RU1807535C - Rejection filter - Google Patents

Abstract

Usage: microwave technology. in particular election chains x. SUMMARY OF THE INVENTION: The notch filter comprises a metal base on which a dielectric rod is placed, along the axis of which at least one conductor is installed on the side opposite to the side facing the metal base. An insulating dielectric with a dielectric constant less than the dielectric constant of the dielectric rod is introduced between the metal base and the dielectric rod. An expression is made to select the length of the conductor. 3 ill.

Description

The invention relates to radio engineering and can be used in high frequency blocks of a transceiver path.

The aim of the invention is to increase the level of rejection. ,

In FIG. 1-3, the proposed notch filter is provided, consisting of a grounded base 2, an insulating dielectric 2, a dielectric 3 rod, an input and output line 4. 5 additional conductors 6.

The device when applying to its input a microwave signal operates as follows.

Upon the arrival of additional conductors and in the presence of a microwave signal (in the general case of a complex spectrum), the input line 4 will channel the microwave power to the output line 5 through an insulated dielectric waveguide formed by elements 1-3 without significant losses. The introduction of additional conductors with certain geometric dimensions leads to the selection of energy in a certain frequency band for. due to the appearance of resonance in the microstrip type resonators formed by elements 1-3 and 6. Ultimately, the frequency bands are cut out in the complex spectrum of the signal fed to input 5; The frequencies of the notch band are determined by the geometric dimensions of the conductors, the dielectric rod, the insulating dielectric, as well as the dielectric permittivity of the materials from which the rod and the insulators are made dielectric. Moreover, the width of the metallized sections will significantly affect the quality factor of the resonators, and their length will determine the resonant frequency. For

with

ABOUT

h | SL CO SL

forming the desired frequency response. At a given frequency band, the number of resonators can vary.

The filter provides a notch of -30 dB frequency band 5.2% f0 at f0,, 45 GHz. The maximum level of cut-off is -47 dB, losses in the transparency band do not exceed 4 dB.

Compared with the selected prototypes, the proposed technical solution provides a significantly higher total level of notch. as well as a notch band and a lower level of loss in the transparency band. In the microstrip design for the millimeter wave range, only notch filters with an Af of about 1% are known. In the waveguide design, the notch band is already narrower and amounts to about 0.5%.

FORMULA AND SECTION

A notch filter containing a dielectric rod and a metal base, while on a dielectric rod on the side / opposite to

5

0

At least one longitudinal conductor is placed in the roma facing the metal base, characterized in that, in order to increase the notch level, an insulating dielectric with a dielectric constant lower than the dielectric constant of the dielectric rod placed on the metal base is inserted, the dielectric rod is installed on an insulating dielectric, and the length li of the conductor is selected from the condition

li p A9 / 2 + 0.4 (W - h) /,

where Hell is the T-wavelength of the transmission line formed by a dielectric rod, an insulating dielectric and a metal base;

W is the width of the conductor;

h is the thickness of the dielectric rod, Јeff is the effective relative permittivity.

./

AT

FIG. 2