Standing wave damping on a waveguide carrying a signal

Abstract

A device for damping a standing wave on a waveguide carrying a signal is provided. The device includes at least one pair of an impedance-up-transforming and an impedance-down-transforming Boucherot bridge is connected into the waveguide. The two Boucherot bridges bring about locally increased impedances and inductance values, with the result that a significantly improved standing wave suppression or damping is obtained. The down-transforming Boucherot bridge is connected directly behind the up-transforming bridge, with the result that down-transformation to the original impedance of the waveguide again can be carried out and a signal reflection can thus be avoided.

Claims

1. A device for damping a standing wave on a waveguide carrying a signal in a propagation direction and having an impedance, comprising: an input feeding the signal from the waveguide into the device; an output outputting the signal from the device into the waveguide; one or more groups of bridge arrangements, wherein each bridge arrangement of each group of bridge arrangements are connected in series between the input and the output of the device, wherein each bridge arrangement of each group of bridge arrangements are impedance-transforming Boucherot bridge arrangements, and wherein each bridge arrangement of the plurality of bridge arrangements has an impedance greater than an impedance of the waveguide.

2. The device of claim 1, wherein each group of bridge arrangements pass the signal through each respective group of bridge arrangements without signal reflections.

3. The device of claim 1, wherein each group of bridge arrangements of each respective group of bridge arrangements comprise: an impedance up-transformation from an input impedance to a respective intermediate impedance, wherein the respective intermediate impedance is higher than the input impedance; and an impedance down-transformation from the respective intermediate impedance to a lower impedance.

4. The device of claim 3, wherein at least one group of the impedance up-transformation from the input impedance to the respective intermediate impedance comprises a different number of transformation steps than the impedance down-transformation from the respective intermediate impedance to the lower impedance.

5. The device of claim 1, wherein at least one group of bridge arrangements comprises: more than two bridge arrangements, wherein, as viewed in the propagation direction of the signal through the device, the first bridge arrangement of the at least one group has a higher impedance than the last bridge arrangement of the group of bridge arrangements.

6. The device of claim 1, wherein at least one group of bridge arrangements comprises: more than two bridge arrangements, wherein, as viewed in the signal propagation direction of the signal through the device, the first bridge arrangement of the at least one group of bridge arrangements has a lower impedance than the last bridge arrangement of the at least one group.

7. The device of claim 1, wherein at least one group of bridge arrangements comprises: a pair of bridge arrangements, wherein the impedances of the two bridge arrangements of the pair are identical.

8. The device of claim 1, wherein each bridge arrangement comprises at least one Boucherot bridge, at least one of the bridge arrangements, or at least one Boucherot bridge and at least one of the bridge arrangements comprises: a plurality of Boucherot bridges configured and interconnected with one another in such a way that the one bridge arrangement has a predefined total impedance value.

9. The device of claim 1, wherein at least one group of bridge arrangements comprises: at least two successive bridge arrangements of the respective group of bridge arrangements are directly connected to one another.

10. The device of claim 1, wherein each bridge arrangement of a group of bridge arrangements are directly and respectively connected to one another.

11. The device of claim 1, comprising: at least a first plurality of Boucherot bridge arrangements; a second plurality of Boucherot bridge arrangements; and a line connecting a last bridge arrangement of the first plurality of Boucherot bridge arrangements in the signal flow direction to a first bridge arrangement of the second plurality of Boucherot bridge arrangements in the propagation direction of the signal.

12. The device of claim 2, wherein each group of bridge arrangements of each respective group of bridge arrangements comprise: an impedance up-transformation from an input impedance to a respective intermediate impedance, wherein the respective intermediate impedance is higher than the input impedance; and an impedance down-transformation from the respective intermediate impedance to a lower impedance.

13. The device of claim 2, wherein at least one group of bridge arrangements comprises: more than two bridge arrangements, wherein, as viewed in the propagation direction of the signal through the device, the first bridge arrangement of the at least one group has a higher impedance than the last bridge arrangement of the group of bridge arrangements.

14. The device of claim 3, wherein at least one group of bridge arrangements comprises: more than two bridge arrangements, wherein, as viewed in the propagation direction of the signal through the device, the first bridge arrangement of the at least one group has a higher impedance than the last bridge arrangement of the group of bridge arrangements.

15. The device of claim 4, wherein at least one group of bridge arrangements comprises: more than two bridge arrangements, wherein, as viewed in the propagation direction of the signal through the device, the first bridge arrangement of the at least one group has a higher impedance than the last bridge arrangement of the group of bridge arrangements.

16. The device of claim 2, wherein at least one group of bridge arrangements comprises: more than two bridge arrangements, wherein, as viewed in the signal propagation direction of the signal through the device, the first bridge arrangement of the at least one group of bridge arrangements has a lower impedance than the last bridge arrangement of the at least one group.

17. The device of claim 3, wherein at least one group of bridge arrangements comprises: more than two bridge arrangements, wherein, as viewed in the signal propagation direction of the signal through the device, the first bridge arrangement of the at least one group of bridge arrangements has a lower impedance than the last bridge arrangement of the at least one group.

18. The device of claim 4, wherein at least one group of bridge arrangements comprises: more than two bridge arrangements, wherein, as viewed in the signal propagation direction of the signal through the device, the first bridge arrangement of the at least one group of bridge arrangements has a lower impedance than the last bridge arrangement of the at least one group.

19. The device of claim 2, wherein at least one group of bridge arrangements comprises: a pair of bridge arrangements, wherein the impedances of the two bridge arrangements of the pair are identical.

20. The device of claim 3, wherein at least one group of bridge arrangements comprises: a pair of bridge arrangements, wherein the impedances of the two bridge arrangements of the pair are identical.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 illustrates one exemplary system for a device 100 for damping standing waves,

(2) FIG. 2 illustrates one embodiment of the device for damping a standing wave,

(3) FIG. 3 illustrates a second embodiment of the device for damping a standing wave in one variant,

(4) FIG. 4 illustrates the embodiment of the device of FIG. 3 for damping a standing wave in a second variant,

(5) FIG. 5 illustrates yet another embodiment of the device for damping a standing wave,

(6) FIG. 6 illustrates the construction of a Boucherot bridge arrangement in one embodiment,

(7) FIG. 7 illustrates the construction of a Boucherot bridge arrangement with multiple Boucherot bridges,

(8) FIG. 8 illustrates an equivalent circuit diagram of the device for a push-pull signal,

(9) FIG. 9 illustrates an equivalent circuit diagram of the device for determining the damping for a common-mode signal.

DETAILED DESCRIPTION

(10) Identical reference signs in different figures identify identical component parts except where otherwise indicated.

(11) FIG. 1 illustrates one exemplary application for a device 100 for damping standing waves on a waveguide 10 having an impedance Z1. The waveguide 10 is used to conduct an electrical signal S from a source 1 to a load 2. The propagation direction of the signal S is represented by an arrow P. In the application shown in FIG. 1, the source 1 is a receiving coil of a magnetic resonance imaging apparatus (MRI, not shown), and a module 2 of the MRI for signal processing represents the load 2. The waveguide 10 is a two-pole signal-carrying line comprising a first wire 11 and a second wire 12, that may be embodied as a coaxial line 10. The first wire 11 can represent the ground of the coaxial line 10, while the second wire 12 is the inner conductor of the coaxial line 10. The receiving coil 1 and also the signal processing module 2 are not illustrated in detail and will not be described any further at this juncture. Embodiments are contemplated to be usable and applicable in other applications.

(12) In the operating state of the MRI, the waveguide 10 conducts the electrical signal S from the receiving coil 1 to the signal processing module 2. As described in the introduction, a disturbing standing wave can form on the coaxial line 10. In order to dampen or completely suppress such a standing wave, the device 100 is used. Device 100 is integrated between a first section 10A and a second section 10B of the waveguide 10.

(13) FIG. 2 illustrates an embodiment of the device 100 for damping a standing wave on the waveguide 10. The waveguide 10 here consists of a first section 10A having an impedance Z1A and a second section 10B having an impedance Z1B. As is customary in the art, Z1A=Z1B=Z1=50 is assumed below.

(14) The damping device 100 comprises an input 101, via which the signal S from the first section 10A of the waveguide 10 is fed into the device 100, and an output 102, via which the signal S is output from the device 100 into the second section 10B of the waveguide 10. The first section 10A, the device 100 and the second section 10B are therefore connected in a cascade in the signal propagation direction P.

(15) Furthermore, the damping device 100 comprises a first pair 110 of cascade-connected impedance-transforming Boucherot bridge arrangements BBup1, BBdn1 having corresponding impedances Z_up1 and Z_dn1, respectively. The bridge arrangements BBup1, BBdn1 are connected to one another via a line W1 having an impedance Z_W1. Ideally, the bridge arrangements BBup1, BBdn1 are directly connected to one another.

(16) In this case, a direct connection is provided e.g., if the connected bridge arrangements BBup1, BBdn1 are spatially so closely adjacent that for the length X of the connection line necessary for producing the connection it holds true that X<</4, wherein X is the wavelength of the signal, S. When this relationship is maintained, the impedance of the connection line is also irrelevant.

(17) The signal S fed into input 101 is fed to the first pair 110 of impedance-transforming Boucherot bridge arrangements BBup1, BBdn1, wherein the bridge arrangements BBup1, BBdn1 are configured by selection of the required capacitances and inductances in such a way that the bridge BBup1 passed through first in the signal propagation direction P has an impedance-up-transforming effect and the bridge BBdn1 passed through second in the signal propagation direction P has an impedance-down-transforming effect.

(18) Boucherot bridges and also cables are passive, reciprocal systems with regard to signal propagation direction. Signals can thus pass through these systems in the forward direction and in the reverse direction and have the same damping values in the case of losses in both directions. As described above, a Boucherot bridge having an impedance ZB=sqrt(Z1*Z2) provides reflection-free transmission of a signal from a line having an impedance Z1 to a line having an impedance Z2. In this case, the direction of the signal passing through the bridge is unimportant. As used herein, signal propagation direction, P, is used merely for explanation purposes, and does not imply that a signal may travel in one direction only.

(19) The Boucherot bridge arrangement BBup1 is connected on the input side to the first section 10A of the waveguide 10 and on the output side to the line W1 or directly to BBdn1. The Boucherot bridge arrangement BBdn1 is connected to the line W1 or directly connected to BBup1 and the second section 10B of the waveguide 10. As explained in the introduction, Z_up1=sqrt(Z1A*Z_W1)=sqrt(Z1*Z_W1) and Z_dn1=sqrt(Z_W1*Z1B)=sqrt(Z_W1*Z1) accordingly hold true, avoiding signal reflections. The impedance Z_W1 is accorded the role of an intermediate impedance ZW=Z_W1.

(20) Ideally, the bridge arrangements BBup1, BBdn1 are directly connected to one another.

(21) A damping of a standing wave on the waveguide 10 is then achieved because an increased impedance for the potential standing wave can be generated locally by the device 100, said impedance being at least higher than the impedance Z1 of the waveguide 10. For this purpose, the two Boucherot bridge arrangements BBup1, BBdn1 are configured in such a way that their impedances Z_up1, Z_dn1 are greater than the impedance of the waveguide 10, e.g. Z_up1>Z1, Z_dn1>Z1. Thus, higher inductance values of the Boucherot bridge arrangements result, having an advantageous effect on the damping of the standing wave.

(22) The device 100 design of two Boucherot bridge arrangements BBup1, BBdn1, that firstly up-transformation (e.g., from Z1A=Z1=50 to ZW=Z_W1=500) is effected with the aid of the impedance-up-transforming bridge arrangement BBup1, bringing about an effective damping of the standing wave with high intermediate impedance ZW=500. Furthermore, down-transformation again from the intermediate impedance ZW=500 back to Z1B=Z1=50 is effected with the aid of the impedance-down-transforming bridge arrangement BBdn1 in order to achieve a matching to the waveguide 10, or the second section 10B, such that the signal S can be fed in a manner free of reflections from the bridge arrangement BBdn1 into the second section 10B of the waveguide 10. If the impedances Z1A, Z1B of the first section 10A and of the second section 10B of the waveguide 10 are identical, the impedances Z_up1 and Z_dn1 of the embodiment, shown in FIG. 2, are likewise identical, e.g. Z_up1=Z_dn1.

(23) FIG. 3 illustrates a second embodiment of the device 100 for damping a standing wave on the waveguide 10. The damping device 100 once again includes an input 101. The signal S from the first section 10A of the waveguide 10 is fed into the device 100 via input 101. The signal S is output from the device 100 into the second section 10B of the waveguide 10 via an output 102.

(24) In addition to the first pair 110 of Boucherot bridge arrangements BBup1 and BBdn1 as explained in association with FIG. 2, the device in the second embodiment includes a further pair 120 of cascade-connected impedance-transforming Boucherot bridge arrangements BBup2, BBdn2 having corresponding impedances Z_up2 and Z_dn2, respectively. The signal S that leaves the Boucherot bridge arrangements BBdn1 of the first pair 110 is fed to the Boucherot bridge arrangement BBup2 and then to the Boucherot bridge arrangement BBdn2 of the further pair 120. Accordingly, a cascade connection of the first section 10A of the waveguide 10, the first pair 110 of bridge arrangements BBup1, BBdn1, the further pair 120 of bridge arrangements BBup2, BBdn2 and the second section 10B of the waveguide 10 arises in the signal propagation direction P.

(25) The functioning of the second pair 120 and of the associated bridge arrangements BBup2 and BBdn2 corresponds to the functioning of the first pair 110. The bridge arrangements BBup2, BBdn2 are configured by selection of the required capacitances and inductances in such a way that the bridge BBup2 passed through first in the signal propagation direction P has an impedance-up-transforming effect and the bridge BBdn2 passed through second in the signal propagation direction P has an impedance-down-transforming effect.

(26) In the second embodiment shown in FIG. 3, the Boucherot bridge arrangement BBup1 of the first pair 110 is connected to the first section 10A of the waveguide 10 and via a line W1 or directly to the Boucherot bridge arrangement BBdn1, while the Boucherot bridge arrangement BBdn1 is furthermore connected via a line W2 or, if appropriate, directly to the Boucherot bridge arrangement BBup2. The Boucherot bridge arrangement BBup2, for its part, is connected via a line W3 or directly to the Boucherot bridge arrangement BBdn2 that is finally connected to the second section 10B of the waveguide 10. The lines W1, W2, W3 in this case have impedances Z_W1, Z_W2, Z_W3.

(27) As explained in the introduction, the following relationships result: Z_up1=sqrt(Z1A*Z_W1), Z_dn1=sqrt(Z_W1*Z_W2), Z_up2=sqrt(Z_W2*Z_W3), Z_dn2=sqrt(Z_W3*Z1B). Given a corresponding design of the bridge arrangements BBup1, BBdn1, BBup2, BBdn2 e.g. by selection of suitable parameters of the capacitances and inductances that form the bridges, provides that the signal S can pass through the device 100 in a manner free of reflections.

(28) Here, too, the impedances Z_W1, Z_W2, Z_W3 are accorded the roles of intermediate impedances ZW1=Z_W1, ZW2=Z_W2, ZW3=Z_W3. For the case where the first pair 110 and the second pair 120 of bridge arrangements BBup1, BBdn1, BBup2, BBdn2 are arranged at a distance from one another in the waveguide 10. It may be assumed that the line W2 connecting the two pairs 110, 120 to one another corresponds to the waveguide 10 and has a corresponding impedance Z_W2=Z1. Therefore, the impedance Z_W2 is not higher than the impedance of the waveguide 10.

(29) In practice, multiple such pairs of Boucherot bridge arrangements may be arranged in a manner distributed over the waveguide at mutual distances of 30-40 cm.

(30) A damping of a standing wave on the waveguide 10 is then again achieved via locally increased impedances generated by the device 100. For this purpose, the Boucherot bridge arrangements BBup1, BBdn1, BBup2, BBdn2 are configured in such a way that their impedances Z_up1, Z_dn1, Z_up2, Z_dn2 are greater than the impedance of the waveguide 10, e.g. Z_up1>Z1, Z_dn1>Z1, Z_up2>Z1, Z_dn2>Z1. Higher inductance values of the Boucherot bridge arrangements result, having an advantageous effect on the damping of the standing wave.

(31) When the two pairs 110, 120 are arranged at a distance from one another in the waveguide 10 and are correspondingly connected via a further section W2=10C of the waveguide, Z_W2=Z1 would ideally hold true. It may again be assumed that Z1A=Z_W2=Z1 or Z_W2=Z1B=Z1, such that the impedances of the bridge arrangements BBup1, BBdn1 are identical, e.g. Z_up1=Z_dn1=Zx. The same applies to the impedances of the bridge arrangements BBup2, BBdn2, e.g. Z_up2=Z_dn2=Zy. At the same time it is also possible, however, for the impedances of the bridge arrangements of the different pairs 110, 120 to be different, e.g. ZxZy, such that the intermediate impedance ZW1 for the first pair 110 differs from the intermediate impedance ZW3 for the second pair 120.

(32) The device 100 with the described use and design of two pairs 110, 120 of Boucherot bridge arrangements BBup1, BBdn1 and BBup2, BBdn2, respectively, such that a first transformation e.g. from Z1A=Z1=50 to ZW1=500 is effected with the aid of the impedance-up-transforming bridge arrangement BBup1, bringing about a first effective damping of the standing wave. Transformation from the intermediate impedance ZW1=500 to the further intermediate impedance ZW2=Z_W2 can be effected with the aid of the impedance-down-transforming bridge arrangement BBdn1.

(33) For embodiments where the two pairs 110, 120 are arranged at a distance from one another in the waveguide 10 and are also accordingly connected via a further section W2=10C of the waveguide, ZW2=Z_W2=Z1=50 holds true for the further intermediate impedance. In order to achieve this, the impedances Z_up1, Z_dn1 are identical again. In the first transformation, bridge arrangement BBup2, e.g. from Z_W2=Z1=50 to ZW3=700 is effected with the aid of the impedance-up-transforming bridge arrangement BBup2, causing a second effective damping of the standing wave.

(34) With regard to complexity and production of the device 100, it may be preferable for the first and second pairs 110, 120 to include an up-transformation to the same intermediate impedance, e.g. to 600, since different component values would not be required.

(35) In another example, the two pairs 110, 120 are a distance from one another such that the length X_W2 of the line W2 does not maintain the relationship X_W2<</4. Instead, the impedances Z_up1, Z_dn1 may be different, such that Z_W2=ZW2>Z1 holds true. The following bridge arrangement BBup2 can be configured such that, although the intermediate impedance ZW3 is greater than Z1, it is also less than or greater than ZW2. Therefore, an effective damping of a standing wave is brought about via different bridge impedances and, associated therewith, via different increased inductance values.

(36) In both examples, the subsequent impedance-down-transforming bridge arrangement BBdn2 is configured in such a way that it effects down-transformation from the intermediate impedance ZW3=Z_W3 back to Z1B=Z1=50 in order to achieve a matching to the second section 10B of the waveguide 10, such that the signal S can pass free of reflections from the bridge arrangement BBdn2 into the second section 10B.

(37) Without departing from the basic concept of the second embodiment illustrated in FIG. 3, it is possible, to arrange more than two pairs of Boucherot bridge arrangements in the waveguide 10. This plurality of pairs can then be arranged in a manner distributed over the waveguide 10 at identical distances, wherein each pair, per se, operates in the manner described in association with the embodiment depicted in FIG. 2 and the bridge arrangements of each pair are ideally directly connected to one another.

(38) The second embodiment including a plurality of pairs 110 and 120 of bridge arrangements may be realized in a plurality of variants that differ in the order of the individual bridge arrangements in the signal propagation direction P. The embodiment depicted in FIG. 3 may correspond to a first variant of the second embodiment, where the individual bridge arrangements of the first and second pairs 110, 120 are cascade-connected in such a way that the signal passes through first the impedance-up-transforming Boucherot bridge arrangement BBup1 of the first pair 110, then the impedance-down-transforming Boucherot bridge arrangement BBdn1 of the first pair 110, then the impedance-up-transforming Boucherot bridge arrangement BBup2 of the second pair 120 and then followed by the impedance-down-transforming Boucherot bridge arrangement BBdn2 of the second pair 120.

(39) The second embodiment in the first variant is particularly suitable where the two pairs 110, 120 are separated by a distance from one another in the waveguide 10, since it is possible to effect down-transformation from the high intermediate impedance ZW1 to the normal impedance Z1 of the waveguide 10 using the impedance-down-transforming bridge arrangement BBdn1 of the first pair 110. As a result, the first pair 110 may be connected to the second pair 120 separated at a distance by line W2 having the same properties of the waveguide 10, such that the useful signal S is not reflected during transmission via the line W2.

(40) A second variant of the second embodiment is illustrated in FIG. 4. In the second variant, the individual impedance-transforming Boucherot bridge arrangements BBup1, BBdn1 and BBup2, BBdn2 of the first and second pairs 110, 120, respectively, are cascade-connected causing the signal S from the first section 10A firstly passes through the impedance-up-transforming Boucherot bridge arrangement BBup1 of the first pair 110. The signal then passes via a line W1 having an impedance Z_W1 or directly to the impedance-up-transforming Boucherot bridge arrangement BBup2 of the second pair 120. The signal S then passes via a line W2 having an impedance Z_W2 or directly to the impedance-down-transforming Boucherot bridge arrangement BBdn1 of the first pair 110. Then, directly connected or connected via a line W3 having an impedance Z_W3, Signal S reaches the impedance-down-transforming Boucherot bridge arrangement BBdn2 of the second pair 120. Signal S is then fed from into the second section 10B of the waveguide 10.

(41) In the second variant of the second embodiment, the individual bridge arrangements may be configured in such a way that the signal S can pass through the bridges in a manner free of reflections. As explained, the following relationships result: Z_up1=sqrt(Z1A*Z_W1), Z_up2=sqrt(Z_W1*Z_W2), Z_dn1=sqrt(Z_W2*Z_W3), Z_dn2=sqrt(Z_W3*Z1B). Given a corresponding design of the bridge arrangements BBup1, BBdn1, BBup2, BBdn2, e.g. by selection of suitable parameters of the capacitances and inductances that form the bridges, the signal S can pass through the device 100 in a manner free of reflections.

(42) The second variant of the second embodiment is less suitable when the pairs or the individual bridge arrangements are arranged in a manner distributed over the waveguide 10 in a spaced-apart fashion because each intermediate impedance may be considerably greater than the impedance of the waveguide 10, such that a line W1, W2, and/or W3 connecting two successive bridge arrangements would correspondingly reflect the useful signal. In order to minimize this influence, the lines W1, W2, W3 are as short as possible or the bridge arrangements may be directly connected to one another, such that a distribution over the waveguide 10 may not be practical.

(43) An effective damping of standing waves is then achieved again via the fact that locally increased impedances are generated by the device 100. For this purpose, the Boucherot bridge arrangements BBup1, BBup2, BBdn1, BBdn2 are configured in such a way that their impedances Z_up1, Z_up2, Z_dn1, Z_dn2 are greater than the impedance of the waveguide 10, e.g. Z_up1>Z1, Z_dn1>Z1, Z_up2>Z1, Z_dn2>Z1. Higher inductance values of the Boucherot bridge arrangements are thus achieved, having an advantageous effect on the damping of the standing wave.

(44) In both variants of the second embodiment described, the device 100 includes more than two Boucherot bridge arrangements. In the context of the description of the figures, pairs of Boucherot bridge arrangements have specifically been mentioned. For example, the second variant of the second embodiment, with two impedance-up-transforming Boucherot bridge arrangements BBup1, BBup2 and respectively two impedance-down-transforming Boucherot bridge arrangements BBdn1, BBdn2 are disclosed as connected directly one behind another. However, the second variate of the second embodiment, along with other embodiments and variants may also be realized with an odd number of bridge arrangements. By way of example, the two up-transforming bridge arrangements BBup1, BBup2 may be replaced by a single up-transforming bridge arrangement BBUP. Alternatively, the two down-transforming bridge arrangements BBdn1, BBdn2 can analogously be replaced by a single down-transforming bridge arrangement BBDN. This accordingly has the result that the device no longer comprises pairs of Boucherot bridge arrangements, but rather, groups of Boucherot bridge arrangements, wherein each group comprises one or more Boucherot bridge arrangements.

(45) FIG. 5 illustrates a third embodiment providing a group 130 of Boucherot bridge arrangements BBup1, BBdn1, BBdn2. The group 130 comprises an odd number of cascade-connected Boucherot bridge arrangements BBup1, BBdn1, BBdn2 having impedances Z_up1, Z_dn1, Z_dn2. BBup1 is connected to BBdn1 via a line W1 having an impedance Z_W1 or may be directly connected to BBdn1. BBdn1 is connected to BBdn2 via a further line W2 having an impedance Z_W2 or directly connected to BBdn2. The signal S from the first section 10A passes through the impedance-up-transforming Boucherot bridge arrangement BBup1, then passes directly or through line W1 to the impedance-down-transforming Boucherot bridge arrangement BBdn1. The signal then passes directly or through W2 to the impedance-down-transforming Boucherot bridge arrangement BBdn2. The signal S is then fed from BBdn2 into the second section 10B of the waveguide 10. Here, too, the impedances Z_W1, Z_W2 are accorded the roles of intermediate impedances ZW1=Z_W1, ZW2=Z_W2.

(46) In the third embodiment, the individual bridge arrangements may also be configured in such a way that the signal S can pass through the bridges in a manner free of reflections. As already explained, the following relationships result: Z_up1=sqrt(Z1A*Z_W1), Z_dn1=sqrt(Z_W1*Z_W2), Z_dn2=sqrt(Z_W2*Z1B). Given a corresponding design of the bridge arrangements BBup1, BBdn1, and BBdn2, it is provided that the signal S can pass through the device 100 in a manner free of reflections.

(47) The effective damping of standing waves is achieved here, too, if the Boucherot bridge arrangements BBup1, BBdn1, BBdn2 are configured in such a way that their impedances Z_up1, Z_dn1, Z_dn2 are greater than the impedance of the waveguide 10, e.g., Z_up1>Z1, Z_dn1>Z1, Z_dn2>Z1.

(48) The specific combination of one up-transforming bridge arrangement BBup1 with two down-transforming bridge arrangements BBdn1 and BBdn2 results in the first intermediate impedance ZW1 greater than the second intermediate impedance ZW2. The two-stage transformation effects transformation from the high intermediate impedance ZW1 via the lower intermediate impedance ZW2 back to the line impedance Z1.

(49) FIG. 5 illustrates an embodiment in that the impedance transformation to the higher impedance is effected in a single act with the aid of BBup1, while the transformation to the lower impedance is achieved in two acts with the aid of BBdn1 and BBdn2. Of course, other variants can also be chosen (not shown). For example, the up-transformation can be effected in two acts (e.g., transformations) and the down-transformation is effected in a single act (e.g., transformation). More than two acts for the up- and/or down-transformation may be employed. A group 130 of Boucherot bridge arrangements having at least two different intermediate impedances that are greater than the line impedance Z1 arises in any variant.

(50) FIG. 6 illustrates the construction of a Boucherot bridge arrangement 20 in one simple embodiment. Each of the previously mentioned bridge arrangements BBup1, BBup2, BBdn1, BBdn2, BBUP, BBDN can be constructed like the simple Boucherot bridge arrangement 20 shown in FIG. 6.

(51) The Boucherot bridge arrangement 20 in FIG. 6 consists of an individual Boucherot bridge 21 having two identical capacitances C and two identical inductances L. The inter-connection and functioning of these components is known, per se, from the Antennenbuch previously mentioned, and will not be explained in any greater detail.

(52) Alternatively, one or each of the Boucherot bridge arrangements BBup1, BBup2, BBdn1, BBdn2 may be constructed from a suitable interconnection of multiple individual Boucherot bridges 21, 22. The terms Boucherot bridge arrangement and/or bridge arrangement therefore encompass both the case that the respective Boucherot bridge arrangement, as illustrated in FIG. 6, consists of an individual Boucherot bridge 21, and the case shown in FIG. 7 in that the respective Boucherot bridge arrangement 20 is formed from a plurality of individual Boucherot bridges 21, 22 interconnected in a suitable manner. In both cases, the respective Boucherot bridge arrangement 20 has a predefined impedance ZB as a result of corresponding selection and inter-connection of inductances and capacitances.

(53) As illustrated in FIG. 7, Boucherot bridges 21, 22 each have two identical capacitances C1, C2 and inductances L1, L2. The individual bridges 21, 22 are identified or demarcated from one another by dashed lines.

(54) As depicted in FIGS. 6 and 7, each Boucherot bridge 21, 22, the entire Boucherot bridge arrangement 20, and thus also the device 100 may each be considered a two-port network having two inputs and two outputs.

(55) FIG. 8 illustrates the customary interconnection suitable for the transmission of a push-pull signal. The device 100 is represented by a two-port network with the two inputs and the two outputs of the two-port network respectively connected to the wires 11, 12 of the waveguide 10. The two-port network represents the device 100 and, thus, two or more of the impedance-transforming bridge arrangements described above.

(56) FIG. 9 illustrates the equivalent circuit diagram for the transmission of a common-mode signal and for determining the damping for the common-mode signal. The Boucherot bridge arrangement 20 is again represented by a two-port network, where the wires 11 and 12 of the waveguide 10 are interconnected together with the two-port network 100. The external surroundings 13 of the waveguide 10, e.g. a floor, a wall, etc., function as return conductor.

(57) In any embodiment, an impedance transformation from an input impedance, e.g., the impedance Z1 of the waveguide 10, to an intermediate impedance is carried out, wherein said intermediate impedance is greater than the input impedance, in order to achieve a better damping of the standing wave. This up-transformation can be carried out in one or more acts, e.g. with the aid of the bridge arrangements BBup1, BBup2. An impedance transformation from the intermediate impedance to a lower impedance at the output also may occur in any embodiment where the lower impedance generally corresponds to the impedance Z1 of the waveguide 10 at the input. This down-transformation can likewise be carried out in one act or in a plurality of acts, e.g. with the aid of the bridge arrangements BBdn1, BBdn2.

(58) The family of terms configured, designed, etc., in association with electrical circuits, e.g. Boucherot bridges or Boucherot bridge arrangements, relates in particular to the selection of individual components of the circuits, e.g. capacitances C, inductances L and/or resistances R, that may be made in such a way that a specific effect is obtained, e.g. a predefined impedance. The corresponding circuit is designed in that case in such a way that the predefined impedance is achieved.

(59) The intermediate impedances and the impedances of the bridge arrangements may be freely selected, in contrast to the generally predefined impedance Z1 of the waveguide 10. The higher a selected intermediate impedance, the greater the extent to which the common-mode signal is suppressed by the high inductance values of the Boucherot bridges. However, the damping for the useful signal also increases, and the bandwidth that can be transmitted decreases. In the context of an optimization, the impedance may be roughly described as a compromise solution for subsequently defining the exact impedance based on values of the available series of tolerances (e.g. E12) of the required components. The device 100 is intended for integration with installations with an operating frequency f, and the impedance Z1 of the waveguide 10 are often known values, an available standard value for the design of the Boucherot bridge arrangements may be selected for only one of either the inductances L or the capacitances C of the Boucherot bridge arrangements, while the respective unselected component may be adapted. Preferably, the standard value for the inductance L is selected, while the exact value for the capacitance C may be easily established individually by parallel connection of capacitances.

(60) It is to be understood that the elements and features recited in the appended claims may be combined in different ways to produce new claims that likewise fall within the scope of the present invention. Thus, whereas the dependent claims appended below depend from only a single independent or dependent claim, it is to be understood that these dependent claims may, alternatively, be made to depend in the alternative from any preceding or following claim, whether independent or dependent, and that such new combinations are to be understood as forming a part of the present specification.

(61) While the present invention has been described above by reference to various embodiments, it may be understood that many changes and modifications may be made to the described embodiments. It is therefore intended that the foregoing description be regarded as illustrative rather than limiting, and that it be understood that all equivalents and/or combinations of embodiments are intended to be included in this description.