DE102010011651B4 - Front-end circuit with increased flexibility in the arrangement of the circuit components - Google Patents

Abstract

Front-end circuit (FES), comprising
a first module (M1) having an antenna terminal (AAM1), a diplexer (DI) and a first duplexer (DU1),
a second module (M2) with a second duplexer (DU2),
- A first signal path (SP1) and a second signal path (SP2), wherein
the diplexer (DI) has an antenna connection, a low-pass filter with a low-pass connection and a high-pass filter with a high-pass connection,
the first duplexer (DU1) has a transceiver connection, a transmission connection and a reception connection,
the second duplexer (DU2) has a transceiver connection, a transmission connection and a reception connection,
the transmission reception connection of the first duplexer (DU1) via the first signal path (SP1) to the high-pass connection of the diplexer (DI) and the transmission-reception connection of the second duplexer (DU2) via the second signal path (SP2) to the lowpass Connection of the diplexer (DI) is connected,
further comprising
- Another bandpass filter having an input terminal and an output terminal, wherein
the input terminal of the further bandpass filter is connected to the high-pass connection,
the further band-pass filter works with surface acoustic waves, with guided bulk acoustic waves or with bulk acoustic waves, and
- The other bandpass filter lets satellite receive signals pass.

Description

The invention relates to front-end circuits, for. B. for mobile communication devices, with increased flexibility in the arrangement of the circuit components.

Front-end circuits interconnect in mobile communication devices one or more antennas with subsequent digital or analog circuit components.

Front-end circuits include signal lines in which RF signals z. B. propagate in the frequency range between 1 GHz and 2 GHz and at frequencies higher than 2 GHz, as well as active or passive filter components or switches. In particular front-end circuits, which have a plurality of frequency ranges, eg. As the 1 GHz frequency range and the 2 GHz frequency range cover, include circuit components, which are generally optimized specifically for the corresponding frequency range. The trend towards ever-increasing miniaturization means that more and more circuit components are integrated in a smaller and smaller number of modules.

From the publication US 2004/0224643 A1 is a front-end module with a diplexer, a first duplexer and a second duplexer known. The diplexer is connected to one terminal on an antenna and connected to other terminals with the first duplexer for separating W-CDMA transmit / receive signals and the second duplexer for separating N-CDMA transmit / receive signals.

The publication DE 20 2006 033 709 A1 relates to an electrical module with a duplexer connected to an antenna to separate a transmit and receive path.

The publication US 2007/02433833 A1 relates to a radio communication device having a duplexer connected to an antenna and further symmetrically connected to a receiving device and unbalanced to a S.endeeinrichtung.

The publication DE 10 2006 031 548 A1 relates to a transmitting / receiving circuit in which an antenna circuit is connected between an antenna and a duplexer, are attenuated by the antenna side received interference signals before they reach the duplexer a transmit and receive path.

In the publication DE 103 60 996 A1 is a handset that supports different frequency bands described, with duplexer, triplexer or quadplexer to separate the different frequency bands are connected via an antenna switch to an antenna.

The publication US 2005/0206478 A1 discloses a downsized and energy efficient antenna duplexer including a diplexer and first and second surface acoustic wave filters, and first and second phase shifter circuits.

From the publication US 7,126,440 B2 common-mode modules for front-end circuits are known which include both transmit and receive filters for both the CELL and PCS mobile radio systems.

Different duplexers are arranged together in a filter module behind an antenna.

It is an object of the present invention to provide a front end circuit having increased flexibility in the arrangement of the circuit components. In particular, it is an object of the present invention to provide a front-end circuit with improved routing of the signal path.

These objects are achieved by a front-end circuit according to claim 1. Further, dependent claims indicate design options.

The invention provides a front-end circuit comprising a first module having an antenna port, a diplexer and a first duplexer. The front-end circuit further includes a second module having a second duplexer. The front-end circuit also includes a first signal path and a second signal path.

A module in this case comprises a single electrical component in which at least one electrical function is integrated.

The diplexer has an antenna port, a low pass filter with a low pass filter port, and a high pass filter with a high pass filter port.

The first duplexer has a transceiver port, a transmit port, and a receive port. The second duplexer has a transceiver port, a transmit port, and a receive port. The transceiver port of the first duplexer is connected to the high pass port of the diplexer via the first signal path. The transceiver port of the second duplexer is connected to the low pass port of the diplexer via the second signal path.
The first module thus includes the diplexer and the first duplexer. The second duplexer is separated from the first module in the second module. The signal paths interconnect the duplexers with the diplexer. The fact that both duplexers are arranged in different modules, the developer of a front-end circuit receives a further degree of freedom in the spatial arrangement of the duplexer and in the layout of the waveforms of the signal paths.

The front-end circuit incorporates two duplexers, making it easy to cover transceiver operation in two different frequency ranges. The signal routing, d. H. the spatial arrangement of the signal paths, is particularly important in CDMA transmission systems of great importance. As a result of the compulsion to miniaturization essentially inevitably, diplexers and duplexers are preferably integrated into a single module.

The inventors have found, however, that only one of the duplexers, in particular its transmission signal path, can be optimally matched in terms of impedance to a power amplifier. In particular, the length of the line / signal path between the duplexer and the power amplifier is important. The impedance matching can be significantly degraded due to the phase shift caused by the length of the line. This effect weighs heavier the higher the frequencies of the RF signals and the longer the signal path. If a front-end circuit is optimized with respect to one duplexer, the other duplexer can only be adapted suboptimally.

The separation of the duplexers into different modules thus runs counter to the continuing trend of miniaturization, but allows an improved individual impedance matching of both duplexers. A resulting advantage in addition to the improved adaptation and the improved power consumption, because the signal transmission is less by poorly matched impedances, ie by reflection, deteriorated.

In one embodiment, the first duplexer or the second duplexer is designed for processing push-pull signals or for conversion between common-mode signals and push-pull signals. A corresponding duplexer thus has a balun functionality. Push-pull signals generally require a doubling of the signal paths and of the components connected in the signal paths, such as filters or amplifiers. In particular, the signal paths of receiving paths are designed as push-pull signal paths and connected to corresponding connections in the duplexer. Receive signal paths are connected to the output terminals of the duplexer. Thus, signal lines working with push-pull signals require an increased switching effort, but are less sensitive to common-mode noise.

In an embodiment, the first duplexer or the second duplexer comprises a surface acoustic wave filter. As a filter working with surface acoustic waves, a SAW filter (SAW = surface acoustic wave) or a GBAW filter (GBAW = Guided By Acoustic Wave = guided bulk acoustic wave) is suitable.

In an embodiment, the first duplexer or the second duplexer comprises a bulk acoustic wave or guided bulk acoustic wave filter. Working with acoustic waves filter, z. B. BAW (Bulk Acoustic Wave) filters, SAW or GBAW filters may have intrinsic balun functionality. By using such filters, additional balun circuits can be saved.

In one embodiment, one of the duplexers selected from the first duplexer and the second duplexer operates with surface acoustic waves or guided bulk acoustic waves, while the other duplexer operates with guided bulk acoustic waves or bulk acoustic waves. Such a so-called hybrid duplexer then works both with the help of surface acoustic waves and with the help of bulk acoustic waves. Bulk acoustic wave devices are generally more powerful than surface acoustic wave devices. For this purpose, components that work with surface acoustic waves offer developers of front-end circuits other, further optimization possibilities. The use of a hybrid duplexer thus enables the best filter technology to be used.

Due to the separation of the duplexer on different modules, it is possible in particular for the different duplexers different ways of working, eg. B. with bulk acoustic waves or with surface acoustic waves to choose.

It is possible to design the first module with a rectangular cross-section of size 3.0 * 2.5 mm ² and the second module with a rectangular cross-section of size 2.0 * 2.5 mm ² . The total footprint of both modules is therefore 12.5 mm ² . In a version of the front-end circuit optimized for miniaturization, a first module with a rectangular cross section of size 3.0 * 2.5 mm ² and the second module with a rectangular cross section of size 2.0 * 1.6 mm ² can be obtained ,

In one embodiment, one of the duplexers selected from the first duplexer and the second duplexer comprises a Coupled Resonator Filter (CRF) with balun functionality.

In one embodiment, the first duplexer comprises a bandpass filter with a passband in the 2 GHz frequency range and the second duplexer bandpass filter with a passband in the 1 GHz frequency range.

The first duplexer may include a first bandpass filter having a first passband and a second bandpass filter having a second passband.

The second duplexer may include a third bandpass filter having a third passband and a fourth bandpass filter having a fourth passband.

The following table gives possible values (in MHz) for the above four passbands: 1920 - 1980 2110 - 2170 1850 - 1910 1930 - 1990 1710-1785 1805 - 1880 1710 - 1755 2110-2155 824-849 869-894 830-840 875-885 2500 - 2570 2620 - 2690 880-915 925 - 960 1749.9 - 1784.9 1844.9 - 1879.9 1710 - 1770 2110 - 2170 1427.9 - 1447.9 1475.9 - 1495.9 698-716 728-746 777-787 746-756 788 - 798 758 - 768 704-716 734-746 815-830 860-875 830-845 875-890 832-862 791-821 1447.9 - 1462.9 1495.9 - 1510.9 1900 - 1920 1900 - 1920 2010 - 2025 2010 - 2025 1850 - 1910 1850 - 1910 1930 - 1990 1930 - 1990 1910 - 1930 1910 - 1930 2570 - 2620 2570 - 1620 1880 - 1920 1880 - 1920 2300 - 2400 2300 - 2400

In particular, the passbands may comprise conventional mobile radio frequencies.

The front-end circuit includes another band-pass filter having an input terminal and an output terminal. The input terminal of the further bandpass filter is connected to the high-pass connection of the diplexer. The other bandpass filter works with surface acoustic waves, with guided bulk acoustic waves, or with bulk acoustic waves. The further bandpass filter leaves satellite reception signals, z. B. satellite navigation signals such as GPS, Galileo or GLONASS happen.

Thus, a front-end circuit is given, which in addition to mobile radio communication in two different frequency ranges is also capable of simultaneous reception of satellite reception signals.

In an embodiment, the front-end circuit further comprises a multilayer carrier substrate, the substrate comprising electrically insulating layers and a metallization layer disposed therebetween. In the metallization layer is a passive circuit component, for. As a capacitive element, an inductive element or a resistive element or a part of a signal line, structured. The first module and the second module are connected to the substrate. The first module or the second module is connected to the passive circuit component of the multilayer carrier substrate.

In particular, the multilayer carrier substrate can serve to arrange the signal path between the first module with diplexer or with the second duplexer and the second module for optimum signal transmission thereon or therein.

In an embodiment, the first module, the second module, or the multilayer substrate is free of active circuit components. In particular, it is possible to design both the first module and the second module and the multilayer substrate free of active circuit components. Through the integration of passive circuit components in the modules or in the multi-layer substrate can be dispensed with active circuit components, without sacrificing the quality of the signal transmission. In a simple way, thus a well adapted front-end circuit without energy dissipation is obtained by active circuit components.

• 1 ein Schaltbild mit einem Diplexer und einem ersten Duplexer in einem ersten Modul und einem zweiten Duplexer in einem zweiten Modul,
• 2 ein Schaltbild, wobei jeweils ein Filter der Duplexer einen mit Gegentaktsignalen arbeitenden Anschluss umfasst,
• 3 eine Ausgestaltung mit einem weiteren Bandpassfilter,
• 4 eine Querschnittsansicht mit einem ersten Modul, welches auf einem mehrlagigen Trägersubstrat angeordnet ist.

In the following, the front-end circuit is explained in more detail by means of examples and associated schematic figures. Show it:

• 1 a circuit diagram with a diplexer and a first duplexer in a first module and a second duplexer in a second module,
• 2 a circuit diagram, wherein in each case one filter of the duplexer comprises a connection operating with push-pull signals,
• 3 an embodiment with a further bandpass filter,
• 4 a cross-sectional view with a first module, which is arranged on a multilayer carrier substrate.

1 shows a front-end circuit FES with a first module M1 and a second module M2 , The first module M1 includes a diplexer DI , a first duplexer DU1 , an antenna connection AAM1 and a first signal path SP1 , The second module M2 includes a second duplexer DU2 , The diplexer DI is with the antenna connector AAM1 connected. The first signal path SP1 connects the diplexer to the first duplexer DU1 , A second signal path SP2 connects the diplexer DI of the first module M1 with the second duplexer DU2 of the second module M2 ,

The duplexers can be designed as earth-unbalanced or earth-balanced. They can also be designed earth-unbalanced and earth-symmetrical and corresponding connections have differently symmetrically guided connections.

The signal path SP1 which is preferably within the first module M1 is at an optimum signal transmission between the diplexer DI and the first duplexer DU1 customized. In general, it would then no longer be easily possible to use the second duplexer DU2 in the first module M1 to arrange and also an optimal signal transmission between the diplexer DI and the second duplexer DU2 over the signal path SP2 to obtain.

Therefore, according to the invention, the second duplexer DU2 separated from the first module M1 in the second module M2 arranged. The signal routing over the second signal path SP2 is subject to fewer restrictions, thereby providing an overall improved signal routing between the diplexer on the one hand and both duplexers DU1 . DU2 on the other hand.

2 shows a front-end circuit FES in which the diplexer DI a high pass filter HPF and a low-pass filter LPF includes. The diplexer DI includes an antenna connector AADI , a high pass filter port HPFA and a low pass filter port LpfA , The antenna connection of the diplexer AADI is connected to the antenna connector of the front-end circuit. The first duplexer DU1 includes a transmit-receive port SEAD1 , a transmission connection SAD1 and a reception terminal EAD1 , The second duplexer DU2 includes a transmit-receive port SEAD2 , a transmission connection SAD2 and a reception terminal EAD2 , The high-pass filter connection HPFA the high pass filter HPF is with the transmit-receive port SEAD1 of the first duplexer DU1 connected. The low-pass filter connection LpfA the low-pass filter LPF is with the transmit-receive port SEAD2 of the second duplexer DU2 connected. The one with a bandpass filter of the first duplexer DU1 switched transmission connection SAD1 is designed as an unbalanced, ie earth-unbalanced, guided connection. The one with a second bandpass filter of the first duplexer DU1 Interconnected input connection EAD1 is designed for push-pull signals, ie balanced, ie earth-symmetrical.

The second duplexer DU2 includes two bandpass filters. A bandpass filter is provided with a balanced input port EAD2 executed. The other bandpass filter is with the transmit port SAD2 switched and unbalanced executed.

The examples shown in the figures should not be construed as limitations. In particular, all duplexers, diplexers or filters may be earth-symmetrical or earth-unbalanced or earth-symmetrical and earth-unbalanced.

3 illustrates a front-end circuit with another bandpass filter WBPF , The other bandpass filter WBPF is via an input connection EAWBPF with the high-pass filter of the diplexer DI connected. The other bandpass filter WBPF allows satellite receive signals to pass through at the output port AAWBPF the further bandpass filter WBPF can be tapped. The satellite receive signals can be extracted from the first signal path in this manner.

The first duplexer DU1 includes a first bandpass filter BPF 1 , which has a balanced-guided signal terminal, and a second band-pass filter BPF2 , which has an unbalanced led signal terminal. The second duplexer DU2 includes a third bandpass filter BPF3 which has a balanced-guided signal terminal, and a fourth band-pass filter BPF4 , which has an unbalanced led signal terminal.

In general, all signal paths and filters are earth-unbalanced or earth-symmetric. In particular, for the Tx and Rx ports of a duplexer, all four combinations of earth-unbalanced and earth-symmetric are possible.

4 shows the cross section through a carrier substrate TS , which is multi-layered. On the carrier substrate TS are the first module M1 and the second module M2 arranged. The first module M1 and the second module M2 are about bump connections BU with the carrier substrate TS connected and interconnected. The bump connections BU interconnect electrical contacts EK on the bottom of the modules M1 . M2 with electrical contacts EK on the top of the carrier substrate TS , The carrier substrate TS includes three electrically insulating layers, between which two metallization layers MS are arranged. In the metallization layers MS are capacitive elements KE and inductive elements IE arranged. Through holes DK through the layers of the carrier substrate TS allow an interconnection of the modules M1 . M2 with the passive circuit components integrated in the carrier substrate and with electrical contacts arranged on the underside of the carrier substrate EK ,

In an embodiment, the front-end circuit comprises one or more further duplexers. Another duplexer is connected to the diplexer or to one of the duplexers.

In one embodiment, the front-end circuit comprises a triplexer. The triplexer is connected to one of the duplexers. The triplexer may comprise the diplexer. If the diplexer z. B. connected via one of its outputs with another diplexer, the interconnection of the diplexer with the other diplexer results in a triplexer. Thus, accordingly, crossovers with four or five or more outputs are possible.

A front-end circuit is not limited to one of the described embodiments. Variations, which z. B. other modules, filter circuits, passive circuit elements, signal lines or any combinations thereof include, represent embodiments of the invention as well. Other than the above or shown combinations of balanced and unbalanced guided signal paths represent embodiments of the invention as well.

LIST OF REFERENCE NUMBERS

AADI:

Antenna connection of the diplexer

AAM1:

Antenna connection of the first module

AAWBPF:

Output terminal of the other bandpass filter

BPF1, BPF2, BPF3, BPF4:

first, second, third, fourth bandpass filters

BU:

Bump connection

DI:

diplexer

DU1, DU2:

first duplexer, second duplexer

EAD1:

Receive port of the first duplexer

EAD2:

Reception port of the second duplexer

EAWBPF:

Input connection of the other bandpass filter

EK:

electric contact

FES:

Front-end circuit

HPF:

High Pass Filter

HPFA:

High-pass filter connection of the diplexer

IE:

inductive element, capacitive element

KE:

capacitive element

LPF:

Low Pass Filter

LpfA:

Lowpass filter connection

M1, M2:

first module, second module

MS:

metallization

SAD1:

Transmission connection of the first duplexer

SAD2:

Transmission port of the second duplexer

SEAD1:

Transmit-receive port of the first diplexer

SEAD2:

Transmission port of the second duplexer

SK:

circuit component

SP1, SP2:

first signal path, second signal path

TS:

carrier substrate

WBPF:

another bandpass filter

Claims (13)

Front-end circuit (FES), comprising a first module (M1) having an antenna terminal (AAM1), a diplexer (DI) and a first duplexer (DU1), a second module (M2) with a second duplexer (DU2), - A first signal path (SP1) and a second signal path (SP2), wherein the diplexer (DI) has an antenna connection, a low-pass filter with a low-pass connection and a high-pass filter with a high-pass connection, the first duplexer (DU1) has a transceiver connection, a transmission connection and a reception connection, the second duplexer (DU2) has a transceiver connection, a transmission connection and a reception connection, the transmission reception connection of the first duplexer (DU1) via the first signal path (SP1) to the high-pass connection of the diplexer (DI) and the transmission-reception connection of the second duplexer (DU2) via the second signal path (SP2) to the lowpass Connection of the diplexer (DI) is connected, further comprising - Another bandpass filter having an input terminal and an output terminal, wherein the input terminal of the further bandpass filter is connected to the high-pass connection, the further band-pass filter works with surface acoustic waves, with guided bulk acoustic waves or with bulk acoustic waves, and - The other bandpass filter lets satellite receive signals pass. Front-end circuit (FES) according to the preceding claim, wherein the first duplexer (DU1) or the second duplexer (DU2) is designed for processing push-pull signals or for conversion between common-mode signals and push-pull signals. A front-end circuit (FES) according to any one of the preceding claims, wherein the first duplexer (DU1) or the second duplexer (DU2) comprises a surface acoustic wave filter. A front-end circuit (FES) according to any one of the preceding claims, wherein the first duplexer (DU1) or the second duplexer (DU2) comprises a bulk acoustic wave or guided bulk acoustic wave filter. Front-end circuit (FES) according to one of the preceding claims, wherein one of the duplexers (DU1, DU2) selected from first duplexer (DU1) and second duplexer (DU2), works with surface acoustic waves or guided bulk acoustic waves and the other duplexer works with guided bulk acoustic waves or bulk acoustic waves. A front-end circuit (FES) as claimed in any one of the preceding claims, wherein one of the duplexers (DU1, DU2) selected from the first duplexer (DU1) and the second duplexer (DU2) comprises a Balun functionality CRF filter. Front-end circuit (FES) according to one of the preceding claims, wherein - the first duplexer (DU1) bandpass filter with passband in the 2GHz frequency range and - The second duplexer (DU2) bandpass filter with passband in the 1 GHz frequency range comprises. The front-end circuit (FES) according to one of the preceding claims, wherein the first duplexer (DU1) comprises a first bandpass filter having a first passband and a second bandpass filter having a second passband. The front-end circuit (FES) of one of the preceding claims, wherein the second duplexer (DU2) comprises a third bandpass filter having a third passband and a fourth bandpass filter having a fourth passband. Front-end circuit (FES) according to one of the preceding claims, further comprising a multilayer carrier substrate (TS), wherein the substrate comprises electrically insulating layers and at least one metallization layer (MS) arranged therebetween, in which at least one metallization layer (MS) is structured as a passive circuit component, - The first module (M1) and the second module (M2) are connected to the substrate and the first module (M1) or the second module (M2) is connected to the passive circuit component. A front-end circuit (FES) according to the preceding claim, wherein the first module (M1), the second module (M2) or the multilayer substrate are free of active circuit components. Front-end circuit (FES) according to the preceding claim, further comprising a further duplexer, which is connected to the diplexer (DI) or to one of the duplexer (DU1, DU2). A front-end circuit according to the preceding claim, further comprising a triplexer connected to one of the duplexers (DU1, DU2) and comprising the diplexer (DI).

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