WO2017032879A1 - Hf cavity filter with a bypass line for low-frequency signals and voltages - Google Patents

Abstract

An HF filter comprises a housing with a housing bottom, a cover spaced apart from the housing bottom and a circumferential housing wall between the housing bottom and the cover (2). The cover is a circuit board (2). The HF filter comprises a common connector which is connected to the common connection (23). The HF filter also comprises at least two signal line connections, which are galvanically connected to the signal line connections (191, 192,..., 19_m). All connection contacts (191, 192,..., 19_m, 23) are located on the circuit board (2). The circuit board (2) comprises at least two bypass lines (201, 202,..., 20_m), via which the common connection contact (23) is, or can be galvanically connected or can be galvanically connected to the signal connection contacts (191, 192,..., 19_m). At least one of the bypass lines (201, 202,..., 20_m) has at least one line section (33), which is galvanically connected to at least one compensation area (31), wherein the at least one compensation area (31) represents an additional capacity in order to displace resonance frequencies from the area of usage of the HF filter.

Description

HF filter in cavity Construction with a bypass for low-frequency signals and voltages

The invention relates to an RF filter (high-frequency filter) in cavity construction with a bypass line for low-frequency signals and DC voltages. The RF filter operates preferably as a bandpass, dual ^¬ band, triple-band, or multi-band combiner.

An RF filter in this invention comprises a common terminal (dt. Common terminal) and at ^¬ least one signal line connecting, preferably at ^¬ least two signal line terminals, wherein the one Sig ^¬ nalleitungsanschluss, or at least two Signallei ^¬ line connections to the Common Connection are each interconnected via a signal transmission path. The direction of signal transmission can take place both from the common-terminal to the signal line terminal or to one of the plurality of signal line terminals (at ^¬ play, in the form of a diplexer or multiplexer), and at the same time by the signal line connection or from another one of the signal line terminals to the common terminal (for example, in the form of a duplexer in which two further terminals besides the one common terminal are provided). The respective Sig ^¬ nalübertragungspfad or the respective signal transmission fade through different resonator chambers so that different frequency ranges in this ge ^¬ be filtered out. In particular, in the reception and transmission technology, it is often common on a reception and / or transmission line not only to send or to be received high-frequency signals (hereinafter short RF signals ge ^¬ called) forward, but on this route also in the switched Antennas, amplifiers, preamplifiers, etc. integrated, active components in addition to DC supply to the power supply and / or at least also low-frequency (NF) AC voltages (for example, pilot tones) to control and regulate the components with. However, additional provided on the reception or transmission routes devices such as in particular high-frequency filters are often not capable of example ^¬ as in addition to the high-frequency signals, the additionally required for the power supply voltage and / or low-frequency AC voltage, for example for the aforementioned pilot tones to transmit and transfer. Because the problem is that such DC and / or NF-output couplings must be designed so that they mög ^¬ lichst not change the properties of the filter. This in turn only works if the bypasses to the RF lines are decoupled and therefore on the Auskoppelstrecke only extremely high attenuated high frequency signals can be transmitted. A common technique is therefore to provide a bypass in the form of a decoupling or bypass route, about what a on the high frequency track with transmitted DC voltage bwz. a low ^¬ frequency AC voltage coupled out and can be coupled at another point back into the high frequency link. As a result, for example, a high-frequency link provided with a high-frequency filter or a duplexer is bypassed or bypassed.

From WO 2007/057196 Al a high frequency filter is known, which has a direct voltage and / or low-frequency decoupling. Low-pass filters are more likely to be able to transmit the high-frequency signals via the DC voltage and / or low-frequency decoupling. By means of a wire, the DC and / or LF signals are transmitted from the decoupling point in the direction of the coupling point

The disadvantage of WO 2007/057196 Al is the high kon ^¬ constructive complexity and the fact that may be caused by the cable further resonances that fall within the useful range of the RF filter.

It is therefore the object to provide an RF filter which has a bypass line for coupling and decoupling direct voltage and / or low-frequency signals, wherein the bypass line should be simple and reproducible producible and any resonances through the bypass line not should fall into the useful range of the RF filter. The object is achieved by the RF filter according to independent claim 1. In the dependent claims advantageous developments of the RF filter according to the invention are given.

The RF filter according to the invention comprises a housing which comprises a housing bottom, a cover spaced from the housing bottom and a housing wall encircling between the housing bottom and the cover. Furthermore, at least one common pole and m Signalleitungsan ^¬ connections available, with m> 1, preferably m> 2, wherein said common terminal is connected to the signal line terminals through m m filter paths. The common terminal is a En- de of at least m filter paths coupled via a first opening in the housing with the and the m Sig ^¬ nalleitungsanschlüsse are coupled via in each case a further opening in the housing with one of the opposite m ends of the m filter paths. The cover is a printed circuit board. The printed circuit board has a common connection contact, which is galvanically connected to the common connection. The circuit board also has m signal line terminal contacts, each of the m signal line terminal contacts being galvanically connected to one of the m signal line terminals. At least one low-pass filter is arranged between the common connection and the common connection contact and / or at least one low-pass filter is respectively arranged between the m signal line connections and the m signal line connection contacts. The printed circuit board comprises m umge ^¬ tion lines, via which the common terminal connection galvanically connected to the m signal line connection contacts or connectable is. At least one of m bypass lines assigns ^¬ least a lead portion which is electrically connected to at least one compensation area, wherein the at least one compensation area is an additional Ka capacity, whereby resonances within the Lei ^¬ terplatte in frequency shifted and / or attenuated be that they no longer fall into the useful band of the RF filter. In this connection it should be also made to US 6,919,782 B2, which also describes a RF filter in the form of a cavity filter, sen ^¬ housing is closed by a housing cover that consists of a printed circuit board. One side, usually the housing interior facing side of the Lei ^¬ terplatine is galvanically coated to complete the housing frequency-tight. The printed circuit board can also be used at the same time to accommodate there further Lei ^¬ processing structures and / or components. Thus, it is described that, for example, on the Leiterpla ^¬ tine on the outside of the housing, an amplifier (LNA), a directional coupler, a low-pass structure and / or a coupling compound can be accommodated, what in addition to the galvanic terminals via which fed a signal to be transmitted or is brought out again, in addition, input or Auskoppel ^¬ places are provided in the cavity filter, which cause an electromagnetic feed while avoiding galvanic contacts.

In this case, it can be stated in summary that the above-mentioned US 6,919,782 B2 shows no Umgehungslei ^¬ tung or describes the electroplated on both Pages with two different terminals of the RF filter is in communication.

It is particularly advantageous that the bypass line for decoupling and coupling of DC and / or LF signals is arranged on a circuit board. This allows the bypass to be made easily and reproducibly. Through the use of at least one compensation area, which represents an additional capacitance and electrically connected to the at least one Conversely ^¬ hung line is connected, any resonances are shifted in such a way in its frequency range, that they no longer fall within the useful range of the RF filter.

In a further embodiment according to the invention, each of the m filter paths comprises at least:

 A resonator; and or

 At least one RF line; and or

 • a low pass or a high pass or a band pass,

 wherein these elements are designed such that no DC components and / or low-frequency signals can be transmitted.

Several resonators of a filter path are mitei ^¬ nander coupled electromagnetically. Each of the m filter paths may be implemented as a resonator or low pass DC-stop, or high-pass or band-pass or RF line with DC-stop from ^¬. The low-frequency signals in this case have a frequency which is less than 40 MHz, preferably less than 30 MHz, more preferably less than 20 MHz, more preferably less than 15 MHz, more preferably less than 10 MHz. In a further embodiment of the invention, the m bypass lines are all arranged on a first side of the circuit board. A second side of the circuit board, opposite the first side of the printed circuit board overall genüber, comprises at least at the location, the un ^¬ terhalb the basis of at least one compensation area, a ground plane which is electrically connected to the peripheral housing ^¬ wall. This second side of the circuit board is predominantly, preferably completely, covered with a ground plane which is galvanically connected to the peripheral housing wall. The printed circuit board is preferably a two-layer printed circuit board, which preferably consists of FR4 and can therefore be produced at ^low cost.

Another embodiment of this invention it purifies ^¬ that the second side of the printed circuit board is in Rich ^¬ processing of m filter paths and closes off the housing with the filter located as ^¬ rin paths. The second side therefore points in the direction of the resonator chambers which pass through the filter paths. A direct coupling of the RF signals from the filter paths into the bypass line bypassing the low-pass filter is therefore excluded.

In another embodiment according to the invention, the compensating surface is of the common

Terminal contact less than 10 cm, preferably less than 8 cm, more preferably less than 6 cm, more preferably less than 5 cm, more preferably less than 4 cm away. In addition or as an alternative, the compensation area of each of the m signal line connection contacts is less than 10 cm, preferably less than 10 cm. less than 8 cm, more preferably less than 6 cm, more preferably less than 5 cm, more preferably less than 4 cm. In a further exemplary embodiment according to the invention, the compensation surface is galvanically connected directly to the at least one line section of one of the m bypass lines. This means that the at least one line section touches the compensating surface while bypassing another intermediate line, ie adjoining it.

In an additional embodiment of the invention, the compensation surface with the at least one line section of the m bypass lines at least ei ^¬ nen common connection section. The at least one common connecting portion has a length which is greater than the average width of the bypass line. Alternatively, the at least one common connecting portion has a length greater than 70%, or 80% or 90% of the mean width of the bypass. This ensures that a sufficiently large capacity in the form of the off ^¬ equal area is added out reliably shifts the possible resonances outside the useful band of the RF filter.

In a further embodiment of the invention, the compensation surface is described in more detail. This should have a length that is greater than λ / 16, or λ / 12, or λ / 8, or λ / 4, or λ. The width should be greater than λ / 32, or λ / 28, or λ / 24, or λ / 20, or λ / 16. λ is the mean wavelength of the Nutzbands, or the useful bands of the RF filter. From the same ^¬ surface is preferably connected to its short side, that is its width with the line section of the Umgehungslei ^¬ processing. Such dimensioning ensures that any resonances are reliably shifted out of the useful band of the RF filter.

Another embodiment of this invention be ^¬ writes that the m bypass lines separates complete charge from each run and only meet at the common-connection contact. This allows very high currents from the individual signal line connection contacts to the common

Connection contact to be transferred. Alternatively, it is possible that two or more of the m bypass ^¬ lines have a common portion, wherein the portion is connected to the common-Anschlußkontaktierung. In an additional embodiment of the invention, at least one point of interruption is formed within at least one of the m bypass lines, which divides the at least one of the m bypass lines into two galvanically separated line segments. The point of interruption is then bridged or bridged by a Lötverbin ^¬ dung. This allows a universal circuit board to be made, bridging the corresponding breakpoints depending on which devices are connected to the Common port. If, for example, a DC voltage and a low-frequency pilot signal are to be transmitted from the first signal line connection to the common connection, then the interruption point in bypassed the first bypass line. Not automatically a DC voltage flows in the direction of the second signal line terminal, because the second Un ^¬ terbrechungsstelle was not bridged. In addition, no RF signal, although highly filtered by the low-pass filter, can propagate toward the second signal line terminal. Standard ^¬ default all break points are not bridged. These are only connected as needed.

In another embodiment, the RF filter still has a housing cover that covers the printed circuit board via ^¬ and is electrically conductively connected with the peripheral housing wall. This ensures that external weather influences, such as moisture, do not change the electrical properties of the HF filter over time.

Finally, in another embodiment of the invention, the printed circuit board consists solely of FR4 with exactly two layers. The bypass lines consist, as optionally, of the ground surfaces of a copper layer with a layer thickness of> 18 ym or with ^ 35 ym. It is also possible to use thick copper layers with a layer thickness of> 70 μm. This ensures that can be transmitted from ^¬ sufficiently high currents and the entire arrangement also meets the requirements with respect to the lightning protection system. Various embodiments of the invention are described below with reference to the drawings in ^¬ way of example. The same items the same reference numerals. The corresponding figures of the drawings show in detail:

Figure 1A: a two-dimensional plan view of a

 RF filter whose housing cover and its existing of a printed circuit board cover are removed;

Figure 1B: a spatial representation of the open

 RF filter of Figure 1A;

Figure IC shows another three-dimensional representation of the ge ^¬ opened RF filter of Figure 1A; Figure 2: a part of a longitudinal section through a

Signal line connection, which is galvanically connected to the Lei ^¬ terplatte;

3A shows a top of the circuit board having a plurality of bypass lines provide interrupt with ^¬, wherein a plurality of compensation areas are directly electrically connected to the bypass lines ^¬; Figure 3B: an underside of the circuit board, the next

 Having openings for screw a continuous ground surface; and

FIGS. 4A to 4D:

various embodiments show the possi ^¬ possibilities, as the compensation surface can be formed and connected to the bypass ^¬ line. FIG. 1A shows a plan view of a cavity-type RF filter 1 with a removed housing cover 15 and a removed cover 2 which, as will be explained below, is a printed circuit board 2. The RF filter 1 has a housing 3, the ei ^¬ nen housing bottom 4, the cover 2 spaced from the housing bottom 4 and a housing wall 4 and the cover 2 circumferential housing wall 5 comprises.

I 2 auf. Der Common-Anschluss 6 ist mit einer Antenne, also einer gemeinsam genutzten Komponente, verbunden oder verbindbar. Die Signalleitungsanschlüsse

I 2 werden mit Ein^¬ heiten zur Signalverarbeitung und/oder Signalgenerierung verbunden. Bei dem ersten Signalleitungsanschluss

kann es sich beispielsweise um einen TX-Anschluss handeln, wobei es sich bei dem zweiten Signalleitungsanschluss I 2 um einen RX-Anschluss handeln kann. Die Erfindung ist natürlich nicht nur auf einen Common-Anschluss 6 und zwei Signalleitungsanschlüsse

I 2 beschränkt. Es kön- nen auch mehr als ein Common-Anschluss 6 und weniger oder mehr als zwei Signalleitungsanschlüsse

I 2 einge^¬ setzt werden. Vorzugsweise weist die Erfindung m Signal^¬ leitungsanschlüsse I 2 , 7_m auf, mit m > 1, Vorzugs- weise mit m > 2. Für eine bessere Übersicht sind in den Zeichnungsfiguren allerdings nur ein Common-Anschluss 6 und zwei Signalleitungsanschlüsse

I 2 dargestellt. Das HF-Filter 1 arbeitet als Bandpass, Dualband-, Trip- pel-Band, oder Multi-Band-Combiner . At an RF filter 1, a filter is in the context of this invention understood, which has at least a first terminal and at least a second terminal ^¬, wherein an RF signal supplied to the first and / or second terminal and filtered at the second and / or first connection is output again. In the present case, the RF filter 1 is a duplexer. The duplexer has a common terminal 6 and two signal line terminals

I 2 on. The common connection 6 is connected or connectable to an antenna, that is to say a shared component. The signal line connections

I 2 are connected to a ^¬ units for signal processing and / or signal generation. At the first signal line connection

For example, it may be a TX connection, wherein the second signal line connection I 2 may be an RX connection. Of course, the invention is not limited to a common terminal 6 and two signal line terminals

I 2 limited. There may also be more than one common port 6 and fewer or more than two signal line ports

I 2 be ^¬ sets. Preferably, the invention m ^¬ signal line terminals I 2, 7 _m, with m> 1, preferential with m> 2. For a better overview, however, only one common connection 6 and two signal line connections are shown in the drawing figures

I 2 shown. The RF filter 1 operates as a bandpass, dual band, triple band, or multi-band combiner.

The at least one common terminal 6 is connected to the m Sig ^¬ nalleitungsanschlüssen Ii, I 2, 7 _m m filter paths 81, 82, 8 _m. The m filter paths 81, 82, 8 _m are preferably separated from each other. This means that an electromagnetic coupling between at ^¬ different handy filter paths 81, 82, 8 _m is not present or negligible. Each filter path 81, 82, 8 _m comprises this case at least one, preferably more Re ^¬ sonatorkammern 9i_i, 9i_2, ... 9i_ _n; 9 ₂ _i, 9 ₂ _2, ... 9 ₂ _ _n ; 9 _m _i,

9m 2 r ··· n · In each resonator chamber 9i 1, 9i 2, ■■■ 9i _n ; 9 ₂ _i, 9 ₂ _2, - 9 ₂ _ _n ; 9 _m _i, 9 _m _ ₂ , - 9 _m _ _n is formed from a resonator ^¬ . Are there several resonator chambers 9i 1, 9i 2, 9i_ _n ; 9 ₂ _i, 9 ₂ _2, - 9 ₂ _ _n ; 9 _m _i, 9 _m _ ₂ , ... 9 _m _ _n in a filter ^¬ path 81, 82, 8 _m , then the different Resonato ^¬ ren ren a filter path 81, 82, 8 _{m are} electromagnetically coupled together. Each of the m filter paths 81, 82, 8 _m comprises at least one, preferably at least two resonators which are coupled together. Within each of the resonator chambers 9i 1, 9i 2, ■■■ 9i _n ; 2 1, ^ 2 2, ■■■ 2 _n ; 9 _m 1, 9 _m 2 _t ... 9 _mn there is at least one resonator ^¬ inner conductor 10. On the m filter paths 81, 82, 8 _m , however, no DC components or low-frequency signals can be transmitted. Each of the m filter paths 81, 82, 8 _m can be designed as a resonator or low-pass with DC stop or band pass or high pass or HF line with DC stop. The wording "DC-Stop" indicates only that no DC or niederfre ^¬-frequency signals can be transmitted.

The common terminal 6 is coupled via a first opening in the housing 3 to one end of the at least m filter paths 8i, 82, 8 _m and the m Signalleitungsanschlüs ^¬ sen Ii, I2, 7 _m are each a further opening in

Der Common-Anschluss 6 ist galvanisch noch mit einem Tiefpassfilter 11 verbunden oder verbindbar. Das gleiche gilt auch für die m Signalleitungsanschlüsse 1_\, I2, 7_m, die ebenfalls mit Tiefpassfiltern 11 verbunden oder verbindbar sind. Bei dem Tiefpassfilter 11 handelt es sich vorzugsweise um ein LC-Filter. Weder der Common- Anschluss 6, noch jeder der m SignalleitungsanschlüsseHousing 3, each with one of the opposite m ends of the m filter paths 8 ₁ , 82, 8 _m coupled. In the coupling, it is preferably a capacitive coupling toward the resonator inner conductor 10 of the respective resonator chamber 9i_i, 9i_ _2, ... _n 9i_; 9 ₂ _i, 9 ₂ _2, ... 9 ₂ _ _n ;

The common terminal 6 is galvanically connected to a low-pass filter 11 or connectable. The same applies to the m signal line connections 1 _\ , I2, 7 _m , which are also connected or connectable to low-pass filters 11. The low-pass filter 11 is preferably an LC filter. Neither the common terminal 6, nor each of the m signal line connections

But 1 _1, I 2, 7 _m must necessarily be connected to a Tiefpassfil ^¬ ter. 11 In the event that no DC voltage or no low-frequency signal in the direction of the common terminal 6 is to be transmitted from one of the m signal line connections 1 _\ , I2, 7 _{m, it} does not have to be galvanically connected to a low-pass filter 11 either. Via the low-pass filter 11, a galvanic connection between each of the m signal line connections 1 _\ ,

12, 7 _m and the common terminal 6 for transmitting egg ^¬ ner DC voltage or a low-frequency signal, such as pilot tones, in particular egg ^¬ ner frequency of 2.176 MHz (AISG signal; engl Antenna Interface Standard Group;.. dt standardization group for the antenna interface), take place. The DC voltage or the low-frequency signals are, as will be explained below, at the beginning of the filter ^¬ paths 8i, 82, 8 _m discharged from these and at the end of the filter paths 8 ₁ , 82, 8 _m again eingelei ^¬ tet, so fed.

The common terminal 6 could be inductively coupled with the m filter paths 8 ₁ , 82, 8 _m instead of capacitively.

Ί 2 , 7_m. The same also applies to the m Signalleitungsan ^¬ connections

Ί 2, 7 _m .

FIG. 1B shows a spatial representation of the opened RF filter 1 from FIG. 1A. The resonator inner conductors 10 have a receiving opening for receiving a Abstimmelements. The resonator inner conductors 10 extend from the housing bottom 4 in the direction of the housing cover 15, as shown in FIG. But we touch ^¬ of the housing cover 15 nor the printed circuit board 2. The paths 8 m filter _1, 82, 8 _m are at least partially separated from each other by at least one partition wall sixteenth As will be explained later, the printed circuit board 2 with a front side of the partition wall 16 and / or with an end face of the peripheral housing wall 5 can be screwed or screwed. Figure IC shows another three-dimensional representation of the ge ^¬ opened RF filter 1 of Figure 1A. The perspective from which the RF filter 1 is shown corresponds to that of FIG. 1B. However, objects or parts of ob- indicated projects that are obscured by other with gestrichel ^¬ th lines and, therefore, visible.

Figure 2 shows a longitudinal section through the RF filter 1 in the range in which the circuit Signalleitungsan- 1 _\ located. The receiving opening of the resonator inner conductor 10 is accessible from outside the housing 3, in this case via the housing bottom 4. A tuning element can therefore be screwed from outside the housing 3. A capacitive coupling-off ^¬ or coupling plate 17 _m is electrically connected to the circuit Signalleitungsan- 1 _\, 7 _2, 7 and of the resonator

Inner conductor 10 is arranged at a distance. The housing 3 is closed by means of the printed circuit board 2 and the Ge ^¬ housing cover 15. The housing cover 15 while the circuit board 2 covers over ^¬ but without the surrounding ^¬ hung lines 20i, 2R _2, 20 _m, which will be described below, contact. The housing cover 15 is preferably located only on the housing wall 5. But it can also be additionally supported on a border of the circuit board 2, wherein this area is free of the bypass lines 20i, 2O ₂ , 20 _m . On a first side 2i of the printed circuit board 2, the order ^¬ hungsleitungen 20i, 2O ₂ , 20 _m are arranged. In this first page 2i is a top surface 2i of the circuit board 2. The top surface 2i is disposed in this exporting ^¬ approximately example closer to the housing cover 15 as a second side 2 ₂ of the circuit board 2. The second side 2 ₂ of the circuit board 2 is also referred to as the bottom 2 ₂ . The second side 2 _{2 of} the printed circuit board 2 points in the direction of the m filter paths 8 ₁ , 8 ₂ , 8 _m and ver closes the housing 3 with the filter paths 8 i, 8 ₂ , 8 _m therein.

A coil of the low-pass filter 11 is electrically connected with egg nem inner conductor intermediate piece 18 of the signal line terminal 1 _\. About this takes place the extraction or coupling of the DC voltage or the low-frequency signal. The low pass filter 11 connects the pipe connection Signallei- 1 _\ with the Signalleitungsanschlusskontak- orientation 19i on the circuit board 2, with which in turn the bypass line 20i is electrically connected.

In principle, the printed circuit board 2 m Signalleitungsanschlusskontaktierungen 19i, 1 9 _2, having 19 _m, each of said m Signalleitungsanschlusskontaktierungen 19i, 1 9 _2, 19 _m with one of the m Signalleitungsanschlüs ^¬ sen 7 i, 7 _2, 7 _m galvanically is connectable or connected. This galvanic connection is preferential ^¬ over the low-pass filters 11. However, it could also be done via a cable or metal wire. This is al ^¬ lerdings only if a low-pass is formed in the common connection. 6

The same also applies to the common terminal 6. The printed circuit board 2 has a common terminal contact 23, which is galvanically connected to the common terminal 6. This galvanic connection is preferably via the low-pass filters 11. However, it could also be done via a cable or metal wire. However, this is only possible if a low-pass filter is formed at the signal line terminals 7 i, 7 ₂ , 7 _m . The common

Terminal contact 23 is the point on the circuit board 2 to which the cable connected to the common terminal 6 is connected, is applied. This cable can also be connected to the low pass 11. The same applies to the m Signalleitungsanschlusskontaktierungen

verfügt außerdem noch über eine Steckverbindung 24 über die das Innenleiterzwi- schenstück 18 mit einem nicht dargestellten Kabel, vorzugsweise einem Koaxialkabel, verbunden werden kann. Die Steckverbindung 24 weist eine Innenleiterbuchse 25 auf, die ein Innenleiteraufnahmeelement umfasst. Die Innen^¬ leiterbuchse 25 ist galvanisch mit dem Innenleiterzwi- schenstück 18 und damit mit dem Tiefpass 11 verbunden. Weiterhin umfasst die Steckverbindung 24 eine Außenlei- terbuchse 26, die galvanisch mit dem Gehäuse 3 verbunden ist. Dichtungen stellen sicher, dass keine Feuchtigkeit in das HF-Filter 1 eindringen kann. The signal line connection

also has a connector 24 via which the Innenleiterzwi- unit piece 18 with a cable, not shown, preferably a coaxial cable, can be connected. The connector 24 has an inner conductor socket 25, which comprises an inner conductor receiving element. The inner ^¬ conductor socket 25 is galvanically connected to the Innenleiterzwi- schenstück 18 and thus to the low-pass filter 11. Furthermore, the plug connection 24 comprises an outer conductor bush 26, which is galvanically connected to the housing 3. Seals ensure that no moisture can penetrate into the RF filter 1.

Figure 3A shows the first side 2i of the circuit board 2 having a plurality of bypass lines 20i, 20 _2, which are separated by vonei ^¬ Nander interruption points 30th With the bypass lines 20i, 2O _{2 a} plurality of compensation ^¬ surfaces 31 are electrically connected. Via the Signalleitungsanschlusskontaktierungen 19i, 19 ₂ , 19 _m and the common terminal contact 23, the galvanic contacting with the m signal line ^¬ connections Ii, I2, .. ·, 7 _m and the common port 6. So ^¬ probably the first bypass line 20i , as well as the second bypass line 2O ₂ have at least one Leitungsab ^{¬ section} 33, which is galvanically connected to at least one equalization surfaces 31 ^¬ . The at least one from ^¬ equal surface 31 constitutes an additional capacitance, which is formed by the fact that on the back of the circuit board 2, ie on the second side 2 _{2 of} the conductor ^¬ plate 2 at least below the compensation surface 31 ei ^¬ ne metal surface is formed, which is galvanically connected to the mass of the circumferential housing wall 5 and acts as a ground plane.

The compensation area 31 may also be formed by a Spread ^¬ tion of the bypass lines 20i, 2O _2, 20 _m, which is formed on the at least one line section 33rd The broadening can occur on one side or on both sides of the line section 33. In the latter case, the conduit section 33 preferably runs in the middle of the operations. The operations are all arranged on the first side 2i of the printed circuit board 2.

The at least one compensation surface 31 is generally arranged between the common connection contact 23 and the m signal line connection contacts 19i, 19 ₂ , 19 _m .

The compensation surface 31 has in this Ausführungsbei ^¬ game in plan view essentially the shape of a rectangle. However, it may also substantially have the shape of a square, or oval or circle, or a regular or irregular n-polygon, or approximate it. It is also possible that only a part of the compensation surface 31 has such a shape, wherein another part of the Ausgleichsflä ^¬ che 31 has a different shape. Within FIG. 3A, the common terminal contact 23 is less than 1 cm away from the equalization surface 31. However, it would equally be possible for the gap to be larger and the common terminal contact 23 away from the balance surface 31 less than 10 cm, or less than 8 cm, or less than 6 cm, or less than 5 cm, or less than 4 cm is. The same also applies to the distance of the m signal line connection contacts 19i, 19 ₂ , 19 _m to the respective compensation surface 31.

The size of the individual compensation surfaces 31 can vary with each other. They can all be the same size or different sizes. It may also be that some compensation surfaces 31 are the same size, but in turn differ from other compensation surfaces 31 in size. The compensation surfaces 31 can also be. With respect to their distance to the respective Anschlusskontaktierung 19i, 19 ₂ , 19 _m ; 23 may be arranged differently far away and also have completely or partially unterschiedli ^¬ che forms.

The compensation area 31 may have a surface area aufwei ^¬ sen, which is greater than λ ^2/8192, or λ ^2/4096, or λ ^2/2048, or λ ^2/1024, or λ ^2/512, or λ ^2/256, or λ ^2/128, or λ ^2/64 or λ ^2/32 or λ ^2/16. It would also be possible that all compensation areas 31 have a total of a surface area which is greater than λ ^2/8192, or λ ^2/4096, or λ ^2/2048, or λ ^2/1024, or λ ^2/512, or λ ^2/256, or λ ^2/128, or λ ^2/64 or λ ^2/32 or λ ^2/16, wherein λ is the mean wavelength of the useful band, or the working bands of the RF filter. 1 The compensation surface 31 is usually a planar structure.

Furthermore, not at each connection contact 19i, 192, ···, 19 _m ; 23 may be arranged a compensating surface 31. It is therefore possible that there are fewer compensation surfaces 31 than connection contacts 19i, 19 ₂ , ···, 19 _m ; 23. However, there may also be more compensation surfaces 31 than connection contacts 19i, 19 ₂ , ···, 19 _m ; 23, or, as shown in Figure 3A, as many compensation surfaces 31 as terminal contacts 19i, 19 ₂ , ···, 19 _m ; 23rd

Preferably, the compensation surfaces 31 are directly electrically connected to the at least one line section 33 of one of the m bypass lines 20i, 2 O 2, 20 _m .

A "direct" connection is meant that the line section 33 of the respective bypass ^¬ line 20i, 2 O 2, 20 _m same part of the same surface is from ^¬ 31st This means that the compensatory surface 31 with the at least one Leitungsab ^¬ section 33 of the bypass lines 20i m, 2 O 2, 20 _m facing ^¬ least a common connection portion 35 ^¬. This common connection section 35 is shown in FIGS. 4A, 4B and 4D. The at least one common connection section 35 preferably has a length which is greater than the average width of the bypass line 20i, 2 O 2, 20 _m . The at least one common connecting portion 35 may also have a length that is greater than 70%, or 80% or 90% of the mean width of the bypass 20i, 2 O 2, 20 _m . Within FIG. 4C, as will be explained later, an indirect connection between the circumvention and the compensation surface 31

The at least one compensation area 31 is provided with an IH rer pages directly linked to the at least one line portion 33 of the bypass line 20i, 2 O 2, 20 _m ver ^¬ connected, wherein the at least one side preferably kür ^¬ zer, as at least one other side of the Compensation surface ^¬ 31. In the event that the compensation surface 31 has the shape of a rectangle, the contacting with the bypass line 20i, 2 O 2, 20 _m preference ^¬ on one of the shorter sides or on the shortest side of the rectangle instead of. Preferably, at least one corner of at least one compensating surface 31 is rounded. It may also be that at least one corner of all equalization surfaces 31 is rounded. Within FIG. 3A it is shown that all corners of all the compensation surface 31 are rounded off. This could of course only in an off ^¬ same area 31 be the case.

Within FIG. 3A, two bypass lines 20i, 2 O 2 have a common section 40, the section 40 being connected to the common connection contact 23. Of course, this situation may apply to more than two bypass lines 20i, 2 O 2, 20 _m . It is also possible that at least two, preferably all Conversely ^¬ hung lines 20i, 2 O 2, 20 _m completely separated from each other and extend only on the common-connection contact 23 meet. A combination is also possible. Thus, on the one hand, there may be bypass lines 20i, 2 O 2, 20 _m , the most complete dig separated from each other and on the other hand sol ^¬ che ^having a common portion 40. All this is possible on a common circuit board 2. The bypass lines 20i, 2O _2, 20 _m and, optionally, the joint portion 40 extend predominantly, preferably ^¬, exclusively on one side of the circuit board 2, here on the first side 2i of the circuit board. 2

I 2 , 7_m hin zu dem Common-Anschluss 6 übertragen werden soll. Die Lötbrücke kann dabei sehr einfach und reproduzierbar eingesetzt werden. Figure 3A also shows that within at least one of the bypass lines 20i m, 2O _2, 20 _m and / or intra ^¬ half of the common section 40 at least one sub ^¬ refraction point is formed 30th The interrupt ^¬ point 30 divides at least one of m Umgehungslei ^¬ obligations 20i 2O _2, 20 _m or the joint portion 40 into two galvanically separated line segments. The line segments can be the same length, or, as shown in Figure 3A, have a different Län ^¬ ge. The break point 30 can be bridged by means of a solder connection. This has the advantage that only the printed circuit board 2 can be used for a plurality of RF filters 1, whereby the solder bridge can be set individually. This is done when a DC voltage and / or a low frequency signal from a signal line connection

I 2, 7 _m to the common port 6 is to be transmitted. The solder bridge can be used very easily and reproducibly.

The bypass lines 20i, 20 ₂ , 20 _m may be formed of a copper layer having a layer thickness of> 18 μιη or> 35 ym or> 70 ym. The Schichtdi ^¬ bridge is preferably, however, smaller than 200 .mu.m, and more preferably less than 150 ym. The part of the first Page 2i of the printed circuit board 2, which does not belong to the bypass ^¬ lines 20i, 2O ₂ , 20 _m is preferably provided with a continuous ground plane. The same applies to the second side 2 _{2 of} the conductor ^¬ plate 2. This is shown in Figure 3B. Vorzugswei ^¬ se this page includes a continuous ground plane with the exception of the openings which are required for attachment of the circuit board 2 to the housing 3 and with the exception of the openings through which the contacting of the connection contacts 19i, 19 _2, 19 _m; 23 with the

Low pass filters 11 takes place. The one or more low-pass filters 11 is / are arranged closer to the second side 2 _{2 of} the printed circuit board 2 than to the first side 2 ^{i of} the printed circuit board 2.

Figures 4A to 4D show different examples of execution ^¬ as the compensation area 31 is formed and may be connected to the bypass line 20i. The situation shown in these figures, of course, also applies to the other bypass lines 2O ₂ , 20 _m and the common portion 40. Within Figure 4A, the compensation surface 31 has the shape of a rectangle. From the same ^¬ surface 31 has a length which is greater than its width. The compensation surface 31 is connected with its width with the bypass line 20i. The width of the compensation surface 31 has a length that is greater than λ / 32, or λ / 28, or λ / 24, or λ / 20, or λ / 16. The longitudinal side has a length that is greater than λ / 16, or λ / 12, or λ / 8, or λ / 4, or λ, where λ is the mean wavelength of the useful band, or the useful bands of the RF filter. 1 is. The first bypass line 20i is at its Leitungsab ^{¬ section} 33 is electrically connected directly to the Ausgleichsflä ^¬ che 31. This connection takes place at a common connection section 35, which is shown in dashed lines.

Within FIG. 4B, the compensation surface 31 has a changed shape. One compensation surface 31 is cone-shaped and the other is circular. A compensation surface 31 is preferably already circular when a section forms a partial circle.

In Figures 4A and 4B is a side IMP EXP ^¬ together, so over its entire length, line 20i with the bypass is electrically connected. Within Figure 4D is a side is connected galvanic ^¬ cally only over a part of its length with the bypass line 20i.

FIG. 4C shows an "indirect" connection of a compensation surface 31 with the bypass line 20i. From the same ^¬ surface 31 is connected via an intermediate line 45 to the bypass line 20i. The width of the intermediate line 45 is smaller than the side of the compensation surface 31, which contacts the intermediate line 45. The width of the intermediate line 45 is also smaller than the width of the bypass line 20i. However, it can be just as big. It can still be said that the bypass 20i is increased in width. The magnification includes in this case, in addition to the compensation surface 31 nor the Zwischenlei ^¬ tion 45th The low-pass filter 11 is preferably arranged closer to the second side 2 _{2 of} the printed circuit board 2 than on the first side 2i of the printed circuit board 2. The low-pass filter 11 is at least partially or completely constructed with discrete components and not formed by planar Struktu ^¬ ren on the circuit board 2 , A discrete construction ^¬ element is an electronic component, which is accommodated in a housing ei ^¬ genes. The low-pass filter 11 is preferably not part of the printed circuit board 11, or is spatially spaced therefrom.

Preferably, the bypass line has a width that is less than 5 cm, or 4 cm, or 3 cm, or 2 cm, but greater than 4 mm or greater than 6 mm or greater than 8 mm.

The invention is not limited to the described embodiments. In the context of the invention, all described and / or drawn features can be combined with one another as desired.

Claims

Claims 1. RF filter (1) having the following features:  - A housing (3) comprising a housing bottom (4), one of the housing bottom (4) spaced cover (2) and between the housing bottom (4) and the cover (2) encircling housing wall (5); - At least one common terminal (6) and m Signallei ^¬ tungsanschlüssen {Ii, 7 ₂ , 7 _m ), with m> 1, preferably ^¬ m> 2, wherein the common terminal (6) with the m signal line terminals {Ii , I2, 7 _m ) is connected via m filter paths (81, 82, 8 _m ); - The common terminal (6) is coupled via a first opening in the housing (3) with one end of at least m Fil ^¬ ter paths (81, 82, 8 _m ) and the m Signallei ^¬ tion terminals {Ii, 7 ₂ , 7 _m) are coupled via a respective white ^¬ tere opening in the housing (3) with one of the counter opposite ends of the m m filter paths (81, 82, 8 _m);  - The cover (2) is a circuit board; - The circuit board (2) has a common terminal contact (23) which is galvanically connected to the common terminal (6); the printed circuit board (2) has m signal line terminal contacts (19i, 1 92, ··, 19 _m ), each of the m signal line terminal contacts (19i, 1 92, ···, 19 _m ) being connected to one of the m signal line terminals { II, I2, 7 _m ) is galvanically connected; - Between the common terminal (6) and the common terminal contact (23) at least one low-pass filter (11) is arranged and / or between at least one, preferably all of the m signal line connections {Ii, 7 ₂ , 7 _m ) and the corresponding signal - line connection contact (19i, 1 92, ···, 19 _m ) is arranged in each case at least one low-pass filter (11); - The printed circuit board (2) comprises m bypass lines (20i, 2O ₂ , 20 _m ), via which the common connection contact (23) galvanically connected to the m Sigalleitungsanschlusskontaktierungen (19i, 1 92, ···, 19 _m ) or is connectable; - at least one of m bypass lines (20i, 2O _2, 20 _m) has at least one line section (33) which is electrically connected to at least one compensation area (31), wherein the at least one selected from ^¬ same surface (31) an additional capacitance is ^¬ represents, whereby resonances within the circuit board (2) are shifted in their frequency and / or attenuated that they no longer fall into the useful band of the RF filter (1). 2. HF filter according to claim 1, characterized by the following feature: - each of m filter paths (8 _1, 82, 8 _m) comprises at least ^¬: A resonator; and or At least one RF line; and or  • a low pass or a high pass or a band pass,  wherein these elements are designed such that no DC components and / or low-frequency Signals can be transmitted. 3. RF filter according to claim 1 or 2, characterized by the following features: - the common terminal is coupled kapa ^¬ zitiv or inductively with the m filter paths; and or - the m signal line terminals are coupled capacitively or inductively coupled to the m filter ^¬ paths. 4. HF filter according to one of the preceding claims, characterized by the following features: - The m bypass lines (20i, 2O ₂ , 20 _m ) are all ^¬ on a first side (2i) of the printed circuit board (2) arranged; - A second side (2 ₂ ) of the printed circuit board (2), which is the first side (2i) of the printed circuit board (2) opposite, at least at the location which lies below the at least one compensating surface (31), a ground surface which is galvanically connected to the circumferential housing wall (5); or the second side (2 ₂ ) of the printed circuit board (2) facing the first side (2i) of the printed circuit board (2) is predominantly, preferably completely covered by a ground surface, which is galvanically connected to the surrounding housing wall (5) is. 5. RF filter according to claim 4, characterized by the following feature: - The second side (2 ₂ ) of the circuit board (2) points in the direction of the m filter paths (8 ₁ , 8 ₂ , 8 _m ) and closes the housing (3) with the therein Filter paths (8 ₁ , 8 ₂ , 8 _m ). 6. RF filter according to claim 4 or 5, characterized by the following features: - The compensation surface (31) is formed as a planar structure on the first side (2i) of the printed circuit board (2) by a metal layer of the printed circuit board (2). 7. HF filter according to one of the preceding claims, characterized by the following features: - At least one of the m bypass lines (20i, 2O ₂ , 20 _m ) has at its at least one line section (33) to a broadening, whereby the compensation ^¬ surface (31) is formed. 8. RF filter according to claim 7, characterized by the following features:  - The broadening is formed on one side or on both sides of the line section (33). 9. HF filter according to one of the preceding claims, characterized by the following features: the compensation surface (31) or at least a part of the compensation surface (31) has the shape in plan view - a square; or  - a rectangle; or an n-corner with n>2; or - an oval; or  - a circle; or  - a regular or irregular n-polygon or approximates it. 10. HF filter according to one of the preceding claims, characterized by the following features: - From the common terminal contact (23) the compensating surface (31) is less than 10 cm, preferably we ^¬ niger than 8 cm, more preferably less than 6 cm, more preferably less than 5 cm, more preferably less than 4 cm away; and or from each of the m signal line terminal contacts (19i, 192, 19 _m ), the compensation area is less than 10 cm, preferably less than 8 cm, more preferably less than 6 cm, more preferably less than 5 cm, further preferably less than 4 cm. 11. HF filter according to one of the preceding claims, characterized by the following feature: - The compensation surface (31) is directly or indirectly ^¬ bar with the at least one line section (33) ei ^¬ ner of m bypass lines (20i, 2Ü ₂ , 20 _m ) galva ^¬ nically connected. 12. HF filter according to claim 11, characterized by the following features: - the compensating surface (31) has the at least ei ^¬ NEN line section (33) of the bypass lines m (20i, 2O _2, 20 _m) at least one common Verbin ^¬-making portion (35); - The at least one common connecting portion (35) has a length which is greater than the average width of the bypass line (20i, 2O ₂ , 20 _m ); or  the at least one common connection section (35) has a length which is greater than 70%, 80% or 90% of the mean width of the bypass ^¬ line (20i, 2O ₂ , 20 _m ). 13. RF filter according to claim 11 or 12, characterized by the following feature: - The at least one compensating surface (31) is connected at one of its sides directly to the at least one line section (33), wherein the at least one side is shorter or longer or is equal to or at least one further side of the off ^¬ same surface (31). 14. HF filter according to one of the preceding claims, characterized by the following features:  - At least one corner of at least one compensating surface (31) is rounded off; or  - At least one corner of each compensating surfaces (31) is rounded off; or - All corners of at least one compensating surfaces (31) are rounded; or  - All corners of all compensating surfaces (31) are rounded. 15. HF filter according to one of the preceding claims, characterized by the following feature: - The balancing surface (31) has a length which is greater than:  λ / 16, or  λ / 12, or  λ / 8, or  λ / 4, or  λ, or;  and a width greater than:  λ / 32, or  λ / 28, or  λ / 24, or  λ / 20, or  λ / 16, or;  where λ is the mean wavelength of the useful band, or the useful bands of the RF filter (1). 16. HF filter according to one of the preceding claims, characterized by the following feature:  - The balancing surface (31) has an area greater than: λ ^2/8192, or λ ^2/4096, or λ ^2/2048, or λ ^2/1024, or λ ^2/512, or λ ^2/256, or λ ^2/128, or λ ^2/64, or λ ^2/32, or λ ^2/16, or - All compensation surfaces (31) have in total an area greater than: λ ^2/8192, or λ ^2/4096, or λ ^2/2048, or λ ^2/1024, or λ ^2/512, or λ ^2/256, or λ ^2/128, or λ ^2/64, or λ ^2/32, or λ ^2/16, where λ is the mean wavelength of the useful band, or the useful bands of the RF filter (1). 17. HF filter according to one of the preceding claims, characterized by the following features: at least two of the m bypasses (20i, 2O ₂ , 20 _m ) are completely separated from each other and meet only at the common terminal contact (23); and or two or more of the m bypasses (20i, 2O ₂ , 20 _m ) have a common portion (40), wherein the portion (40) is connected to the common terminal contact (23). 18. HF filter according to one of the preceding claims, characterized by the following features: - Within at least one of the m bypass lines (20i, 2O ₂ , 20 _m ) is at least one break ^{¬ point} (30) is formed, which subdivides at least one of the m ummungsungsleitungen (20i, 2O ₂ , 20 _m ) into two electrically isolated line segments ; - The point of interruption (30) can be bridged or bridged by means of a solder ^¬ connection. 19. HF filter according to one of the preceding claims, characterized by the following feature: - The RF filter (1) has a housing cover (15) which covers the printed circuit board (2) and is electrically conductively connected to the umlau ^¬ fenden housing wall (5). 20. HF filter according to one of the preceding claims, characterized by the following features: - the m filter paths (8i, 82, 8 _m) are at least section-wise from ^¬ by partition walls (16) ge ^¬ from each other; - The circuit board (2) is screwed or screwed to an end face of the partitions (16) and / or an end face of the umlau ^¬ fenden housing wall (5). 21. HF filter according to one of the preceding claims, characterized by the following features:  - The circuit board (2) is double-layered; and or  - The circuit board (2) consists of FR4; and or - The bypass lines (20i, 2O ₂ , 20 _m ) consist of a copper layer with a layer thickness of> 18 ym or with ^ 35 ym or with ^ 70 ym.