EP2815455B1 - Coupling structure for the crossing of transfer lines - Google Patents

Description

The invention relates to a coupling structure for crossing transmission lines in a signal conductor layer of a circuit substrate, a coupling structure for crossing transmission lines for millimeter-wave or centimeter-wave signals.

STATE OF THE ART

In order to cross transmission lines for high-frequency signals, it is known to provide a circuit substrate with a plurality of metallization layers on which transmission lines formed in different metallization layers can intersect. A transmission line in a metallization layer can bridge an intersection region via a detour via another metallization layer. The disadvantage here is the additional effort for the provision of a second or further metallization.

Also known is the realization of an intersection of two transmission lines of the same metallization by means of a bridge of a discrete component. Depending on the requirements, however, this can lead to disadvantageous power losses.

J.-S. Neron, G.-Y. Delisle, "Microstrip EHF Butler Matrix Design and Realization", ETRI Journal, Volume 27, Number 6, December 2005 U.S. Patent No. 5,443,088 describes a coupling structure for crossing two transmission lines for a 36 GHz signal. The coupling structure consists of a planar cross-coupler, also referred to as a 0 dB coupler, which allows an intersection of two transmission lines with minimal coupling between them. The planar cross-coupler is a cascade of two 90 ° hybrid couplers. Such, known per se 90 ° hybrid coupler generated from an input signal at one of two input points, two 90 ° out of phase signals at its starting points.

EP 0 313 058 A2 describes an array of coaxial transmission lines and couplers that form a Butler matrix for distributing microwave electromagnetic energy to antenna elements. The Butler matrix includes phase shifters and planar couplers.

US 2009/0108954 A1 describes a circulator for simultaneous transmit and receive operation. A connection between a send port, an antenna port and a receive port will be described. The connection comprises 90 ° couplers, which divide a signal applied to one terminal to the two opposite terminals or, in the reverse signal flow direction, cause a combination of signals.

JP 61172407 A describes a coupling structure in which a signal of one terminal is distributed to four terminals, while in a signal synthesis operation, signals of the four terminals are combined and output to the former terminal.

US 4 127 831 A describes a coupler in the form of a quadrupole network forming a balanced coupler.

DISCLOSURE OF THE INVENTION

The object of the invention is to provide a coupling structure for crossing three transmission lines, in particular for signals in the range of 76 to 77 GHz in a signal conductor layer of a circuit substrate.

A contribution to the achievement of this object is achieved according to the invention by a coupling structure for crossing three transmission lines for millimeter-wave or centimeter-wave signals in a signal conductor layer of a circuit substrate comprising three planar cross-couplers, each having two first input / output points and two second input / output Have starting points of the respective cross-coupler, wherein each of the three cross-coupler two in the plane of the cross-coupler successive input / output points of the cross-coupler are connected to one input / output point of each other of the three cross coupler. From each of the three cross-couplers form the other two input / output points input / output points of the coupling structure, wherein on a first side of the coupling structure three transmission lines are connected to one of the input / output points of the coupling structure, and wherein on another side of the Coupling structure continuations of the three transmission lines are connected in reverse order with one of the input / output points of the coupling structure. The signal conductor layer is preferably a metallization layer of the circuit substrate.

This coupling structure makes it possible, in particular, for the abovementioned, consecutive input / output points of a respective cross-coupler in the same signal conductor layer to be connected in each case to an input / output point of a respective other one of the three cross-couplers. Thus, a coupling structure for crossing three transmission lines can be realized within a single signal conductor layer, in which the coupling structure has no components arranged outside the signal conductor layer, in particular no discrete components.

Such a coupling structure can be advantageously used, for example, in analog and / or digital circuits for radar sensors, in which signals in the corresponding frequency range within a metallization layer are to intersect.

Further advantageous embodiments of the invention are specified in the subclaims.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the invention are illustrated in the drawings and explained in more detail in the following description.

Fig. 1

eine schematische Darstellung einer erfindungsgemäßen Koppelstruktur;

Fig. 2

eine schematische Darstellung eines weiteren Beispiels einer erfindungsgemäßen Koppelstruktur;

Fig. 3

eine schematische Darstellung eines Kreuzkopplers in Form eines 90°-Hybrid-Kopplers;

Fig. 4

eine schematische Darstellung dreier durch eine erfindungsgemäße Koppelstruktur gekreuzter Übertragungsleitungen; und

Fig. 5

eine schematische Darstellung eines Schichtaufbaus eines Schaltungssubstrates.

Show it:

Fig. 1

a schematic representation of a coupling structure according to the invention;

Fig. 2

a schematic representation of another example of a coupling structure according to the invention;

Fig. 3

a schematic representation of a cross coupler in the form of a 90 ° hybrid coupler;

Fig. 4

a schematic representation of three crossed by a coupling structure according to the invention crossed transmission lines; and

Fig. 5

a schematic representation of a layer structure of a circuit substrate.

DETAILED DESCRIPTION OF EMBODIMENTS

Fig. 1 and Fig. 2 show different examples of coupling structures 10, 10 'for crossing three transmission lines 11, 12, 13 for signals S1, S2 and S3 in the range of 76 to 77 GHz according to the schematic representation in FIG Fig. 4 , From a first circuit side, in Fig. 1 . Fig. 2 and Fig. 4 each left, are for three signals S1, S2, S3 in this order side by side arranged signal lines 11, 12, 13 ( Fig. 4 ) are each connected to an input / output point 21, 22, 23. On the opposite side of the coupling structure 10 are continuations of the three signal lines 13 ', 12', 11 ', for the signals S3, S2, S1, each with an input / output point 26, 25, 24 of the coupling structure 10 connected in reverse order. The signals applied to the input / output points 21, 22, 23 of one side of the coupling structure are transmitted to the input / output points 26, 25, 24 of the other side of the coupling structure 10 in such a way that the order of the signals (ie the order in FIG the arrangement of the signal paths next to each other) is reversed. In the Fig. 1 . 2 and 4 are the corresponding sides of the coupling structure 10 and 10 'delimited by a dashed line from each other.

Fig. 1 shows a first example of a coupling structure 10 accordingly Fig. 4 , The coupling structure 10 consists of three planar cross-couplers 30, 40, 50, which are connected to each other in a star shape and are arranged in a same signal conductor layer of a circuit substrate. Two adjacent first input / output points 31, 32 of a first cross-coupler 30 form the input / output points 21, 22 of the coupling structure, two adjacent first input / output points 41, 42 of a second cross coupler 40 form the input / output points 23, 24 of Coupling structure, and two adjacent first input / output points 51, 52 of a third cross-coupler 50 form input / output points 25, 26 of the coupling structure 10th

On an opposite side of the respective cross-couplers 30, 40, 50 are juxtaposed second input / output points 33, 34 of the first cross coupler at circuit points B, A, each having a second input / output point 44 and 53 of a respective other cross coupler 40, 50 of three cross-couplers are connected directly in the same signal conductor layer, and another second input / output points 43 of the second cross-coupler is connected at a node C to another second input / output 54 of the third cross-coupler 50 directly in the same signal conductor layer.

Thus, in each case two adjacent first input / output points 31, 32; 41, 42; or 51; 52 of a respective cross-coupler 30, 40, 50 input / output points 21 to 26 of the coupling structure, and on an opposite side of the respective cross-coupler 30, 40, 50 adjacent second input / output points 33, 34; 43, 44; or 53, 54 of the cross-coupler are each provided with a second input / output point 44, 53; 54, 33; or 34, 43 of a respective other of the three cross-couplers 30, 40, 50 connected directly in the same signal conductor layer.

The coupling structure 10 formed thereby couples the signals S 1, S 2, S 3 supplied in this order on the first side via the input / output points 21, 22, 23 to the input / output points 26, 25, 24 on the opposite side of the coupling structure 10 in reverse order. By a suitable design of the individual sections or conductor sections of the coupling structure 10 and the individual sections or conductor sections of the cross-couplers 30, 40, 50, the geometry of the coupling structure 10 and the individual cross-couplers 30, 40, 50 are optimized so that overlap the shares of each desired signal S3, S2 and S1 constructively to the input / output points used as output 26, 25, 24 and the shares of each Overlay other signals destructively. In particular, the electrical lengths and line impedance are set appropriately. This can be achieved for a given substrate by adjusting line lengths and line widths. In this way, an intersection of the three signal lines 11, 12, 13 can be achieved with the least possible mutual interference of the signals.

Fig. 2 shows a second example of a coupling structure 10 'according to the invention, which also includes three planar cross-couplers 30, 40, 50. The cross-couplers are arranged one behind the other, wherein a first cross-coupler 30 on the first side of the coupling structure 10 'two first input / output points 31, 32 of the cross coupler 30 for signals S1, S2, the input / output points 21, 22 of the coupling structure 10' , coupled with arranged in reverse order second input / output points 33, 34 of the cross coupler 30. A second input / output point 33 of the first cross-coupler 30 is connected at a circuit point D directly to a first input / output point 41 of a second, subsequent cross coupler 40 whose other first input / output point 42 is assigned to the signal S3 and the input / Starting point 23 of the coupling structure 10 'corresponds. The second cross-coupler 40 is connected to that second input / output point 33 of the first cross-coupler 30, which is opposite to the first input / output point 31 for the signal S1 diagonally. Accordingly, on the described side of the coupling structure 10 ', the signals S1, S2, S3 are supplied side by side in this order.

The node D is coupled via the second cross-coupler 40 with a diagonally opposite second input / output point 43 of the second cross coupler 40 for the signal S1, which corresponds to the input / output point 24 of the coupling structure 10 '. Accordingly, via the second cross-coupler 40, the signal S3 present at the other first input / output point 42 of the second cross-coupler 40 is connected directly to a second input / output point 54 of the third cross-coupler 50 at a diagonally opposite circuit point E in the same signal conductor position. The other second input / output point 53 of the third cross-coupler 50 is connected at a node F directly in the same signal conductor position via a signal line 58 in the form of a conductor section to the other second input / output point 34 of the first cross-coupler 30. This connection thus runs parallel to the second cross-coupler 40. Via the third cross-coupler 50, the two circuit points E, F are in turn coupled to respectively diagonally opposite first input / output points 52, 51 of the third cross-coupler 50, which correspond to the input / output points 26, 25 of the coupling structure 10 'correspond, so that in total by the coupling structure 10', the order of arrangement of the signals S1, S2, S3 is reversed.

Fig. 3 schematically shows the structure of one of the cross coupler 30, 40, 50 of the cross coupler 30 Fig. 1 or 2 , The remaining cross-couplers 40, 50 are constructed accordingly.

The cross coupler 30 is constructed as a cascade of two 90 ° hybrid couplers 60, 62, wherein at a first end of the cascading, the first input / output points 31, 32 of the cross coupler are arranged directly next to each other and at a second end of the cascading the second A - / Starting points 34, 33 are arranged directly next to each other. In the plane of the cross coupler 30, the input / output points follow each other clockwise in the order of 31, 32, 33, 34, 31,. The cross coupler 30 comprises two longitudinal connections 64, 66, which connect the input / output points 31 and 34 or 32 and 33 directly and rectilinearly, and which are interconnected by three cross-connections 68, so that a rung-shaped structure is formed with three transversal rungs , The length of the cross connections 68 is approximately one quarter of a signal wavelength in the signal line. The length of the respective sections of the longitudinal connections 64, 66 between two cross connections 68 likewise corresponds approximately to one quarter of a signal wavelength.

Both Fig. 1 and 2 In each case, at least two cross-couplers 30, 50 of the three cross-couplers each have at one end of the relevant cascade of their 90 ° hybrid couplers 60, 62 two adjacent input / output points 31, 32 or 51, 52 which form input / output points 21, 22 or 25, 26 of the coupling structure 10, 10 '. In the example of Fig. 1 this is true for each of the three cross couplers.

Fig. 5 schematically shows a structure of a circuit substrate 70, on which, for example, the coupling structure 10 or 10 'is realized. The circuit substrate 70 comprises a signal conductor layer 72 in the form of a correspondingly structured metallization layer, in which the respective coupling structure 10, 10 'is formed. Further, the circuit substrate 70 includes a carrier plate 74 in the form of a dielectric and a ground layer 76. The signal conductor layer 72 and the ground layer 76 are disposed on opposite sides of the carrier plate 74.

Claims (6)

1. Coupling structure for crossing three transmission lines (11; 12; 13) for millimetre-wave or centimetre-wave signals (S1; S2; S3) in a signal conductor layer (72) of a circuit substrate (70),

   wherein the coupling structure (10) comprises three planar cross-couplers (30; 40; 50), which each have two first input/output points (31; 32; 41; 42; 51; 52) and two second input/output points (33; 34; 43; 44; 53; 54) of the relevant cross-coupler (30; 40; 50), and

   wherein, of each of the three cross-couplers (30; 40; 50), two input/output points (33; 34; 41; 43; 44; 53; 54) of the cross-coupler (30; 40; 50) following one another in the plane of the cross-coupler (30; 40; 50) are connected to a respective input/output point (33; 34; 41; 43; 44; 53; 54) of a respective other of the three cross-couplers (30; 40; 50),

   and wherein, of each of the three cross-couplers (30; 40; 50), the respective other two input/output points (31; 32; 41; 42; 43; 51; 52) form input/output points (21; 22; 23; 24; 25; 26) of the coupling structure (10),

   and wherein, on a first side of the coupling structure (10), three transmission lines (11; 12; 13) are connected to respectively one of the input/output points (21; 22; 23) of the coupling structure (10), and

   wherein, on another side of the coupling structure (10), continuations of the three transmission lines (13'; 12'; 11') are connected in the reverse order to respectively one of the input/output points (26; 25; 24) of the coupling structure (10).
2. Coupling structure according to Claim 1, in which the cross-couplers (30; 40; 50) are each formed as a cascade of 90° hybrid couplers (60; 62).
3. Coupling structure according to Claim 2, in which at least two cross-couplers (30; 50) of the three aforementioned cross-couplers (30; 40; 50) each have, at one end of the relevant cascade, two input/output points (31; 32; 51; 52) located beside one another, which form input/output points (21; 22; 25; 26) of the coupling structure (10).
4. Coupling structure according to one of Claims 1 to 3, in which, of each of the three aforementioned cross-couplers (30; 40; 50), two input/output points (33; 34; 41; 43; 44; 53; 54) of the cross-coupler (30; 40; 50) following one another in the plane of the cross-coupler (30; 40; 50) are connected directly and in the same signal conductor layer (32) to a respective input/output point (33; 34; 41; 43; 44; 53; 54) of a respective other of the three cross-couplers (30; 40; 50).
5. Coupling structure according to one of Claims 1 to 4, in which the three cross-couplers (30; 40; 50) are arranged in the form of a star.
6. Coupling structure according to one of Claims 1 to 4, in which the three cross-couplers (30; 40; 50) are arranged sequentially one after another, wherein a second, central cross-coupler (40) is arranged laterally offset relative to a first and a third cross-coupler (30; 50), and a signal line (58) running beside the central cross-coupler (40) connects an input/output point (34) of the first cross-coupler (30) to an input/output point (53) of the third cross-coupler (50).

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