DE1801895B2 - GROUND EQUIPMENT - Google Patents

Description

The invention relates to a Bode equalizer consisting of a bridged T-element, in whose bridging and shunt branch in each case at least one correct wave resistance provided with a variable terminating resistor Auxiliary quadrupole is arranged.

It is often used to equalize the frequency-dependent attenuation curve of transmission systems required that several equalizers connected in a chain with different frequency dependencies their damping functions can each be adjusted proportionally. Such equalizers are usually implemented as a Bode equalizer. A disadvantage of this method is that each individual Equalizer causes a basic attenuation that is at least as large as the maximum attenuation stroke its equalizer curve. Bode equalizers are e.g. B. from German Patent 881,528 known.

A Bode equalizer is formed by a bridged T-circuit; as a bridging resistor and the input resistances of terminated with real resistances serve as cross resistance Auxiliary quadrupoles. The transmission behavior of the auxiliary quadrupoles determines the frequency response of the equalizer damping, while the hub is set by the terminating resistors. Thereby are in general the auxiliary poles lying in the shunt branch and in the bridging branch of the T-circuit to each other dual.

Such an equalizer is, for example, from German Auslegeschrifl 1 255 143. in particular F i g. I c. known. With this equalizer, however, a fan-out that is proportional to the square root of the frequency is intended Attenuation path are obtained to compensate for the cable attenuation caused by the skin effect permitted, since this cable attenuation over the frequency is also based on a square root function runs. The setting of several different, independent frequency responses is, however not possible with this arrangement.

It is the object of the present invention. to create a Bodc equalizer arrangement which allows two or more frequency responses by adding two or more freely adjustable, from each other to generate separate and proportional partial strokes.

The Bode equalizer is designed according to the invention in such a way that the bridging impedance of the series branch is divided into several parallel-connected two-pole, each from the series circuit a fixed resistor and the input resistance of an auxiliary quadrupole, which can be changed with a Resistance is complete, and that the shunt arm impedance is dual to the bridging impedance is.

The auxiliary four-poles can be designed as bridged T-members, in which the bridging resistance and the shunt arm resistance are dual to one another

The bridged T-links of the auxiliary quadrupoles can also use all-pass links in the form of cross links or equivalent structures.

These measures result in an equalizer that is always matched on both sides and in which the basic attenuation in comparison with known arrangements is considerably reduced when the basic attenuation is certain Falls below values without additional work on coils and capacitors. The Bode equalizer can in particular be designed so that the standardized fixed resistances are the same i-times the product of the basic attenuation factor reduced by one times that reduced by one (;? - i) -fold basic damping factor, divided by the basic damping factor reduced by one (2 // - l) -fold and that the normalized short-circuit resistances of the auxiliary quadrupoles in the bridging branch are equal to the basic attenuation factor times the basic attenuation factor reduced by one. divided by the reduced by one (2 / i - 11 times Basic damping factor.

By designing the arrangement in this way, the greatest possible stroke proportionality and The best possible symmetry of the corresponding positive and negative strokes is achieved.

Another solution to the above problem is that in a Bode equalizer from a bridged T-link, in which the bridging impedance from the parallel connection of a fixed resistor and the input resistor of a auxiliary quadrupole with variable terminating resistance and the shunt arm impedance from the series connection of another fixed resistor and the input resistor Another four-point auxiliary with a variable terminating resistor, correct for the corrugation resistance exist, is designed in such a way. that the two auxiliary poles have different transmission levels, that the normalized fixed resistance of the bridging impedance is equal to the product of the basic attenuation factor reduced by one and the basic attenuation factor increased by three. divided by three minus the basic damping factor. that the normalized fixed resistance in the Querzvvcig resistance reciprocal !. to the normalized fixed resistance in the bridging branch. that the normalized wave resistance of the auxiliary quadrupole in the bridging branch is equal to the product of the reduced by one Basic damping factor and the basic damping factor increased by three. divided by double Basic damping factor, and that the normalized wave resistance of the auxiliary quadrupole in the shunt branch is reciprocal to the normalized wave resistance of the auxiliary quadrupole in the bridging branch.

IO

Using the exemplary embodiments according to FIGS. I to 3 the invention is explained in more detail.

F i g. 1 shows a Bode equalizer according to the invention with double attenuation expansion (ji = 2) and mutual adaptation. The equalizer consists of a bridged T-element, in which the bridging resistance is divided into two parallel-connected two-poles, each of which consists of a series connection of a fixed resistor R and the input resistance of an auxiliary quadrupole VP \ or KPIII.

In the special embodiment, the auxiliary quadrupoles themselves are made up of bridged T-links, the series branch resistances of which are denoted by H ^ ₁ or W _{u . They are terminated with variable resistances W _x and W _1. The transverse branch of the bridge T-link consists of two poles lying in a row, each of which in turn consists of one

Fixed resistor-g "and a parallel to it

K

Auxiliary quadrupole KPII or KPIV exists, which is dual dimensioned to the respective auxiliary quadrupole of the series branch is and series branch resistances

respectively.

^r o \

^ 02

as well as a variable terminating resistor

respectively.

W ₁

having.

The resistances R are measured as shown below:

40 where q ₍ , equals c "", where ο _{υ means} the basic damping. Η _υ is the basic damping factor. The series branch resistances of the auxiliary four-pole poles W _{t) t} , W _Oi have the following value:

45 4 <7o (<? ,,, - 3 * 0-1

The series arm resistances in the auxiliary quadrupoles of the shunt arm are then correspondingly dual, namely

Hi ₁ .

respectively.

dimensioned.

The following equation then results for the transfer factor:

+ H ₀ ■ It ₁ ■ c- ^2ft + Η _υ ■ O ₂

. _{f) l} .

"-H ₀ U ₁ -C- ² " -% ± iU, * ₂ -e-

<? o - '
(2 / i-IJio-

and "v -

"+ W _n .

It was assumed that the kidney was over- kidney. The transmission factor results from the load factor as precisely as possible using the chain formula below:
circuit of two Bode equalizers, where
the transfer rate for this is given as follows ι, _H , - 2 "

can be. 5 e = i / _n · -—

I - H ₀ Ae " ² "

_p «. "(1 + W ₀₁ O ₁ C ² N (I + H ₀₁ O ₁ e" ² ") ^with .

^{2 2} "

(I - H ₀₁ #, e ² * ') (1 - H ₀₂
For the damping stroke results

H -

and

(in - \) q ₀ - I

w;

_ a _h O ₀ -

'' Ι fι (/)]
- - ₂ ; ₊ T

2μ + 1

if π-I auxiliary quadrupoles are terminated with the characteristic impedance.

F i g. 3 shows a circuit with which the aforementioned object can also be achieved. 15) The bridging resistor consists of

a fixed resistor R ₁ and an auxiliary quadrupole KPI lying parallel to it, while the shunt arm resistance from the series connection of the fixed resistor

wobeia ^ the operational _{damping.a 0} the basic damping position R ₁ and the auxiliary quadrupole KPII is built up. means. The dimensioning of the standardized fixed resistances and

F i g. 2 shows a basic circuit diagram for n-like components of the series-branch resistors of the auxiliary distortion unit, where the resistances R are to be dimensioned as follows from four poles and the transfer factor: from the following formulas:

The series branch resistances of the auxiliary quadrupoles in the bridging branch then result as follows:

d _

Jfc -Ji (q ₀ + \ ₃ _-__.

A ~ _5 °

The series branch resistances of the auxiliary quadrupoles in the shunt branch are again to be correspondingly dual-dimensioned.

y _

(q ₀ - I) * (<j ₀ + 3f

- H ₀ O ₁ e

(1 + H ₀

4H ₀ .?,

1 sheet of drawings

Claims (5)

Patent claims: 1. Bode equalizer consisting of a bridged T-element, in whose bridging and shunt arm in each case at least one auxiliary quadrupole with a variable termination S resistance provided is arranged, characterized in that the bridging impedance of the series arm is divided into several (n) parallel connected two-poles is, each of the series connection of a fixed resistor (R) and the input resistance of an auxiliary quadrupole (KPI ... KPn), which is terminated with a variable resistor ( W ₁ ... W _n ) , and that the shunt arm impedance dual to the bridging impedance is (Figs. 1 and 2). 2. Bode equalizer according to claim 1, characterized in that the auxiliary four-pole (KPI ... KPii) are designed as bridged T-links, in which the bridging resistance and the shunt arm resistance are dual to one another (Fig. 1 and 2). 3. Bode equalizer according to claim 2, characterized in that the standardized fixed resistances (R) are equal to / i times the product of the basic attenuation factor reduced by one times the basic attenuation factor reduced by one (11-11 times the basic attenuation factor (\ divided by the reduced by one (2; i - l) -fold basic attenuation factor and that the normalized wave resistances (W ₁ ,) of the auxiliary quadrupoles in the transfer branch are equal to the ii ² -fold basic attenuation factor times the basic attenuation factor reduced by one, divided by the reduced by one (2; i - 11 times the basic damping factor [Fig. 2: equations (6) and (7)]. 4. Bode equalizer made from a bridged T-section. in which the bridging impedance from the parallel connection of a fixed resistor and the input resistance of an auxiliary quadrupole with the correct characteristic impedance provided with a variable terminating resistor and the shunt arm impedance from the series connection of a further fixed resistor and the input resistance of a further wave resistance correct, characterized by the fact that the two auxiliary quadripoles provided are characterized by having variable terminating resistance (KPI and KPII) have different transfer rates, so that the normalized fixed resistance (R \) of the bridging impedance is equal to the product of the basic attenuation factor reduced by one and the circular attenuation factor increased by three. divided by three minus the basic attenuation factor, that the normalized fixed resistance ( R2) in the shunt branch is the reciprocal of the resistance to the normalized fixed resistance (Al) in the bridging branch, that the normalized wave resistance (H ^ i) of the auxiliary quadrupole (KPI) in the bridging branch is equal to the product of the um one reduced basic attenuation factor and the basic attenuation factor increased by three. divided by twice the basic attenuation factor and that the normalized wave resistance (W ₀₂ ) of the auxiliary quadrupole (KPII) in the shunt branch is reciprocal to the normalized wave resistance (W _m ) of the auxiliary quadrupole in the bridging branch [Fig. 3; Equations (9) to (12) 1. 5. Bode equalizer according to one of the preceding claims, characterized in that the bridged T-members of the auxiliary four-pole all-pass members, especially in the form of cross members, are downstream.