CN102437848B

CN102437848B - Multiband coupling architecture

Info

Publication number: CN102437848B
Application number: CN201110288532.6A
Authority: CN
Inventors: C·拉波特; H·埃泽迪纳
Original assignee: STMicroelectronics Tours SAS
Current assignee: STMicroelectronics Tours SAS
Priority date: 2010-09-17
Filing date: 2011-09-19
Publication date: 2016-12-14
Anticipated expiration: 2031-09-19

Abstract

Some embodiments of the present invention relate to multiband coupling architecture.A kind of Multiband coupling circuit, comprising: number is equal to multiple paths of number of frequency bands, each path has the first terminal and the second terminal；3rd terminal and the 4th terminal；Number is equal to multiple distributed coupler of the number in path, all bonders are the most identical and formulate size according to high frequency band, and each bonder is included in the first conducting wire between the first terminal in path and the first port of the second terminal and the second port being connected to be correlated with, and second conducting wire of first be coupled between the 3rd port and the 4th port；First set of the attenuator between the 3rd port and the 3rd terminal of this circuit of bonder；And the filter array between the 4th port and the 4th terminal of this circuit of bonder.

Description

Multiband coupling architecture

Technical field

The present invention relates to electronic equipment, and relate more specifically to wireless transceiver system.The present invention relates more specifically to multiband bonder.

Background technology

Bonder is commonly used to recover a part for power on so-called main transmission line road or present on prevailing transmission circuit for being positioned at neighbouring, another so-called coupling circuit or branch line.Formed (then be referred to as lamped element bonder) according to bonder by discrete passive components or formed (then referred to as distributed coupler) by conducting wire close to each other, that will couple and bonder is divided into two classifications.The present invention relates to the other bonder of second species.The port of main line is typically specified as IN (input) and OUT (output).Those ports in coupling circuit are typically specified as CPLD (coupling) and ISO (isolation).

In numerous applications, a part for the power launched on the line such as need to be used for control the amplifier in emission system power, control according to the loss being associated with the reflection of antenna emission amplifier the linearity, dynamically with antenna match etc..

The major parameter of bonder is:

Insertion loss, it represents the loss (then utilizing two other ports CPLD and ISO being loaded with 50 Ω impedances of bonder to define insertion loss) between the port IN and port OUT of main line；

Coupling, it is corresponding to the loss (this coupling utilizes two other ports OUT and ISO being loaded with 50 Ω impedances to define then) between port IN and port CPLD；

Isolation (isolation), it is corresponding to the loss (this isolation utilizes two other ports OUT and CPLD being loaded with 50 Ω impedances to define) between port IN and port ISO；

Directivity (directivity), it is corresponding to relative to port IN, and the loss between port ISO and port CPLD is poor；And

Coupling, it represents the reflection loss on four ports.

Preferably bonder has unlimited directivity, i.e. when signal flow to the output port of this main line from input port, the port of the branch line before being positioned at the output port of main line of bonder does not exist power.In practice, when the directivity of bonder be enough to allow on the path of the branch line of bonder the power recovered to make a distinction with the flow of power direction in main line (typically larger than 20dBm), this bonder is known as orientation.When two ports of the branch line of bonder are used for having power information simultaneously, bonder is referred to as two-way.

Radio transceiver equipment is increasingly able to operate in some frequency bands.The most in the mobile phone, wherein mobile phone evolves to three frequency bands from double frequency-band to this situation, and evolves to now four frequency bands.

Then transceiver chain includes can launching and the as many path of frequency band of process in reception pattern with this equipment simultaneously.Each path is associated with the bonder formulating size according to pending frequency band.Specifically, the length of main line and branch line depends on this frequency band.Manufacture is made to complicate this demand formulating various sizes of bonder.Additionally, due to the bonder of different length, directivity changes along with bonder difference, and this is less desirable.

In bonder, if the two of the branch line of bonder ports mate completely with the output port of the main line of bonder, then parasitic reflection will not occur.Unfortunately, cannot obtain in practice and such mate completely.Specifically, to it, by coupling, the port of sampling section power mates the most ideally.As a result, parasitic reflection generation error in the data recovered.

The mismatch of the port from its sample information of the branch line of bonder is likely to be of different causes.Generally, bonder is disposed in the dielectric base (such as, the substrate of printed circuit type) treating to be associated with other circuit.There is no guarantee that the coupling completely (usually 50 Ω) of measurement port (CPLD).If additionally, bonder has different size, then this coupling will bear risk that is different along with bonder and that change.

Additionally, in multiband bonder, be connected to the antenna at the output of main line and introduce additional coupling.This coupling the biggest (isolation between two antennas is the poorest), then measurement result changes the most.This bonder is then for the frequency selectivity deficiency in a path for another.

Summary of the invention

One embodiment overcomes all or part of shortcoming of the multiband radio transceiver configuration using a bonder for each path.

Another embodiment reduces the volume of multiband coupled structure.

Another embodiment improves selectivity in terms of the frequency for different paths.

Another embodiment changes less sensitive or the most insensitive by the coupling making the measurement circuit to being connected to measurement port and improves the reliability of measurement.

Therefore, a kind of embodiment provides and includes following Multiband coupling circuit:

Number is equal to multiple paths of number of frequency bands, and each path has the first terminal and the second terminal；

3rd terminal and the 4th terminal；

Number is equal to multiple distributed coupler of the number in path, all bonders are the most identical and formulate size according to the highest frequency band, and each bonder is included in the first conducting wire between the first terminal in path and the first port of the second terminal and the second port being connected to be correlated with, and second conducting wire of first be coupled between the 3rd port and the 4th port；

First set of the attenuator between the 3rd port and the 3rd terminal of this circuit of bonder；And

Filter array between the 4th port and the 4th terminal of this circuit of bonder.

According to an embodiment, this circuit farther includes the second set of the attenuator being associated with filter array.

According to an embodiment, this array includes, for the wave filter connected with attenuator in each path, being sized to of this wave filter makes the frequency band in the path being correlated with pass through.

According to an embodiment, this array includes:

For each path in addition to last path, that connect with attenuator, for current path and the low pass filter of the frequency in the path of relatively low sequence, the 4th terminal of this circuit it is connected to for this series combination of first path；And

For each path in addition to first path, be connected to the path of relatively low sequence low pass filter, for current path and the high pass filter of the frequency in the path of higher ranked.

Size is formulated according to following relation according to an embodiment, wave filter and attenuator:

Isolation I in frequency band i_iThe isolation IB of the bonder equal to path i_iPlus the decay Att provided by the attenuator of path i_i；

Directivity in frequency band i is corresponding to the coupling factor CB of the bonder of path i_iDeduct the isolation I in frequency band i calculated as above_i, and directionality is more than or equal to for desired minimum directivity DIR in all paths.

According to an embodiment, wave filter and attenuator are further by considering that following facts determines size: be coupled to the coupling in the frequency band of another path j of the antenna of the second port of the bonder of path i corresponding to the coupling X between the antenna of the second port of the bonder that is connected to path i and path j_ij, the bonder coupling factor C in frequency band i of path j_jB_i, the decay AF that introduced in frequency band i by the wave filter of path j_jB_i, and by path j attenuator introduce decay Att_jSummation, and be coupled to the coupling in the frequency band of another path j of the antenna of the second port of the bonder of path i less than or equal to the isolation I in frequency band i_i。

According to an embodiment, wave filter and attenuator are further by considering that following facts formulates size: be coupled to antenna the coupling less than or equal to the isolation I in frequency band i in the frequency band of another path j of the second port of the bonder of path i_i, and it corresponds to:

For there is any path j of the sequence less than sequence i, the coupling X between the antenna of the second port being connected to the bonder of path i and path j_ij, the bonder coupling factor C in frequency band i of path j_jB_i, the decay LF that introduced in frequency band i by the low pass filter of path j_jB_i, and by path j attenuator introduce decay Att_jSummation；And

For there is any path j of the sequence more than sequence i, the coupling X between the antenna of the second port being connected to the bonder of path i and path j_ij, the bonder coupling factor C in frequency band i of path j_jB_i, the decay LF that introduced in frequency band i by the high pass filter (49j) of path j-1 to path i_jB_iSummation and by path j attenuator introduce decay Att_jSummation.

According to an embodiment, this farther includes level and is associated in the set of the resistive splitter between wave filter and the 4th terminal.

According to an embodiment, the terminal of the splitter being associated with last path passes through resistance element ground connection, and the value that this resistance element has is three times of the corresponding resistor element of splitter.

Size is formulated based on following relation according to an embodiment, wave filter and splitter:

Isolation I in frequency band i_iThe isolation IB of the bonder equal to path i_iSummation plus the decay provided by the splitter between first path and path i；

Directivity in frequency band i is corresponding to the coupling factor CB of the bonder of path i_iDeduct the isolation I in frequency band i calculated as above_i, and directionality is more than or equal to for desired minimum directivity DIR in all paths；And

It is connected to the antenna of the second port of the bonder of the path i coupling in the frequency band of another path j corresponding to the coupling X between the antenna of the second port being connected to the bonder of path i and path j_ij, the bonder coupling factor C in frequency band i of path j_jB_i, the decay AF that introduced in frequency band i by the wave filter of path j_jB_i, and the summation of decay summation that provided by the splitter between first path and path j, and be connected to the coupling in the frequency band of another path j of the antenna of the second port of the bonder of path i and be less than or equal to the isolation I in frequency band i_i。

Above and other objects, features and advantages will be discussed in detail in the non restrictive description of the following specific embodiment being combined with accompanying drawing.

Accompanying drawing explanation

Fig. 1 is that the simplification of the block form of common type of wireless radio transmission chain represents；

Fig. 2 is the block diagram that multiband radio launches an embodiment of chain；

Fig. 3 illustrates the first Multiband coupling circuit solution；

Fig. 4 schematically shows an embodiment of Multiband coupling circuit with block form；

Fig. 5 shows an embodiment of the bonder of the circuit of Fig. 4；

Fig. 5 A shows a deformation of the attenuator of the circuit of Fig. 5；

Fig. 6 gives the details of an embodiment of the coupling circuit of Fig. 4；

Fig. 7 gives the details of another embodiment of the coupling circuit of Fig. 4；

Fig. 8 shows an embodiment of the resistive splitter of the circuit of Fig. 7；

Fig. 9 gives the details of another embodiment of the coupling circuit of Fig. 4；And

Figure 10 A, Figure 10 B, Figure 10 C and Figure 10 D show the embodiment of wave filter.

Detailed description of the invention

In different drawings, identical element is designated identical reference.For clarity sake, illustrate only those elements useful to understanding the present invention, and these elements will be described.Specifically, the upstream circuitry to multiband coupled structure and the details of circuit downstream are not given.The present invention is compatible with these circuit commons.

Fig. 1 is the block diagram of the Usual examples of the chain can launched in some frequency bands.Such circuit is such as equipped with the communication equipment of mobile-telephone-type.

Electric transmission circuit 10 (SEND) can generate armed signal Tx according to the frequency band used_i(wherein i is between 1 and n).These signals are sent to power amplifier 11_i(PA) on, these power amplifiers 11_i(PA) them are made to export across the various process illustrated with dotted line and match circuit 12 accordingly_i.These circuit 12_i(among other things and without limitation) includes for launching antenna 13_iImpedance matching equipment.In order to regulation amplifier 11_iOr the power of any other element (adjustable impedance matching network etc.), such as at circuit 12_iOutput and the antenna of correspondence between insert bonder 2_i.Path splitter (not shown) can be inserted between bonder and antenna.Such splitter is used for separating transmitting with receiving, and receives and is processed by unshowned radio reception circuit.

Each bonder 2_iIncluding being inserted in amplifier 11_iWith antenna 13_iBetween (or at circuit 12_iOutput and antenna 13_iBetween) main line.So-called input port or path IN are positioned at amplifier 11_iSide, and so-called output port or path OUT (sometimes referred to as DIR) are positioned at antenna 13_iSide.A part for the power of main line is sampled by coupling circuit or the branch line of bonder.The port of bonder CPLD (corresponding to the end in port IN side of branch line) provides and measures relevant information.This information (among other things) depends on the loss caused due to the reflection of antenna.As bidirectional coupler, the end ISO in port OUT side of branch line does not use.This end ISO is loaded with the reference impedance (usually 50 Ω) of circuit.In the example of fig. 1, the measurement of the reflection loss that instruction is generated by antenna is for by means of circuit 14_iAnd circuit 15 (DETECT)_i(CTRL) matching amplifier gain is carried out, this circuit 14_i(DETECT) for detecting the port at corresponding bonder Level on CPLD, this circuit 15_i(CTRL) receive the information by detectors measure and control corresponding amplifier 11_iGain.

If this antenna has this function, then the measurement of the reflection loss of antenna can also support the Dynamic Matching of antenna.

As it has been described above, the increase of control circuit and testing circuit negatively have impact on minimizing of wireless radio transmission circuit.Additionally, in most applications and the most in the mobile phone, use single circuit in preset time, it is therefore desirable at least can Compliance control circuit and testing circuit.

Fig. 2 is the block diagram that will compare with Fig. 1, which illustrates the chain with Multiband coupling circuit.

As previously, the circuit 10 with n path can generate signal Tx on different frequency bands_i(wherein i is between 1 and n), this signal will be sent to adjustable gain emission amplifier 11_i.Amplifier 11_iCorresponding output be sent to n of Multiband coupling circuit 3 and input IN_iOn.This circuit includes the antenna 13 being intended to be connected to be assigned to different frequency bands_iEqual number of output OUT_i.Circuit 3 only includes an a port CPLD and port ISO.Port CPLD is connected to detector 14, and the output of detector 14 is connected to control circuit 15.The output of control circuit 15 is connected to amplifier 11_iCorresponding gain control input.Can be at control circuit 15 and amplifier 11_iGain control input between insert signal switching circuit.

In the figure 2 example, symbolically having illustrated splitter 16 (SPLIT) with dotted line, these splitters 16 (SPLIT) are at antenna 13_iLevel is by transmitting stream and receives stream separately, and by signal Rx_iIt is supplied to receive circuit (not shown).

In order to simplify description, the different parts of path, frequency band and coupling circuit are identified by their sequence i (between 1 and n).

Fig. 3 shows the usual example of the Multiband coupling circuit 3 ' that can use in the chain of Fig. 2.Circuit 3 ' includes n bonder 2_i, bonder 2_iThe corresponding input of main line and output limit the different terminal IN of circuit 3 '_iWith terminal OUT_i.Different bonders 2_iTerminal CPLD_iWith terminal ISO_iThe terminal CPLD and terminal ISO of circuit 3 ' it is connected to via impedance matching network.Generally, each terminal CPLD_iIt is connected to terminal CPLD by the series combination of two resistor R1, is shared by all connections for one in these resistors.Identical structure has been reproduced in terminal ISO side.All resistor R1 have identical value.This value calculates according to each bonder desired impedance R (usually 50 ohm), and corresponding to R1=R (n+1)/(n-1).Utilize such value, it is thus achieved that depend on the decay between two ports of number of frequency bands.

Fig. 4 shows an embodiment of Multiband coupling circuit with block form.

As the circuit of Fig. 3, distributed coupler 31_iIt is assigned to each frequency band or path.Bonder 31_iSuch as there is isometric same line (same shape, material etc.).Due to line length identical the fact, so all bonders have an identical intrinsic directivity, and therefore coupling circuit has the directivity independent of frequency band.It is however also possible to provide formulate the size of each bonder individually according to relevant path.

Each port ISO_iThe terminal ISO of circuit 3 it is connected to by the array 4 of wave filter (FILT) and attenuator (ATT) or wave filter and splitter.In terminal CPLD side, each port CPLD_iThe terminal CPLD of circuit 3 it is connected to by the array 5 of attenuator (ATT).

The function of array 4 is to filter at its out-of-band signal for each path, and i.e. those can be received by antenna but the signal not used.

Some embodiments of filter array will be described about Fig. 6, Fig. 7 and Figure 10.

Simplifying embodiment according to one, all bonders are all same as the bonder 2 of Fig. 3₁。

Preferably, bonder 31_iThere is the structure improved in terms of directivity, to avoid the generation of given fault, such as, if reflection loss is corresponding to more than the decay of directivity (signal of reflection is more than what directional factors decayed), be likely occurred detection mistake.

Fig. 5 shows the type for the circuit used in the diagram, has the bonder 31 of the directivity of improvement_iAn embodiment.Distributed coupler 31_iIncluding main line 321, it is intended to by its two corresponding input port IN_iWith output port OUT_iIt is inserted on transmission line.Branch line (being formed by two parts 322 and 323 parallel to circuit 321) defines the port CPLD being intended to transmit the information proportional with the power of transmitting on circuit 321_iWith port ISO_i.Part 322 and part 323 are preferably symmetrical, are equal length.They corresponding ends are connected to port CPLD_iWith port ISO_i.Their corresponding inner end is connected to attenuator 324 and attenuator 325, thus forms impedance Z between these inner end and ground.

Attenuator 324 and attenuator 325 are preferably selected as providing the decay at least equal to coupler directivity half.There is the bonder of-30dB directivity as example, it means that attenuator 324 and attenuator 325 are each at least 15dB.The coupler structure that figure 5 illustrates allows to eliminate at port CPLD_iWith port ISO_iPresent on load impact.

In practice, bonder 31_iFormed with the form of strip conductor that supported by dielectric base.As a rule, circuit is straight line, and selects their length according to operation frequency and the desired coupling level of bonder.All bonders as described with respect to FIG 5 are corresponding to the bidirectional coupler described in french patent application No.2923950 (B8533-07-TO-295/296) or U.S. Patent application No.2009/0128255, and above patent application is all incorporated by reference in this.

Fig. 5 A shows an embodiment of attenuator 324 or attenuator 325.

This attenuator is formed by the resistor R32 between the inner end and ground of relevant part is in parallel with capacitor C.Such as, resistance R32 is 50 ohm, and electric capacity C is at picofarad range.

Fig. 6 is the block diagram of an embodiment of the coupling circuit of Fig. 4.

Assuming that attenuator array 5 includes an attenuator 52 on each path.Such as, for each path (at each terminal CPLD_iAnd between terminal CPLD) for, use by three resistance element R with identical value₅π type pad (pi-pad) formed.First resistor is by terminal CPLD_iIt is connected to terminal CPLD.Other two resistors are respectively by terminal CPLD_iWith CPLD ground connection.

In terminal ISO side, array 4 includes wave filter 42 for each path i_iWith attenuator 44_i.The π type pad that attenuator is e.g. similar with the π type pad formed in terminal CPLD side.

The wave filter 42 in each path_iBe sized to only conduct the frequency band in relevant path.

In order to simplify description, it is assumed that the order that n the path of Fig. 6 increases with frequency is arranged.Thus the first wave filter 42₁It is that there is the low pass filter (LPF) that cut-off frequency is selected to only allow the passband of first path pass through.Wave filter 42₂To wave filter 42_n-1In each be its band filter (BPF) being sized to only allow frequency band pass through.Wave filter 42_nIt it is the high pass filter (HPF) only allowing last frequency band pass through according to it is sized such that.Of course, it is possible to use the band filter allowing the frequency of relevant frequency band pass through to substitute low pass filter 42₁With high pass filter 42_n。

Such structure makes the parasitic signal coming from the coupling between antenna in terminal ISO side by filter cutoff.

The wave filter of array 4 and the dimensioned of attenuator depend on bonder 31_iInherent character and antenna parasitic couplings each other.

Based on inherent character, the following is known (measurable):

X_ij, antenna 31_iWith antenna 31_jBetween coupling；

CB_i, the circuit total coefficient of coup in frequency band i is (at terminal IN_iAnd difference between signal present on terminal CPLD)；

C_iB_j, bonder 31_iThe coupling in frequency band j (at terminal IN_iWith terminal CPLD_iPresent on difference between signal)；

IB_i, bonder 31_iThe isolation in frequency band i (at terminal IN_iWith terminal ISO_iPresent on difference between signal)；And

DIR, the desired minimum directivity of all frequency bands.

Notice, wave filter 42_iWith attenuator 44_iCharacteristic as follows:

Att_i, by attenuator 44_iThe decay provided；And

AF_iB_j, by wave filter 42_iThe decay provided in frequency band j,

The following isolation, directivity and the coupled relation that are obtained by circuit 3 can be expressed as follows:

Circuit I_iTotal isolation in frequency band i is (at terminal IN_iAnd difference between signal present on ISO) corresponding to the isolation of bonder of path i plus by attenuator 44_iDecay (the I provided_i=IB_i+Att_i)；

The coupling factor of the bonder that the directivity in frequency band i corresponds to path i deducts the isolation directionality in frequency band i calculated as above and have to be larger than or equal to for the desired minimum directivity DIR (CB in all paths_i-I_i≥DIR)；And

The coupling in the frequency band of each other paths j of the antenna of path i is corresponding to antenna 13_iWith antenna 13_jBetween coupling X_ij, bonder 31_jCoupling factor C in frequency band i_jB_i, by the wave filter 42 of path j_jThe decay AF introduced in frequency band i_jB_iAnd by attenuator 44_jThe decay Att introduced_jSummation.This summation (X_ij+C_jB_i+AF_jB_i+Att_j) be necessarily less than or equal to the isolation I in frequency band i_i。

The equation system obtained for different frequency bands allows the value that determines being given to wave filter and attenuator.

In network 5 side, decay is selected to the expectation coupling level guaranteeing in each frequency band and the desired impedance matching guaranteeing between different frequency bands.

Fig. 7 shows the figure of another embodiment of coupling circuit.

It is with the difference of the embodiment of Fig. 6, attenuator 44 splitter 46_i(SPL-splitter) replaces.Splitter 46 for example, resistive splitter, each includes three resistors of T-type structure.The array of wave filter 42 is unmodified.

Fig. 8 shows splitter 46_iAn embodiment.

At each wave filter 42_i, terminal (at random be referred to as lead-out terminal) in terminal ISO side be connected to the splitter 46 in the path being correlated with_iThe first resistor R2₁End.Splitter 46 except last path_nOutside, the first resistor R2₁The second resistor R2 with same splitter₂Series connection, this second resistor R2₂May be coupled to the splitter 46 in next path_i+1The 3rd resistor R2₃.Splitter 46 except first path₁In addition, splitter 46_iThe first resistor R2₁With the second resistor R2₂Abutment therefore by the 3rd resistor R2 of this splitter₃It is connected to the splitter 46 in previous path_i-1The second resistor R2₂。

The splitter 46 of first path₁The 3rd resistor R2₃It is connected to the terminal ISO of circuit 3.The splitter 46 in last path_nThe second resistor by resistor R3 ground connection (Fig. 7).

The value of resistance R3 corresponds to three times of the value of resistance R2.The resistive splitter 46 so formed_iCascade between different paths.

Functionally, each bonder 31_iAt its port ISO_iOn see value for the resistor of R3, and the terminal ISO of circuit 3 also sees the resistor that value is R3.

The dimensioned of the coupling circuit illustrated the most in the figure 7 is carried out the most as follows.

Use the representation limited about Fig. 6, and by by the splitter 46 being ordered as i_iThe pad markings provided is Spl_i, it is thus achieved that following relation:

I_i=IB_i+Spl₁+...+Spl_i；

CB_i-I_i≥DIR；And

Any j for different from i:

X_ij+C_jB_i+AF_jB_i+Spl₁+...+Spl_j≤I_i。

Fig. 9 shows the another embodiment of coupling circuit.

Embodiment such as Fig. 6 is compared, and attenuator is arranged in terminal ISO_iSide, rather than terminal ISO side.Additionally, wave filter is in different path-level cascades.(in addition to the n of last path) includes and its attenuator 44 in each path_iThe low pass filter 48 of series connection_i(wherein i is from 0 to n-1), low pass filter 48i is for filtering all frequencies of the frequency band more than current path i.Additionally, each path (in addition to first path) is by high pass filter 49_iIt is connected to the low pass filter 48 of previous path_i-1Output, this high pass filter 49_iFor terminating in all frequencies under the frequency band of current path.Terminal ISO is connected to wave filter 48₁Output and wave filter 49₂Output.

Such embodiment allows to form simpler wave filter, and in practice, band filter generally associates with high pass filter.

Property reason, low pass filter and high pass filter are at least 2 rank by choice, and preferably 3 rank.

Use the representation about Fig. 6 definition, and will be by wave filter 48_iThe pad markings provided in frequency band j is LF_iB_jAnd by wave filter 49_iThe pad markings provided in frequency band j is HF_iB_j, it is thus achieved that following relation:

I_i=IB_i+Att_i；

CB_i-I_i≥DIR；

For any j less than i:

X_ij+C_jB_i+Att_j+LF_jB_i≤I_i；And

For any j more than i:

X_ij+C_jB_i+Att_j+HF_j-1B_i+...+HF_iB_i≤I_i。

Figure 10 A to Figure 10 D shows the low pass filter and the example of high pass filter that can be formed in network 4.

Figure 10 A shows the example of 3 rank low pass filters 48.Three inductance L11, L12 and L13 connect, and the abutment of these series combination is directly grounded by capacitor C11 and capacitor C12 respectively.

Figure 10 B shows the example of 3 rank high pass filters 49.Three capacitors C21, C22 and C23 connect, and the abutment of these series combination is directly grounded by inductance L21 and inductance L22 respectively.

Figure 10 C and Figure 10 D shows other examples of corresponding low pass filter 48 and high pass filter 49.Compared with Figure 10 A and Figure 10 B, inductance L11, L12, L13, L21 and L22 are substituted by resistor R11, R12, R13, R21 and R22 respectively.

Selection between inductive element or resistance element such as depends on available technology and depends particularly on the probability being easily integrated inductive element in the art.Form resistive in an integrated fashion and capacitive equipment is typically easy to.

Having been described with various embodiment, those skilled in the art will find various changes and modifications.Specifically, based on being given above functional instruction and the inherent characters of different bonders used, the size given for the different parts of described coupling circuit is positioned at the limit of power of those skilled in the art.Although additionally, describe the present invention referring in particular to chain, but it is also applied for Multiband coupling circuit of reception chain.

Claims

1. a Multiband coupling circuit, including:

Number is equal to multiple paths of number of frequency bands, and each path has the first terminal and the second end Son；

3rd terminal and the 4th terminal；

Number is equal to multiple distributed coupler of the number in described path, and all bonders are homogeneous Together and formulate size according to high frequency band, and each bonder is included in and is connected to be correlated with Path described the first terminal and the first port of described second terminal and the second port between The first conducting wire, and between the 3rd port and the 4th port, be coupled to described first lead Second conducting wire of electric line；

Between described 3rd port and described 3rd terminal of described circuit of described bonder Attenuator first set；And

Between described 4th port and described 4th terminal of described circuit of described bonder Filter array.

Circuit the most according to claim 1, farther includes and described filter array Second set of the attenuator being associated.

Circuit the most according to claim 2, wherein said array includes, for each For path, the wave filter connected with attenuator, it is sized to allow described relevant road The described frequency band in footpath passes through.

Circuit the most according to claim 2, wherein said array includes:

For each path in addition to last path, that connect with attenuator, For current path and the low pass filter of the frequency in the path of relatively low sequence, for first path This series combination be connected to described 4th terminal of described circuit；And

For each path in addition to described first path, it is connected to relatively low sequence The low pass filter in path, for current path and the high pass of the frequency in the path of higher ranked Wave filter.

Circuit the most according to claim 2, wherein said wave filter and described attenuator According to following relation formulation size:

Isolation I in frequency band i_iThe isolation IB of the bonder equal to path i_iPlus by path i Attenuator provide decay Att_i(I_i=IB_i+Att_i)；

Directivity in frequency band i is corresponding to the coupling factor CB of the bonder of path i_iDeduct Isolation I in frequency band i calculated as above_i, and described directivity more than or equal to for The desired minimum directivity DIR (CB in all paths_i-I_i≥DIR)。

Circuit the most according to claim 5, wherein said array includes, for each For path, the wave filter connected with attenuator, it is sized to allow described relevant road The described frequency band in footpath passes through；And

Wherein said wave filter and described attenuator are further by considering that following facts is formulated Size: be coupled to the antenna of the second port of the bonder of path i at the frequency band of another path j In coupling corresponding to the sky of the second port of the bonder that is connected to described path i and path j Coupling X between line_ij, the bonder coupling factor C in frequency band i of path j_jB_i, by road The decay AF that the wave filter of footpath j introduces in frequency band i_jB_iAnd introduced by the attenuator of path j Decay Att_jSummation (X_ij+C_jB_i+AF_jB_i+Att_j), and it is coupled to the coupling of path i The coupling in the frequency band of another path j of the antenna of the second port of device is less than or equal at frequency With the isolation I in i_i。

Circuit the most according to claim 5, wherein said array includes:

For each path in addition to described first path, it is connected to relatively low sequence The low pass filter in path, for current path and the high pass of the frequency in the path of higher ranked Wave filter；

Wherein said wave filter and described attenuator are further by considering that following facts is formulated Size: be coupled to the antenna of the second port of the bonder of path i at the frequency band of another path j In coupling less than or equal to isolation I in frequency band i_i, and correspond to:

For there is any path j of the sequence less than sequence i, it is connected to described path i And the coupling X between the antenna of the second port of the bonder of path j_ij, the bonder of path j Coupling factor C in frequency band i_jB_i, introduced in frequency band i by the low pass filter of path j Decay LF_jB_i, and by path j attenuator introduce decay Att_jSummation (X_ij+C_jB_i+Att_j+LF_jB_i)；And

For there is any path j of the sequence more than sequence i, it is connected to described path i And the coupling X between the antenna of the second port of the bonder of path j_ij, the bonder of path j Coupling factor C in frequency band i_jB_i, by the high pass filter of path j-1 to path i at frequency band The decay HF introduced in i_jB_iSummation and by path j attenuator introduce Att_jTotal (X_ij+C_jB_i+Att_j+HF_j-1B_i+…+HF_iB_i)。

Circuit the most according to claim 1, farther includes level and is associated in described wave filter And the set of the resistive splitter between described 4th terminal.

Circuit the most according to claim 8, is wherein associated with last path The terminal of described splitter passes through following resistance element ground connection, and the value of described resistance element is Three times of the corresponding resistor element of splitter.

Circuit the most according to claim 8, wherein said wave filter and described splitter Size is formulated based on following relation:

Isolation I in frequency band i_iThe isolation IB of the bonder equal to path i_iPlus by the first via Summation (the I of the decay that the splitter between footpath and path i provides_i=IB_i+Spl₁+…+Spl_i)；

Directivity in frequency band i is corresponding to the coupling factor CB of the bonder of path i_iDeduct Isolation I in frequency band i calculated as above_i, and described directivity more than or equal to for The desired minimum directivity DIR (CB in all paths_i-I_i≥DIR)；And

It is connected to the antenna of the second port of the bonder of path i in the frequency band of another path j Coupling corresponding to: be connected to the sky of the second port of the bonder of described path i and path j Coupling X between line_ij, the bonder coupling factor C in frequency band i of path j_jB_i, by road The decay AF that the wave filter of footpath j provides in frequency band i_jB_i, and by described first path and road The summation of the summation of the decay that the splitter between the j of footpath provides (X_ij+C_jB_i+AF_jB_i+Spl₁+…+Spl_j), and be connected to path i bonder second The coupling in the frequency band of another path j of the antenna of port is less than or equal in frequency band i Isolation I_i。