DE2330239C3 - Hybrid circuit for broadband splitting of an RF signal - Google Patents

Description

H + I ' Z \

and at the connection point (3) at the beginning of the secondary winding for the other axiai-

cable to common ground potential. what z. B. is important for shielding reasons. (viii. Funk-Technik. 1969. No. 22. P. 87 ί to S75. and DT-AS 16 16 291).

The function of such known circuits requires that the feed point is always lower than either of the two consumers. In some applications that occur, however, the low resistance of the feed point is a problem. So 1. B. for double branches .. where the line carrying signals is loaded by the branch element as a high-resistance shunt impedance. The branch element must then namely have a higher resistance excess / un ·: when it is connected to the feed point of a

Consumer adaptation for a consumer 30 hybrid circuit is adapted than when adapting

with the impedance

prevails and that the ohmic resistance (R ,. 5) connected to the two connection points (2) and (3) of the consumer (Z _2. Z ₃ ) has the value H-Z ₁ , where

H 2
! Il

the turns ratio of the transformer (4) and Ζ, the impedance of the signal source.

2. Hybrid circuit according to claim I. characterized in that the ohmic resistor (/?,. 5) is connected to the two connection points (2) and (3) via a delay circuit (τ. 6).

3. Hybrid circuit according to claims I and 2. characterized in that in series with the secondary winding of the transformer (Ü. 4) a capacitance (7) and in front of the connection point (2) of a consumer (Z,) a high-pass filter (HP. 8) is connected starting with a series capacitance.

a single consumer.

The invention is based on the object of creating a hybrid circuit of the type described at the outset, in which an often troublesome low-voltage feed point is avoided and a simple structure with the conditions of the common ground potential for source and consumer. Adaptation and Ln ¹ coupling of consumers and sufficient broadband is achieved.

This object is achieved in that the beginning of the primary winding (number of turns HIi of the transformer is connected to the feed point and the end of the secondary winding (number of turns Wl) , which is galvanically separated from the primary winding, is connected to ground a consumer adaptation for a consumer with the impedance

and the other consumer at the door connection point at the beginning of the secondary winding Adaptation for a consumer with the impedance

ΙΓ ^:
H + I

No. ₁

The invention relates to a hybrid circuit for broadband splitting of an incoming RF signal at a feed point into two decoupled, impedance-matched and with the signal source to the same ground potential consumers, whose connection point prevails and that the ohmic resistance connected to both connection points the Has value H-Z ₁ , where

Il

H 2

is the winding number ratio of the transformer and Z _{1 is} the impedance of the signal source.

Fne hybrid circuit designed in this way enables

with a simple circuit structure and fulfillment of the prerequisites described, the impedance Z. of the li «na! üuelle is always higher than the impedance of the second MKiiaiH> - _n ^, chlov; er; e! rrioedun / Z desemen

Make a consumer frenzy. '"

Pn advantageous development of the invention 'Aird

_rf . see it. that the ohmic resistance over a

\> r7 ^ erun «sschaUuni £ with the, two connecting

kt * n is connected This action causes

^P -ne E "'height" of the upper limit frequencies /.

Another advantageous further development of the Emndun "consists in that in series with the secondary", irlfhm "of the transformer, a capacitance and -.or Hrn connection point of one consumer, a high-pass filter beginning with a series capacitance is connected. With this circuit arrangement, at the connection point, which is located at the beginning of the secondary connection, is also taken below the green circle /. Transformer HF signal output, which can be used particularly advantageously in the case of LMK outcoupling • n ”antenna plug sockets

The following is based on the drawing in em iX implementation example! of the invention described. It

Splits

ρ yes a. I is a circuit diagram of the diagram at the beginning

ticked the Ciabe circuit.

} .- j ι ». 2 a shark picture of the Gabclsh-posture

Invention and

Pig. 3 a circuit according to the invention Implemented broadcast radio switch.

the in F i c. 1 previously represented by the Shahun "n" one recognizes he, a Sun "according to the invention in F-g. 2. that the F _jm nsneisepunkt 1 connected Signalqucilc cmc 9 / ur PrimKklung; Transformer 4 is out IX. the primary winding is connected to the c ™ "Vc ^ hcr, n" de, where Z. means impedance of the Signalclic 9

_ls . ₌

Wind Obergurig ratio of Cbenragers 4, _.i: attenuation in dB at Cbenraeung from 1 to 2 or vice versa. a, ₃ Attenuation in dB when transmitting from 1 to 3 or vice versa. _.

xo is important. that the resistor R ₅ . 3 is evenly adapted to .eine connection points 2 and 3. one theoretical ideal circuit divides the power delivered at hm.pci ^ - point 1 without loss to the ociden

Consumer Z, and Z ₃ . _r

For a better understanding of the circuit Munki: .π

dhlnnie

For a better understanding

are followed by three revision numbers' .ernanni

¹ '

and the resulting kenndat -.- n a.:ge.-!.i. So are:

3 d.7? No. ₁

Z.
■

z _;

y 2Z _:

H.erauseraus, it can be seen that Z _{1 is} always greater ^ Z.> m. In practice, the power division of the power division with H = I «t nn.h /. ■ _;; a series connection of be.dn \, rbrau, .Kr

Z, and Z ₃ . u ,, -. r; _r , -T, / -

2 and

Z, and

his

guidelines:
Il

^χ \

M ι 1

\ Y

W ₁₂ .- = «,, - Η» log. ,, «,, ■■■".

"/

η 4 Γ

_{There is no voltage at the transformer and} therefore also at the ohmic resistor, which is located between the connection points and 3, i.e. feed at the end point 1.

In the fork according to the invention, the L beτ-iriucr Ü 4 is stress-free when the feed at connection point 2 is made. The best transmission ratios result from the transmission of

Connection point 2 to connection point 1 or vice versa, and the connection point shows the best matching behavior 2. The reason for the worse behavior in the other operational cases lies in the magnetic and dielectric losses of the core material.

This different loading behavior of the fork according to the invention can advantageously be used as a distribution circuit be used in such double taps, which are housed in antenna sockets.

The required high degree of decoupling between radio, especially VHF, and television areas can often not be done economically with frequency-selective means alone and only with greater losses to realize the transmission range. Sometimes the receiving devices already have the necessary ones Selection means, so that only decoupling precautions at all to be met. The better adaptation and transmission behavior of the TV output The connection point to be provided slims fully with the different quality requirements, how they are presented to radio and television broadcasting.

Separate measures can prevent the secondary winding of the transformer 4 or the impedance of a television set connected to connection point 2, which is not defined in the LMK area the LMK signals short-circuited at connection point 3 together with the VHF signals be removed.

For this purpose, in series with the secondary winding of the transformer 4, a suitable isolating capacitance 7 and in front of the connection point 2, a high-pass filter 8 is connected beginning with a longitudinal capacitance.

1 sheet of drawings

Claims (1)

Patent claims: i. Hybrid circuit for the broad-band splitting of an incoming RF signal at a feed point into two decoupled, impedance-matched and with the signal source to the same ground potential consumers, whose connection points are the end of the primary winding and the beginning of the secondary winding of a tightly coupled transformer with two co-rotating windings and are connected to one another by an ohmic resistance, which means that the primary winding and the beginning of the secondary winding of a tightly coupled transformer with two coherent windings are marked and are vcruuriucn to one another by an ohmic resistance. Such circuits are used, among other things, as distributors or taps in joint antenna systems. So-called hybrid circuits are known. in which an ohmic resistor is connected in parallel u _{C to a} tightly coupled economy transformer. The feed point is at the center tap of the economy transformer, while the two consumers, which are decoupled from one another and matched in terms of impedance, are connected to the outer outlets of the transformer. With this circuit net that the beginning of the primary winding (Win- 15 are the outer conductors of all connected Kon formation number W ₁ ) of the transformer (0.4) at the feed point (1) and the end of the secondary winding (number of turns W ₂ ) separated from the primary winding Grounds are connected, whereby at the connection point (2) door located at the end of the primary winding 20 the one consumer adjustment door a consumer with the impedance