DE2612758B2 - Circuit arrangement for splitting RF power - Google Patents

Description

2. Circuit arrangement according to claim 1, characterized in that each power divider (V \, V ₂ ) divides half the power P0 / 2 into two equal power parts and the two power dividers are electrically equal.

3. Circuit arrangement according to claims 1 and 2, characterized in that the connecting lines between the outputs (2 or 3) of the directional coupler (Ko) and the distributors (V ₁ or V ₂ ) are electrically of equal length.

4. Circuit arrangement according to claims 1 and 2, characterized in that the connecting lines between the distributors (V _u K ₂ ) and 4-. the inputs (2 and 3) of the directional couplers (K ₁ and K ₂ ) are electrically the same length.

5. Circuit arrangement according to claims I to 4, characterized in that all 3-dB directional couplers (K ₀ , K ₁ and K ₂ ) are the same in attenuation, 0 course, phase and reflection behavior.

6. Circuit arrangement according to one of claims 1 to 5, characterized in that all 3-dB directional couplers (K _0. K, and AT ₂ ) in their coupling

are adjustable in a known manner. r,

7. Circuit arrangement according to claims I to 6, characterized in that several Arrangements are connected in cascade.

8. Circuit arrangement according to one of claims I to 7, characterized in that the mi directional coupler (K ₀ ) in the dimensions for full power (P ₀ ) and the directional coupler (K \ ... K _n ) (Ur den «th Part of the full power (P _n ), ie on

are designed.

The invention relates to a circuit arrangement for dividing HF power into several components which are essentially equal in terms of amount and phase. Such circuit arrangements are required, for example, in transmission systems when a transmitter is to transmit its RF power to several antennas. For this purpose, either adapted T-distributors or 3-dB directional couplers have been used. Difficulties arise in both cases when transmitting a wide frequency band, because in such transmission systems it is required that the antennas in a frequency range f \: / 2 = 1 : 2 work safely and meet the following conditions:

a) The services supplied to the partial antennas via the outputs of the distributor should be according to Amount and phase be the same;

b) the attenuation of each of the outputs to the transmitter should be as great as possible and should also be a there must be a high degree of decoupling between the outputs leading to the antennas;

c) the adaptation, measured into one of the outputs, should have the lowest possible reflection factor. Conditions b) and c) become z. B. is met very well with a dual distributor designed as a 3 dB directional coupler. The cushioning to the transmitter is 3 dB and the mutual decoupling of the two outputs is greater than 25 dB. The reflection factor is also favorable, but the condition of a) becomes insufficient Fulfills.

An adapted T-distributor or multiple distributor Although it fulfills condition a) well, conditions b) and c) are only poorly fulfilled.

The invention is therefore based on the object of creating a circuit arrangement with which high-frequency energy can be split over a broadband in such a way that all 3 conditions are cifillt at the same time in an optimal way, namely while avoiding the disadvantages inherent in the known distributors.

The problem is solved by the totality of the characterizing part of claim I. specified features a) to d).

Through the branching of the services and their reunification in a further directional coupler compensation for any phase error introduced in the first directional coupler is guaranteed became. In this way it is possible to split a given RF power into any number of partial powers, The number of partial services depends on the number of branches that are used by the multiple distributors go out.

It is known from BE-PS 7 30 681 that an RF power is divided into two half powers that are phase-shifted by 90 ° by a 90 ° hybrid coupler, and this is also a combination two powers shifted by 90 ° to double the power is possible.

It is also from US-PS 34 23 688 the possibility the cross-coupling of two signal powers shifted by 90 ° to form a total power. However, this does not result in a circuit arrangement with the combination of claim features a) to d), through which the complete solution of the given task becomes possible.

An exemplary embodiment of the invention is described below with reference to the drawing. In the

The drawing shows the single figure a circuit diagram of a circuit arrangement according to the invention in the form a two-way distributor to halve the power.

In the distributor input a 3 dB directional coupler Ko is used, at whose input 1 the full transmission power To is applied, while the connection 4 is terminated with a connection resistor #>. The output connections 2 and 3 of a directional coupler K ₀ are connected to matched distributors V \ and Vi via two electrical leads of equal length. The outputs of the ι ο distributors Vi and Vi are connected to two other 3-dB directional connectors K \ and Ki of the same length via four electrical lines of equal length. The two output lines of the distributor Vj are connected to the inputs 3 of the directional couplers K ₁ and K ₂ , which in their terminations 4 have the same terminating resistances R \ bzv>. Ri are connected.

The output lines of the distributor V ₂ are connected to the terminals 2 of the directional couplers Ki or Ki , at whose terminals 1 half the electrical power Po / 2 is taken off.

The function of the circuit arrangement is as follows ⁶ *:

The d *: m directional coupler Ko offered at connection 1 is taken from connections 2 and 3 with a phase difference of 90 ° as half the power Po / 2 . This half power is divided again in the T-distributors V and Vi into four quarter powers ft / 4, the two _{quarter powers emanating from distributor V 3 being} shifted by 90 ° compared to the Vicrt powers emanating from distributor Vi. These quarter powers are fed to the directional couplers K 1 and K ₂ at ports 2 and 3. Half the power Po / 2 now appears at the output 1 of the directional couplers Ki and K ₃ , with the same phase position but a phase position shifted by 90 ° with respect to the input power P _0. The reflected power of each half antenna is recorded with a quarter of the terminating resistors Λι and Ri .

In the case of a practically implemented two-way distributor of this type, the highest deviation resulted in that observed a frequency range of less than 0.1 dB and a phase difference of less than 5 °. The decoupling of the two outputs connected to the antennas was more than 25 dB and the attenuation to the transmitter 3 dB. The reflection from an exit to the transmitter was less than 0.05.

If the available total power is to be divided into more than two partial powers, then the distributors Vi and V _{2 must} each have as many outputs π as it corresponds to the desired division and these outputs are fed in pairs to a corresponding number π of directional couplers.

For this t sheet of drawings

Claims (1)

Patent claims: 1. Circuit arrangement for dividing RF power into several according to amount and phase essentially the same proportions, characterized by the totality of the following features: a) the HF power Po to be split arrives at an input (1) of a first 3 dB directional coupler (K ₀ ), at the two output connections (2 and 3) of which two half powers Pan are present, phase-shifted by 90 °, while the fourth Connection (4) of the 3-dB directional coupler (K ₀ ) is connected to a terminating resistor which corresponds to the characteristic impedance. b) Half the powers P _0n each go to a power divider (V \, V-ϊ), so that a number of partial powers of half the powers Pan are present at each power divider output. c) Two partial powers each from one of the power dividers (V \, V ₂ ), out of phase with each other by 90 °, arrive at two inputs (2 and 3) a second 3-dB directional coupler (K2) in such a way that they add up at the output terminal (1) of the 3-dB directional coupler (K ₂ ). d) The rest respectively against each other by 90 ° - ^5-shifted services from the power dividers come in pairs on in each case two inputs (2 and 3) further 3-dB directional coupler also such that they adhere to the Ausgangsanschliissen (1) of this 3 dB Add directional coupler ^{i (l} ren.