SU1385166A1 - Bandpass filter - Google Patents

Abstract

This invention relates to a microwave technique. The purpose of the invention is to increase the selectivity. The filter contains a segment of 1. rectangular waveguide, in which inductive diaphragms 2 are placed, forming a circuit of waveguide resonators (BP.) 3. A diel is introduced. cylindrical resonators (DCR) 4, each of which is located in the center of BP 3. The resonant frequencies of DCR 4, located in adjacent BP.3, lie between the cutoff frequency and the frequency of the obstacle, respectively, above and below the average frequency of the passband. The planes of each DCR 4 are parallel to the narrow walls of segment 1. The adjustment of the resonant frequencies of BP 3 is carried out with screws. The high load quality of the DSB 4 provides a relatively narrow burst of attenuation at the pole frequencies of the barrier with a large steepness of the fronts, which increases the filter selectivity. 2 Il. C (L

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The invention relates to a microwave technique and can be used in frequency selective circuits of high power paths.

The purpose of the invention is to increase the selectivity of the filter.

Figure 1 shows a schematic bandwidth. filter; Fig.2 - the same in the projection section.

The band-pass filter contains a segment 1 of a rectangular waveguide in which inductive diaphragms 2 are placed, forming a circuit of waveguide resonators 3. Each of the dielectric cylindrical resonators 4 is located in the center of the waveguide resonator 3. The planes of each dielectric cylindrical resonator are parallel to the narrow walls of the segment 1 pr. waveguide.

One of the dielectric cylindrical resonators 4 is tuned to the frequency lying between the cutoff frequency and the barrier frequency below the passband, and the adjacent dielectric cylindrical resonator is tuned to the frequency lying between the cutoff frequency and the frequency of the obstacle above the passband.

The tuning of the resonant frequencies of the volga and water resonators 3 is carried out by screws 5.

Band-pass filter works as follows.

The microwave signal in the passband passes in section 1 of a rectangular waveguide through a circuit of waveguide resonators 3 with low losses. However, the presence of the dielectric cylindrical resonators 4 is not felt, since they are upset in the passband. At the fronts of the amplitude-frequency characteristic, due to the presence of dielectric cylindrical resonators 4, their corresponding tuning and location in the center of the waveguide resonators 3, attenuation bands appear. In this case, cylindrical dielectric resonators. 4 is excited directly by the electromagnetic field of the waveguide resonators 3 on the wave type Hj. The high loaded Q-factor of the dielectric cylindrical resonators 4 provides a relatively narrow burst of attenuation at the pole frequencies of the barrier with a large steepness of the fronts, which increases the selectivity of the band-pass filter.

Claims (1)

Invention Formula A band-pass filter containing a segment of a rectangular waveguide, in which inductive diaphragms are placed, forms a chain of waveguide resonators, which, in order to increase dielectric cylindrical resonators are introduced into it, each of which is located in the center of the corresponding waveguide resonator and its planes are parallel to the narrow wall of a segment of a rectangular waveguide, and the resonant frequencies of the dielectric cylindrical resonators placed in adjacent waveguide resonators lie between the cut-off frequency and the barrier frequency are respectively higher and lower than the average frequency of the passband. FIG 2