cavity.
Abstract: This paper discusses a new type of dielectric resonator filter wherein the cylindrical dielectric resonators have been enclosed in evanescent cylindrical metallic cavities. The electromagnetic fields inside the metallic cavity have been derived assuming the dipolar TE01p dielectric resonator as a density of magnetic moment centered inside the metallic cavity. Coupling between two such cavities has been determined and a two cavity filter has been realised which shows good agreement with the theoretical results.