Abstract
An RF component can have a reduced electromagnetic internal coupling and may be suitable for miniaturization as a result. The component includes a micro acoustic filter of ladder-type design in a housing and a double coil having a first coil segment and a second coil segment. The two coil segments are oriented in opposite directions. The two coil segments are arranged without crossover in one layer and the double coil is arranged in proximity to a parallel branch resonator of the ladder-type filter structure.
Claims
1. An electrical RF component comprising: a housing; a micro acoustic filter having a ladder-type filter structure having a series branch resonator and a parallel branch resonator in the housing; and a double coil having a first coil segment and a second coil segment in the housing, wherein the first coil segment has an external turn segment having a first orientation and the second coil segment has an external turn segment having a second orientation in the opposite direction, wherein the external turn segments of the first and second coil segments are connected at a contact point, wherein the first and second coil segments are arranged without crossover and in a single layer, and wherein the double coil is arranged in proximity with the parallel branch resonator.
2. The electrical RF component according to claim 1, wherein the first coil segment is embodied in a spiral fashion.
3. The electrical RF component according to claim 2, wherein the second coil segment is embodied in a spiral fashion.
4. The electrical RF component according to claim 1, wherein the first coil segment is constructed with an m-gonal basic contour, and wherein m>=3.
5. The electrical RF component according to claim 1, wherein the first coil segment is constructed from n rectilinear conductor sections, and wherein n>=3.
6. The electrical RF component according to claim 1, wherein the first coil segment has an aspect ratio of less than 1.
7. The electrical RF component according to claim 1, wherein the first coil segment has an aspect ratio substantially equal to 1.
8. The electrical RF component according to claim 1, wherein the first coil segment has an aspect ratio greater than 1.
9. The electrical RF component according to claim 1, wherein the first coil segment has a first extent and the second coil segment has a second extent that differs from the first extent.
10. The electrical RF component according to claim 1, wherein the first coil segment has a first extent and the second coil segment has a second extent that is substantially equal to the first extent.
11. The electrical RF component according to claim 1, wherein the first coil segment has a first number of turns and the second coil segment has a second number of turns that is different than the first number of turns.
12. The electrical RF component according to claim 1, wherein the first coil segment has a number of turns and the second coil segment has the same number of turns.
13. The electrical RF component according to claim 1, wherein: the first coil segment has a center and the second coil segment has a center; a region of reduced electromagnetic coupling is determined by an axis that is perpendicular to a connecting line through both centers and runs through the contact point; and a component having a function sensitive toward inductive coupling is arranged in the region of reduced electromagnetic coupling.
14. The electrical RF component according to claim 13, wherein the region of reduced electromagnetic coupling comprises a double cone, and wherein the component function is arranged in a region of the double cone.
15. The electrical RF component according to claim 14, wherein the double cone has a half opening angle , and where <=50.
16. A method for producing an electrical RF component according to claim 1, wherein both coil segments are formed in a common layer.
17. The method according to the claim 16, wherein the common layer is formed by deposition of 2 or more plies.
18. An electrical RF component comprising: a housing; a micro acoustic filter having a ladder-type filter structure having a series branch resonator and a parallel branch resonator in the housing; and a double coil having a first coil segment and a second coil segment in the housing, wherein the first coil segment has an external turn segment having a first orientation, wherein the second coil segment has an external turn segment having a second orientation in the opposite direction, wherein the external turn segments of the first and second coil segments are connected at a contact point, wherein the first and second coil segments are arranged without crossover and in a single layer, wherein the double coil is arranged in proximity to the parallel branch resonator, wherein the first coil segment has a center and the second coil segment has a center, wherein a region of reduced electromagnetic coupling is determined by an axis that is perpendicular to a connecting line through the centers of both the first and second coil segments and runs through the contact point, and wherein a component has a function sensitive toward inductive coupling is arranged in the region.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1) The RF component is explained in greater detail below on the basis of exemplary embodiments and associated schematic figures, in which:
(2) FIG. 1 shows a cross section through a housing H of the component C;
(3) FIG. 2 shows a possible arrangement of the double coil relative to a parallel resonator;
(4) FIG. 3 shows a component C, wherein the double coil has an aspect ratio of substantially 1;
(5) FIG. 4 shows a component C, wherein the double coil has an aspect ratio of greater than 1;
(6) FIG. 5 shows the region of the double cone relative to the orientation of the double coil;
(7) FIG. 6 shows one possible embodiment of the double coil;
(8) FIG. 7 shows an alternative embodiment of the double coil;
(9) FIG. 8 shows an alternative embodiment of the double coil;
(10) FIG. 9 shows an alternative embodiment of the double coil;
(11) FIG. 10 shows an alternative embodiment of the double coil;
(12) FIG. 11 shows an alternative embodiment of the double coil;
(13) FIG. 12 shows an alternative embodiment of the double coil;
(14) FIG. 13 shows a configuration of a coil segment having a pentagonal basic contour;
(15) FIG. 14 shows the matrix elements S.sub.12, S.sub.23 for duplexers with and without a double coil;
(16) FIG. 15 shows the TX-RX isolation of a duplexer, once with and once without a double coil;
(17) FIG. 16 shows the matrix parameters S.sub.12, S.sub.23 in a larger frequency range;
(18) FIG. 17 shows the matrix element S.sub.13 (TX-RX isolation) of a duplexer in a larger frequency range;
(19) FIG. 18 shows the reflection at the TX input;
(20) FIG. 19 shows the frequency-dependent input impedance at the TX input;
(21) FIG. 20 shows the reflection at the RX output;
(22) FIG. 21 shows the frequency-dependent impedance at the RX output;
(23) FIG. 22 shows the reflection at the antenna connection; and
(24) FIG. 23 shows the frequency-dependent impedance at the antenna connection.
DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS
(25) FIG. 1 shows a cross section through a component C. Component constituents CC are arranged in a housing H. The component constituents CC can be filter constituents operating with acoustic waves, for example. As a result of the continuous trend toward miniaturization, the distances between the component constituents CC are decreasing, with the coupling thus increasingly posing a problem. One of the constituents CC can now comprise a double coil, as described above, and thereby bring about a region of reduced coupling, such that a further miniaturization is possible.
(26) FIG. 2 shows one configuration of a component C comprising a ladder-type filter circuit. The ladder-type filter circuit comprises two series branch resonators interconnected in series. Furthermore, the filter circuit comprises two parallel resonators PR, which can in each case establish a connection of the series branch to ground. A double coil DCL is arranged in proximity to one parallel branch resonator PR and aligned such that the right hand one of the two series resonators SR is arranged in the region of a double cone. The double coil DCL in this case comprises a first coil segment S.sub.1 and a second coil segment S.sub.2. The two coil segments are oriented in opposite directions, based on the current flow direction.
(27) FIG. 3 shows a component C comprising a double coil DCL and a ladder-type filter structure. The ladder-type filter structure comprises five series branch resonators SR and four parallel branch resonators PR. The double coil DCL is arranged in proximity to the bottommost parallel resonator PR. A DMS structure DMS is arranged in a manner connected to the topmost series resonator SR. In this case, the double coil DCL is arranged and oriented relative to the DMS structure DMS such that the DMS structure DMS lies in a region of reduced coupling of the coil DCL. DMS structures can be interconnected in particular with an RX output of a duplexer and forward a received signal to a low noise amplifier. The coupling of undesired signals into a DMS structure would therefore be particularly critical.
(28) In this case, the double coil DCL has a length L.sub.1 and a width W.sub.1. In this case, the length is determined in the direction of a connecting line between the centers of the coil segments. The width is determined in a direction orthogonal thereto. Half of the length of the double coil, that is to say substantially the length of a coil segment, is used for defining the aspect ratio. The coil segments of the double coil in FIG. 3 substantially have an aspect ratio of 1.
(29) FIG. 4 shows one embodiment of the component C, wherein the coil segments of the double coil have an increased aspect ratio. The length L.sub.2 substantially corresponds to the length of the double coil in FIG. 3. The width W.sub.2 of the double coil in FIG. 4 is reduced compared with the width W.sub.1 of the double coil in FIG. 3. This results in an increased aspect ratio. Consequently, the overlap with the parallel resonator PR.sub.2 is reduced.
(30) FIG. 5 illustrates the alignment of the double cone relative to the alignment of the double coil. The coil segments in each case have an external turn segment EXTS, which are connected to one another at a contact point CP. The double cone DCN has an axis S of symmetry that is orthogonal to the connecting line of the centers of the coil segments. The double cone can have an opening angle of 240, that is to say a half opening angle of 40. The electromagnetic coupling, in particular the inductive coupling, is reduced in the region of the double cone. Components that are arranged in this double cone experience less inductive crosstalk resulting from current through the double coil.
(31) FIG. 6 shows one embodiment of the double coil, wherein the lower coil segment has a number of turns of 2.5 and the upper coil segment has a number of turns of 2.5.
(32) FIG. 7 shows one configurational form of the double coil, wherein the upper coil segment S.sub.1 has a number of turns of 2 and the lower coil segment S.sub.2 has a number of turns of substantially 0.75.
(33) FIG. 8 shows one configuration of the double coil, wherein the upper coil segment has a number of turns of 2.5 and the lower coil segment has a number of turns of 2.
(34) FIG. 9 shows one configuration of the double coil, wherein the upper coil segment S.sub.1 and the lower coil segment S.sub.2 have numbers of turns of in each case close to above 0.25. The double coil can be interconnected with further circuit constituents via an input and respectively output port P. In this regard, the double coil can be interconnected, e.g., with a parallel resonator of the ladder-type filter structure.
(35) FIG. 10 shows one embodiment, wherein the upper coil segment has a number of turns of 1.75 and the lower coil segment has a number of turns of 2.5.
(36) FIG. 11 shows one embodiment, wherein both the upper coil segment and the lower coil segment have a number of turns of 2.
(37) FIG. 12 shows one configuration of the double coil, wherein the upper coil segment has a number of turns of 2.125 and the lower coil segment has a number of turns of 2.625.
(38) FIG. 13 shows one configuration of a coil segment which has a pentagonal basic contour and comprises 15 rectilinear conductor segments. The innermost, shortest conductor segment in this case is aligned radially and does not contribute to the number of turns.
(39) In total, the number of turns of the coil segment in FIG. 13 is 2.8.
(40) It is possible for the m-gonal basic contour, here the pentagonal basic contour, to be based on a symmetrical m-gon. However, it is also possible for the basic contour to be based on an asymmetrical m-gon.
(41) FIG. 14 shows the magnitude of the matrix parameter S.sub.12 of the transfer function of a duplexer, once with a double coilcurve 1and once for a duplexer having a conventional single coilcurve 2. Curves 3 and 4 show the transfer function S.sub.23 of the reception filter. In this case, curve 1 of the duplexer having a double coil exhibits a significantly improved blocking effect outside the TX passband, in particular in the reception frequency range. The transfer functions 3 and 4 show substantially no influence of the double coil on the transfer function of the reception filter.
(42) FIG. 15 shows the TX-RX isolation (matrix parameter S.sub.13) with double coilcurve 1and without double coilcurve 2. In this case, the isolation is significantly better if the double coil is present.
(43) FIG. 16 shows the curves from FIG. 14, but in a further frequency range. It is possible to design the coil such that the transfer response far from the passband remains significantly unchanged.
(44) FIG. 17 shows the curves from FIG. 15 for a further frequency range.
(45) FIG. 18 shows the reflection (matrix element S.sub.ii) at the transmitting connection of a duplexer. In this case, curve 1 shows the reflection of a duplexer with a double coil, while curve 2 shows the reflection of a duplexer with a conventional single coil.
(46) FIG. 19 shows a Smith chart with the frequency-dependent impedance of the transmitting connection for two duplexers, of which one has a double coil and the other has a conventional single coil. In this case, the characteristic impedances do not differ significantly.
(47) FIG. 20 shows the reflection of the antenna connection (matrix element S.sub.33) for two duplexers, of which one has a double coil and the other has a conventional single coil. Both curve profiles are substantially identical, and so the double coil does not influence the reflection behavior at the antenna input.
(48) FIG. 21 shows the frequency-dependent impedance for the duplexers from FIG. 20, wherein likewise no change in the impedance as a result of a coil is discernible.
(49) FIG. 22 shows the reflection at the receiving connection for two duplexers, of which one comprises a double coil and the other comprises a conventional single coil. The curves lie substantially one above the other, and so the double coil has no discernible effect on the reflection at the receiving connection.
(50) FIG. 23 shows the frequency-dependent impedance at the receiving connection, once for a duplexer with a double coil and once for a duplexer with a single coil. No differences caused by the double coil are discernible at least in the relevant frequency range, i.e., in the range around 50, the center of the Smith chart.
(51) A component according to the invention is not restricted to any of the exemplary embodiments described here. Components comprising additional conductor sections, filters, impedance elements and combinations thereof likewise constitute exemplary embodiments according to the invention.
